CQ^ariteU lltnitteraUg Slibtatij 
 
 Strata, S^ctti ^nck 
 
 BOUGHT WJTH THE INCOME OF THE 
 
 SAGE ENDOWMENT FUND 
 
 THE GIFT OF 
 
 HENRY W. SAGE 
 
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Cornell University Library 
 arV19401 
 Manual of the diseases of the eve 
 
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PLATE 
 
 CANAL OF 
 SCHLEHH 
 
 ANTERIOR CHAMBER 
 
 POSTERIOR 
 .-"fcHAHBER 
 
 ; .GRA ERRATA 
 
 LENS 
 
 SUSPENSORY 
 LIGAMENT 
 
 VSIREOUS 
 
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 V 
 
 
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 -RETINA 
 
 ^—CHOROID 
 
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 VITREOUS 
 
 4-CENTRAL ARTERY 
 OF RETINA 
 
 Fig. 1. — Horizontal Section of the Eyeball. Magnified about 3 H X- 
 
MANUAL 
 
 OP THE 
 
 DISEASES OF THE EYE 
 
 FOR STUDENTS 
 AND GENERAL PRACTITIONERS 
 
 BY 
 
 CHARLES H. MAY, M.D. 
 
 Director and Visiting Surgeon, Eye Service, Bellevue Hospital, New York; Attending 
 Ophthalmic Surgeon to the Mt. Sinai Hospital, New York; Consulting Ophthal- 
 mologist to the French Hospital, to the Italian Hospital, New York, 
 and to the Monmouth Memorial Hospital; Formerly Chief of 
 Clinic and Instructor in Ophthalmology, College of 
 Physicians and Surgeons, Medical Department, 
 Columbia University, New York 
 
 flfntb BOitfon, IRcpiscO 
 
 WITH 377 ORIGINAL ILLUSTRATIONS 
 INCLUDING 22 PLATES, WITH 71 COLORED FIGURES 
 
 NEW YORK 
 WILLIAM WOOD AND COMPANY 
 
 1919 
 
 f^ /A 1.) t.l I I I 
 
Copyright, 1917, by 
 WILLIAM WOOD AND COMPANY 
 
 First Edition, August, 1900. 
 
 Second Edition, September, 1901. Reprinted October, 1901, and July, 1902. 
 
 Tliird Edition, August, 1903. Reprinted .January, 1904, and October, 1904. 
 
 Fourth Edition, August, 1905. Reprinted October, 1906. 
 
 Fifth Edition, August, 1907. Reprinted August, 1908. 
 
 Sixth Edition, August, 1909. Reprinted August, 1910. 
 
 Seventh Edition, July, 1911. Reprinted July, 1913. 
 
 Eighth Edition, August, 1914. Reprinted August, 1916, and February, 1917. 
 
 Ninth Edition, August, 1917. Reprinted July, 1919. 
 
 German Translation by Dr. E. Oppenheimer: Hirschwald, Berlin, 1904. 
 
 Second German Edition in Press in 1914. 
 ItaUan Translation by Prof. E. Trombetta; Unione Tipograflco, Turin, 1905. 
 
 Second Italian Edition, January, 1909. 
 
 Third ItaUan Edition, January, 1916. 
 British Edition by Mr. Claud Worth; Ballli6re, Tiudall & Cox, London, 19,15. 
 
 Second British Edition, March, 1908. 
 
 Third British Edition, October, 1911. 
 
 Foxu:th British Edition, January, 1915. Reprinted February, 1917. 
 French Translation by Dr. Bouin; Steinheil, Paris, 1907. 
 
 Seconc} French Edition, May, 1911. 
 
 Third French Edition, January, 1914. 
 Dutch Translation by Dr. G. J. Schoute; Meulenhofl, Amsterdam, 1907. 
 
 Second Dutch Edition, September, 1910. 
 
 Third Dutch Edition, June, 1916. 
 Spanish Translation by Prof. C. E. Flnlay; Salvat & Co., Barcelona, 1907. 
 
 Second Spanish Edition, October, 1909. 
 
 Third Spanish Edition, March, 1912. 
 
 Poiu'th Spanish Edition, July, 1914. 
 Japanese Translation by Dr. T. Hldaka; Nankodo, ToMo, 1909. 
 
 Second Japanese Edition, August, 1914. 
 Chinese Translation by Dr. T. M. Li (in preparation). 
 
 ( PUBLrSHERS PRINTINQ COMPANY. NEW YORK 
 
PREFACE TO THE NINTH EDITION 
 
 The eighth edition of this manual appeared in August, 
 1914, and was reprinted in August, 1916, and again in Feb- 
 ruary, 1917. In presenting the ninth edition, the author 
 desires to express his appreciation of the continued favor 
 with which his work is received. Every page has been care- 
 fully examined; alterations and additions have been in- 
 corporated to improve the text wherever possible. 
 
 The volume has been kept up to date, but has not been 
 increased in size, the original plan of presenting a book for 
 the student and general practitioner having been adhered to. 
 
 CHARLES H. MAY, M.D. 
 
 698 Madison Avenue, New York, 
 August, 1917. 
 
 PREFACE TO THE FIRST EDITION 
 
 In the following pages the author has endeavored to pre- 
 sent a concise, practical, and systematic Manual of the Dis- 
 eases of the Eye, intended for the student and the general 
 practitioner of medicine. The great difficulty in preparing 
 a book of this sort is to say enough but not too much. With 
 this idea in view, the author has made the volume sufficiently 
 comprehensive, up to date, and yet of limited size. 
 
 This restriction in size has been accomplished by omitting 
 excessive detail, extensive discussion, and lengthy accounts 
 of theorioB and rare conditions. The author has endeavored 
 to give the fundamental facts of ophthalmology and to cover 
 all that is essential in this branch of medicine, always keeping 
 in mind that the book has been written for students and 
 general practitioners. Space, therefore, has been allotted as 
 the necessities of such readers require, estimated by an ex- 
 tended experience in teaching. Thus, rare conditions have 
 
iv PREFACE 
 
 merely been mentioned; uncommon affections, of interest 
 chiefly to the specialist, have been dismissed with a few lines; 
 and common diseases, which the general practitioner is most 
 frequently called upon to treat, have been described with 
 comparative fulness. 
 
 The book is not recommended as a substitute for the larger 
 works, but as a means of supplying a foundation to which 
 further knowledge may be added by reference to more ex- 
 tensive and comprehensive text-books. 
 
 The illustrations, excepting a few cuts of instruments, are 
 original, and have been inserted wherever it seemed that they 
 would be of value in elucidating the text. The colored plates 
 present the common external diseases of the eye and those 
 changes in the fundus, the recognition of which is important 
 in connection with general diseases, including affections of the 
 nervous system, as well as for ophthalmic diagnosis; hence the 
 volume also supplies an atlas. 
 
 C. H. M. 
 August, 1900. 
 
CONTENTS 
 
 CHAPTER PAGE 
 
 I. External Examination op the Eye by Means op 
 
 Inspection and Palpation 1 
 
 II. Subjective or Functional Examination op the Eye . . 10 
 III. Objective Examination op the Eye Conducted in 
 THE Dark Room. Oblique Illumination and the 
 
 Ophthalmoscope 20 
 
 rV. AppECTioNS op the Eyelids 38 
 
 V. Diseases op the Lacrymal Apparatus 67 
 
 VI. Diseases op the Orbit 77 
 
 VII. Diseases op the Conjunctiva -92 
 
 VIII. Diseases op the Cornea 133 
 
 IX. Diseases op the Sclera 158 
 
 X. Diseases op the Iris 164 
 
 XI. Diseases op the Ciliary Body 177 
 
 XII. Diseases op the Choroid 182 
 
 XIII. Diseases op the Whole Uveal Tract. Uveitis.... 188 
 
 XIV. Intraocular Tumors 194 
 
 XV. Glaucoma 198 
 
 XVI. Diseases op the Vitreous 220 
 
 XVII. Diseases op the Lens 227 
 
 XVIII. Diseases op the Retina 250 
 
 XIX. Diseases op the Optic Nerve 270 
 
 XX. Amblyopia, Amaurosis, and Disturbances op Vision 
 
 without Apparent Changes 280 
 
 XXI. General Optical Principles 293 
 
 XXIL. Optical Consideration op the Eye 308 
 
 XXIII. Errors op Repraction 326 
 
 XXIV. Anomalies op Accommodation 352 
 
 XXV. Disturbances op Motility op the Eye 357 
 
 XXVI. Ocular Therapeutics. General Rules for Eye 
 
 Operations 393 
 
 XXVII. The Ocular Manifestations op General Diseases . . 413 
 
 V 
 
DISEASES OF THE EYE 
 
 CHAPTER I 
 
 EXTERNAL EXAMINATION OF THE EYE BY 
 MEANS OF INSPECTION AND PALPATION 
 
 Introduction. — Thorough examination of the eye requires 
 the adoption of a certain routine. The history of the patient's 
 complaint will lead the trained observer to concentrate his 
 attention upon the affected part of the eye; but until pro- 
 ficiency is gained through experience it is not safe to depart 
 from a systematic plan of examination. 
 
 The eye, being intimately associated with the rest of the 
 body, must not be regarded as an isolated organ. Hence a 
 knowledge of the condition of the system is often valuable in 
 the diagnosis and successful treatment of ocular disease. The 
 parts immediately surrounding the eye must also receive care- 
 ful attention. 
 
 Systematic examination of the eye may be divided into 
 
 1. Objective. 
 
 2. Subjective or functional. 
 
 The objective examination may be subdivided into 
 
 (a) Examination of the appendages and the anterior por- 
 tions of the eyeball by means of inspection and palpation; 
 this part of the examination is usually conducted in daylight. 
 
 (b) Examination of the cornea and of the interior of the 
 eyeball in the dark room, with artificial light, by means of 
 oblique illumination and the ophthalmoscope. 
 
 Inspection. — Those parts of the eye which admit of ex- 
 amination by daylight are best illuminated by seating the 
 patient so that he faces a window. Taking a general 
 survey of the eyes, we notice certain prominent symptoms, 
 
 1 
 
EXTERNAL EXAMINATION OF THE EYE 
 
 such as swelling, congestion, discharge, lacrymation, 
 photophobia, etc. 
 
 Proceeding from the superficial to the deeper parts, we 
 commence with the lids, noticing their thickness, color, and 
 position; the condition of their margins, whether swollen, 
 crusted, or ulcerated; the power of opening and closing; the 
 size of the palpebral aperture; and the position and perme- 
 ability of the lacrymal puncta. Passing to the region of 
 the tear-sac we see whether this is swollen, and whether 
 
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 Fig. 2. — Eversion of the Lower Lid. 
 
 Fig. 3. — First Step in Eversion of the 
 Upper Lid. 
 
 pressure with the tip of the inde.x finger causes escape of 
 secretion. We examine the condition and direction of the 
 cilia, and notice'whether any are misdirected. 
 
 Next we inspect the inner or conjunctival surface of the 
 lids, observing any change in color, smoothness, thickness, 
 and secretion of this membrane, and looking for foreign 
 bodies. 
 
 Exposure of the Conjunctiva of the Lower Lid is easy: 
 Place the thumb near the margin of the lid, press downward, 
 while the patient looks up (Fig. 2). 
 
 Eversion of the Upper Lid requires a little practice : Grasp 
 the central lashes between the thumb and index finger of the 
 right hand and draw the lid strongly downward and away 
 
EXPOSURE OF THE CONJUNCTIVA 3 
 
 from the globe, directing the patient to look down (Fig. 3) ; 
 place the left thumb (or a probe held horizontally) at the 
 upper margin of the tarsus and press downward, at the same 
 time quickly turning the lid. Having turned the lid, it can 
 be kept everted by shifting the left thumb against the margin, 
 
 Fig. 4. — Keeping the Upper Lid Everted. 
 
 Fig 5. — Expos jre of the Retrotarsal Fold 
 of the Conjunctiva of the Upper Lid. 
 
 tne otner nngers ot the left hand being applied above the 
 patient's forehead (Fig. 4). 
 
 Another method of inverting the upper lid, which re- 
 quires but one hand, is as follows : Place the tip of the index 
 finger just above the margin of the upper lid and the thumb 
 immediately below the border of the lower hd. Tell the 
 patient to look down. Push the upper lid back so as to tilt 
 its edge away from the eyeball. With the thumb slide the 
 lower under the upper lid. The latter is now grasped be- 
 tween the index finger and thumb and is readily inverted 
 by a sort of semirotatory movement. The whole act is 
 continuous, easy, is done quickly and with little discomfort 
 to the patient. 
 
 This exposes the tarsal portion of the conjunctiva. To 
 
4 EXTERNAL EXAMINATION OF THE EYE 
 
 inspect the retrotarsal fold (and this is important in the 
 examination for trachoma) it is necessary to continue as 
 follows: Press the edge of the everted upper lid firmly against 
 the supraorbital margin with the thumb of the left hand; then 
 push the lower Ud upward over the cornea with the right in- 
 dex finger, at the same time exerting gentle backward press- 
 vu-e upon the eyeball (Fig. 5). Another method of ex- 
 posing the retrotarsal fold is to put the upper lid on the 
 stretch by drawing it downward and forward, and pressing 
 upon the skin above the tarsus with a flat, blunt instrument, 
 such as a squint-hook, until the fornix comes iato view. 
 
 Then we proceed to the eyeball and notice its situation in 
 the orbit, whether this is normal or whether the globe is 
 pushed forward (exophthalmos) or sunken (enophthalmos). 
 Its position in reference to the visual lines should be roughly 
 ascertained; we see whether the visual lines meet at the ob- 
 ject looked at, by directing the patient to gaze at a finger held 
 about a foot in front of the eyes; if they deviate, we inves- 
 tigate whether there is loss of motion in any direction (paral- 
 ysis), or absence of muscle-balance, either latent (heteropho- 
 ria) or manifest (strabismus), as explained in Chapter XXV. 
 We observe whether there is any oedema of the bulbar con- 
 junctiva (chemosis), or congestion of the anterior part of the 
 eyeball. If the latter is present, it should be 
 examined carefully, for the nature of this 
 injection points to the seat of inflammation 
 as explained on page 93, and illustrated on 
 Plate VII. 
 
 The cornea is next inspected, and may re- 
 veal inflammation, ulceration, vascularization, 
 opacities, or foreign bodies. As an aid, we 
 Fig. 6.— piacido's m^y now use a strong convex lens with which 
 to concentrate the light from the window, but 
 this method (oblique illumination) gives better results in the 
 dark room with artificial light, and is, therefore, described in 
 Chapter III. The corneal reflex derived from the window bars 
 
INSPECTION OF THE EYEBALL 5 
 
 gives us information concerning the curvature and smooth- 
 ness of this part of the eye. Placido's keratoscope (Fig. 6), a 
 target-like disc consisting of alternate black and white 
 circles, may be used. By causing the patient to look in dif- 
 ferent directions, every part of the 
 surface of the cornea is explored; dis- 
 tortion of the corneal reflection of the 
 circles or of the hues corresponding to 
 the window panes indicates a change ^ ^ 
 
 of curvature or roughness. A minute ^'°- 7.— Corneal Reflection 
 r • 1 J I-, 1 1 . , , . of Placido's Disc. A.Nor- 
 
 toreign body can often be detected m mai; b. distortion caused 
 
 this manner (Fig. 7) . •'y ^ foreign body on the 
 
 To bring an abrasion, infiltration, 
 or ulcer of the cornea more clearly into view, we may instil 
 a drop of 2 per cent, solution of fluorescein (p. 405), wash- 
 ing off the excess with water. Wherever the cornea is in- 
 filtrated or its epithelium is absent there will be a green 
 stain. 
 
 We often find evidences of previous ulceration of the cornea 
 in the form of opacities. When a corneal opacity is very faint 
 and cloud-like, it is called a nebula; when denser, a macula; 
 and when perfectly opaque and white, a leucoma (Figs. 147, 
 148, 149). 
 
 The sensitiveness of the cornea may be noted by touching it 
 gently with a thread or piece of soft paper, taking care not to 
 touch the hds or lashes. 
 
 When there is much irritation, spasm of the lids (blepharo- 
 spasm) prevents a proper examination. In such cases, the 
 instillation of a solution of cocaine or holocain will aid us in 
 exposing the eyeball. 
 
 In infants or very young children, when blepharospasm, 
 swelling, inflammation, or obstinacy prevents us from inspect- 
 ing the cornea in the usual way, the child is laid upon its back 
 across the nurse's lap, and its head is steadied between the 
 knees of the examiner who sits facing the nurse (Fig. 8). 
 Holding the child's hands, the nurse steadies the patient's 
 
6 
 
 EXTERNAL EXAMINATION OF THE EYE 
 
 body with her arms, allowing the legs to remain free, so that 
 when the child struggles it will expend its energy in motion 
 of the feet while the head remains the fixed point. Under 
 such circumstances the lids may usually be everted by pull- 
 ing upon them at a little distance from the margin. To 
 
 Method of Examining the Eyes of Infants and Young Children. 
 
 inspect the eyeball, we part the lids by placing our thumbs 
 at the edges, rolling in the latter somewhat and then separat- 
 ing, keeping close to the surface of the eyeball (Fig. 9). 
 Having exposed the eyeball, we may replace the thumb of the 
 right hand by the index finger of the left, thus leaving the 
 right hand free for other uses. The eye will usually be found 
 turned upward, hence the cornea will be hidden from view; 
 but after a minute it will appear in the palpebral aperture. 
 Care must be taken not to scrape the cornea and cause an 
 abrasion, nor to exert any pressure upon the eyeball, on ac- 
 
EXPOSURE OP THE EYEBALL 
 
 Fig. 9. — Method ol Exposing the 
 Eyeball. 
 
 count of the danger of perforation in case the cornea has 
 become weakened by ulceration. 
 
 It is sometimes necessary to use retractors (Fig. 10) in 
 order to separate the lids under such circumstances, and with 
 these the same caution is required 
 against wounding the cornea or 
 pressing upon the eyeball. 
 
 If the method of examining the 
 eyes of infants just described 
 should prove unsatisfactory, a 
 general anaesthetic must be em- 
 ployed. When forcibly separat- 
 ing the lids we must remember 
 that pent-up secretions are re- 
 leased suddenly and may squirt 
 into the eyes of the examiner. 
 Then we examine the anterior 
 chamber and notice its depth, whether normal, shallow, 
 or increased, and whether the aqueous Jiumor is clear; if the 
 _ latter is altered, we observe whether the exuda- 
 . , _^sists of pus (hypopyon), blood (hyphaema), 
 
 exudation, or the like. 
 The iris comes next. We observe its color, 
 smoothness, and thickness, whether its markings 
 are clearly defined or blurred (" muddy "), and 
 whether it is steady or tremulous during move- 
 ments of the eyeball. Adhesions to the cornea 
 (anterior synechiae) or to the capsule of the lens 
 (posterior synechiae) are looked for; these may 
 require the instillation of a mydriatic for their 
 detection. 
 
 Then we note the characteristics of the pupil: size, shape, 
 and position, and compare its size with that of its fellow; 
 also its reaction to light, and in accommodation and con- 
 vergence as explained on page 17.5. Behind the pupil 
 we see the central part of the anterior surface of the fens and 
 
 Fig. 10 
 
 Retractor 
 
 Lid 
 
EXTERNAL EXAMINATION OF THE EYE 
 
 observe its transparency or any abnormal condition which 
 may be present, such as cataract and deposits. To explore 
 the lens fully, dilatation of the pupil and artificial illumina- 
 tion are required. 
 
 Palpation gives us information regarding (1) the presence 
 or absence of sensitiveness in the ciliary region; (2) the degree 
 
 of hardness of the eyeball, and 
 (3) the existence of tumors and 
 swellings in and about the 
 orbit. 
 
 Ciliary Tenderness. — By ex- 
 erting gentle pressure upon the 
 sclera, just behind the cornea 
 (Fig. 11), as described below, 
 we may discover increased sen- 
 sitiveness of the cihary body; 
 this is an important symptom 
 of cyclitis. 
 
 Eyeball Tension. — To ascer- 
 tain the tension, we direct the 
 patient to look down, and then 
 gently palpate the sclera above 
 the cornea, by means of the 
 two index fingers placed upon 
 the upper lid (Fig. 11), just as in feeling for fluctuation in an 
 abscess, but pressing more downward than backward. We 
 estimate the degree of tension by comparison 'with the 
 other eye, if normal, or with another healthy eye. In- 
 crease of tension is a prominent S3'mptom of glaucoma; per- 
 forating wounds and degenerated conditions of the eyeball 
 cause diminished tension; alternations in tension are some- 
 times found in cyclitis. 
 
 Tension is expressed by the sign T. followed by n. when 
 normal, by + or — when increased or diminished, with nu- 
 merals indicating the degree of change, as follows: 
 
 Fig. 11. 
 
 -Testing the Tension of the 
 Eyeball. 
 
EYEBALL TENSION 
 
 9 
 
 T.n. = Tension normal. 
 
 T. + = Tension increased. T. — = Tension diminished. 
 
 T. + 1 = Appreciable hardness. T. — 1 = Appreciable softness. 
 
 T. + 2 f= Decided hardness. T, — 2 = Decided softness. 
 
 T. + 3 = Board-Uke hardness. T. - 3 = Eyeball very soft. 
 
 The degree of tension can be measured more accurately 
 with an instrument, the tonometer (Fig. 12), the model 
 of Schiotz being in general use; Gradle's 
 modification has the advantage of 
 greater convenience in application. 
 This instrument records the resistance 
 offered to definite weights used to pro- 
 duce an impress of the eye, by the 
 movement of a needle upon a scale. 
 The eye having been anaesthetized 
 with a 1-per-cent. solution of holocain, 
 the lower extremity of the tonometer 
 is' rested upon the centre of the up- 
 turned cornea. Different weights are 
 superimposed, depending upon the 
 tension; the deflection of the needle 
 indicates how many milfimeters of 
 mercury this corresponds to. The 
 normal tension varies from 15 to 25 
 mm. of mercury. 
 
 Thus we conduct that portion of 
 the objective examination for which 
 daylight furnishes suitable illumi- 
 nation. For more minute inspection 
 of the cornea, anterior chamber, iris, 
 and lens, as well as for examina- 
 tion of the vitreous and fundus, we resort to oblique illumina- 
 tion and the use of the ophthalmoscope in the dark room 
 (Chapter III.). 
 
 Fig. 
 
 12. — Tonometer of 
 Schiotz. 
 
CHAPTER II 
 
 SUBJECTIVE OR FUNCTIONAL EXAMINATION OF 
 THE EYE 
 
 The subjective examination, dependent upon the state- 
 ments of the patient, comprises the testing of the function 
 (vision or sight) of each eye separately. This function may 
 be subdivided into (1) the form sense; (2) the color sense; 
 and (3) the light sense. 
 
 The form sense is the faculty which the eye possesses of 
 perceiving the shape or form of objects, and is expressed as 
 acuteness of vision. The color sense is the power which the 
 eye has of distinguishing light of different wave lengths, i.e., 
 distinguishing colors. The light sense is the faculty of per- 
 ceiving different degrees of intensity of illumination (bright- 
 ness). We distinguish between a., central or direct, and b., 
 peripheral or indirect vision. 
 
 THE ACXJTENESS OF VISION 
 
 Central or Direct Vision. — When we wish to obtain 
 a distinct image; we look directly at an object so that the 
 image falls upon the macula lutea, the portion of the retina 
 which is adapted for the most acute vision; this constitutes 
 direct vision. The acuteness is tested both for distant 
 and for near vision. 
 
 Distant Vision. — In testing for distance a range of 20 feet 
 (6 meters) is selected, since rays of light from this distance 
 are practically parallel. For this purpose we make use of 
 Snellen's test types, which are constructed upon the following 
 principle: Each letter is inscribed within a square (Fig. 13) 
 which subtends a visual angle of 5' at the distance at which 
 the normal eye should distinguish the letter. The visual 
 angle is included between two lines drawn from the extrem- 
 
 10 
 
THE ACUTENESS OF VISION 11 
 
 ities of the object through the nodal point of the eye, which 
 is situated 15 mm. in front of the retina and 7 mm. behind 
 the cornea (Fig. 14). Each side of the square is subdivided 
 into five equal parts; the smaller squares 
 thus formed subtend a visual angle of 1', BH^^H 
 which is the minimum visual angle for the ^^^^^B 
 normal eye — that is, if two black objects on LL-H-i— i 
 a white ground are separated by a space r"'|^L|"~i 
 subtending a smaller angle, they will no 
 
 , , , , , Fig. 13.— Construe- 
 
 longer be seen separate, because the two tion of Snellen's 
 
 images will fall upon the same cone in the Test Types, 
 layer of rods and cones of the retina. In 
 order to subtend the same visual angle, the size of the let- 
 ters must increase the farther they are removed from the 
 eye (Fig. 14). 
 
 Snellen's Test T3^es consist of square-shaped letters ar- 
 ranged upon a chart, the size of the letters diminishing from 
 above downward. The height of each letter subtends a 
 visual angle of 5', the width of the component limbs a visual 
 angle of 1'. The uppermost letter is of such a size that it 
 
 Fig. 14. — The Estimation of the Size of Snellen's Test Types at Various Distances. 
 
 can be read at 200 feet; then follow rows of letters which 
 should be read at 100, 70, 50, 40, 30, 20, 15, and 10 feet 
 respectively (Figs. 15 and 16). 
 
 The acuteness of vision is expressed by a fraction, the 
 numerator of which corresponds to the number of feet sepa- 
 rating the patient from the chart (preferably 20 feet), and 
 the denominator to the number indicating the distance at 
 which the smallest letters seen should be read by the normal 
 
12 
 
 FUNCTIONAL EXAMINATION OF THE EYE 
 
 eye. If the patient's sight is normal, his acuteness of vision 
 will equal fj; this is expressed V. = |^ (or | if we use meters) . 
 If he can see only the third line from the top, V. = f f . If he 
 can not read more than the top letter, V. =-tuts- If he reads 
 some letters in the 50 line, but not all of this size, V. = |^ — or 
 7^ +■ Many persons, especially during youth, can read the 
 line which should be read at 15 feet, or even 10 feet, when 
 
 
 
 
 
 
 
 
 T 
 
 -D L 
 
 "T C E- 
 
 " X c V r ■» 
 
 " Z A O T H ■ 
 
 - r T E V L c ... 
 •« CLvroTSE .» 
 
 » EACrSLOt .»• 
 
 
 m 
 
 
 y«iixN» Trsi ivpfs 
 
 111 
 
 3 Ul 
 
 E iij a 
 
 E. 3 ui m 
 
 U 3 E m P) 
 
 u m E 111 3 e 
 
 E 3 m n u E u 
 
 
 T E 
 
 L E H 
 
 D O C V 
 
 ■ Z E A T P • 
 
 . r H L X D o .■■ 
 
 PDZTELr 
 
 
 
 
 
 
 
 
 
 Fig. 16.— Snellen's Test Fio. 16.— Snellen's Test Fig. 17.— Test Types for 
 Types. Usual Style of Types. White Letters Illiterates. 
 
 Chart. on a Black Ground. 
 
 placed 20 feet from the chart; the fractions in these cases 
 would be ff and i^. Sometimes the acuteness of %'ision is 
 expressed by 1 for H and by smaller fractions for reduced 
 sight, such as | for f^. 
 
 If the patient's vision is less than -jVd-, we reduce the dis- 
 tance from the chart. If he sees the largest letter at 8 feet, 
 V. = shi- If he cannot read the top letter at any distance, 
 
CENTRAL VISION 
 
 13 
 
 we record the distance in feet or inches at which he can 
 correctly count the examiner's fingers (extended) held against 
 a dark background; for example, V. = Fingers at one foot or 
 at 7 inches. If he has less sight than this, we move the hand 
 before the eye, and if he is capable of appreciating such move- 
 ments, we say he has " perception 
 of hand movements " at so and so jfo. 1. 
 many inches or feet. If vision is 
 still further reduced, we ascertain 
 whether he has perception of 
 light (P. L.) by alternately shad- 
 ing and exposing the eye by 
 means of the hand, or by throw- 
 ing light upon the eye with the 
 ophthalmoscope or lens in the 
 dark room, and noting whether 
 he indicates- the presence or ab- 
 sence of illumination. 
 
 Each eye is tested separately, 
 one eye being covered with a 
 card, or with the opaque disc 
 supported in the trial frame. 
 Daylight is the usual means of 
 illuminating the chart, but arti- 
 ficial light thrown directly upon 
 the test letters may be used. 
 The test types are hung opposite 
 a window, at about the level . of 
 the patient's eyes, and the pa- 
 tient is placed with his back to fig. 
 the source of illumination. 
 
 When the person is illiterate, 
 we employ a series of letters E, with sizes corresponding to 
 those of the Snellen types, in which the openings point 
 downward, upward, and to the right and left (Fig. 17) ; the 
 acuteness of vision is then fixed by the smallest row of 
 
 • •BDftgta Id maDiml aeEaiiatlaD of b coambt lort, tha 
 Ihborer hu IlltU opportnaitr (ithar to try or to miiana hii 
 argta of Tialon; hli ■l^ht, udIoh attacked br local InBam- 
 
 No. 2. 
 
 matory diseaaea or the conseqaences of const) - 
 tutipnal disorders, remains good, though iU 
 acuteness lacks that extreme development 
 
 No. 3. 
 
 which follows abundant use In 
 higher types of occupation. But 
 with the literary worker It Is dlfler- 
 
 No.4. 
 
 ent : keeping pace more or less 
 with mental activity, the eye 
 is constantly called upon for 
 
 No. 6. 
 
 action, in reading for infor- 
 mation and reference on the 
 one hand, in recording the 
 
 No. 6. 
 
 fruits of such occupation 
 on the other. Observation 
 has shown that deteriora- 
 
 No. 7. 
 
 tion in eyesight and 
 changes in the form, and 
 hence in the dioptric 
 
 18. — Jaeger's Test Types for 
 Near Vision. 
 
14 FUNCTIONAL EXAMINATION OF THE EYE 
 
 which the patient can correctly tell the direction in which 
 the figures are open. 
 
 In the case of children who have not yet leamt the alpha- 
 bet, we may employ a chart presenting the pictures of 
 common objects conforming in size to the standard angle. 
 
 Near Vision. — When in a state of rest, the eye is adapted 
 for parallel rays coming from a distant object. In order that 
 divergent rays from a near object shall be focussed on the 
 retina, there must be an increase in the refractive power of the 
 eye: this change is known as accommodation; it will be more 
 fully described in Chapter XXII. 
 
 The test types usually employed to determine near vision 
 consist of different sizes of ordinary printer's types; the finest 
 is nmnbered 1, successive numbers indicating coarser type. 
 They are known as Jaeger's test types (Fig. 18). 
 
 The patient should be placed with his back to the light, so 
 that the page is well illuminated, and each eye-tested sepa- 
 rately. His near vision is expressed by J., followed by the 
 number corresponding to the finest print which he can read; 
 thus, J. 3 means that the patient is able to read the third 
 
 paragraph. 
 
 THE FIELD OF VISION 
 
 Peripheral Vision (Indirect Vision) is exercised when the 
 image falls upon some part of the retina outside the fovea 
 centraUs; such vision is indistinct, but of great importance 
 for our guidance and safety. 
 
 The Field of Vision represents the limits of peripheral or 
 indirect vision; it is the space within which an object can be 
 seen while the eye remains fixed upon some one point. It 
 usually refers to one eye, the other being covered, and, when 
 not otherwise stated, applies to a white object. The field, can 
 be outlined roughly by the hand, more accurately by a piece 
 of chalk upon a blackboard, or a lighted candle, most exactly 
 by means of a perimeter. 
 
 The Hand Test. — The patient is turned with his back to the 
 Ught, and the examiner faces him at a distance of two feet. 
 
PERIPHERAL VISION 
 
 15 
 
 After covering one eye, the patient is directed to fix that eye 
 of the examiner, which is opposite; the examiner closes his 
 other eye. The hand with extended fingers is then moved 
 from various parts of the periphery inward, midway between 
 examiner and patient, and the latter indicates when he sees 
 the fingers. In this way the examiner can compare the pa- 
 tient's field with his own; if both be normal, patient and 
 examiner must see the fingers simultaneously. This is a very 
 simple and rapid method, and will reveal any large defect in 
 the field. Instead of the hand, a 1 cm. white knob upon the 
 end of a black rod may be used to measure the field in like 
 manner. 
 
 The Blackboard Test gives us an approximately correct 
 graphic representation. The patient is placed 12 inches in 
 front of a blackboard, upon which we mark a cross to serve as 
 the point of fixation. A piece of chalk is now gradually 
 brought from the periphery toward the centre, and the patient 
 
 indicates when he sees 
 
 it in the several direc 
 tions. These points 
 are marked, and by 
 connecting them an 
 outline of the field is 
 obtained. 
 
 The Candle Test — 
 When the patient is 
 no longer able to see 
 the hand, we make 
 use of a lighted can- 
 dle or a small electric 
 lamp, conducting the 
 test in the dark room, 
 
 covering the eye not under examination and, while moving 
 the light about through the field of vision, requiring the 
 patient not only to tell when the light is exposed or shaded 
 but also where he sees it. 
 
 Fig. 19. — The Perimeter. 
 
16 FUNCTIONAL EXAMINATION OF THE EYE 
 
 The Perimeter (Fig. 19) furnishes the most exact method. 
 It consists of a metallic semicircle or quadrant, which can be 
 revolved so as to take the direction of any meridian. This 
 arc is marked in degrees, corresponding to the middle point 
 and 90 to either extremity. The patient's head is supported 
 upon a chin-rest, one eye covered, and the other fixed upon 
 a white spot located at the centre of the arc. The test ob- 
 ject, a 10 mm. white square, is carried along the inner surface 
 of the arc, either upon a black movable disc attached to the 
 instrument or upon the end of a black rod. The points 
 where the test object is first seen in the different principal 
 meridians are marked upon diagrams of the normal field; 
 the lines connecting these form the boundary of the field. 
 
 The Extent of the Normal Form Field with a 10 mm. white 
 test object at the usual distance of J^ m. is as follows: 
 Outwards, 90° (or more); upwards, 55°; inwards, 60°; down- 
 wards, 70° (Fig. 20) . The restriction in the field upward and 
 inward is due to interference from the nose and brow, and 
 because the percipient layers of the retina do not extend 
 as far forward on the temporal as on the nasal side. 
 
 Pathological Alterations in the Field of Vision. — These 
 consist of limitation and defects. Limitations may assume 
 the form of contraction evenly in all directions {concentric), 
 irregular contraction, or loss of part of the field on one 
 side or the other. 
 
 Concentric contraction affects all pa-rts of the periphery alike; 
 when considerable, nothing but central vision may remain 
 (Fig. 248) ; such contraction with preservation of good central 
 vision is met with, for instance, in retinitis pigmentosa. The 
 contraction may affect only or especially one side of the 
 periphery; in such cases we speak of temporal or nasal con- 
 traction (Fig. 188), or upper or lower contraction. When 
 one-half of the field is absent (Fig. 251), this constitutes 
 hemianopsia (p. 289). Sector-shaped contractions some- 
 times exist; the defect then has the shape of a triangle the 
 base of which is peripheral. Certain affections produce 
 
ALTERATIONS IN THE FIELD OF VISION 
 
 17 
 
 characteristic contraction of the visual field; for instance, in 
 atrophy of the optic nerve the contraction is concentric; 
 in glaucoma, it is usually greatest on the nasal side. 
 
 A scotoma is a defect within the visual field. A physi- 
 ological scotoma is Mariotte's blind spot situated about 
 15° to the outside 
 of the point of fix- 
 ation, corresponding 
 to the entrance of 
 the optic nerve (the 
 black spot in Fig. 
 20). According to 
 their situation, we di- 
 vide scotomata into 
 central, paracentral, 
 ring, and peripheral. 
 A central scotoma cor- 
 responds to the point 
 of fixation (Fig. 245); 
 when marked, it in- 
 terferes with or abol- 
 ishes central vision 
 altogether; the scotoma accompanying hemorrhage at the 
 macula furnishes an example. A paracentral scotoma is sit- 
 uated near the point of fixation and a ring or annular sco- 
 toma encircles this point. Peripheral scotomata cause little 
 disturbance of sight and may exist without the patient's 
 knowledge, especially when situated far from the point of 
 fixation; disseminated choroiditis furnishes examples of scoto- 
 mata of this sort (Fig. 171). 
 
 Scotomata may be positive, when the patient sees them as 
 black spots in his field, or negative, when they exist as defects 
 in the visual field, but are not perceived by the patient until 
 the visual field is examined. Positive scotomata are due to 
 changes in the media or in the retina. If the opacities exist 
 in the vitreous, the scotomata are motile; muscae volitaEftes 
 
 Fig. 20. — Normal Fields for White and (or Colors 
 CBlue, Red, and Green), with a 10 mm. teat object. 
 
18 FUNCTIONAL EXAMINATION OF THE EYE 
 
 represent one variety of defects of this sort. Negative scoto- 
 mata may be absolute, when perception of light is entirely 
 lost over the defective area, or relative, when there is only 
 diminished perception of light, or loss of perception of certain 
 colors over this area. Toxic amblyopia gives us an example 
 of a scotoma which is central, relative, and often negative. 
 For the detection of scotomata, white and colored test 
 objects having a diameter of 2 mm. should be moved in 
 different meridians, and the spots where the object dis- 
 appears or loses its color and then reappears or regains its 
 color noted upon a chart. Such test is most conclusive when 
 made upon a black screen at a distance of 2 meters so as to 
 furnish a larger projection of the defect. 
 
 THE COLOR SENSE 
 
 The color sense as a whole (i.e., the faculty of distinguish- 
 ing different colors) is investigated by the methods described 
 in Chapter XX. We distinguish between central and peri- 
 pheral perception of color. The former is tested by the ex- 
 hibition of samples of colored wool as described on page 282, 
 the latter by small objects, such as squares of colored paper 
 or small colored knobs 5 to 10 mm. in diameter, which are 
 moved from the periphery toward the centre, on the perimeter, 
 or in the coarser methods of testing the field. 
 
 The Field for Colors is smaller than that for white, but has 
 the same general shape. It varies for different colors and 
 its extent is influenced by the size, brightness, and saturation 
 of the test object; that for blue is the largest, next comes 
 red, while green has the smallest field. In rough dimensions 
 the field for blue is 10° smaller than that for white; red 10° 
 less than that for blue; and green contracted 10° as compared 
 to red. The limits (given in Fig. 20) correspond to the 
 points at which the colors are recognized, not to those -points 
 at which merely the presence of a moving object is perceived. 
 The examination of the color fields is of considerable impor- 
 tance, since we frequently find that contraction of the field 
 
THE LIGHT SENSE 19 
 
 for colors exists at an earlier period than that for white. It 
 is a more delicate test, and detects diminution of visual 
 power before it has become sufficiently pronounced to affect 
 the field for white (form). 
 
 THE LIGHT SENSE 
 
 The light sense is the power of perceiving gradations in 
 intensity of illumination (brightness); it is tested by means 
 of an apparatus known as a photometer. We determine either 
 the lowest limit of illumination with which an object is still 
 visible (light minimum = 11. M.), or the smallest difference in 
 illumination which can be appreciated (light difference^= L.D.). 
 The estimation of the light sense is of some practical value in 
 differential diagnosis of certain diseases of the fundus, though 
 not generally made use of. Diminution in the light sense is 
 not always proportionate to reduction in the acuteness of 
 vision. Marked reduction of the light sense is seen in cases 
 which are accompanied by night blindness — retinitis pig- 
 mentosa, for instance. 
 
 The examination of the motility of the eye is described in 
 Chapter XXV. 
 
CHAPTER III 
 
 OBJECTIVE EXAMINATION OF THE EYE CON- 
 DUCTED IN THE DARK ROOM: OBLIQUE IL- 
 LUMINATION AND THE OPHTHALMOSCOPE 
 
 The Examination in the Dark Room comprises the follow- 
 ing steps, which are best taken in the order given: 
 
 1. Oblique illumination, for the physical examination of the 
 anterior portions of the eyeball. 
 
 2. Examination with the ophthalmoscope at a distance, for 
 exploring all the media of the eyeball. 
 
 3. The indirect method of ophthalmoscopy, for examining 
 the fimdus, giving an inverted picture of low magnification. 
 
 4. The direct method of ophthalmoscopy, for examining the 
 fundus, giving an erect picture of greater magnification. 
 
 The examining-room should have dark walls, and all light 
 excepting that made use of by the surgeon should be excluded. 
 The source of illumination usually preferred is an Argand gas 
 burner, or an electric light with frosted globe, upon a " uni- 
 versal bracket," which permits the flame to be placed on 
 either side of the patient, and to be raised or lowered at will. 
 Patient and examiner may be either standing or seated. 
 
 OBLiaTTE ILLUMINATION 
 
 Oblique (lateral or focal) illumination furnishes a very 
 valuable means of minutely exploring the cornea, anterior 
 chamber, iris, and lens. By means of a strong convex lens of 
 two- or three-inch focus, light is concentrated upon the eye in 
 such a manner that the apex of the cone of light corresponds 
 to the part to be examined (Fig. 21). The source of illumi- 
 nation should be about eighteen inches to the side of the 
 patient, several inches in advance, and on a level with the 
 eye. The lens is grasped by its margin between the thumb 
 
 20 
 
OBLIQUE ILLUMINATION 
 
 21 
 
 and index finger, held so that its surfaces are at right angles 
 to the direction from which the light proceeds, and steadied 
 by means of the little finger placed against the side of the 
 patient's face. After having examined one eye, without 
 removing the supporting finger, we turn the patient's head 
 slightly toward the light and illuminate the other eye. The 
 flame may be placed on either side; if on the patient's right. 
 
 mppiiB 
 
 M^ 
 
 ^ 
 
 w^^ 
 
 w- 
 
 
 ;W 
 
 11;; 
 
 
 
 £ 
 
 ^ 
 
 ^ 
 
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 4 
 
 ^HP*lLj" 
 
 ^^A 
 
 
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 w 
 
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 '•1 
 
 Hi 
 
 
 IK 
 
 w 
 
 d 
 
 J 
 
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 Al 
 
 
 Fig 21. — Oblique Illumination. 
 
 we use the left hand for holding the lens ; if on the left, we 
 use the right hand. After having examined the cornea the 
 lens is brought nearer to the eye, so that the apex of the cone 
 of light corresponds to the deeper structures which we wish 
 to explore. 
 
 With a strong second convex lens held at its focal distance 
 (two or three inches) in front of the patient's eye, we can 
 magnify the illuminated area and thus obtain greater 
 detail. 
 
 Opacities of the cornea, aqueous, or lens, seen by oblique 
 illumination, appear as grayish or white spots upon the black 
 ground of the pupil (Figs. 26, 28, 30, 32, Plate II). 
 
22 
 
 OBJECTIVE EXAMINATION OF THE EYE 
 
 THE OPHTHALMOSCOPE 
 
 The invention of the ophthalmoscope (Fig. 22) by Helm- 
 holtz in 1851 was not only an epoch in ophthalmology, but 
 constituted an important event in general medicine. Its use 
 enables us to explore the interior of the eye and thus diagnose 
 lesions concerning which we had previously little knowledge 
 
 Fig. 22. — The Ordinary or Reflecting Ophthal- 
 moscope, Author's Model. A, Rear side; 
 B, Lens disc; C, Mirror side. 
 
 Fig. 23.— The Electric Ophthal- 
 moscope, Author's Model. A, 
 Luminous side; £, Section. 
 
 during life. Of equal importance is the power of recognizing 
 changes in the fundus which constitute valuable signs in the 
 diagnosis of systemic disease. 
 
 The essential portion of this instrument is a perforated 
 mirror. This is mounted upon a convenient handle and sup- 
 plemented behind by a disc containing convex and concave 
 lenses. The mirror serves to reflect light into the interior of 
 the eye, while the aperture allows a portion of this light, after 
 returning from the patient's eye, to pass into that of the 
 observer. The mirror commonly employed is concave, of 
 
THE OPHTHALMOSCOPE 23 
 
 about ten inches focus, either circular or of the form of a 
 parallelogram, which allows it to be tilted to the right or left. 
 The lens disc supports a series of lenses arranged successively 
 from weaker to stronger. Any of these can be brought 
 opposite the perforation in the mirror by means of the finger 
 applied to the milled edge of the disc. Opposite each lens 
 is a number indicating its strength in diopters. 
 
 The Electric Ophthalmoscope (Fig. 23) is self-luminous, a 
 small electric lamp being placed within the handle, and its 
 rays reflected into the patient's eye, by means of a reflector 
 placed at a suitable angle. The lighting current is supplied 
 either by a battery in the handle, a portable storage battery 
 connected by cords, or the house current with interposition 
 of a rheostat. Such instrmnents (introduced by Dennett) 
 are in common use, not only in the office, but especially at the 
 bedside and with restless infants and children; the beginner 
 will find the electric instrument much easier than the or- 
 dinary variety. The May Electric Ophthalmoscope has many 
 advantages, including improved illumination obtained from 
 a combination of converging lenses and a reflecting prism, 
 so that there is neither reflex nor shadbw and a very satis- 
 factory view of the fundus is obtained with the utmost ease; 
 furthermore, the instrument is indestructible, since the 
 usual fragile mirror is replaced by a metal-encased solid re- 
 flector. 
 
 THE OPHTHALMOSCOPIC EXAMINATION 
 
 Before attempting to see the fundus, we must explore the 
 merfm. This preliminary step is important, since it will ex- 
 plain blurring in the picture obtained by subsequent methods, 
 or failure to see the fundus when changes in the media 
 exist. One mode of obtaining such information, oblique 
 illumination, has already been described; it is parti ciilarly 
 applicable to the anterior media. A second method is 
 
 Examination with the Ophthalmoscope at a Distance.— 
 This method explores all the media — cOrnea, aqueous, lens, and 
 
24 OBJECTIVE EXAMINATION OF THE EYE 
 
 vitreous. The light is reflected from the mirror into the eye, 
 and, returning from the background, traverses the media 
 before reaching the eye of the examiner through the aperture 
 in the mirror. 
 
 The source of illumination is placed on either side of the 
 patient, on a level with the eye and several inches to the side 
 and behind, so that the light strikes the patient's temple, 
 leaving his face in darkness. The patient faces the examiner, 
 the latter standing or sitting directly in front. The ophthal- 
 moscope is held in front of either eye of the observer, so that 
 he can look through the perforation, and is steadied against 
 the side of the nose and supraorbital margin. The distance 
 between patient and examiner is about fifteen inches. 
 
 From the mirror the light is reflected into the eye of the 
 patient. Reaching the background, it is reflected and now 
 has an orange-red color imparted by the choroid layer; this 
 tinted light returns through the patient's eye and enters the 
 eye of the examiner by means of the aperture in the mirror. 
 The exact tint varies with the color of the background of the 
 individual, depending upon the abimdance of choroidal and 
 retinal pigment; henCe it is. brighter in persons of light com- 
 plexion, and darker in others. It is also influenced by the 
 amount of illumination, and consequently the reflex is 
 brighter when the pupil is dilated. The patient is told to 
 move the eyes in various directions, and in this manner all 
 parts of the media are explored. 
 
 In the normal eye a homogeneous orange-red reflex (fundus 
 reflex) is obtained (Fig. 24, Plate II). If any details of the 
 vessels of the fundus are seen, the eye is ametropic (Fig. 25, 
 Plate II). If, when the observer moves his head from side to 
 side, these vessels appear to move in the same direction, the 
 eye is hyperopic; if in the opposite direction, it is myopic. 
 
 If opacities exist in any of the media, they will appear as 
 dark or black spots upon the colored background of the pupil. 
 They are dark because they intercept a certain part of the 
 light (Figs. 27, 29, 31, 33, Plate II). Opacities of the media 
 
PLATE II 
 
 m 24 -Xoiinal I undus Tic n( 
 Oplll h ilriKis( op. il I Disl iTii I 
 
 Fr(;.25. — FiiiuUis Kcflrx in ,V]7lctro|)ia. 
 ()l>hl.h;iliii(isco|ji' al a Distanci', 
 
 -1 
 
 i'^^'-^ju 
 
 Fiii. 20. — Opacity of tho Cornea: 
 <H>liqu(' lllanlinatioil. 
 
 Fit;;. 27. — Opacit.\- of the C^ornoa; 
 < >|)i)tllalrn(jscopr at tt DistantM^ 
 
 2S. — Senile C\itartiel (Cortical) 
 Obliqtie Ultiniination. 
 
 I, 
 
 Fi(.i. 2!) — Senile Cataract (Cortical) 
 Ophthalmoscope at a Distance 
 
 no 
 
 M ^cn li Cjtai i( I iVuc liar i 
 ObhciLU llkmnn aion 
 
 1 II I ^ ml ( It II Kt \ii( li I 
 ijplu 1 tiuio^MJiK It d Di-^tai(( 
 
 Fig. 
 
 32. — Lamellar Catai-act: Ob- 
 li(|ue Illumination. 
 
 Fig. 33. — Lamellar Cataract; Oph- 
 thalmoscope at a Distance. 
 
 Figs. 24-33. — Examination of the Media with Oblique Illumination and the 
 Ophthalmoscope at a distance. 
 
EXAMINATION OF THE MEDIA 25 
 
 may be either fixed, in which case they move only with the 
 eye, or movable (floating), when they float about after the 
 eye has been rapidly moved and then suddenly stopped: the 
 latter occur only in an abnormally fluid vitreous. 
 
 The exact situation of opacities of the media can often be 
 estimated by oblique illumination. Another method consists 
 in noting the displacement of the opacity with regard to the 
 pupil, when the observer's head is moved slowly from side to 
 side. When there is no apparent motion of the opacity, it is 
 in the plane of the iris; when it appears to move in the oppo- 
 site direction, it is in front; and when in the same direction, 
 it is behind this plane. A third method is based upon the 
 relationship of the motion of the opacity to that of the eyeball. 
 If, when the patient moves his eye, the opacity moves with 
 (in the same direction as) the eye, it must be in front of the 
 centre of rotation of the globe (which corresponds to the ante- 
 rior portion of the vitreous, about 10 mm. in front of the 
 retina); if it moves in the opposite direction, it must be 
 behind this point; if it has no motion, it must be exactly at 
 the centre. In both of these tests the greater the apparent 
 motion the more removed is the opacity from the plane of the 
 iris and the centre of rotation of the globe respectively. 
 
 Additional detail of changes in the media and iris may be 
 obtained by placing strong convex lenses (from 5 to 20 D.) in 
 the sight-hole of the ophthalmoscope, gradually approaching 
 the eye as the strength of the lenses is increased, so as to 
 bring the examined part into focus. 
 
 Having ascertained the condition of the media, we proceed 
 to examine the fundus. The expert may succeed with a pupil 
 of natural size; but it is often wise, and not infrequently 
 necessary, to dilate the pupil. Moderate dilatation is secured 
 by instilling one drop of a 4-per-cent. solution of cocaine; 
 after 15 minutes the pupil will be of sufficient size, and the 
 effects will pass off in half an hour, causing little discomfort. 
 A 5-per-cent. solution of euphthalmin acts more energetically 
 and the effects pass off within a few hours. Greater dilatation 
 
26 OBJECTIVE EXAMINATION OF THE EYE 
 
 follows the instillation of one drop of a 2-per-cent. solution 
 of homatro-pine, or of a mixture of 2-per-cent. homatropine 
 and 1-per-cent. cocaine; these cause mydriasis in from 20 
 to 30 minutes, and the effects last from 24 to 36 hours. 
 
 There are two methods of examining the fundus: (1) the 
 indirect, (2) the direct. 
 
 The Indirect Method of Ophthalmoscopic Examination. — 
 With the indirect method we obtain an inverted image of the 
 fundus, magnified about four diameters. The source of illumi- 
 
 FlG. 34. — Indirect Method of Ophthalmoscopic E.tamination. 
 
 nation is in the same position as when we examine the media 
 — behind, to the side, and on a level -ndth the ej^e — and the 
 examiner and patient retain the same relative positions. In 
 the aperture of the ophthalmoscope we place a 3 or 4 D. 
 convex lens, which enables the examiner to obtain a clear 
 image with his accommodation at rest. Placing the ophthal- 
 moscope before either eye, at a distance of about 15 inches 
 from the patient, we obtain the fundus reflex. A strong con- 
 vex lens of about two inches focus (called the objective lens) 
 is now held at about its focal distance in front of the eye to 
 be examined. This lens is grasped at its edges by the thumb 
 and index finger of the left hand and steadied by placing one 
 of the other fingers against the forehead of the patient (Fig. 
 
INDIRECT METHOD OF OPHTHALMOSCOPY 27 
 
 34). If a clear view of some part of the background is not 
 obtained, we vary the distance from the patient by slowly 
 moving the head backward or forward, until there appears 
 a distinct aerial, inverted image of the fundus at a short 
 distance in front of the lens, corresponding to its focus. 
 
 After having seen the right fundus, we proceed to the 
 examination of the left, without making any change in the 
 position of the light, ophthalmoscope, patient, or examiner. 
 We merely move the lens so as to cover the patient's left eye, 
 now steadying it with the middle finger placed upon the 
 forehead; the little and ring fingers are flexed into the pabn 
 of the hand, so that they will not obstruct the right or free 
 eye of the patient and thus prevent him from gazing in any 
 direction which we indicate. In the examination of the left 
 eye we may, if we prefer, hold the ophthalmoscope in the 
 left hand and the lens in the right. 
 
 We always begin the examination by looking for the 
 entrance of the optic nerve (the disc or papilla), this being the 
 most prominent feature of the background. The optic-nerve 
 entrance is a little to the iimer or nasal side of the visual axis; 
 hence, in order to bring it into view, it is necessary to direct 
 the patient to move the eye in somewhat, which will rotate the 
 posterior pole of the eyeball outward. When we are directly 
 in front of the patient, this is accomplished by causing him to 
 look over our right shoulder, on a level with the upper border 
 of the ear, when we examine the right eye, and over our left 
 shoulder on a corresponding level, when we examine the 
 left eye. 
 
 To see the parts surrounding the disc, we move the lens or 
 the head slightly in various directions, always remembering 
 that the image is inverted, and that it moves with the leits, 
 but in the opposite direction to that taken by the head. More 
 peripheral parts are brought into view when the patient moves 
 his eye up, down, to the right, and to the left. 
 
 When the patient looks directly at the ophthalmoscope, it 
 brings the macula into view; but since he must accommodate 
 
28 OBJECTIVE EXAMINATION OF THE EYE 
 
 when fixing so near an object, the pupil will contract. On 
 this account it is well to dilate the pupil when we wish to 
 get a view of the macular region with the indirect method. 
 
 The beginner may encounter a number of difficulties in 
 using the indirect method. He may have trouble in bringing 
 the disc into view, because the patient persists in watching the 
 ophthalmoscope instead of looking across the examiner's 
 shoulder. Owing to defects in the manufacture of the instru- 
 ment, there are often very confusing reflexes from the margins 
 of the sight-hole and perforation of the mirror. There is fre- 
 quently a very annoying reflection of the flame from the cornea 
 or from the sqrfaces of the lens which we hold before the 
 patient's eye. These reflexes may be obviated by 'a slight 
 inclination of the lens, a change in the angle of the mirror, or 
 a little variation in the position of the examiner or source of 
 illumination, which experience alone will teach us. 
 
 The Direct Method of Ophthalmoscopic Examination. — 
 With the direct method we obtain an erect picture of the 
 fundus magnifled about fourteen diameters. 
 
 The examiner sits or stands to the side of and facing the 
 patient (Fig. 35). The ophthalmoscope is supported as in 
 previous methods, and brought directly in front of the pa- 
 tient's eye as close as possible. There should not be a greater 
 distance than an inch between the eye of the patient and that 
 of the observer. The light occupies about the same position 
 as in previous methods. 
 
 When we examine the right eye, the examiner and the light 
 must be on the right side, and consequently the ophthalmo- 
 scope must be placed before the right eye of the observer. 
 When the left eye is being examined, the light and examiner 
 must be to the left, and the observer must use his left eye. 
 When the ophthalmoscope is provided with a tiltiiig mirror, 
 the surface of the latter must be turned toward the source of 
 illumination. 
 
 When both examiner and patient are emmetropic, and both 
 relax their accommodation, the observer looks through the 
 
DIRECT METHOD OF OPHTHALMOSCOPY 
 
 29 
 
 sight-hole and obtains a clear view of the fundus without any 
 lens. The patient is told to look at the opposite wall, directly 
 forward, over the shoulder of the examiner. This brings the 
 disc into view. The parts around the disc are next examined. 
 The periphery of the fundus is brought into view when the 
 patient looks in various directions. The macular region is 
 found to the outer side of the disc, the distance corresponding 
 
 Fig. 35. — Direct Method of Ophthalmoscopic Examination. 
 
 to about twice the diameter of the papilla. When the pupil 
 has been artificially dilated so that it cannot contract in ac- 
 commodation, the macula can also be brought into view by 
 directing the patient to look into the aperture of the mirror. 
 
 The size of any particular lesion is compared with that of 
 the disc (disc-diameters) . Changes in the level of the fundus 
 (elevations, depressions, new growths) are measured in diop- 
 ters; an elevation of 1 mm. corresponds to 3 D. 
 
 The beginner is often annoyed by reflexes from the cornea 
 and from the margins of the sight-hole and mirror perforation. 
 The former can be obviated by a slight change in the angle of 
 the mirror, the position of the examiner or that of the light; 
 the latter are due to defects in the ophthalmoscope. 
 
30 OBJECTIVE EXAMINATION OF THE EYE 
 
 If the observer he ametropic, he must either wear his correct- 
 ing distance glasses or have a special correcting lens fitted 
 behind the aperture, or he may rotate his correcting lens 
 before the aperture from one of those contained in the disc of 
 the instrument. When the patient is ametropic, a suitable lens 
 must be rotated into place behind the aperture; if he is my- 
 opic, this will be the weakest concave lens, and if hyperopic, 
 the strongest convex lens, which will give a distinct picture. 
 This gives an indication of the manner in which the direct 
 method is employed for the estimation of errors pf refraction. 
 
 The emmetropic observer will be unable to obtain a distinct 
 view of the fimdus of a myopic eye, by the direct method, 
 without inserting a concave lens. He can examine a hyper- 
 opic eye either by putting up a convex lens or by using his 
 acconmaodation. But in the direct method the observer must 
 learn to relax his accommodation. The beginner often finds 
 this difficult, since he cannot forget that he is looking at a 
 very near object, and he accommodates accordingly. He is 
 very apt to place a concave lens of about 4 D. in the sight- 
 hole ,tp neutralize the effects of such efforts, even though the 
 patient has no myopia. Relaxation of accommodation is ab- 
 solutely indispensable in using the direct method for the pur- 
 pose of estimating errors of refraction. It is encouraged by 
 keeping both eyes open and looking in the distance with the 
 uncovered eye. 
 
 The Indirect and Direct Methods Contrasted. — The in- 
 direct method gives us a larger field, though a smaller magnifi- 
 cation, and hence presents a general view of the background, 
 which is inverted. It can be used successfully independent of 
 errors of refraction in the patient's eye. On account of 
 greater illinnination we are often able to get details of the 
 fundus, even when slight opacities of the media exist. 
 
 The direct method, on the other hand, gives us an erect pic- 
 ture, which is more highly magnified, though a smaller por- 
 tion of the field is seen at a time; hence it permits of more 
 minute exploration of particular parts to which our attention 
 
THE OPHTHALMOSCOPIC EXAMINATION 
 
 31 
 
 has been directed by the indirect method. It is also the 
 method of using the ophthalmoscope for the estimation of 
 errors of refraction. 
 
 Theory of the Ophthalmoscope. — ^As ordinarily seen, the 
 pupil appears black because the light which leaves it is nec- 
 
 FlG. 37. 
 
 The Direct and Indirect Methods of Ophthalmoscopy Contrasted. The Picture of the 
 Fundus Obtained by the Direct Method (Fig. 36) is Erect and Highly Magnified. 
 That Obtained by the Indirect Method (Fig. 37) is Inverted and Less Magnified. 
 
 essarily reflected in the direction from which it came. If the 
 eye of the observer be placed so as to intercept the returning 
 rays, the interior of the observed eye will appear illuminated. 
 With the ophthalmoscope light is reflected into an eye under 
 examination, and the observer's eye is placed in the path of 
 the returning rays and receives some of these through the 
 perforation in the mirror. 
 
 Fig. 38 explains the iUumination of the interior of the eye with the 
 ophthalmoscope at a distance. E represents the eye of the examiner 
 and P that of the patient. Divergent rays of Ught, proceeding from 
 the Argand burner L, strike the ophthahnoscopic mirror O, are reflected 
 
32 OBJECTIVE EXAMINATION OF THE EYE 
 
 and made convergent, passing into the eye P, crossing in the vitreous, 
 and illuminating the fundus between A and B. From any point of this 
 illuminated area, C for instance, rays are reflected, pass out of the 
 eye, being made parallel by its refracting apparatus, and proceeding, 
 
 Fig. 38. — Ophthalmoscopic Examination at a Distance. 
 
 pass through the aperture of the mirror O into the eye of the examiner 
 E. The dioptric apparatus of E brings these rays to a focus on the 
 retina, and they form at C an image of C. 
 
 Fig. 39 explains the indirect method. From L divergent rays pro- 
 ceed to the mirror O, are reflected and made convergent, passing into 
 the examined eye P, crossing in the vitreous. They illuminate the 
 
 Indirect Method of Ophthalmoscopic Examination. 
 
 fundus between A and B. Prom any portion of this illuminated area, 
 C D for instance, rays are reflected, and, passing out of the eye, are 
 rendered parallel by its refracting apparatus. They fall upon the 
 convex lens (L) and are brought to a focus a C D', forming an 
 enlarged, inverted image in the air at the focus of the lens (L), which 
 image can be seen by the eye of the examiner E. 
 
PLATE in 
 
 Pig. 41. — Normal Fundus. Average Tint. 
 
 Fin. 42.— Normal Fundus in a Person of Light 
 Complfixion 
 
THE FUNDUS OCULI 33 
 
 Fig. 40 illustrates the direct method. Divergent rays proceeding 
 from L to the mirror O are reflected and made convergent, passing 
 into the examined eye P, crossing in the vitreous. The fundus from 
 A to B is hghted up. From any portion of this illuminated area, C D 
 for instance, rays are refliected, pass out of the eye P, being made 
 
 Fig. 40. — Direct Method of Ophthalmoscopic Examination. 
 
 parallel by its dioptric apparatus, through the perforation of the mirror 
 O, into the eye of the examiner E. Here they are brought to a focus 
 on the retina. They are convergent, and, being prolonged backward, 
 form a magnified and erect image of C D, behind the eye of the 
 patient P, at C D'. 
 
 The Normal Fundus. — The normal fundus exhibits a great 
 many variations in details. It presents an orange-red surface, 
 upon which we distinguish the disc, the blood-vessels, and the 
 macula (Plates III, IV, V). 
 
 The Disc (Papilla) represents the entrance of the optic 
 nerve; it is usually circular, but sometimes oval in form. Its 
 color is light pinkish, more pronounced over the inner half, 
 the outer portion being paler. The disc is much lighter in 
 color than the rest of the fundus, and is separated from ad- 
 jacent portions by a sharply defined margin, especially at the 
 outer side. This margin often presents two rings; an inner, 
 the scleral (s. Fig. 43), of white color, formed by exposure of 
 the sclera when the opening in the choroid is larger than that 
 in the sclera, and an external ring, the choroidal (c. Fig. 43), 
 of dark color, formed by an accumulation of pigment at the 
 
34 
 
 OBJECTIVE EXAMINATION OF THE EYE 
 
 margin of the aperture through which the optic nerve passes. 
 This pigmented ring may be complete or incomplete; in the 
 latter case it is generally found at the outer border. The 
 margins of the normal disc are occasionally slightly indistinct, 
 especially above and below; this appearance is sometimes 
 
 seen in hyperopia eyes of young 
 subjects, and mUst not be mis- 
 taken for neuritis. 
 
 The centre of the papilla pre- 
 sents a funnel-shaped depression 
 (E, Fig. 43, Fig. 46, Plate V) 
 formed by the separation of the 
 nerve fibres; this appears whiter 
 than the rest of the disc; it is 
 known as the physiological de- 
 pression or cup. It may be 
 comparatively large and occupy 
 one-half or more of the disc, but 
 never the entire papilla, in 
 which respect it differs from the 
 pathological excavations of 
 glaucoma and of optic-nerve 
 atrophy (Figs. 185, 186, 187). 
 At the bottom of this physiolog- 
 ical excavation, when marked, 
 we frequently see grayish spots; 
 these represent the openings in the lamina cribrosa, the con- 
 nective-tissue layer through which the fibres of the optic 
 nerve pass (Fig. 46, Plate V). 
 
 The Central Artery and Vein of the optic nerve (a and v, 
 Fig. 43) pass along the inner wall of the excavation, and 
 upon reaching the surface of the disc usually divide into supe- 
 rior and inferior divisions; each of these soon divides and 
 subdivides, giving off rtasal and temporal branches; from these, 
 smaller twigs are derived which become terminal and do not 
 anastomose. Small branches are often given off from the 
 
 Fig. 43. — ophthalmoscopic View and 
 Longitudinal Section of the Disc, 
 a. Central artery; i;, central vein; 
 E, physiological excavation; 3, 
 scleral ring; c, choroidal ring; t, 
 retina; ch, choroid; acl, sclera. 
 
PLATE IV 
 
 Fig. 44.— Normal Fundus in an Individual of 
 Dark Complexion. 
 
 Fig. 45.— Opaquf Nerve Fibres. 
 
THE OPHTHALMOSCOPIC EXAMINATION 35 
 
 main trunks and pass across the disc. The macular region is 
 devoid of larger vessels, though finer branches are seen to 
 approach this area. The arteries are readily distinguished 
 trom the veins by their smaller calibre, bright red color, and 
 straighter course; they present a bright reflex rurming along 
 the centre. The veins are of greater thickness, of a darker red 
 color, more tortuous, and the light-streak is fainter. Arteries 
 and veins usually follow the same course. The veins some- 
 times present a distinct pulsation, most marked where the 
 central trunk appears on the disc, and increased by pressure 
 upon the eyeball; this is physiological. Pulsation in the 
 retinal arteries, on the other hand, is pathological, and occurs 
 in glaucoma and in cardiac disease. 
 
 The Retina itself is transparent. The color of the back- 
 ground is derived from the choroidal vessels, and modified by 
 the pigment-epithelium layer of the retina and the pigment of 
 the choroid. It is bright orange-red in persons of fair com- 
 plexion, while in darker individuals it has a deeper, brick-red 
 color. The fundus presents a granular or stippled appear- 
 ance, caused by the pigment-cells. When the pigment- 
 epithelium layer of the retina is well developed, the choroidal 
 vessels cannot be seen. More often, considerable detail of the 
 vessels of the choroid will be visible. This occurs under two 
 conditions: In some cases there is no obscuration by the 
 pigment layer of the retina, and the choroidal pigment is very 
 abundant and collected into the intervascular spaces; then 
 these stand out as dark islands separating bright-red lines and 
 bands, which anastomose freely, the choroidal vessels (Fig. 
 44, Plate IV). In other instances, there is very little pig- 
 mentation in either retina or choroid, allowing the choroidal 
 vessels to be seen plainly, now presenting the picture of 
 bright-red anastomosing channels with brighter interspaces 
 (Fig. 42, Plate III). The choroidal vessels are most mark- 
 edly visible in the periphery, and are readily distinguished 
 from retinal vessels by being less sharply defined, flat, having 
 no light-streak, by their free anastomosis, and by the 
 
36 OBJECTIVE EXAMINATION OF THE EYE 
 
 fact that they obviously lie in a plane posterior to the 
 retina. 
 
 The Region of the Macula Lutea (Fig. 47, Plate V), physio- 
 logically the most important part of the fundus, is situated 
 rather less than two disc-diameters to the temporal side of the 
 entrance of the optic nerve, in the line of direct vision. Very 
 often this region presents scarcely any distinctive feature. 
 It is always devoid of visible vessels, and is somewhat darker 
 than the rest of the fundus. Frequently a bright spot is seen 
 in its centre corresponding to the position of the fovea cen- 
 tralis, or there may be two. or three of these bright spots. 
 Sometimes the macular region is represented by a bright spot 
 surrounded by an area of dark-red color, about the size of the 
 disc, oval horizontally, and this again encircled by a bright 
 halo; this reflex is best seen in the indirect method and is 
 most marked in children of dark complexion, especially if they 
 be hyperopic. 
 
 Physiological Variations. — In children of dark complexion 
 the fundus not infrequently presents a bright lustre, which 
 changes its position with movements of the mirror, most 
 marked along the blood-vessels; it resembles the shimmer of 
 watered silk. Another peculiar but physiological appearance 
 is sometimes occasioned by opaque nerve fibres. In such cases 
 the axis cylinders of some of the optic-nerve fibres regain 
 their medullary sheath at the disc, and continue in this con- 
 dition for some distance beyond the papilla, presenting 
 whitish areas extending for a variable distance from the 
 disc and terminating in brush-like extremities (Fig. 45, 
 Plate IV). The normal fundus presents many minor varia- 
 tions; hence experience is necessary to avoid regarding these 
 as pathological. 
 
 TBANSILIiXTMINATION 
 
 This useful addition to the dark-room examination (also 
 known as Diaphanoscopy) consists of the passage of a beam 
 of light through the sclera, from behind or the side forward, 
 
PLATE V 
 
 Fig. 46. — Physiological Excavation of the Disc 
 (Direct Method of Ophthalmoscopy). 
 
 Fig. 47.— The Region of the Macula Lutea 
 (Direct Method of Ophthalmoscopy). 
 
TRANSILLUMINATION 37 
 
 causing a reddish glow in the pupil; anything which intercepts 
 the light, such as a solid mass, will cause a more or less dense 
 shadow. The Wiirdemann model is one of the best; resem- 
 bling a fountain pen in shape and size, one end for battery 
 cords, the other, provided with a lens-capped lamp and glass 
 
 \ 
 
 Fig. 48. — The WUrdemann Transilluminator. 
 
 rod, is pressed upon the sclera, after local ansesthesia. Orig- 
 inally devised for intraocular exploration, especially in the 
 differential diagnosis of simple retinal detachment from that 
 due to a growth, its use has been extended; it is valuable and 
 supplements oblique illumination, the light being now thrown 
 directly upon the cornea, in examination of the anterior por- 
 tion of the eyeball. 
 
 The May Electric Ophthalmoscope serves as an excellent 
 transilluminator: The circular disc supporting the series 
 of convex and concave lenses is removed, together with the 
 lens-capped cylinder covering the lamp; a piece of three- 
 sixteenths-of-an-inch soft rubber tubing, one-half-inch in 
 length, is slipped over the lamp; the end of the tubing is 
 applied to the external surface of the eyelids and pressed 
 against the eyeball; no anaesthesia of the sclera is necessary 
 and the examination is devoid of any discomfort to the 
 patient. 
 
CHAPTER IV 
 
 AFFECTIONS OF THE EYELIDS 
 
 Anatomy and Physiology. — The eyelids (palpebrae) consist of 
 
 movable folds formed, from before backward, of skin, loose connective 
 
 tissue, muscular tissue, tarsus and fascia, and conjunctiva (Fig. 49). 
 
 In addition, they present eyelashes, numerous 
 
 glands, blood-vessels, lymphatics, and nerves. 
 
 The integumevi is thin and delicate, and 
 joined to the subjacent muscles by loose are- 
 olar tissue, free from fat. These characteristics 
 explain the readiness with which extravasations 
 of blood and cedematous sweUings occur in this 
 region. 
 
 The margin of each hd presents in front a 
 rounded anterior lip from which the eyelashes 
 (cilia) spring; these form two or t^hree rows of 
 short, thick, curved hairs, their roots deeply 
 embedded in the connective tissue and muscle; 
 they are provided with sebaceous follicles, 
 known here as Zeiss's glands. In this situation 
 are also found modified sweat-glands, known as 
 the glands of Moll, which open into the hair- 
 follicles of the ciha. Behind, the lid margin 
 presents a sharp posterior Up; directly in front of 
 this are the openings of the Meibomian glands. 
 The surface between these two lips is known 
 as the intermarginal space. The margins of 
 the lids unite at an acute angle externally 
 (external canthus). At the internal canthus the junction presents a 
 rounded space which is occupied by a small, reddish elevation of modi- 
 fied skin, the caruncle. 
 
 In and behind the subcutaneous connective tissue we find the mus- 
 cles of the eyehds. The levator palpehra superioris is attached to the 
 upper border and anterior surface of the tarsus and to the skin of the 
 middle of the upper lid. The orbicularis muscle lies between tarsus and 
 integument, being attached to the latter, but gUding loosely over the 
 former; it forms a flat circle which surrounds the palpebral aperture; 
 its function is to close the Uds. We also find a layer of unstriped 
 
 38 
 
 Fig. 49. — ^Longitudinal 
 Section of the Upper 
 Lid. S, Skin; 0, or- 
 bicularis muscle; C, 
 conjunctiva; T, tar- 
 sus; Mf opening of 
 Meibomian gland; L, 
 lashes. 
 
BLEPHARITIS 39 
 
 muscular tissue inserted into the upper border of the tarsus and known 
 as Mueller's muscle. 
 
 The tarsus consists of a thin plate of dense fibrous tissue, giving to 
 each Ud its firmness; it is larger in the upper than in the lower Ud. 
 The tarsi are connected with the lateral walls of the orbit by means of 
 the internal and external tarsal ligaments, and to the upper and lower 
 margins by an aponeurotic layer of fibrous tissue known as the palpe- 
 bral fascia or ligament. In the substance of the tarsus, occurring in 
 parallel rows, are found the Meibomian glands, thirty to forty in the 
 upper and twenty to thirty in the lower lid. These are elongated seba- 
 ceous glands with blind extremities and numerous csecal appendages, 
 filled with fatty secretion, and opening on the free margin of the lid. 
 
 The palpebral conjunctiva is thin, vascular, and closely adherent to 
 the tarsus. 
 
 The arteries are derived principally from the ophthalmic. The veins 
 empty into the ophthalmic, temporal, and facial. The lymphatics pass 
 to the pre-auricular, submaxillary, and parotid lymphatic glands. The 
 third nerve supplies the levator, the facial the orbicularis, and the sym- 
 pathetic the unstriped muscular tissue (Mueller's muscle). The sen- 
 sory nerve supply is derived from the fifth. 
 
 The Uds protect the eyes from external injury, foreign bodies, undue 
 exposiire, and excessive Hght. They serve to distribute the tears and 
 the secretions from the various glands, thus lubricating the eyeball, 
 keeping the surface of the cornea moist and transparent, and washing 
 away any dust which may have found its way into the eye. 
 
 The Common Affections of the Eyelids are blepharitis, hor- 
 deolum, chalazion, trichiasis, entropion, ectropion, ptosis, 
 tumors, and injuries. 
 
 BLEPHARITIS 
 
 Blepharitis Ciliaris is a very common, chronic inflammation 
 of the margin of the lids, often associated with the formation 
 of scales and crusts (Fig. 53, Plate VI). It occurs under two 
 forms: (1) non-ulcerative, (2) ulcerative. 
 
 Symptoms. — In the non-ulcerative form (squamous blepha- 
 ritis), the margins of the lids are swollen and reddened, and 
 present numerous whitish scales at the bases of the lashes; 
 the latter fall out readily, but are replaced, since there is no 
 destruction of the hair-follicles. In this variety may be 
 included cases of simple hypercemia of the lid margin in which 
 
40 AFFECTIONS OF THE EYELIDS 
 
 there are no scales but the border of the lid is reddened and 
 swollen; this condition is frequently seen in persons having a 
 combination of fair complexion, delicate skin, and light- 
 colored hair. 
 
 In the ulcerative form, the edges of the lids are reddened 
 and swollen, and present yellowish crusts which glue the 
 lashes together. On removing these crusts small ulcers are 
 seen about the attachments of the lashes; these ulcers bleed 
 readily. The lashes become distorted, fall out, and grow 
 scarce, since they are not replaced on account of destruction 
 of the hair-follicles. 
 
 In both forms there will be more or less disfigurement, the 
 lids may be stuck together in the morning, and the patients 
 complain of itching, soreness, epiphora, sensitiveness to light, 
 and ocular fatigue during work, especially with artificial 
 illumination. 
 
 Complications and Sequelae occur especially in the ulcera- 
 tive form. There may be conjunctivitis, styes, permanent 
 loss of a greater or lesser number of lashes, hypertrophy of the 
 lid margin, trichiasis, and ectropion. 
 
 Etiology. — Poor hygienic surroundings; debilitated con- 
 ditions of the system; following exanthemata, especially 
 measles; exposure to irritating atmosphere — smoke, wind, 
 dust; late hours; insufficient sleep; uncorrected errors of 
 refraction, especially hyperopia and astigmatism; chronic 
 conjunctivitis; lacrymal disorders; nasal affections; lack of 
 cleanliness. The disease occurs at all ages, but is very com- 
 mon in children. 
 
 Treatment. — The disease is apt to be obstinate. Removal 
 of the cause, if possible, is of the greatest importance. Local 
 cleanliness, change of faulty habits, and correction of errors 
 of refraction are great aids to treatment. The edges of the 
 lids must be cleansed thoroughly with soap and water, or 
 water to which a little borax, bicarbonate of sodium, or 
 hydrogen peroxide has been added (applied upon absorbent 
 cotton), using enough friction to remove all scales and crusts, 
 
BLEPHARITIS 41 
 
 dried, and then massaged with a 2-per-cent. ointment of the 
 yellow oxide of mercury, ammoniated mercury, or ichthyol. 
 In the ulcerative form an occasional application of 2-per-cent. 
 solution of silver nitrate to the raw spots will prove useful. 
 In severe and long-standing cases it will be necessary to pull 
 out all the lashes, and then to apply the treatment given 
 above. 
 
 Tarsitls is an infrequent form of chronic inflammation, usually 
 syphilitic (tertiary, gummatous infiltration of the tarsus), though it 
 may be tuberculous or trachomatous, in which the lid is much thickened 
 and its skin tense and reddened. 
 
 Phthiriasis Palpebranun is an uncommon affection, usually found 
 in children, in which the lashes are covered with the black nits of the 
 crab louse (pediculua pubis). There are redness and itching of the 
 border of the Uds. The parasites are quickly destroyed with blue 
 ointment. 
 
 Syphilis of the Lids is occasionally seen as a primary sore, in the 
 secondary stage, or in the form of gumma. Chancre having the same 
 characteristics as when found elsewhere occurs upon the Ud margin, 
 usually near the inner canthus, accompanied by enlargement of the pre- 
 auricular and submaxillary lymph glands; it might be mistaken for stye, 
 suppurating chalazion, dacryocystitis, vaccinia, or rodent ulcer. 
 
 Vaccinia of the Lids is now and then met with as the result of the 
 careless inoculation with the secretion from vaccine pustule elsewhere. 
 It presents an ulcer covered with grayish exudate or crust, situated at 
 the margin of the lid, usually the lower, sometimes upon both; it is 
 accompanied by marked swelling and redness of the Uds and by enlarge- 
 ment of the pre-auricular and submaxillary lymph glands. 
 
 (Edema of the Lids is a very common symptom, being 
 favored by the structure of these parts. It may be (l) in- 
 flammatory, accompanying affections of the lids and adjacent 
 parts, such as styes, dacryocystitis and affections of the nasal 
 accessory sinuses, or existing as a symptom of violent inflam- 
 mations of the interior of the eye, such as iridocyclitis, acute 
 glaucoma, panophthalmitis, iand orbital cellulitis; (2) trau- 
 matic when due to injuries, including the sting of insects; 
 (3) systemic, in renal and cardiac disease; and (4) non- 
 
42 
 
 AFFECTIONS OF THE EYELIDS 
 
 inflammatory, of which a rather frequent type is angioneurotic 
 oedema, a recurrent variety which comes on rapidly, is often 
 marked enough to close the lids, is unaccompanied by any 
 change in the eyes, causes much alarm to the patient, and 
 disappears about as quickly as it came on; this form is most 
 frequently seen in women, especially at the menstrual period; 
 it is allied to urticaria and is most promptly relieved by a 
 brisk saline cathartic and large doses of sodium bicarbonate. 
 Herpes Zoster Ophthalmicus is characterized by a unilat- 
 eral, herpetic eruption following the distribution of the oph- 
 thalmic division of the fifth 
 nerve. The affection begins 
 with severe neuralgic pain of 
 one side of the head and face, 
 and constitutional disturbance. 
 The eruption presents vesicles 
 situated upon inflamed bases; 
 the vesicles are at first filled 
 with clear fluid, but this soon 
 becomes cloud.y; subsequently 
 discolored crusts form and 
 dropoff, leaving permanent and 
 disfiguring scars. In some 
 cases, especially when the na- 
 sal branch is included, the eye- 
 ball becomes implicated; then 
 the cornea presents one or 
 more vesicles changing to ulcers, and the iris and ciliarj^ 
 body may become involved, leading to a very serious ocular 
 condition. 
 
 The affection is due to disease of the Gasserian ganglion 
 or the trunk of the trigeminus. It is most frequently 
 observed in elderly patients of feeble constitution. Its dura- 
 tion is from three weeks to several months. The prognosis is 
 usually good, but is serious when the cornea and deeper parts 
 of the eye are involved. 
 
 Fig. 50. — Herpea Zoster Ophthalmicus. 
 
HORDEOLUM OR STYE 43 
 
 Treatment. — ^At first cooling lotions; after vesicles have 
 appeared, bland dusting powders (talcum, rice starch, zinc 
 oxide) or 10-per-cent. ichthyol ointment; the galvanic current 
 may be of service. Internally, quinine, iron, arsenic, and the 
 salicylates are most useful. Severe pain may call for morphine. 
 
 hordeolum: ob. stye 
 
 A circumscribed, acute inflammation of the margin of the 
 lid, originating from staphylococcus infection of one of the 
 sebacious follicles of the lashes (Zeiss's glands), usually ending 
 in suppuration. Styes are sometimes divided into (a) exter- 
 nal, the common form here described, and (b) internal, an 
 infrequent variety generally known as " suppurating cha- 
 lazion" (p. 44). 
 
 Symptoms. — A red swelling (Fig. 51, Plate VI) appears at 
 the margin of the lid, accompanied by pain, tenderness, and 
 often by considerable oedema. Very soon a yellowish point 
 will be seen, indicating suppuration. 
 
 Etiology. — Styes occur at all ages. They are very common 
 in young adults. They often appear in crops. They are fre- 
 quently associated with a deranged condition of the system, 
 constipation, and uncorrected errors of refraction. 
 
 Treatment. — It is sometimes possible to abort a stye by the 
 use of cold compresses. As a rule, however, this is unsuc- 
 cessful. Hot compresses are then indicated to hasten sup- 
 puration. As soon as a yellow spot is seen, the pus should 
 be evacuated either by pulling out a lash or by a horizontal 
 incision, and then squeezed out. To prevent the formation 
 of others, the general health should be looked after, constipa- 
 tion relieved, and errors of refraction corrected. When per- 
 sistently recurring, calcium sulphide, hypophosphites, and 
 general tonics are indicated; in very obstinate cases, the use 
 of autogenous vaccine is of value. The tendency to recur 
 is often checked by treatment of the blepharitis which is 
 frequently present. 
 
44 AFFECTIONS OF THE EYELIDS 
 
 CHALAZION 
 
 Chalazion (tarsal tumor, tarsal qjst, Meibomian cyst) is a 
 chronic inflammatory enlargement of one of the Meibomian 
 glands in consequence of stoppage of its duct, accompanied 
 by involvement of the surrounding tissues. It occurs most 
 frequently in adults. Very often several are found at the 
 same time, and there is some tendency to recurrence in crops. 
 The contents consist of small, round cells with some giant 
 cells (non-tuberculous) ; the centre undergoes mucoid degen- 
 eration; there is a fibrous envelope, but no true cyst wall. 
 
 Symptoms. — The process develops slowly with insignificant 
 or no symptoms until, after weeks or months, it has reached 
 the size of a small or large pea. Then it presents a noticeable 
 swelling (Fig. 52, Plate VI), which feels hard, and is adherent 
 to the tarsus, but not to the skin. On everting the lid its 
 situation is shown by a red or purple (later gray) discolora- 
 tion of the conjunctiva and sometimes by a small mass of 
 granulation tissue. Sometimes chalazia disappear spontane- 
 ously. Occasionally they suppurate (internal stye, suppurat- 
 ing chalazion), this change being accompanied by acute 
 inflammatory symptoms. Chalazia may be annoying merely 
 on account of the disfigurement, or on account of the con- 
 junctival irritation which they occasion. 
 
 Treatment. — When small, they need not be interfered with; 
 occasionally we can cause their disappearance by the frequent 
 application of ointments of the yellow oxide of mercury or 
 ammoniated mercury, associated with massage and hot com- 
 presses. When larger, we remove them by operation, usually 
 through the conjunctiva: The eye is anaesthetized with 
 holocain or cocaine, the lid everted, the affected spot ren- 
 dered prominent, and a vertical incision made through con- 
 junctiva and wall of the chalazion with a Beer's knife (Fig. 
 58); the contents (Meibomian secretion, granulation tissue, 
 and mucilaginous fluid) are removed and the walk thor- 
 oughly scraped with the chalazion curette (Fig. 59). If two 
 
Fir;. r»l.- — Ilordeulimi. 
 
 Fi(j, 51^. — C'lialaziort. 
 
 Fig. 5;^. — -Blepharitis. 
 
 Fi(j. 54.— Ectropion. 
 
 Fig. 5.').— (Minmic Dacryocyslilis with 
 Distention of tlie J^ac-rymal Sac. 
 
 Fig. 56.— Acute Dae 
 
 i\\'oc>-.stitis. 
 
CHALAZION 
 
 45 
 
 or three drops of a 2-per-cent. solution of novocain in 1 : 3000 
 adrenalin are injected into or around the cyst, the operation 
 will be painless and bloodless. 
 
 When the chalazion is more accessible externally, it may 
 be advisable to operate through the skin by means of a hori- 
 zontal incision; the tumor may be 
 excised or merely incised and cu- 
 retted; one or two sutures are then 
 employed. In such cases, the lid 
 clamp (Fig. 60) or the chalazion 
 forceps (Fig. 61) is applied with 
 
 Pig. 57. — Small Pig. 58. — Pig. 59. — Cha- Fig. 60. — Desmarre's Pig. 61.— 
 Scalpel. Beer's Knife, lazion Curette. Lid Clamp. Chalazion 
 
 Forceps. 
 
 the ring blade surrounding the tumor on the cutaneous 
 surface and tightened so as to furnish a bloodless field. 
 Here also it is well to inject two drops of a 2-per-cent. solu- 
 tion of novocain in 1 : 3000 adrenalin previous to the incision. 
 
 Following the operation the cavity will be filled with a 
 blood clot; this causes a continuation of the disfigurement for 
 several days; absorption may be hastened by gentle massage 
 for a few minutes several times a day. 
 
 Since chalazia occur rather more frequently in ametropia 
 individuals than in others, correction of errors of refraction 
 will tend to prevent recurrences. 
 
46 
 
 AFFECTIONS OF THE EYELIDS 
 
 TRICHIASIS 
 
 Trichiasis is an inversion of a varying number of lashes, so 
 that they rub against the cornea (Figs. 63 and 68). 
 
 Distichiasis is an infrequent condition, usually congenital, 
 in which the lashes can be separated into two rows, the pos- 
 
 III 
 
 Fig. 62. Fig. 63. Fig. 64. Fig. 65. Fig. 66. 
 
 Figs. 62-66. — Diagrammatic Section of the Upper Lid, showing Normal and Abnormal 
 Position of Tarsus and Lashes. Fig. 62, Normal lid; Fig. 63, trichiasis; Fig. 64, 
 distichiasis; Fig. 65, entropion; Fig. 66, ectropion. 
 
 terior of which is directed backward so as to rub against the 
 eyeball (Fig. 64). 
 
 In both of these conditions the margins of the lids have a 
 normal position, the displacement affecting the lashes only. 
 
 Symptoms. — The misdirected lashes cause mechanical 
 irritation and injury to the cornea, with congestion, pain, 
 lacrymation, photophobia, opacities, vascularization, and 
 ulceration. 
 
 Etiology. — ^The most frequent cause is cicatricial contraction 
 of the conjunctiva and tarsus in old cases of trachoma. Other 
 
 causes are blepharitis, 
 burns, injuries to the 
 lids, and operations 
 upon the lids. 
 
 Treatment . — 1 . 
 
 Epilation.—When the 
 
 misdirected lashes are few in number, we may epilate with 
 
 the cilia forceps (Fig. 67), repeating this every few weeks, 
 
 since the lashes grow again. The misdirected lashes are 
 
 Fig. 67. — Cilia Forceps. 
 
ENTROPION 
 
 47 
 
 sometimes normal but often very fine, short, and of a pale 
 color, and therefore not easily detected. 
 
 2. Electrolysis. — A sponge electrode corresponding to the 
 positive pole is applied to the temple, and a fine platinum 
 needle forming the negative pole is introduced into the hair- 
 follicle, destroying the latter; a very weak galvanic current (2 
 milliamperes) is employed. This method results in a perma- 
 nent cure, but is quite painful; cocaine should be injected 
 into the lid margin. 
 
 3. Operation. — When a great number or all of the lashes 
 are misdirected, operations must be performed. These have 
 for their object correction of the faulty -position or transplan- 
 tation of the lashes. Since trichiasis is frecjuently associated 
 with entropion, these operations will be considered in connec- 
 tion with the latter disease. 
 
 ENTROPION 
 
 A rolling in of the margin of the lid (and with it the lashes) 
 (Figs. 65 and 68). 
 
 Varieties. — There are two forms: (1) Cicatricial, due to 
 cicatricial changes in the 
 conjunctiva and tarsus, most 
 commonly affecting the up- 
 per lid. (2) Spas7nodic, due to 
 spasm of the palpebral por- 
 tion of the orbicularis mus- 
 cle, almost always occurring 
 in the lower lid. The second 
 variety is generally found 
 in old persons (senile entro- 
 pion) who are predisposed 
 through relaxation of the 
 palpebral skin and the deep 
 
 position of the eyeball resulting from the absence of 
 fat. 
 
 Symptoms. — Those due to mechanical irritation and injury 
 
 
 ||J, 
 
 ' '^^SHIP^ 
 
 ^^1 
 
 
 68. — Entropion of the Lower Lid. 
 Trichiasis of the Upper Lid. 
 
48 
 
 AFFECTIONS OF THE EYELIDS 
 
 to the cornea: congestion, pain, lacrymation, photophobia, 
 opacities, vascularization and ulceration of the cornea. 
 
 Etiology. — Cicatricial form: principal cause, the cicatricial 
 changes in old cases of trachoma, also burns and other in- 
 juries to the lids, and operations upon the lids. Spasmodic 
 form: atrophy or absence of eyeball, blepharospasm, inflam- 
 matory conditions of the lids and conjunctiva, and the pro- 
 longed wearing of a bandage (in senile patients). 
 
 Treatment. — Non-operative treatment may be of service in 
 the spasmodic variety. If a bandage causes the entropion, we 
 must either leave this off or apply a small roll of lint to the 
 orbital margin beneath the bandage, exerting pressure in such 
 a manner as to neutralize the inversion. In other cases we 
 try to remove the cause. The lid may be kept everted for a 
 few days by collodion painted on the external surface, or by 
 adhesive plaster passing from the margin of the lid to the 
 cheek. If these simple means do not answer, an operation 
 is indicated. In the cicatricial form, operation is always 
 necessary. 
 
 Operations for Trichiasis and Entropion. — The 
 choice of an operation (there are a great many) is influenced 
 
 Fig. 70. — Knapp's Lid Clamp 
 
 by the peculiarities existing in the individual case. The object 
 of these operations is to remove the displaced lashes from con- 
 
ENTROPION 49 
 
 tact with the eyeball either (1) by changing the direction of 
 the lashes from a faulty to a correct one, (2) by transplanting 
 the offending zone, or (3) by straightening the curved tarsus. 
 
 In these operations we use either a horn or metal plate 
 (Fig. 69), or the lid clamp (Fig. 70), to protect the eyeball, 
 check hemorrhage, and give proper support to the lid. The 
 horn or metal plate is passed beneath the lid and pressed for- 
 ward. If the lid clamp be used, its solid blade is passed 
 beneath the lid, and the latter secured by tightening the 
 screw of the instrument. Though the injection of 2-per-cent. 
 solution of novocain in 1 : 3000 adrenalin may be used in the 
 simple procedures of this sort, in most lid operations general 
 ana-sthesia is required. 
 
 The Jaesche-Arlt Operation attaches the zone of hair-fol- 
 licles at a higher level by shortening the skin of the lid. The 
 lid is split through its entire length in the intermarginal 
 
 Fig. 71. — The Jaesche-Arlt Operation for En FiG. 72.— The Jaesche-Arlt 
 
 tropion. Incisions. Operation for Entropion. 
 
 Completed. 
 
 space, SO that the anterior lip contains the hair-follicles. A 
 second incision, dividing the skin down to the tarsus, is made 
 4 mm. from and parallel to the margin of the lid. A third 
 incision extends upward in a curve between the two ends of 
 the second incision. The elliptical piece of skin bounded by 
 the second and third incisions is dissected away (Fig. 71) 
 
50 
 
 AFFECTIONS OF THE EYELIDS 
 
 without injury to the orbicularis and the margins of the 
 defect arc united by fine silk sutures (Fig. 72). In this 
 manner the strip of integument containing the cilia is drawn 
 upward and the lashes are tilted forward, away from the 
 cornea. The area from which the skin and lashes have been 
 displaced may be allowed to cicatrize, or may be covered by 
 the excised strip of integument properly trimmed, which will 
 attach itself in a few days. 
 
 Hotz's Operation raises the zone of hair-follicles bj^ attach- 
 ing the skin to the upper border of the tarsus. A curved inci- 
 sion is made through the skin of the lid following the upper 
 
 Fig. 73.- 
 
 -The Hotz Operation for 
 Entropion. 
 
 Fig. 74.— The Hotz Opera- 
 tion for Entropion (Shown 
 
 border of the tarsus, from 2 mm. above one canthus to a 
 corresponding distance above the other. While the edges of 
 the wound are separated, a narrow strip of orbicularis along 
 the upper border of the tarsus is exsected. The sutures, 
 three or more in number, are then passed through the lower 
 wound margin, upper border of tarsus, returning through the 
 orbito-tarsal fascia, and finally through the upper wound mar- 
 gin (Figs. 73 and 74). This operation may be modified by 
 
OPERATIONS F(Jll ENTKOl'ION 
 
 51 
 
 the addition of an intcrmarginal incision, by grooving tlio 
 tarsus, and by excising a liorizontal strip of integument. 
 
 The Streatf eild-Snellen Operation aims at straightening the 
 inverted lid by the removal of a wedge-shaped ■piece fi'om the 
 
 Fig. 75. — The Streatfeild-Siiellen Operation for Entro- 
 pion. One of the Threads has been Tied. 
 
 Fig. 7C.— The Streat- 
 feild-Snellen Opera- 
 tion for Entropion 
 (Shown in Section). 
 
 tarsus. A transverse incision is made through the slvin, 2 
 mm. above and parallel to the margin of the lid along its 
 entire length. A strip of orbic- 
 ularis is excised, thus exposing 
 the tarsus. A wedge-shaped 
 piece, the apex of which is 
 directed toward the conjunctiva, 
 is removed from the tarsus along 
 its entire length. The cut sur- 
 faces of the tarsus are brought 
 into contact by three sutures, 
 provided with needles at both 
 ends, in the following manner: 
 One needle is passed through 
 the tarsus above the groove; 
 
 both needles are then carried down in front of the wound 
 in the tarsus, and then between tarsus and skin, and brought 
 
 Fig. 77.— Gaillard- Fig. 78.— Gaillaid- 
 Arlt Sutures for Arlt Sutures for 
 Entropion. Entropion. 
 Threads in Place. Threads Tied. 
 
52 
 
 AFFECTIONS OF THE EYELIDS 
 
 out just above the free margin of the lid (Fig. 76) alsout 4 
 mm. apart. The two threads arc tied upon a bead (Fig. 
 75) and then turned up over the forehead and secured by 
 plaster. The cutaneous wound closes of itself. More 
 lironounccd eversion is produced if the threads are passed 
 behind the cilia, emerging just above the posterior lip of 
 the lid margin. 
 
 Operations for Spastic (Senile) Entropion include (1) ex- 
 cision of a horizontal strip of skin with the underlying orbi- 
 cularis, the width being gauged so that when pinched up it 
 
 shall cause the disappear- 
 ance of entropion without 
 producing ectropion; the 
 margins of the wound are 
 then united by silk sut- 
 ures; (2) siihcutaneous sut- 
 ures (Gaillard-Arlt) , which 
 enter through the skin 
 near the lid-margin and 
 emerge three-quarters of 
 an inch below (Fig. 77); 
 parallel threads are used, 
 forming a loop near the 
 border of the lid; the 
 threads are tightened over 
 a small roll of plaster 
 (Fig. 78); they are allowed to remain in place for a week; 
 in this manner cicatricial bands are formed; (3) Hotz's op- 
 eration; and (4) canthoplasty. 
 
 Canthoplasty consists in an enlargement of the palpebral fis- 
 sure l5y division of the external canthus. The lids being 
 separated and stretched at the external canthus with the 
 fingers, one blade of blunt-pointed, straight scissors is intro- 
 duced behind the external commissure as far as possible, and 
 the entire thickness divided, the wound in the skin being 
 made a little longer than that in the conjunctiva. This leaves 
 
 Fig. 79. — Canthoplasty. 
 
ECTROPION 53 
 
 a rhomboidal wound. The conjunctiva at the apex of the 
 wound is loosened from underlying tissue and stitched to the 
 centre of the incision in the skin. A second suture is passed 
 through the upper, and a third through the lower part of the 
 wound, uniting conjunctiva to skin (Fig. 79). 
 
 The sutures are inserted so as to prevent reunion, thus 
 making the effect permanent. If a temporary enlargement is 
 desired, we omit the sutures; the operation is then known as 
 canthotomy or temporary canthoplasty. 
 
 The indications for canthoplasty are blepharospasm, spas- 
 tic entropion, and certain cases of trachomatous parmus. 
 Temporary canthoplasty is indicated in acute purulent con- 
 junctivitis, phlyctenular keratitis and other affections, when 
 swelling of the lids exerts injurious pressure upon the eyeball, 
 in blepharospasm, and in the removal of an enlarged eyeball 
 or an orbital tumor, 
 
 ECTROPION 
 
 An eversion of the lid with exposure of more or less conjunc- 
 tival surface (Fig. 54, Plate VI, and Fig. 66). It may affect 
 the upper or the lower lid, or both. 
 
 Sjrmptoms. — Epiphora (from eversion of punctum) causing 
 excoriations and eczema of the lower lid, which, in turn, 
 through contraction, increase the deformity. The exposed 
 conjunctiva becomes reddened and hypertrophied. In 
 marked cases the cornea may suffer, as a result of imperfect 
 closure of the lids. 
 
 Etiology. — (1) Cicatricial contraction from wounds, oper- 
 ations, burns, ulcers, and caries of the orbital margin or 
 surrounding surfaces (cicatricial ectropion). (2) Chronic 
 conjunctivitis and blepharitis associated with considerable 
 hypertrophy (mechanical ectropion). (3) Relaxation of the 
 skin and orbicularis in old people (senile ectropion), affecting 
 only the lower lid. (4) Affections of the facial nerve, causing 
 paralysis of the orbicularis (paralytic ectropion), affecting only 
 the lower Ud. (5) Spasmodic contraction of the marginal 
 
54 AFFECTIONS OF THE EYELIDS 
 
 portion of the orbicularis (spasmodic ectropion), seen especially 
 in children with acute forms of conjunctivitis associated with 
 considerable blepharospasm. 
 
 Treatment. — Non-operative: The spasmodic form is fre- 
 quently relieved by a suitable retaining bandage applied after 
 the lid has been properly placed. In the paralytic form we 
 employ a bandage, at the same time attempting to cure the 
 facial paralysis. In the senile form we put on a bandage at 
 night, and slit open the lower canaliculus; we instruct the 
 patient, when wiping away the tears, to press upward and 
 inward and not downward and outward. In slight cases of 
 ectropion associated with much conjunctival hypertrophy, 
 painting the exposed surface with 2-per-cent. solution of 
 silver nitrate may be of service. Thorough and persistent 
 massage of a cicatrix or of the thickened lid margin of ble- 
 pharitis may give some relief. When these simple procedures 
 do not answer, and especially in cicatricial ectropion, we 
 must resort to operative intervention. 
 
 Operations for Ectropion. — In senile and paralytic 
 forms of ectropion the lid may be replaced by (1) Snellen's 
 sutures; (2) by reduction of 
 the length of the lid-border; 
 and (3) by tarsorrhaphy. 
 
 Snellen's Sutures. — Two 
 loops of thread are placed at 
 the junction of the middle 
 with the outer and inner third 
 of the lid respectively, enter- 
 ing the everted conjunctiva at 
 
 its most prominent part (Fig. Fig. so. — Snellen's fig. si. — SneUen'a 
 
 80), brought out on the face 2 futures tor Ectro- sutures for Eetro- 
 
 , , . . P'™- Threads in pion. Threads 
 
 cm. below and tied over a Position. Tied. 
 
 piece of rubber tubing, so as 
 
 to produce a slight amount of entropion (Fig. 81); the 
 threads are tightened from day to day until they have 
 nearly cut through, when they are removed. 
 
OPERATIONS FOR ECTROPION 55 
 
 Shortening the Margin of the Lid (Adam's Operation) is 
 applicable when there is considerable elongation. A wedge- 
 shaped piece is excised from the whole thickness of the lid 
 (Fig. 82), the base corresponding to the margin of the lid and 
 varying from 5 to 10 mm. in width, according to the amount 
 of shortening required; the edges are brought together by a 
 harelip pin and the cutaneous margins by silk sutures (Fig. 
 83). The piece may be excised from the centre of the lid; 
 but, to prevent notching, it is better to operate at the external 
 canthus. 
 
 For cicatricial ectropion a great many operative procedures 
 have been advocated. An essential condition for success is 
 the thorough division of all cicatricial adhesions, so that the 
 lid assumes a natural position, the object of any operation 
 being to prevent recicatrization. If the ectropion is slight 
 and but little skin has been lost, it may be sufhcient to divide 
 the cicatricial bands subcutaneously, or to cut out the scar 
 
 Pig. 82.— Adam's Operation for Ectro- Fig. 83.— Adam's Operation for Ectropion, 
 pion. Incisions. Completed. 
 
 portion and bring the margins of the wound together by 
 sutures. A procedure very frequently used is 
 
 The V Y Operation {Wharton Jones). — A V-shaped incision 
 is made with the apex directed away from the palpebral mar- 
 gin, the incision including the cicatrix (Fig. 84). The skin 
 is freed from underlying parts, not only in the V-shaped area, 
 
56 
 
 AFFECTIONS OF THE EYELIDS 
 
 but also to either side. The V-shaped area is slid upward 
 until slight inversion of the lid margin is produced. The 
 
 Fig. 84. — The V Y Operation for Ectro- 
 pion. The Incisions have been made 
 and the Sutures are in Position. 
 
 Fig. 85.- 
 
 -The V Y Operation for Ectro- 
 pion. Completed. 
 
 margins of the incisions are then brought together by sutures 
 in such a manner that the figure Y results (Fig. 85). 
 
 In more extensive cicatricial ectropion aplastic operation is 
 usually recjuired (blepharoplasty) . 
 
 Blepharoplasty consists in covering the defect formed by the 
 excision of a cicatrix, new growth, or extensive ulceration, 
 with skin-flaps with a pedicle, taken from some adjacent part, 
 or by means of skin-grafts. In such operations it is cus- 
 tomary to close the lids temporarily by several sutures so as 
 to prevent the contraction of the cicatricial tissue from un- 
 doing the result accomplished bj' the operation. Of the 
 many blepharoplastic operations with pedunculate skin- 
 flaps, Knapp's, Dieffenbach's, and Fricke's methods are the 
 ones most commonly employed. 
 
 Knapp's Method (lower lid) consists in detaching a lateral flap on 
 each side of the defect in the Ud, freeing it from adjacent tissue, draw- 
 ing the two flaps over the defect, and uniting them by a vertical row of 
 sutures. 
 
 Diejfeiihach's Method (lower lid) makes use of an adjacent quad- 
 rangular flap taken from the cheek and slid inward so as to cover the 
 defect of the lid. 
 
OPERATIONS FOR ECTROPION 57' 
 
 Fricke's Method (upper or lower Ud) consists in takiilg a tongue- 
 shaped flap somewhat larger than and having the shape of the defect 
 in the Ud from the temple or cheek; the base of the flap adjoins one 
 end of the hd wound, and is the part which becomes twisted when the 
 flap is transplanted into the defect. 
 
 Skin-Grafting. — The defect is filled in by one large piece of 
 skin or by a number of smaller ones, after the lid has been 
 fastened in its proper position by temporarily suturing the 
 two lids together. The grafts are taken from some part of 
 the body in which the skin is thin and delicate, such as the 
 inner side of the arm or thigh. The area of the graft," or 
 grafts, must be one-third larger than the defect to be covered, 
 to allow for shrinkage. The graft may consist of the entire 
 thickness of the skin (Wolfe's method), or comprise only the 
 epidermis (Thiersch's) . The area to be covered must be clean 
 and free from blood. When in place, the graft is covered 
 with a layer of rubber or silk protective, and then with an 
 antiseptic dressing. The dressing is not disturbed for three 
 days, and the original protective layer over the graft is often 
 left in place still longer. 
 
 Skin-grafting is now used very extensively and with very 
 good results. If a portion of the graft sloughs, the corre- 
 sponding defect can be freshened and another graft applied. 
 This method causes less disfigurement than when pedunculate 
 flaps are used. Thiersch's grafts, being thirmer and softer 
 than Wolfe's, produce better results cosmetically, and the lid 
 is not so heavy. 
 
 Tarsorrhaphy, — The object of this operation is to reduce the 
 width of the palpebral fissure by uniting the edges of the lids 
 at the outer commissure. The edges of the lids are approxi- 
 mated at the outer canthus to the required extent, so as to 
 give the operator exact knowledge as to how much union is 
 desired. A horn or metal spatula is passed behind the outer 
 commissure, and the desired length of the border of each hd is 
 excised, including the hair-follicles. The length of the flap 
 varies according to the effect desired (about 3 to 6 mm.); 
 
58 AFFECTIONS OF THE EYELIDS 
 
 its breadth is about 1 mm. To olitain firmer adhesion, the 
 border of the hd, exchiding the cilia, is denuded for 2 or 3 mm. 
 beyond the point at which the first incision stops. The 
 
 denuded edges are tlien 
 brought together by silk su- 
 tures (Fig. 86) . This opera- 
 tion is indicated in lagoph- 
 thalmos, especially in ex- 
 ■ ophthalmic goitre, in some 
 cases of senile and paralytic 
 ectropion, and in connec- 
 tion with blepharoplasty. 
 
 Fig. 86.— Tarsorrhaphy. Ankyloblepharon is the ad- 
 
 hesion of the margins of the 
 two lids; it may be partial or complete, congenital or acquired; it is 
 often associated with symblepharon. 
 
 Blepharophimosis is an apparent contraction of the palpebral fissure 
 at its outer canthus due to this angle being covered and hidden by a 
 vertical fold of skin. It is seen in lengthy cases of chronic conjunctivitis 
 in v'hich, as a result of epiphora, irritating secretions and blepharo- 
 spasm, eczema develops and draws the adjoining skin over the 
 canthus. 
 
 Symblepharon, a cicatricial attachment between the con- 
 junctiva of the lid and the eyeball, is described in Chapter 
 VII, p. 129. 
 
 PTOSIS 
 
 A drooping of the upper lid due to paralysis or deficient 
 development of the levator. All degrees of ptosis occur. 
 When marked, it interferes with vision bj^ covering the pupil. 
 Patients attempt to raise the lid by forced action of the 
 occipito-frontalis muscle, wrinkling the skin of the forehead 
 and raising the brow (Figs. 87 and 92); when the condition 
 is bilateral, they also favor exposure of the pupil by throwing 
 the head backward; these actions are characteristic accom- 
 paniments of this anomaly. Occasionally we find a curious 
 
PTOSIS 
 
 59 
 
 example of associated movement in which the patient ele- 
 vates the upper lid only while moving the jaw. 
 
 Etiology. — Ptosis may be congenital or acquired. When 
 congenital, it is usually bilateral, due to deficient develojmient 
 of the levator, and often 
 associated with other 
 congenital defects; not 
 infrequently it is heredi- 
 tary. Acquired ptosis is 
 usually unilateral; it is 
 caused by paralysis of 
 the branch of the third 
 nerve which supplies the 
 levator, and is usually as- 
 sociated with paralysis of 
 other ocular muscles sup- 
 plied by the oculo-moto- 
 rius; in rare instances, 
 when not associated in 
 this way, isolated ac- 
 quired ptosis is the result 
 of cerebral disease. 
 
 Mechanical ptosis is a 
 variety due to increased 
 
 weight of the lid (trachoma, tumors, etc.) or lack of support 
 (atrophy of globe and after enucleation) . 
 
 Treatment. — In the ordinary variety of the acquired form 
 we seek the cause of the paralysis of the third nerve (p. 368) 
 and treat this; syphilitic cases respond well to treatment; 
 electricity is used. If such treatment fails to remedy the 
 deformity after a lengthy trial, and in congenital and some 
 mechanical cases, operation is indicated. 
 
 Operations for Ptosis. — Operations for ptosis are often 
 followed by improvement, but perfect results are not the 
 rule. Their aim is (1) to produce a shortening of the upper 
 lid by excision of a strip of tarsus; (2) an elevation of the lid 
 
 Fig. 87.— Ptosis (Right Side). 
 
60 
 
 AFFECTIONS OF THE EYELIDS 
 
 by connecting it directly with the filjrcs of the occipito- 
 frontalis muscle; (3) an advcancement, resection, or both, of 
 the levator muscle; (4) to make use of the services of the 
 superior rectus. 
 
 Excision of an Elliptical Strip of Skin, often including a 
 narrow band of orbicularis (Graefe's Operation), may answer 
 in very slight examples of ptosis; but the effect produced is 
 so limited that this procedure is now rarely employed. 
 
 Excision of a Strip of Tarsus (De Grandmont's Operation). 
 — The amount of tarsus removed corresponds exactly to the 
 excess in length of the lid. The tarsal strip may be removed 
 from the external surface through an incision 4 mm. from the 
 lid margin down to the tarsus, or through the mucous surface 
 after eversion of the lid. In either case the conjunctiva cov- 
 ering the strip of tarsus is also excised. If the skin be redun- 
 dant, a sufficient amount is exsected. The tarsal wound is 
 closed with fine catgut, and the skin incision, if any, with silk. 
 The results of this operation are comparatively satisfactory. 
 
 Pagenstecher's Sutures attempt to bring the occipito- 
 frontalis to act on the lid by means of cicatricial bands. 
 
 Fig. 88.— Hess' Operation for Ptosis. In- 
 cision and Sutures. 
 
 89. — Hess' Operation for Ptosis. 
 Completed. 
 
 Three double threads of silk are passed from near the lid 
 border, where each forms a subcutaneous loop, upward imder 
 
OPERATIONS FOR PTOSLS 
 
 61 
 
 the skin, emerging above the brow and tied over rubber 
 tubing. The threads are gradually tightened until they cut 
 their way out or removed after two weeks. 
 
 Hess' Operation is a modification of Pagenstecher's. A 
 3 cm. incision through the skin of the brow permits under- 
 mining down to the lid margin. Three double sutures are 
 introduced so as to form loops about 7 mm. from the lid 
 border and passed upwards, beneath the brow, emerging 
 1 cm. above the incision, where they are tied upon small rolls 
 of gauze (Figs. 88 and 89). The skin wound is closed with 
 sutures. The doul:)le threads are allowed to remain for two 
 weeks. The skin of the lid, displaced upward, adheres and 
 gives the occipito-frontalis greater purchase; hence the 
 effects are better than when simple sutures are used. 
 
 Panas' Operation. — A horizontal incision (3 cm.) is made 
 in the ej^ebrow tlown to the periosteum, and another (2 cm.) 
 
 Fig. 90. — Panas* Operation. The In- 
 cisions have been made and the Sutures 
 are in place. 
 
 Pig. 91. — Panas' Operation. Completed. 
 
 equally deep, at the margin of the orbit; this bridge of skin 
 and muscle is undermined. A tongue-shaped flap (15 mm. 
 wide) is marked out, its surface denuded of epithelium, and 
 separated from the lid, including muscle (Fig. 90) . This flap 
 
62 AFFECTIONS OF THE EYELIDS 
 
 is drawn up under the bridge and stitched to the upper edge 
 of the upper wound by three sutures (Fig. 91). This opera- 
 tion is apt to leave somewhat conspicuous scars. 
 
 Advancement of the Levator. — The attachment of the ten- 
 don of the muscle to the tarsus is exposed and either tucked 
 on itself, or a portion exsected, producing shortening and 
 increase of power. This operation gives fair results. 
 
 Motais' Operation endeavors to assist the action of the 
 levator by exposing and freeing the middle third of the 
 superior rectus muscle and stitching this to the upper border 
 and anterior surface of the tarsus. The ptosis is often les- 
 sened, but there is risk of diplopia and depression of the 
 eyeball from weakening of the superior rectus. 
 
 Blepharospasm, a tonic or clonic spasm of the orbicularis, 
 closing the lids, is a symptom of ocular disease or of a neu- 
 rosis. The tonic form is present with foreign bodies, fissure 
 at the outer canthus, corneal affections and inflammatory 
 conditions of the eye in general; it is due to irritation of the 
 exposed terminal filaments of the trigeminus; rarely it is 
 hysterical; treatment consists in removing the cause. The 
 clonic variety often shows itself in fibrillar twitchings of a 
 portion of the muscle, especially of the lower lid, and although 
 of no importance, is annoying and often unduly alarming to 
 the patient; in such cases it may depend upon errors of 
 refraction, excessive use of the eyes, or conjunctivitis; clonic 
 spasm may also be an example of "habit chorea"; a very 
 obstinate variety is sometimes seen in elderly persons in 
 whom the marked palpebral spasms are accompanied by 
 similar movements of the neighboring facial muscles, con- 
 stituting a form of tic. 
 
 Lagophthalmos is an incomplete closure of the palpebral 
 fissure when the lids are shut, as a result of which there is 
 exposure and consequent injury to the bulbar conjunctiva 
 and the cornea. The condition may be due to congenital 
 or acquired shortening of the lids, ectropion, paralysis of the 
 
TUMORS OF THE LIDS 
 
 63 
 
 orbicularis, and protrusion or enlargement of the eyeball ; it 
 is seen also in unconscious and moribund individuals. 
 
 Epicanthus is a congenital condition, sometimes associated 
 with ptosis, usually bilateral, in which a perpendicular fold 
 of the skin extends from the 
 root of the nose to the inner 
 end of the brow, concealing 
 the inner canthus and car- 
 uncle (Fig. 92). In Mon- 
 golians it is a racial charac- 
 teristic. In slight degree it 
 is often seen in young chil- 
 dren associated with a flat- 
 tened bridge of the nose, and 
 often disappears with the 
 development of the face. 
 When sufficiently marked to 
 constitute a deformity, it 
 can be relieved by excising 
 an elliptical piece of skin 
 from the root of the nose, 
 long axis vertical, and 
 margins. 
 
 Fig. 92. — Epicanthus and Ptosis. 
 
 stitching together the free 
 
 TUMORS OF THE LIDS 
 
 Benign Tumors include xanthelasma, molluscum, ver- 
 ruca (wart), fibroma, cyst, nsvus, and milium. 
 
 Xanthelasma {Xanthoma) is a flat or slightly raised, yel- 
 lowish discoloration beneath the skin, usually multiple, found 
 most frequently near the inner canthus in elderly women; 
 it is due to fatty degeneration of connective-tissue cells wdth 
 pigment deposits. Xanthelasmata call for no interference 
 except for cosmetic reasons; they may be removed by exci- 
 sion, monochloracetic acid, or by electrolysis. 
 
 Molluscum Contagjosum is a small, white, rounded tumor, 
 about the size of a small pea, presenting a depression at its 
 
64 AFFECTIONS OF THE EYELIDS 
 
 apex; several usually occur upon the eyelids at the same 
 time; they represent a diseased condition of the sebaceous 
 glands, contain a small quantity of sebaceous material, and 
 are often considered contagious. They should be incised, the 
 contents forced out, and the base touched with the stick of 
 silver nitrate. 
 
 Militim is a small, yellowish-white elevation about the size 
 of a pin's head, due to retention in a sebaceous gland. 
 
 Small Cysts, with transparent contents, due to obstruction 
 in the outlet of sweat glands, are often seen on the lid border; 
 they give rise to irritation and should be punctured with a 
 needle or knife point. 
 
 The others resemble tumors of the same class occurring in 
 other parts of the body. Benign tumors of the lids may be 
 excised, providing no deformity results from the operation. 
 
 Malignant Tumors. — Of these, sarcoma is rare, but 
 carcinoma more common. 
 
 Carcinoma, when it attacks the lids, usually assumes that 
 form of epithelioma known as rodent ulcer. This occurs in 
 elderly persons, especially at the inner end of the lower lid 
 margin. It begins as a small pimple or wart, covered by a 
 crust, soon changes to an ulcer with indurated walls, and 
 spreads, if unchecked, to neighboring parts. Its growth is, 
 however, slow, and many years may elapse before it assimies 
 any considerable size. Treatment consists in excision; this is 
 important and always possible if done early. If advanced, 
 we may excise the lesion and cover the defect by blephar- 
 oplasty. If all the diseased tissue cannot be excised, escharot- 
 ics (chloride-of-zinc paste or chloracetic acid), the electro- 
 cautery, the x-rays, radium, or carbon dioxide snow may be 
 used. 
 
 INJURIES OF THE EYELIDS 
 
 These are quite common, and include contusions, wounds, 
 burns, and insect bites. Ecchymosis and oedema are often 
 marked symptoms on account of the looseness of the subcu- 
 taneous connective tissue. 
 
INJURIES OF THK LIDS 65 
 
 Ecchymosis (" black eye ") is usually of no importance, 
 merely causing disfigurement, which lasts one or two weeks. 
 If seen immediately, cold compresses are of service. After 
 a day or two, hot compresses and gentle message are indicated 
 to promote absorption of the extravasated blood. Occasion- 
 ally in debilitated individuals, especially if associated with 
 abrasion, abscess of the lid results, and may require horizon- 
 tal incision. In fracture of the base of the skull, blood may 
 travel along the floor of the orbit, and after a day or two 
 appear in the lower lid and bulbar conjunctiva. 
 
 Insect-bites give rise to a great deal of swelling, which is 
 best controlled by cold compresses. 
 
 Incised Wounds cause considerable gaping, if vertical, on 
 account of division of the orbicularis, and then the scar is apt 
 to be noticeable; if horizontal, the lips of the wound do not 
 tend to separate, and usually heal without deformity. In- 
 cised wounds should be cleansed and stitched at once, using fine 
 silk and delicate needles. A vertical wound of the margin 
 must be carefully sewed so that no indentation will remain- 
 Lacerated and Contused Wounds, if extensive and accom- 
 panied by much swelling, should not be closed at once. The 
 wound should be thoroughly cleansed, and after the swelling 
 has subsided the edges may be brought together. Injured 
 parts, however slenderly attached, should not be removed 
 if there is any chance of union. Care must be taken not to 
 produce deformity or shortening. It may be advisable to 
 use skin-grafts. 
 
 Bums should be irrigated with solution of boric acid, dried, 
 and covered with a bland oil or ointment; covering with 
 gauze wet with a solution of sodium bicarbonate will be 
 soothing and lessen the pain-; when granulating, skin-grafts 
 should be supplied if the defect is extensive. In powder 
 burns, the particles should be picked out with a fine needle 
 or removed with hydrogen peroxide. 
 
 Emphysema associated with injury to the lids denotes a 
 solution of continuity of the walls of the orbit, permitting 
 
66 AFFECTIONS OF THE EYELIDS 
 
 communication with the neighboring nasal or nasal accessory 
 cavities. The lids will present a soft swelling of considerable 
 size, often closing the palpebral aperture; bubbles of air, 
 becoming displaced in palpation, give rise to the sensation 
 of crepitation. A firm bandage will hasten the disappearance 
 of the air. The patient must be instructed to avoid any 
 straining efforts such as blowing the nose, which will increase 
 the emphysema. 
 
CHAPTER V 
 
 DISEASES OF THE LACRYMAL APPARATUS 
 
 Anatomy and Physiology. — The lacrymal apparatus consists of a 
 secretory portion, the lacrymal gland, and an excretory portion, which 
 collects the tears and conducts them into the inferior meatus of the nose. 
 
 The lacrymal gland is a small, oblong body, placed in the upper and 
 outer part of the orbit and divided into two portions. The upper 
 part, the larger, about the size of a small almond, is situated in a de- 
 pression in the orbital plate of the frontal bone, the lacrymal fossa, to 
 which it is fixed by connective tissue; the lower division, the smaller, 
 is known as the accessory lacrymal gland, and is 
 placed just beneath the outer part of the con- 
 junctiva of the fornix. In structure the lacry- 
 mal resembles the salivary glands, consisting of 
 acini containing cuboidal cells. The excretory 
 ducts of both portions of the gland, the lacrymal 
 ducts, six to twelve in number, pass downward 
 and empty into the external half of the supe- 
 rior fornix conjunctivae by separate orifices. 
 
 The excretory portion of the lacrymal apparatus 
 (Fig. 93) consists of the puncta, the canahculi, 
 the sac, and the duct. The puncta are two 
 minute openings, one of which is seen upon an 
 elevation on each Ud about 6 mm. from the 
 inner canthus; they are the orifices of the can- 
 aliculi. The latter extend vertically for a short 
 distance, and then, continuing at right angles, 
 pass horizontally inward in a curved course, and empty separately 
 or together into the lacrymal sac. 
 
 The lacrymal sac, situated at the inner side of the internal canthus, 
 is the upper, dilated portion of the lacrymo-nasal duct, and is placed in 
 a groove formed by the lacrymal bone and the nasal process of the 
 superior maxillary bone; it measures 12 mm. in the vertical and 6 mm. 
 in the horizontal and transverse diameters; its walls are thin; it is 
 covered in front by the internal tarsal hgament and some fibres of the 
 orbicularis muscle. 
 
 The nasal duct passes downward and slightly outward and back- 
 ward in a canal formed by the superior maxillary, lacrymal, and infe- 
 
 67 
 
 Fig. 93. — Diagram- 
 matic Illustration 
 of the Excretory 
 Portion of the Lac- 
 rymal Apparatus. 
 
68 
 
 DISEASES OF LACRYMAL APPARATUS 
 
 rior turbinated bones, and terminates below in the fore part of the infe- 
 rior meatus of the. nose; its length varies from 18 to 24 mm., and its 
 diameter from 4 to 6 mm.; it is somewhat contracted where it joins 
 the sac and again at its lower extremity. Both sac and duct are formed 
 of fibrous and elastic tissues, and mucous membrane lined with colum- 
 nar epithelium which may be ciliated; the lower part of the duct is 
 surrounded by a dense plexus of veins. 
 
 The lacrymal secretion is a sUghtly alkaline liquid containing a com- 
 paratively large amount of sodium chloride. Ordinarily the lacrymal 
 gland secretes just enough to moisten the eyeball, and this is lost by 
 evaporation. As the result of psychical stimulation or of irritation of 
 the eye or the nose, there is increased secretion. The conveyance of 
 tears from the conjunctiva to the lacrymal sac is effected by the act of 
 winking, the lubrication of the margins of the lids by fatty material 
 ordinarily preventing the tears from flowing over. 
 
 Epiphora (" watery eye "), an overflow of tears upon the 
 cheeks, is a prominent symptom in all affections of the tear- 
 conducting apparatus. It may 
 also be dependent upon increased 
 secretion (foreign bodies, inflam- 
 mations, exposure to bright light 
 and smoke, affections of the nose, 
 irritation affecting the terminal 
 twigs of the trigeminus). The 
 two forms may be combined. 
 
 Anomalies of Puncta and Can- 
 aliculi. — Normally, the lower 
 punctum is directed backward 
 and upward toward the eyeball. 
 
 Eversion of the Punctum.— 
 In this anomaly the lower punc- 
 tum looks forward and away 
 
 Fig. 95. — Punctum and Canaliculus f-„»v. +U.^ J „ • • i . i 
 
 Duator. "°°^ ^'^^ depression m which 
 
 Fig. 96.— Lacrymal Knife. the tears accumulate, and the re- 
 
 sult is epiphora. The condition 
 may be due to a relaxed state of the lids in old age and 
 in facial palsy, to conjunctivitis, blepharitis, and ectro- 
 pion. It is remedied by slitting the lower canaliculus with 
 
 Fig. 94. Fig. 95. FiG. 96. 
 
 Fig. 94.— Probe-Pointed Canaliculus 
 Knife. 
 
ANOMALIES OF PUNCTA AND CANALICULI 69 
 
 the probe-pointed canaliculus knife (Fig. 94), and keeping it 
 open by separating the edges of the incision daily for two or 
 three days. It is sufficient to open up the outer two-thirds 
 of the canaliculus. 
 
 Contraction and Obliteration of the Puncta and Canaliculi' 
 may be congenital, or acquired as a result of wounds and 
 inflammations of this region. Foreign bodies, such as an 
 eyelash or a concretion (streptothrix), may obstruct the 
 canaliculi; treatment consists in their removal with delicate 
 forceps, slitting the canaliculus if necessary. In stenosis, 
 dilatation with a canaUculus dilator (Fig. 95), or slitting the 
 canaliculus is indicated. 
 
 Diseases of the Lacrymal Apparatus may be divided into 
 those of the gland and those of the conducting portion. 
 
 The former (acute and chronic dacryoadenitis) are very 
 rare; the latter (acute and chronic dacryocystitis) are very 
 common. 
 
 CHRONIC DACRYOCYSTITIS 
 
 A chronic inflammation of the lacrymal sac usually due to an 
 obstruction in the nasal duct. It is also known as blennorrhcea 
 of the lacrymal sac. 
 
 Symptoms. — The constant symptom is epiphora, increased 
 by exposure to cold, wind, dust, smoke, etc. There may be 
 fulness in the region of the lacrymal sac; this distention is 
 known as mucocele (Fig. 55, Plate VI). By pressing upon the 
 distended sac, a visdd fluid of whitish, yellowish, or slightly 
 greenish color (depending upon the amount of pus) escapes 
 from the puncta; but sometimes the sac is emptied in the 
 reverse direction, and the accumulation is pressed into the 
 nose. A form of chronic conjunctivitis affecting chiefly the 
 inner canthus (lacrymal conjunctivitis) and blepharitis are 
 frequently present; eczema occurs sometimes, and there may 
 be ectropion. As a result of contamination by micro-organ- 
 isms from the conjunctiva (especially streptococci and pneu- 
 mococci (Figs. 117 and 114, Plate VIII), a purulent injUmi- 
 
70 DISEASES OF LACRYMAL APPARATUS 
 
 mation of the lining of the sac is set up. The infectious 
 character of the accumulation is shown, when any abrasion 
 or ulcer of the cornea exists, by the readiness with which the 
 wound or ulcer becomes infected and hypopyon keratitis 
 results. In operations upon the eye, such a condition is a 
 very frequent cause of infection. 
 
 Course is chronic and extends over years; a long period may 
 elapse before the patient seeks reUef . After the muco-puru- 
 lent material has filled the sac for a long time, there is atrophy 
 of its mucous membrane and the character of the contents of 
 the distended, atonic walls changes; the accumulation be- 
 comes more watery and consists principally of the tears 
 contaminated with an abundance of micro-organisms. There 
 exists constantly the danger of development of lacrymal 
 abscess. 
 
 Etiology. — In most cases there is obstruction of the nasal 
 duct, either from swelling or organic stricture, the result of 
 an affection of the nasal cavity, usually rhinitis. Less fre- 
 quently, nasal polypi and hypertrophy of the inferior tur- 
 binate are causes and, more rarely, ulcerations, caries, and 
 periostitis are responsible. 
 
 The affection is not very imcommon in the new-born and 
 in young infants in whom it is supposed to be due to adhesion 
 of the lining of the duct or congenital obstruction of its 
 lower end. 
 
 Treatment. — In recent and slight cases, we may relieve the 
 epiphora by curing the nasal affection which produces the ob- 
 struction. Locally, stimulating and astringent remedies, such 
 as a solution of zinc sulphate, may be dropped upon the inner 
 part of the eyeball, followed by gentle massage over the sac so 
 as to favor entrance of some of the remedy, after the patient 
 has emptied the sac by pressure. The sac should be washed 
 out with warm and weak solutions of salt, boric acid, or zinc 
 sulphate, using a small syringe with delicate nozzle (Fig. 97). 
 Semi-weekly irrigations of argyrol (5 to 10 per cent.) are used; 
 but there is risk attending the employment of this remedy. 
 
CHRONIC DACRYOCYSTITIS 
 
 71 
 
 since, if for any reason the solution escapes into the surround- 
 ing tissues, permanent staining and other serious consequences 
 may result. Dilatation of the lower pundum is advisable 
 and often a necessary preliminary to syringing; for this 
 purpose we use a fine conical sound, the canaliculus dilator 
 
 Fig. 97. — ^Anel's Lacrymal Syringe. 
 
 (Fig. 95). If the nasal duct is pervious, the solution will 
 enter the nose and escape from the anterior nares when the 
 patient inclines the head forward. 
 
 Conservative treatment as outlined above will be successful 
 in a fair proportion of cases, especially if the nasal affection 
 and the conjunctivitis be looked after; such management is 
 
 Fig. 99. — One of Bowman's Lacrymal Probes. 
 
 almost always sufficient in dacryocystitis of the new-born 
 and young infants. 
 
 If, however, such treatment, conscientiously and persist- 
 ently carried out, is unsuccessful, we may resort to dilatation 
 with probes — either Weber's conical sound (Fig. 98), or 
 Bowman's probes (Fig. 99) which are numbered from 1 to 8, 
 
1 1 
 
 DISEASES OF LACRYMAL APPARATUS 
 
 the largest (8) being about 2 mm. in thickness; they are 
 curved before use. Probes of greater calibre (Theobald's) 
 are sometimes used. Though tlie smallest probes may be 
 passed through the natural opening after dilatation, it is 
 customary to slit the lower canaliculus in advance. Probing 
 is facilitated anil rendered less painful by the preliminary 
 syringing of a few drops of a solution of 2-per-cent. novo- 
 cain in 1 : 3000 adrenalin into the sac and duct. 
 
 To Slit the Canaliculus. — The surgeon stands behind and 
 supports the patient's head against his body, or he may 
 stand in front. Weber's probe-pointed canaliculus knife 
 
 Fig. 100. — Slitting the Lower Canali- FiG. 101. — Slitting the Lower Canali- 
 culus. First Step. cuius. Final Step. 
 
 (Fig. 94) is most frequently used. The lower lid is pulled 
 outward by the thumb of one hand, and with the other the 
 knife is introduced vertically, until it passes the punctum, 
 and then horizontally; its edge is upward and looks toward 
 the ej'cliall so as to cut into the conjunctiva antl not into the 
 integument (Fig. 100). It is pushed horizontally inward 
 until its extremity meets with the firm resistance of the inner 
 bony wall of the sac; then the knife is raised into a vertical 
 position (Fig. 101). 
 
 To Pass Probes into the Nasal Duct. — Commencing with a 
 small size, say a No. 3, we pass this horizontally inward ex- 
 actly as the knife is passed, the surgeon standing behind (or 
 
PROBING THE NASAL DUCT 
 
 73 
 
 in front of) the patient. When the probe reaches the inner 
 wall of the sac, which we can bo certain of when in lifting the 
 probe there is no wrinkling of the skin of the lower lid, it is 
 raised so that its lower entl points toward the furrow between 
 nose and cheek. It is then pushed downward gently, until it 
 reaches the floor of 
 the nasal fossa (Fig. 
 102). If the probe 
 does not pass readily, 
 we must not use force 
 for fear of injuring 
 the wall of the duct 
 or creating a false 
 passage, but with- 
 draw it slightly and 
 try again, or try a 
 smaller or larger size. 
 The probe is left in 
 from fifteen to thirty 
 minutes, and the 
 proceeding is re- 
 peated every other 
 day, gradually using larger probes; then the intervals be- 
 tween probing are increased. 
 
 Sometimes the stricture is cut, a strong, narrow knife (Fig. 
 96) being passed in the same manner as a probe, and the 
 obstruction divided in two or three directions; this is imme- 
 diately followed by probing. 
 
 In some cases leaden or silver styles are passed and left in 
 for days or weeks, being removed from time to time for 
 cleansing. 
 
 Even with all this treatment, permanent cures are rather 
 the exception in severe cases; there will be temporary relief and 
 then the affection returns. The most favorable cases are 
 those in which there is merelj^ swelling of some part of the 
 duct and the condition has not existed for too long a period. 
 
 Fic. 102. -Paasin^ a Probe into the Nasal Duct. 
 
74 
 
 DISEASES OF LACRYMAL APPARATUS 
 
 When co7iiplete occlusion exists, we cannot expect a cure. In 
 such cases and in others of an obstinate nature, we maj' slit 
 both the upper and lower canaJiculi and divide tlie tissue be- 
 tween these two, keeping open the cavity thus formed until 
 there is no long-er any tendency to unite; this converts the 
 sac into an open space which the patient can keep clean. 
 
 In obstinate and long-standing cases in which other measures 
 have failed and the sac is dilated, a lacrymal fistula is jircsent, 
 impermeable stricture exists, or the patient cannot or will not 
 submit to the tedious process of probing, or we wish to pre- 
 pare an eye for operation, radical treatment (extirpation of 
 the sac) is indicated. In such nstances operation is advisable 
 in order to relieve the discomfort of epiphora, to remove the 
 liability to repeated attacks of abscess, and to get rid of an 
 ever-present infectious collection which, when the cornea is 
 affected, becomes a source of danger to the eye. 
 
 Extirpation of the Lacrymal Sac. — Either a general anaes- 
 thetic or local infiltration anaesthesia with 2-per-cent. novocain 
 in 1 : 3000 adrenalin may be 
 employed. A curved incis- 
 ion, commencing just above 
 the internal canthal ligament, 
 which may or may not be di- 
 vided, and passing downward 
 and outward along the orbi- 
 tal margin for 2 cm., divides 
 successively the skin and un- 
 derlying fascia; until the sac 
 is exposed (Fig. 103). Hem- 
 orrhage is annoying, but can 
 be controlled by retractors 
 (special instruments, Muel- 
 ler's and Axcnfeld's, have been devised), bj^ compression, 
 and by the use of adrenalin solution. Using the anterior 
 crest of the lacrymal groove as a gintle, the sac is separated 
 from periosteum with the aid of the handle of a scalpel and 
 
 Fig. 103. — Extirpation of the 
 Lacrymal Sac. 
 
EXTIRPATION OF THE LACRYMAL SAC 75 
 
 blunt scissors, beginning internally, care being taken not to 
 penetrate the wall; its upper extremity is freed and the 
 canaliculi divided; it is cut off as low down in the canal as 
 possible. The excised sac is examined carefully to make 
 sure that no portion has been left behind. The nasal canal 
 is curetted. After thorough disinfection, the edges of the 
 incision are brought together with three sutures, dusted 
 with iodoform, and a dressing applied by means of which 
 pressure is exerted; this is kept on for a few days. There is 
 usually primary union with obliteration of the cavity, and 
 little or no scar ensues. This operation abolishes the con- 
 duction of the tears, but there is generally little annoyance 
 from epiphora, probably through cure of the lacrymal con- 
 junctivitis. 
 
 Incision into the lacrymal sac for treatment or destruction 
 of its lining is now rarely resorted to since extirpation is con- 
 sidered a more certain and better procedure. 
 
 ACUTE DACRYOCYSTITIS 
 
 An acute purulent inflammation of the region of the lac- 
 rymal sac occurring in the course of chronic dacryocystitis, 
 ending in abscess. It is also known as Abscess of the Lacrymal 
 Sac (Fig. 56, Plate VI). 
 
 Symptoms. — The skin over the lacrymal sac becomes red- 
 dened, swollen, and brawny; this condition extends to adjacent 
 portions of the lids and conjunctiva, and is often sufficiently 
 pronounced to lead to a suspicion of erysipelas. There are 
 great pain and tenderness, some fever and constitutional dis- 
 turbance. After two or three days a yellow discoloration 
 appears at a point usually somewhat below the sac, indicating 
 the formation of an abscess. The evacuation of the pus is 
 followed by relief and a subsidence of symptoms. 
 
 The opening may heal completely, and the case again have 
 the symptoms and slow course of chronic dacryocystitis. In 
 other cases the opening persists, often encircled by granula- 
 tions, and the escaping fluid changes its character and be- 
 
76 DISEASES OF LACRYMAL APPARATUS 
 
 comes watery; this constitutes lacrymal fistula. As long as 
 this remains open, the patient is safe; as soon as it closes, he 
 is liable to have a recurrence of abscess. Sometimes merely 
 a minute passage is left, insufficient to admit a probe, from 
 which a drop of fluid escapes from time to time. 
 
 Etiology. — Lacrymal abscess involves not only the sac, but 
 the surrounding cormective tissue as well. The germ-laden 
 contents of the sac find a small defect in the lining, through 
 which they reach the neighboring tissues and excite inflam- 
 mation and suppuration. 
 
 Treatment.— If the case is seen early, we try to prevent the 
 formation of abscess by pressing out the accumulation and 
 syringing with mild antiseptic solutions (boric acid or bi- 
 chloride 1:6000). If this cannot be done on account of the 
 marked swelling and tenderness or is not effective, as is often 
 the case, we hasten the formation of pus by means of hot 
 compresses. 
 
 As soon as fluctuation occurs, we make a Jree incision 
 through the abscess, entering the knife where the pus pre- 
 sents and cutting downward and outward. After evacua- 
 tion, the incision is kept open by a strip of gauze which is 
 changed daily, until all inflammatory signs have disappeared 
 and the fluid is no longer purulent. We try to restore per- 
 meability of the duct, after which the fistula often closes 
 spontaneously. If this does not happen after the duct be- 
 comes pervious, we freshen'and unite the edges of the opening, 
 or cauterize them with silver nitrate or the electro-cautery, 
 or scrape out the track with a sharp curette. In many cases 
 it is advisable to extirpate the sac, but never until all acute 
 symptoms have subsided. 
 
CHAPTER VI 
 
 DISEASES OF THE ORBIT 
 
 Anatomy. — The orbit is formed of bony walls having the shape of a 
 quadrilateral pyramid; the apex corresponds to the optic foramen; the 
 base is directed forward and corresponds to the strong, thick, project- 
 ing, anterior margin. The nasal wall, the thinnest, is formed by the 
 lacrymal bone and the os planmn of the ethmoid; it presents in front 
 the groove for the lacrymal sac. The inner walls of the orbits are 
 almost parallel, but the outer diverge considerably from each other 
 from behind forward. 
 
 The apex or posterior portion of the orbit presents three openings 
 leading to adjacent cavities: (1) the optic foramen, transmitting the 
 optic nerve and the ophthalmic artery; (2) the sphenoidal fissure, trans- 
 mitting the ophthalmic vein, the nerves for the ocular muscles, and the 
 first branch of the trigeminus; (3) the sphenomaxillary fissure, trans- 
 mitting branches of the second division of the trigeminus. 
 
 Besides communicating with the cavity of the skull by means of 
 the openings at the apex, the orbit is surrounded by a number of other 
 cavities. These are the nasal fossse and accessory cavities — the eth- 
 moidal and sphenoidal sinuses, the frontal sinus, and the antrum of 
 Highmore; these relations are important. 
 
 The contents of the orbit consist of the eyeball and optic nerve, the 
 ocular muscles, the lacrymal gland, blood-vessels, and nerves; the 
 spaces between these are filled with fat and fasciae. 
 
 The eyeball is composed of the segments of two spheres; the ante- 
 rior (cornea), about 12 mm. in diameter, is the smaller and more promi- 
 nent; the larger, posterior, corresponds to the sclera. The eyeball 
 measures about an inch in diameter (24.5 mm. from side to side, 24 mm. 
 from before backward, and 23.5 mm. from above downward). 
 
 The orbital fascia is extensive and presents numerous subdivisions. 
 It serves as periosteum to the walls of the orbit (periorbita). A portion 
 closes in the opening of the orbit forming an anterior wall and extend- 
 ing from the margin of the orbit to both tarsi, and to the external and 
 internal tarsal ligaments, thus constituting the septum orbitale. Pro- 
 longations of the orbital fascise surround the muscles and connect them 
 with one another, the lids, and the margins of the orbit. 
 
 In addition, a layer of fascia surrounds the globe from the cornea to 
 the posterior part, separating the organ from the orbital fat and form- 
 
 77 
 
78 
 
 DISEASES OF THE ORBIT 
 
 ing an articular socket, which permits free movement of the eyebaU in 
 every direction. This investment is known as Tenon's capsule. The 
 contiguous surfaces of the sclera and of Tenon's capsule are smooth 
 and lined with endothelium. In this manner a lymph space is formed, 
 known as Tenon's space, which is continuous posteriorly with tha 
 
 eXT RECTUS 
 
 MALAR 
 BONE 
 
 INT. RECTUS 
 
 INF RECTUS 
 
 Fig. 104. — Coronal Section Showing the Orbit and Adjacent Cavities. 
 
 supravaginal space surrounding the external sheath of the optic nerve. 
 Where the tendons of the ocular muscles pierce Tenon's capsule, the 
 latter is reflected upon them, becoming continuous with their fasciae. 
 
 The arteries of the orbit are derived from the ophthalmic. The 
 veins empty into the ophthalmic veins, which pass through the sphe- 
 noidal fissure to the cavernous sinus. The nerves of the orbit are motor 
 and sensory; the motor nerves, the third, fourth, and sixth, supply the 
 ocular muscles; the sensory nerves are the first and second branches of 
 the trigeminus. The ciliary ganglion lies to the outer side of the optic 
 nerve; it receives motor fibres from the third, sensory fibres from the 
 fifth, and sympathetic filaments from the carotid plexus; it gives off 
 the short ciliary nerves which enter the eye at its posterior part. The 
 orbit contains no lymph-vessels or lymphatic glands. 
 
 Affections of the Orbit include periostitis, cellulitis, throm- 
 bosis of the cavernous sinus, tenonitis, pulsating exophthal- 
 
EXOPHTHALMOS 
 
 79 
 
 mos, ocular manifestations of disease of the nasal accessory- 
 sinuses, tumors, and injuries. 
 
 Exophthalmos (proptosis), a protrusion of the eyeball from 
 the orbit, is a common sign in affections of this region (Fig. 
 105). It is caused by inflammations, tumors, and injuries of 
 the orbit, enlargement of the eyeball 
 from various causes, dilatation of 
 adjoining cavities, pulsating exoph- 
 thalmos, thrombosis of the cavernous 
 sinus,-Graves' disease, and sometimes 
 chronic nephritis and acromegaly, and 
 some cases of paralysis and tenoto- 
 mies of the recti muscles. It is apt 
 to produce conjunctival congestion 
 and epiphora; when marked it may 
 cause interference with the mobility of 
 the eyeball, imperfect closure of the 
 lids (lagophthalmos), with resulting 
 keratitis from exposure, ectropion of 
 the lower lid, diplopia (if lateral dis- 
 placement is added), and interference with vision from 
 inflammation and atrophy of the optic nerve. 
 
 Enophthaknos is the recession of the eyeball into the orbit. 
 With the exception of the cases seen in the aged and in ex- 
 treme emaciation, due to the decrease of orbital fat, it is rare. 
 Other causes are cicatricial contraction following orbital in- 
 juries and cellulitis, fracture of the wall of the orbit, paralysis 
 of the sympathetic, and congenital defect. 
 
 OKBITAL PEBIOSTITIS 
 
 An inflammation of the orbital periosteum, either acute or 
 chronic in its course, and either limited to a portion of the 
 margin of the orbit or spreading more deeply. The products 
 of inflammation often consist merely of a thickening of the 
 membrane; sometimes there is a deposit of bone or gumma 
 (syphilis) ; there may be the formation of an abscess, with or 
 
 Fig. 105. — Exophthalmos 
 (Right Eye). 
 
80 DISEASES OF THE ORBIT 
 
 without subsequent caries or necrosis of a part of the wall of 
 the orbit. 
 
 Symptoms. — These depend upon whether the affection runs 
 an acute or a chronic course, the part of the orbit involved, 
 and whether a subperiosteal abscess results. 
 
 The most common variety is that attacking the margin of 
 the orbit. In such a case there may be no other symptoms 
 than pain, tenderness on pressure at the orbital margin, hard 
 immovable swelling in this situation, and some swelling of .the 
 lids and conjunctiva; the amount of constitutional disturb- 
 ance will depend upon the acuteness of the process. Such a 
 case frequently results in complete absorption of the products 
 of inflammation; less commonly, periosteal thickening or bony 
 deposit remains. If, on the other hand, there is pus, a sub- 
 periosteal abscess is developed at the margin of the orbit, 
 which perforates the skin, leaving a. fistula through which the 
 probe detects either bare or necrosed bone. Such a fistula 
 remains open for months until all the dead bone has been 
 extruded, and after it heals there is a depressed scar and 
 sometimes ectropion and lagophthalmos. 
 
 If the periostitis is situated more posteriorly, there will be 
 more pain, and this will be of a deep-seated character and 
 accompanied by tenderness on pressure upon the globe; there 
 will be considerable swelling and redness of the Uds and con- 
 junctiva and sometimes exophthalmos; the constitutional 
 symptoms will be pronounced. Such cases may result in 
 absorption of the products of inflammation, or in periosteal 
 thickening or bony deposit; the diagnosis of this type is often 
 difficult. But if such a deep-seated process goes on to the 
 formation of an abscess, it becomes much more serious and 
 presents the symptoms of orbital cellulitis, from which it fre- 
 quently cannot be differentiated; the pus finds its way to the 
 surface, but this may take some time; cases of this sort, 
 especially if they involve the roof, may be dangerous to life 
 through extension to the cranial cavity and the occurrence 
 of meningitis or cerebral abscess. 
 
ORBITAL PERIOSTITIS 81 
 
 Etiology. — Injuries; tuberculosis (in children); syphilis 
 (tertiary stage, in adults); rheumatism; extension from affec- 
 tions of nasal accessory sinuses. With all causes, traumatism 
 is often the exciting factor. Rheumatic and syphilitic cases 
 usually run a chronic course and produce periosteal thicken- 
 ing without any tendency to suppuration. 
 
 Treatment. — That of syphilis, rheumatism, or tuberculosis, 
 when these are present. Locally, moist, warm compresses. 
 Incision as soon as we suspect suppuration. A deep in- 
 cision by means of a narrow knife, keeping along the wall 
 of the orbit, is indicated early, even before fluctuation, so as 
 to prevent extension to the brain; the opening is drained by 
 means of a strip of iodoform gauze, until pus no longer 
 escapes. Caries and necrosis may require subsequent opera- 
 tive intervention. 
 
 ORBITAL CELIiXJLITIS 
 
 Orbital Cellulitis is an inflammation of the cellular tissue 
 of the orbit, usually terminating in suppuration, in which 
 case it is also known as Orbital Phlegmon or Retrobulbar 
 Abscess. It runs a more or less acute course, generally ac- 
 companied by marked constitutional symptoms. 
 
 Symptoms. — -Great swelling of the lids, chemosis, exophthal- 
 mos, impairment of mobility of eyeball, violent pain in the 
 orbit increased by pressure upon the eyeball; these local signs 
 are accompanied by marked constitutional symptoms, with 
 high fever; cerebral symptoms may be added. Vision may 
 not be affected, but usually it is reduced and it may be 
 abolished owing to the occurrence of optic neuritis followed 
 by atrophy. After these symptoms have lasted about a 
 week pws appears at a certain part of the skin of the lids 
 (usually below the supraorbital margin) and perforates or, 
 less frequently, it may empty into the fornix. After the 
 evacuation of pus, the symptoms subside and the opening 
 heals, often leaving the eye with some permanent damage. 
 
 Occasionally we see mild forms of orbital cellulitis with 
 
82 DISEASES OF THE ORBIT 
 
 very moderate local symptoms, little if any constitutional 
 disturbance and no sequelae; in such cases the exudate is 
 absorbed without formation of pus. 
 
 Complications. — Optic neuritis; less frequently, throm- 
 bosis of the retinal veins and of the cavernous sinus; occa- 
 sionally panophthalmitis. The process may extend to the 
 brain and be fatal. 
 
 Etiology. — Extension of disease of the nasal accessory si- 
 nuses, especially ethmoid, or from neighboring foci such as 
 orbital periostitis or the teeth; injuries and operations of the 
 orbit followed by infection; foreign bodies in the orbit; facial 
 erysipelas; metastasis (pyaemia, puerperal septicaemia, etc.); 
 acute infective diseases, especially influenza; cold (idio- 
 pathic). 
 
 Treatment. — Hot fomentations. Early and deep incision at 
 the spot where we suspect the abscess to be situated, being 
 careful not to injure the orbital contents. Even when we 
 do not strike pus, we relieve tension, promote bleeding, add to 
 the patient's comfort, and prepare a route for the subsequent 
 evacuation of pus; this is then drained with tubing or gauze. 
 Foreign bodies should be removed. Neighboring infecting 
 foci must be exposed and treated. 
 
 Tenonitis, a rare affection, is a serous inflammation of Tenon's capsule 
 resulting in a cure in a few weeks. Its symptoms are moderate swelling 
 of the upper lid, chemosis, slight exophthalmos, limitation of movements 
 of the eye, and some pain on motion of eyeball. It may follow an 
 injury or tenotomy of one of the recti muscles, exposure to cold, be 
 idiopathic, or due to rheumatism or gout. Treatment consists of 
 warm fomentations and the treatment of the rheumatism or gout if 
 present. 
 
 Thrombosis of the Cavernous Sinus (almost always infective) may 
 be due to extension of a thrombus in the orbital veins occurring in 
 orbital abscess, or may be caused by other neighboring pus foci situ- 
 ated in the pharynx, tonsils, teeth, and the nasal accessory sinuses, or 
 may follow erysipelas, caries of the petrous bone, and metastasis in 
 pyaemia and the infective diseases. The signs and symptoms are 
 similar to those of orbital abscess; in addition there are neuroretinitis 
 
NASAL ACCESSORY SINUS DISEASE 83 
 
 and marked distention of the retinal veins and severe cerebral symptoms. 
 The disease is always fatal. 
 
 Pulsating Exophthalmos presents the following symptoms: Exoph- 
 thalmos, pulsation of the eyeball and surrounding parts, bruit heard 
 over the eye and forehead, noises in the head, pain, marked distention 
 of the blood-vessels of the retina, conjunctiva, and lids, and occasionally 
 optic neuritis. Compression of the carotid of the same side causes a 
 diminution or disappearance of the pulsation and bruit. It is most 
 frequently produced by an arterio-venous aneurism involving the 
 internal carotid artery and the cavernous sinus, generally caused by 
 traumatism such as a penetrating wound of the orbit or a severe blow 
 or fall on the head; it may be due to aneurism of the ophthalmic artery 
 or one of its branches, or of the internal carotid, or to a vascular 
 tumor. The condition may be fatal from hemorrhage. Treatment 
 consists in digital or instrumental compression or ligation of the common 
 carotid; or ligation of the ophthalmic veins or the angular vein. Many 
 but not all cases are cured by these means. 
 
 Intermittent Exophthalmos is a rare condition, due to varicose 
 veins in the orbit, in which there is exophthalmos when the head is 
 depressed, followed by a natural position of the eyeball or enophthalmos 
 when the head is erect. 
 
 The Ocular Manifestations of Disease of the Nasal 
 Accessory Sinuses comprise not only affections of the orbit 
 and its contents due to extension, but include characteristic 
 visual defects which are of great value in the diagnosis of cer- 
 tain chronic forms of sinus disease. The accessory sinuses 
 of the nose (frontal sinus, anterior and posterior ethmoidal 
 cells, sphenoidal sinus, and maxillary antrum) surround the 
 orbit, being separated by bony walls which are very thin in 
 spots. They are lined by an extension of the nasal mucous 
 membrane and as a result of such relationship often become 
 infected. Whenever the natural outlet for each sinus becomes 
 blocked, there will be an accumulation of secretion and 
 consequent distention of the walls of the sinus, often with 
 encroachment upon the orbit and exophthalmos. If this 
 retention is of a mucoid character the condition is known as 
 mucocele; if of a purulent character, as empyema. Such a 
 sinusitis may run an acute or a chronic course. 
 
84 DISEASES OF THE ORBIT 
 
 Frontal Sinusitis is often accompanied by a bulging at the 
 upper and inner angle of the orbit with tenderness on pres- 
 sure over this area and sometimes redness of the overlying 
 skin, severe frontal headache and dizziness on stooping. 
 There may be protrusion of the eyeball downward and out- 
 ward, diplopia, cedema of the lids, conjunctival and episcleral 
 congestion, and lacrymation. Orbital periostitis and cellu- 
 litis may result. 
 
 Ethmoiditis may present a tumefaction at the upper and 
 inner part of the orbit with swelling of the integument of 
 the adjacent lids, displacement of the globe downward and out- 
 ward, diplopia, marked pain, conjunctival and episcleral 
 congestion, and lacrymation. The process may involve the 
 orbit, causing periostitis or cellulitis. The affection is thought 
 to be responsible for certain cases of uveitis. 
 
 Disease of the Sphenoidal Sinus is usually associated with 
 ethmoiditis. The walls of this cavity and the optic nerve are 
 contiguous and this close relationship explains the frequent 
 "occurrence of optic neuritis and retrobulbar neuritis in affec- 
 tions of the sphenoidal sinus. Many examples of disease of 
 this sinus (including ethmoiditis) present no external evi- 
 dences of inflammation and yet give well-marked and fre- 
 quent ocular complications among which are optic neuritis, 
 neuroretinitis, and retrobulbar neuritis, leading to optic-nerve 
 atrophy if the cause is not removed. There is frequently 
 present a central, paracentral, or annular color scotoma, which 
 later may become absolute, usually without any or with but 
 little contraction of the visual field. Another fairly constant 
 symptom is enlargement of the blind spot. Asthenopia and 
 deep-seated pain are often complained of. These functional 
 symptoms are important indications for exploring the sphe- 
 noidal and ethmoidal sinuses. 
 
 Antrum Disease is not often accompanied by ocular symp- 
 toms. There may be pain, swelling of the hds, conjunctival 
 congestion, and lacrymation, but involvement of the orbit is 
 rare. 
 
TUMORS OF THE ORBIT 85 
 
 Exophthalmic Goitre. — The exophthalmos and other ocular 
 symptoms accompanying this disease are described in Chap- 
 ter XXVII, p. 415. 
 
 Tumors of the Orbit are of infrequent occurrence; they 
 may arise from the walls or contents of the orbit or spring 
 from neighboring cavities. The symptoms will depend upon 
 the size, position, and jiature of the tumor. Exophthalmos is 
 usually present; the direction of the protrusion and the im- 
 pairment of motion of the eyeball will be determined by the 
 exact situation of the tumor. Pressure upon the optic nerve 
 may cause optic neuritis or retrobulbar neuritis and, later, 
 atrophy. When located forward or after it has reached a 
 certain size, the tumor may be felt by the tip of the finger 
 passed between the margin of the orbit and the eyeball. 
 Benign tumors usually grow slowly and frequently give rise 
 to but few symptoms; malignant tumors are apt to increase 
 in size very rapidly. Benign tumors of the orbit include 
 dermoid cyst, aneurism, angioma, pulsating exophthahnos, 
 meningocele, osteoma, and distention of neighboring cavities. 
 Malignant txmiors are sarcoma (the more common) and 
 carcinoma. 
 
 Benign tumors demanding excision and certain encapsu- 
 lated sarcomata should be removed with preservation of the 
 eyeball, if possible; Kronlein's operation may be resorted to 
 (p. 91). Non-encapsulated malignant tiunors and others of 
 large size, the excision of which would certainly be followed 
 by destruction of the globe, call for exenteration of the orbit 
 (p. 91) with sacrifice of the eyeball even though it possesses 
 useful vision. 
 
 Injuries of the Orbit include contusions, penetrating 
 wounds, foreign bodies, and fracture of the bony walls. 
 A prominent sign is hemorrhage into the orbit, causing 
 exophthalmos and sometimes ecchymosis of the lids and 
 conjunctiva. Contusions may rupture the globe or occasion- 
 ally result in dislocation of the eyeball in front of the lids; 
 such displacement is sometimes produced by gouging with the 
 
86 DISEASES OF THE ORBIT 
 
 thumb in insane patients. Penetrating wounds may destroy 
 the eyeball, injure the optic nerve, causing blindness, or 
 sever some of the muscles, resulting in paralysis and diplopia; 
 if infected, such wounds are followed by orbital abscess. 
 Foreign bodies may be tolerated if aseptic; if infected, sup- 
 puration ensues. Fracture may involve the anterior wall, 
 or the inner wall causing emphysema, or the apex involving 
 the optic canal and injuring the optic nerve; the last may 
 result from direct injury or indirectly (contrecoup) and pro- 
 duce blindness without ophthalmoscopic evidence, followed 
 in a few weeks by atrophy of the optic nerve. 
 
 Treatment consists in cleansing and disinfecting wounds 
 and endeavoring to extract foreign bodies (with the aid of an 
 a;-ray examination). If the situation is such that extensive 
 manipulation would be necessary for its removal, and we have 
 reason to believe that the substance is aseptic (such as shot), 
 it is often better to allow the foreign body to remain. Free 
 exit for secretions must be maintained. A bandage aids in 
 the absorption of blood and air. 
 
 Congenital Anomalies of the Eyeball are rare; they are 
 usually bilateral. Anophthalmos is a small solid or cystic 
 mass occupying the place of the eyeball. Microphthalmos 
 consists of an eyeball of diminished size in all diameters. 
 Buphthalmos (congenital glaucoma) is an increase in size of 
 the eyeball with symptoms of glaucoma, usually resulting in 
 blindness (p. 218). 
 
 OPERATIONS UPON THE EYEBALL 
 
 Enucleation of the Eyeball. — The Instruments Required 
 are: (1) eye speculum (Fig. 345); (2) fixation forceps (Fig. 
 343) ; (3) toothed forceps (Fig. 344) ; (4) curved, blunt-pointed 
 strabismus scissors (Fig. 348); (5) two squint hooks (Fig. 
 347); (6) strong, curved enucleation scissors (Fig. 106); (7) 
 needle holder (Fig. 349); (8) fine, curved needle, and thin 
 black silk. 
 
 Operation. — A general anaesthetic is ordinarily given. After 
 
ENUCLEATION OF THE EYEBALL 
 
 87 
 
 introduction of the speculum, the conjunctiva is divided all 
 around the cornea, as close to its border as possible, and dis- 
 sected back as far as the insertions of the recti muscles. A 
 squint hook is passed beneath the ten- 
 don of the internal rectus, and the lat- 
 ter is divided with the strabismus scissors 
 close to its insertion; then the other 
 straight muscles are cut in the same way, 
 together with the subconjunctival con- 
 nective tissue for some distance beyond 
 the equator. The points of the scissors 
 must always be directed toward the 
 eyeball and the latter stripped as clean 
 as possible to avoid unnecessary removal 
 of tissue. Instead of commencing with a 
 circumcorneal division of the conjunctiva, 
 we may begin with a tenotomy of the 
 internal rectus and then divide the con- 
 junctiva as we pass from tendon to ten- 
 don. The hook is passed around the 
 globe to make sure that the attachments 
 of the muscles have been completely di- 
 vided. The eyeball is then dislocated 
 forward by pressing the speculum back- 
 ward, and thus the optic nerve is put 
 on the stretch (Fig. 107). The enuclea- 
 tion scissors, closed, are passed between 
 sclera and conjunctiva, feeling for the 
 optic nerve; they are withdrawn a little, slightly opened, 
 and the nerve is divided close to the sclera. The eyeball is 
 held between the thumb and index finger of the left hand, 
 and the oblique muscles and other unsevered attachments are 
 divided. The socket is irrigated with a large quantity of 
 bichloride solution, 1 : 5000. The severed ends of the recti 
 muscles are often sutured (internal and external rectus, su- 
 perior and inferior rectus) to one another or to the con- 
 
 FiG. 106.— Enucleation 
 Scissors. 
 
DISEASES OF THE ORBIT 
 
 junctiva to prevent their retraction and thus give better 
 movement to the stump. The conjunctiva is closed either 
 with a single suture, which is passed through its edge at in- 
 tervals and tied like the string of a pouch, or with three 
 
 or more interrupted sutures. 
 The eye is dusted with iodo- 
 form, bandaged, and the pa- 
 tient kept in bed for two days. 
 Care should be taken to 
 avoid rupturing the eyeball, 
 since a collapsed globe makes 
 the operation more difficult. 
 Troublesome hemorrhage may 
 occur; it can be controlled by 
 pressure. When an eyeball 
 containing a malignant growth 
 is enucleated, as much of the 
 optic nerve as possible should 
 be removed. In rare cases in- 
 fection of the wound leads to 
 abscess, thrombosis, and even 
 fatal meningitis. The ten- 
 dency to meningitis is some- 
 what increased in enucleation of suppurating eyeballs; 
 hence many oculists consider panophthalmitis a contrain- 
 dication to enucleation, and postpone operation until after 
 the suppurative process has ceased. 
 
 The Indications for Enucleation are: (1) Injuries of the 
 eyeball, especially those involving the ciliary region, when 
 the eye is blind, or the traumatism so extensive that the 
 form of the e.yeball cannot be preserved; (2) traumatic irido- 
 cyclitis, to prevent sympathetic ophthalmitis; (3) severe pain 
 in a blind eye which cannot be relieved by less radical means; 
 (4) iridocyclitis, phthisis bulbi, and glaucoma, when accom- 
 panied by severe pain or inflammatory symptoms, and when 
 the eye is blind or is certain to become so; (5) malignant 
 
 Fig. 107. — Enucleation of the Eyeball. 
 
EVISCERATION OF THE EYEBALL 89 
 
 tumors, either intraocular or epiocular (excepting small 
 tumors of the iris which can be entirely removed by iridec- 
 tomy); (6) anterior staphyloma, if the eye is blind, trouble- 
 some, and disfiguring; (7) panophthalmitis after the suppura- 
 tive process has ceased; (8) foreign bodies in the eye when 
 they carmot be removed and cause irritation; (9) cosmetic 
 improvement in blind and disfiguring eyes. 
 
 Enucleation with Insertion of an Artificial Globe. — After 
 enucleation, as just described. Tenon's capsule is filled with 
 a glass, gold, or paraffin sphere, or with a piece of fat exsected 
 from any convenient part of the body. The tendons of the 
 recti muscles, the margins of Tenon's capsule, and the con- 
 junctiva are then successively sutured. This method is in- 
 tended to improve the cosmetic effect; when fat is used, this 
 result is accomplished with very little increase in the reaction 
 which follows ordinary enucleation. 
 
 Evisceration of the Eyeball. — In this operation the cornea 
 and entire contents of the eyeball are removed, the sclera 
 alone remaining. 
 
 The Instruments Required are: (1) eye speculum (Fig. 345); 
 (2) fixation forceps (Fig. 343) ; (3) curved strabismus scissors 
 (Fig. 348) ; (4) Graefe knife (Fig. 194) or Beer's knife (Fig. 
 58); (5) sharp curette; (6) needle holder (Fig. 349); (7) small 
 curved needles, catgut and sjlk sutures. 
 
 Operation. — ^After insertion of the speculum, the eye is 
 transfixed just behind the cornea with a Graefe or Beer's 
 knife, which is made to cut its way out at the upper sclero- 
 corneal junction; the other half of the cornea is separated with 
 the scissors. The contents of the eyeball are then removed 
 thoroughly with a sharp spoon, care being taken that nothing 
 but sclera is left. The cavity is irrigated, wiped out, and 
 hemorrhage arrested. The scleral edges are brought together 
 in a vertical line with catgut sutures, and the conjunctiva is 
 united horizontally with silk sutures. 
 
 Recovery is less rapid than after enucleation, and the pain 
 and reaction are greater; the support for an artificial eye 
 
90 DISEASES OF THE ORBIT 
 
 is usually better. The operation maj' be substituted for 
 enucleation after panophthalmitis, but is contraindicated in 
 malignant tumors, foreign bodies, shrunken eyeballs, and 
 sympathetic ophthalmitis. 
 
 Evisceration with Insertion of an Artificial Vitreous 
 (Mules' Operation). — Following evisceration, after the scleral 
 cavity has been cleansed and hemorrhage checked, a hollow 
 sphere of glass (silver, gold, platinum, paraffin) is introduced. 
 This ball must not be too large; its introduction is facilitated 
 by slitting the sclera and by the use of a special inserting 
 instrument. The wound is then closed and dressed as after 
 the ordinary evisceration. There is considerable reaction 
 after this operation; this may recjuire cold compresses. The 
 patient is confined to bed for several days or a week. The 
 stump is undoubtedly superior to that furnished by any 
 other method, but it frequently happens that the ball is 
 extruded; sympathetic ophthalmitis has followed this 
 operation. 
 
 Artificial Eyes (Fig. 108) are worn after enucleation and 
 evisceration, for cosmetic purposes, and to fill out the cavity 
 
 Fig. 108. — Artificial Eyes, a, Outer Surface; b, Inner Surface; c. Section of Shell Eye; 
 d, Section of Snellen ("Reform") Eye. 
 
 left between the lids. They can be worn as soon as the 
 socket is free from inflammation, usually after several weeks. 
 The artificial eye should be washed frequently, and must be 
 removed every night. After a year its surfaces and edges 
 become roughened, and it must be replaced by a new one. 
 When there is a stump of good size, a shell-shaped artificial 
 
ARTIFICIAL EYES 91 
 
 eye may be indicated; but with a small stump or after enu- 
 cleation, the more modern Snellen " reform " artificial eye 
 gives better cosmetic effect; the latter has a certain thickness 
 and is hollow. 
 
 Exenteration of the Orbit is a radical operation resorted to 
 in certain cases of malignant disease. The periosteum and 
 all the contents of the orbit, including the eyeball, are 
 removed. 
 
 Kronlein's Operation consists of a temporary loosening and 
 displacement of the external wall of the orbit for the purpose 
 of exploration and the removal of deep-seated tumors. 
 
CHAPTER VII 
 
 DISEASES OF THE CONJUNCTIVA 
 
 Anatomy. — The conjunctiva is a thin layer of mucous membrane 
 which lines the eyelids and is reflected on to the eyeball, forming a sac, 
 the conjunctival sac (Fig. 182). We distinguish three divisions: (1) 
 The palpebral conjunctiva, covering the under surface of the lids; 
 (2) the ocular or bulbar conjunctiva, coating the anterior portion of the 
 eyeball; and (3) the fornix, the transition portion, forming a fold be- 
 tween lid and globe. The conjunctiva differs somewhat in structure 
 in each of these portions. 
 
 The palpebral conjunctiva is thicker than the other portions. In the 
 greater part of its extent it is closely adherent to the subjacent tarsus, 
 allowing the Meibomian glands to show through. Its surface is smooth, 
 but presents a number of minute projections, or papilla. It is covered 
 with cylindrical epithelium. Its stroma is of an adenoid character, 
 containing a large number of lymph corpuscles, which may in some 
 cases be collected into small rounded masses (lymphoid folUcles). 
 It is a disputed question, however, whether these are normal or are the 
 result of pathological processes. Numerous mucous glands are also 
 found. 
 
 The conjunctiva of the fornix is similar in structiire to that of the lids. 
 It constitutes a very loose fold {relrotarsal fold), insuring great freedom 
 of movement to the eyeball. It is richly suppUed with blood-vessels. 
 This and its lax condition explain its liability to marked swelling in 
 inflammations of the conjunctiva. It has opening into it the lacr3Tnal 
 ducts and numerous mucous glands. 
 
 The bulbar conjunctiva, thin and transparent, covers the anterior sur- 
 face of the eyeball, being loosely attached to the sclera by connective 
 tissue {episcleral tissue), with the exception of the margin representing 
 the boundary between cornea and sclera (limbus), where it is firmly 
 adherent. In structure it resembles the rest of the conjimctiva but 
 contains no glands. It is covered with laminated pavement epithelium 
 which is continued uninterruptedly over the cornea and constitutes 
 its outer layer. Near the inner canthus it forms a crescentic fold (plica 
 semilunaris), the rudiment of the nictitating membrane or third eyelid 
 of the lower animals. 
 
 The vascular supply of the conjunctiva is derived from the blood- 
 vessels of the fornix — the posterior conjunctival (derived from the palpe- 
 
 92 
 
ANATOMY OF THE CONJUNCTIVA 93 
 
 bral) and from the anterior ciliary. The latter pass forward along the 
 recti muscles and pierce the sclera near the limb us to reach the interior 
 of the eye, giving off one set of branches which form vascular loops sur- 
 rounding the cornea and supplying it with nourishment, and another 
 set {anterior conjunctival), which pass backward in the conjunctiva and 
 anastomose with the posterior conjunctival. This arrangement, to- 
 gether with the posterior ciliary arteries and the retinal system of ves- 
 sels, constitutes the entire vascular system of the eye. Thus the bulbar 
 conjunctiva presents two vascular systems — the posterior conjunctival 
 and the anterior ciliary. The nature of the injection in any given case 
 is of some value in locating the seat of the congestion. 
 
 The nerves of the conjunctiva, branches of the fifth, terminate in 
 end-bulbs, and are especially abundant in the palpebral portion. 
 Lymphatic vessels are found in considerable numbers. 
 
 Pinguecula is a small, slightly raised spot of yellowish color 
 situated to the inner and outer sides of the cornea where the 
 conjunctiva is most exposed to wind, dust, etc., especially 
 marked in old people and most conspicuous when the con- 
 junctiva is reddened. It is not formed of fat as its name 
 implies, but of thickening of the conjunctiva due to excessive 
 development of yellow elastic tissue and the deposit of 
 hyaline substance. It never calls for interference. 
 
 Conjunctival and Ciliary Injection. — The differences be- 
 tween conjunctival and ciliary or circumcorneal injection 
 (Plate VII) are as follows: 
 
 Conjunctival Injection. Ciliary Injection. 
 
 1. Derived from posterior con- 1. Derived from anterior ciliary 
 
 junctival vessels. 
 
 2. Accompanies diseases of the 2. Accompanies diseases of the 
 conjunctiva. cornea, iris, and ciUary body. 
 
 3. IVIore or less muco-purulent 3. Often lacrymation, but no 
 or purulent discharge. conjunctival discharge. 
 
 4. Most marked in fornix con- 4. Most marked immediately 
 junctivse. around the cornea; hence called 
 
 ■'circumcorneal." 
 
 5. Fades as it approaches the 6. Fades toward the fornix, 
 cornea. 
 
 6. Bright, brick-red color. 6. Pink or Ulac color. 
 
 7. Composed of a network of 7. Composed of small, straight 
 
94 DISEASES OF THE CONJUNCTIVA 
 
 coarse, tortuous vessels, anasto- vessels, placed deeply, so that the 
 
 mosing freely, and placed super- individual vessels cannot be recog- 
 
 ficially, so that the meshes are nized easily, but are seen indis- 
 
 easily recognized. tinctly as fine, straight lines radi- 
 ating from the cornea. 
 8. Can be moved with the con- 8. Cannot be displaced by 
 
 junctiva by pressure on lower lid. movement of the conjunctiva. 
 
 In severe forms of diseases of the anterior part of the eye 
 these two types of congestion are often found associated, as 
 we would expect when we remember that the two systems of 
 vessels anastomose freely. 
 
 When very pronounced, particularly when there is much 
 venous congestion, ciliary injection assumes a violet color. A 
 form of injection of this sort involves the episcleral tissue 
 between the equator of the eyeball and the cornea, presenting 
 a deeply placed, violet-colored patch seen in scleritis and 
 glaucoma (Fig. Ill, Plate VII). 
 
 Subconjunctival Hemorrhage results in bright or dark 
 red patches, of greater or lesser size, involving more or less 
 of the bulbar conjunctiva (Fig. 112, Plate VII), unaccom- 
 panied by inflammatory symptoms. This condition (ecchy- 
 mosis) is often seen after injuries, operations, and inflamma- 
 tions of the eyeball. It is frequently observed in old persons 
 with brittle blood-vessels, being excited by various straining 
 efforts, such as sneezing, and in children after whooping- 
 cough. Sometimes the hemorrhage occurs without any 
 exciting cause, the subject being unaware of its existence 
 until he notices the discoloration. The hemorrhage itself is 
 of no importance and the blood becomes absorbed within a 
 week or two; the disappearance of the discoloration can, 
 however, be hastened by gentle massage of the affected area 
 with the finger over the lid, using a 1-per-cent. ointment 
 of ammoniated mercury and following this with hot, moist 
 compresses for ten minutes at a time. 
 
 Hyperaemia of the Conjunctiva (Dry Catarrh) is a very 
 common condition which manifests itself in a congestion 
 
HYPEREMIA OF THE CONJUNCTIVA 95 
 
 affecting chiefly the palpebral portion of the conjunctiva. 
 It may be only a transitory condition or it may exist in 
 chronic form, in which case it is often merely the first stage 
 of chronic catarrhal conjunctivitis. 
 
 Etiology — The transitory form is often caused by local 
 irritants such as foreign bodies, dust, wind, smoke, exposure 
 to bright light or to glare, such as exists at the seashore or 
 on the water, or it accompanies acute coryza and hay fever. 
 The chronic form is frequently the result of uncorrected errors 
 of refraction or the use of faulty glasses, misplaced lashes, 
 vitiated or smoky atmosphere, alcoholism, overuse or abuse 
 of the eyes especially with insufficient illumination, or it accom- 
 panies nasal catarrh, blepharitis, and lacrymal obstruction. 
 A recurrent form has been attributed to gout. 
 
 Symptoms. — There is congestion of the palpebral conjunc- 
 tiva with slight swelling and roughness and little or no 
 discharge. The-patient complains of a dry, hot, gritty, smart- 
 ing sensation, the eyes feel tired, water easily, and are uncom- 
 fortable when exposed to light, and the lids feel heavy. These 
 symptoms are most pronounced with near use of the eyes, 
 especially with artificial illumination. 
 
 Treatment consists of removal of the exciting cause, especially 
 the correction of errors of refraction. Irrigation with solu- 
 tion of boric acid, cold compresses, and stimulating drops 
 such as tincture of opium, 1 part to 10 parts of water, will 
 relieve the discomfort. The use of weak solutions of 
 adrenalin and cocaine may be permitted occasionally; but 
 though very grateful, the continuous use of these remedies is 
 harmful. 
 
 CONJUNCTIVITIS 
 
 Inflammations of the conjunctiva are known as conjunc- 
 tivitis or ophthalmia. 
 The varieties are : 
 
 1. Catarrhal: (a) acute, (b) chronic, (c) follicular. 
 
 2. Purulent: (a) ophthalmia neonatorum, (b) gonorrhoea!. 
 
96 DISEASES OF THE CONJUNCTIVA 
 
 3. Membranous: (a) diphtheritic, (b) non-diphtheritic or 
 croupous. 
 
 4. Granular or trachoma. 
 
 5. Phlyctenular. 
 
 ACUTE CATARRHAL CONJUNCTIVITIS 
 
 This is an acute catarrhal inflammation of the conjunctiva 
 accompanied by mucoid or muco-purulent discharge. It is also 
 known as acute muco-purulent and acute simple conjunctivitis. 
 
 Objective Sjrmptoms. — The palpebral conjunctiva and that 
 of the fornix are of a brilliant red color and are swollen (Fig. 
 121, Plate IX). There is usually but slight congestion of 
 the bulbar conjunctiva; but in severe cases this may become . 
 marked, and there may be added oedema of the bulbar con- 
 junctiva (chemosis. Fig. 119), small conjunctival hemor- 
 rhages, and oedema of the lids. The secretion, which is in- 
 creased in amount and altered in character, varies according 
 to the severity of the affection. In mild cases, it is at first 
 watery with some flakes of mucus, later mucoid; in severer 
 forms, it is muco-purulent; in very marked examples, the 
 amount of pus may be so considerable that the character of 
 the discharge, together with the severity of the objective 
 signs, may leave us in doubt for twenty-four hours whether 
 the disease is not the beginning of a purulent inflammation 
 and may prompt us to make a microscopic examination of a 
 smear of the discharge. The secretion accumulates during 
 the night and dries upon the edges of the Jids during sleep. 
 
 Subjective Symptoms. — There are itching and smarting sen- 
 sations referred to the lids; the latter feel hot, heavy, and as 
 though sand or a foreign body were underneath. There is 
 more or less photophobia. There may be some blurring of 
 sight when the altered secretion lies upon the cornea. The 
 symptoms are usually worse toward evening; they vary in 
 severity with the degree of inflammation. The affection 
 may be limited to one eye, but usually both eyes are impli- 
 cated, either from the start or after two or three days. 
 
ACUTE CATARRHAL CONJUNCTIVITIS 97 
 
 Course. — Most patients get well in a, few days, or in a week 
 or two. Sometimes the acute symptoms subside and a sub- 
 acute or chronic catarrhal conjunctivitis remains. Blepha- 
 ritis may be present. In severe cases small, grayish infiltra- 
 tions (catarrhal ulcers) may form at the corneal margin. The 
 coalescence of a number of these may cause a marginal ulcer, 
 which is usually unimportant, superficial, and heals readily, 
 but occasionally becomes deep and serious. Rarely iritis 
 occurs as a complication. 
 
 Etiology. — The disease occurs at all ages and at all times 
 during the year, but is most common in the spring and 
 autumn. The causes may be divided into: 
 
 1. Mechanical — foreign bodies, exposure to wind and dust 
 (automobiling), smoke, etc. 
 
 2. Epidemic — in spring and autumn, dependmg upon the 
 presence of certain micro-organisms — usually the Koch- 
 Weeks bacillus or the pneumococcus. 
 
 3. Infection — through contact with fingers, towels, hand- 
 kerchiefs, etc., of patients suffering from the disease. The 
 discharge is contagious, especially when it is abundant and 
 when it contains much pus; hence the affection often presents 
 a number of examples in the same household or school. 
 
 4. Exanthemata, accompanying or following measles, less 
 frequently scarlatina and smallpox. 
 
 5. Associated with coryza, rose cold, hay fever, and grippe. 
 Clinical Varieties. — Certain forms of this disease are dis- 
 tinguished by qualifying adjectives, indicating the etiology. 
 
 Traumatic Conjunctivitis is the name given to acute catar- 
 rhal conjunctivitis when excited by the presence of a foreign 
 body or by traumatism. Under this head may be included 
 the forms of conjunctivitis due to intense light (photophthal- 
 mia), for example the electric arc light or that used in electric 
 welding {electric ophthalmia), and that produced by reflection 
 from snow {snow blindness). In the cases due to intense 
 light, there are symptoms of conjunctivitis, and, in addition, 
 marked photophobia, lacrymation, intense smarting of the 
 
98 DISEASES OF THE CONJUNCTIVA 
 
 lids, contraction of the pupil, and sometimes oedema of the 
 lids and superficial ulceration of the cornea. 
 
 Lacrymal Conjunctivitis accompanies dacryocystitis; it is 
 generally limited to the inner third of the palpebral and ocular 
 conjunctiva; it is caused by infection from the secretion of 
 the diseased lacrymal sac containing streptococci (Fig. 117, 
 Plate VIII). 
 
 Exanthematous Conjunctivitis is the name given to that 
 variety which is associated with the exanthemata; this form 
 is most commonly seen in measles. 
 
 Acute Epidemic Conjunctivitis (acute contagious conjunc- 
 tivitis), popularly known as "pink eye," is a very contagious 
 form of acute catarrhal conjunctivitis occurring most often 
 in spring and autumn, presenting marked symptoms and pro- 
 fuse discharge and excited by the Koch-Weeks bacillus or the 
 pnemnococcus (Plate VIII). This is the variety which not 
 infrequently gives rise to such severe objective S3Tnptoms 
 including swelling and redness of the lids and copious dis- 
 charge, that one may be in doubt whether the affection is an 
 example of the catarrhal or of the purulent form of conjunc- 
 tivitis. It is advisable, when first called to treat severe cases 
 of this sort, to examine a smear of the conjunctival secretion 
 under the microscope, and to decide definitely upon the 
 nature of the infection only after the responsible organism 
 has been identified. 
 
 Other Clinical Varieties of acute catarrhal conjunctivitis 
 have been classified according to other micro-organisms than 
 those mentioned above, which seem responsible. One form, 
 which attacks chiefly young children and infants, is due to the 
 influenza bacillus. The micrococcus catarrhalis occurs in some 
 cases. Staphylococci are present to a greater or lesser extent 
 in all forms of conjunctivitis. 
 
 Attempts have been made to base the classification of con- 
 junctivitis upon the findings of bacteriological examination 
 of the secretion. But up to the present time no system of 
 nomenclature of this sort has been found practical, since 
 
PLATE VIM 
 
 Fig. 113. — Gonococcus. 
 
 Fig. 114. — Pneumococcus. 
 
 Fig. 115. — Koch-Weeks Bacillus. 
 
 Fig. 116. — Morax-Axenfeld Diplo- 
 bacillus. 
 
 Pig. 117. — Streptococcus. 
 
 Fig. 118. — Diphtheria Bacillus. 
 
 Figs. 113-118. — Micro-Organisms Found in Various Forms of Conjunctival, Corneal, 
 and Lacrymal Disease. (Zeiss in Im., Oc. 4 = 950 X 
 
ACUTE CATARRHAL CONJUNCTIVITIS 99 
 
 mixed infections are encountered so frequently and in only a 
 few varieties of conjunctivitis have the pathogenic micro- 
 organisms been isolated. The normal conjunctival sac is 
 never free from micro-organisms; staphylococci, the xerosis 
 bacillus, and diplococci, morphologically identical with pneu- 
 mococci, are practically always present. 
 
 Follicular Conjunctivitis is considered by some authorities 
 as a variety of catarrhal conjunctivitis, by others as a form or 
 stage of trachoma. It will be described separately. 
 
 Treatment. — Though the disease tends to get well without 
 interference, treatment reduces the duration, adds to the 
 patient's comfort, and prevents the change into subacute or 
 chronic conjunctivitis. Iced compresses should be applied for 
 from fifteen minutes to an hour, three times a day. The con- 
 junctival sac should be irrigated several times a day with 
 solution of boric add or a solution of mercury bichloride 1 in 
 6000. A bland ointment (vaseline or boric acid) is applied 
 to the edges of the lids at night, to prevent them from becom- 
 ing glued together during sleep. A 25-per-cent. solution of 
 argyrol or a 5-per-cent. solution of protargol should be instilled 
 as long as the discharge is abundant. An excellent method 
 is to instil a few drops of the solution of argyrol or protargol, 
 to allow these to remain in the conjunctival cul-de-sac for 
 five minutes, the patient keeping the lids closed, and then to 
 irrigate thoroughly with solution of boric acid; this should be 
 repeated from three to six times a day. A small quantity of 
 bichloride ointment (1 : 3000) placed in the conjunctival sac 
 at night is useful. 
 
 It is important to caution the patient concerning the con- 
 tagiousness of the discharge. 
 
 If the disease shows a tendency to become obstinate or 
 chronic, weak astringent solutions are indicated (zinc, alum, 
 silver nitrate), accompanied by an occasional application of 
 1-per-cent. silver-nitrate solution or the alum stick to the 
 everted lids. 
 
100 DISEASES OP THE CONJUNCTIVA 
 
 CHRONIC CATABRHAL CONJUNCTIVITIS 
 
 A chronic catarrhal inflammation of the conjunctiva, pre- 
 senting somewhat similar symptoms to those found in the 
 acute form, but associated with only slight changes in the 
 quantity and quality of the normal secretion. It is also 
 known as chronic simple conjunctivitis. 
 
 Objective Symptoms. — The conjunctiva of the lids is red- 
 dened and smooth; in old cases it may be hypertrophied and 
 velvety. The secretion is usually but slightly altered, and 
 there is very little increase; there may be enough to glue the 
 eyelids in the morning or to present some dried secretion at 
 the inner canthus; in some cases there is less than the normal 
 amount of secretion. There is apt to be some excoriation at 
 the outer angle. 
 
 Subjective S3rmptoms are the same in kind as in the acute 
 form: Itching, burning, and smarting sensations; a feeling of 
 dryness; an annoyance as though there were a foreign body 
 in the eye; heavy, sleepy feeling in lids which the patient may 
 have some difficulty in keeping open, especially at night; 
 some sensitiveness to light; the eyes water and tire easily. 
 These symptoms are worse at night. 
 
 Course. — ^The disease is probably the most common of 
 ocular affections. It usually occurs in adults, and frequently 
 in old persons. It is apt to be of lengthy duration, lasting 
 some months and even years. 
 
 Complications. — Blepharitis is frequently present. Eczema 
 of the lower lid, and eversion of the inferior punctum pro- 
 ducing epiphora are not uncommon; sometimes ectropion and 
 corneal ulceration. 
 
 Etiology. — It may be the sequel of acute catarrh. It may 
 be caused by improper hygienic surroundings, vitiated atmos- 
 phere (overcrowding), irritating atmosphere (smoke, dust), 
 continuous exposure to wind, insufficient sleep, late hours, 
 alcoholic excesses, exposure of the conjunctiva in ectropion, 
 eye-strain, overuse, local irritation such as trichiasis, chronic 
 
CHRONIC CATARRHAL CONJUNCTIVITIS 101 
 
 dacryocystitis, etc. It is usually bilateral; when due to local 
 irritants it may be unilateral. 
 
 Treatment. — We must endeavor to remove the cause of the 
 inflammation. Locally: Astringent solutions {zinc, borax, 
 alum, tannic acid, silver nitrate gr. /(o or ji to 1 i.); oint- 
 ments of the yellow oxide and ammoniated mercury; silver 
 nitrate, 1 per cent., brushed on the everted lids once a 
 week; the occasional application of the alum or sulphate-of- 
 copper stick; bland ointments to the edges of the lids at 
 night to prevent adhesion and excoriation. As in all chronic 
 catarrhal affections, the remedies must be changed from 
 time to time. 
 
 Diplobacillus Conjunctivitis, a variety of chronic 
 catarrhal conjunctivitis caused by the bacillus of Morax- 
 Axenfeld (Fig. 116, Plate VIII), is subacute or chronic and 
 often tedious in its course and usually occurs in adults. 
 There is moderate redness and swelling of the palpebral con- 
 junctiva and the lid margins, especially at the angles, on 
 which account the affection has been called Angular Con- 
 junctivitis. The symptoms include smarting and itching and 
 a feeling of foreign body in the eye; there is slight, grayish, 
 tenacious discharge, which is found gluing the lashes together 
 upon awakening. Instillations of zinc sulphate (0.2 to 0.4 
 per cent.) or zinc chloride (0.2 per cent.) act as a specific 
 in this form of conjunctivitis. 
 
 FOLLICULAK CONJUNCTIVITIS 
 
 This disease, also known as Follicular Catarrh, is charac- 
 terized by the occurrence of "follicles," with or without the 
 symptoms of catarrhal conjunctivitis (Fig. 123, Plate IX). 
 
 Objective Symptoms. — The conjunctiva of the lower retro- 
 tarsal fold (less commonly also the upper fornix) presents a 
 variable number of small, round or oval, pinkish, translucent 
 bodies, each about the size of a pin-head; wheii abundant they 
 are arranged in rows. These follicles consist of circum- 
 scribed aggregations of lymphocytes (adenoid tissue) identical 
 
102 DISEASES OF THE CONJUNCTIVA 
 
 in structure with the granulations of trachoma; on this ac- 
 count follicular catarrh is sometimes looked upon as an early- 
 stage of trachoma. But this is regarded as unlikely by most 
 authorities since there is neither papillary hypertrophy, cica- 
 tricial changes nor other sequelae, no evidence of contagious- 
 ness, and the affection subsides without leaving any traces. 
 
 The disease presents three clinical types: (1) The presence 
 of follicles accompanied by the signs of acute catarrhal con- 
 junctivitis; (2) the addition of follicles to the objective signs 
 of chronic catarrhal conjunctivitis; and (3) the existence of 
 follicles without any other changes in the conjunctiva — a 
 very frequent form to which the name folliculosis of the 
 conjunctiva is sometimes given. 
 
 Subjective Symptoms vary with the type of disease; they 
 are identical with those of catarrhal conjunctivitis in those 
 varieties which are accompanied by inflammatory manifes- 
 tations. In the form known as folliculosis there will be 
 slight itching, very moderate sensitiveness to light, and some 
 complaint of the eyes tiring easily; in many cases patients 
 do not complain of any symptoms whatever, and the existence 
 of the granulations is discovered accidentally. 
 
 Course. — The disease may be acute but is much more fre- 
 quently chronic; in either case the course is obstinate; in 
 chronic cases the follicles may persist for months and even 
 years. It is sometimes difficult, in acute cases, to differen- 
 tiate between follicular catarrh and granular conjunctivitis, 
 and we may have to await the results of several weeks' 
 treatment in order to decide definitely. At the end of this 
 period, however, it will be possible to decide, since in follicu- 
 lar conjunctivitis the follicles disappear after a time, leaving 
 the conjunctiva in a natural condition, they affect prin- 
 cipally the lower lid, and there are neither corneal nor other 
 complications or sequelae. 
 
 Etiology. — It occurs most frequently in children and in 
 young persons, and is often found in schools, asylums, and 
 other places where there is overcrowding. Poor hygienic sur- 
 
FOLLICULAR CONJUNCTIVITIS 103 
 
 roundings, especially indoor life, anaemia, and errors of refrac- 
 tion are predisposing factors. The various causes of catar- 
 rhal conjunctivitis act as exciting agents. 
 
 Treatment. — The same as that given for acute and chronic 
 catarrhal conjunctivitis, when inflammatory manifestations 
 are present. It is of special importance to correct any inter- 
 ference with the general health and to place such children 
 under the hest hygienic surroundings. Locally, irrigations 
 ■mih.horic-acid solution and the ointment of the yellow oxide 
 of mercury; the occasional use of 1-per-cent. solution of 
 nitrate of silver or of the sulphate-of-copper stick may be of 
 service. When the patient no longer complains of any symp- 
 toms and the follicles persist, they may be allowed to remain 
 and treatment discontinued. 
 
 Purulent Conjunctivitis is an acute purulent inflam- 
 mation usually due to contagion from gonorrhoeal virus. The 
 infecting elements are the gonococci (Neisser) ; they are found 
 in the pus cells and conjunctival epithelium, and are arranged 
 in pairs (diplococci) and generally in colonies (Fig. 113, Plate 
 VIII). The disease is also known as acute blennorrhcea of the 
 conjunctiva. 
 
 Clinical Varieties: (1) Adult Purulent Conjunctivitis or 
 Gonorrhoeal Ophthalmia or Conjunctivitis. (2) Infantile 
 Purulent Conjunctivitis or Ophthalmia Neonatorum (occur- 
 ring in the new-born) . 
 
 GONOBRHCEAL OPHTHALMIA, OB ADULT PUBXTLENT 
 CONJUNCTIVITIS 
 
 Symptoms. — First Stage, Infiltration. — After a period of 
 incubation varying from twelve hours to two days (short in 
 severe cases), there occur great swelling, redness, and tenseness 
 of the lids, so that the latter cannot be opened voluntarily and 
 can be separated only with difficulty. The conjunctiva of the 
 lids and fornix is intensely swollen and reddened, uneven, and 
 in severe cases it may be covered with a membranous deposit; 
 there is chemosis (oedema of the ocular conjunctiva [Fig. 119], 
 
104 
 
 DISEASES OF THE CONJUNCTIVA 
 
 Fig. 119. — Chemosis of the 
 Conjunctiva. 
 
 causing it to swell up around the cornea) and infiltration. 
 The secretion is at first serous, somewhat colored with blood, 
 and containing a little pus. The eye is tender to touch. The 
 patient complains of a hot, smarting pain in the eye and a 
 dull aching in the brow and temple. As a rule only one eye 
 
 is affected. There are some 
 constitutional disturbance, slight 
 fever, and some swelling of the 
 preauricular gland. This stage 
 lasts al^out two days and is 
 followed by the 
 
 Second Stage, Purulent Dis- 
 charge. — The swelling of the litis 
 and conjunctiva antl the chemo- 
 sis diminish and the eye becomes 
 less tender. A very profuse 
 purulent discharge appears and 
 escapes continually from be- 
 tween the lids. This condition 
 continues for two or three weeks, all symptoms gradually 
 diminishing. 
 
 Third Stage, Convcdescence or Papillary SipeUijig. — The ej^e 
 may return to a normal condition in two or three weeks. 
 More frequently, however, there is a stage of papillary swell- 
 ing, a chronic inflammation of the lids; the palpebral and 
 rctrotarsal conjunctiva remaining thickened and red and pre- 
 senting, especially over the tarsus, an uneven granular or 
 velvety appearance, with hypera?mia of the ocular conjunc- 
 tiva, lasting several weeks. 
 
 Course. — The disease is always a serious one, but exhibits 
 various degrees of severity. Cases in which there is slight 
 infection, or in which the disease has been contracted from a 
 chronic gonorrhoea (gleet) are the mildest. The very intense 
 cases have probably been acquired through contagion from 
 the secretion of a very virulent gonorrhoea, and especially 
 from contamination during the early stages. 
 
GONORRHCEAL CONJUNCTIVITIS 
 
 105- 
 
 Etiology. — The disease is always acquired through infec- 
 tion from gonorrheal secretion, either directly, the fingers of the 
 patient transferring the virus from the genitals, or indirectly 
 by means of contaminated towels, etc. 
 
 Complications. — A very frequent and important comphca- 
 tion is corneal ulceration. This begins with a circumscribed 
 grayish infiltration, becoming yellow and breaking down, so 
 that ulcers are formed. The ulcers vary in situation, size, 
 and course. They may be central or marginal; the latter 
 may be confluent, so as to form an annular ulcer. The ulcers 
 may -perforate and this be followed by cicatrization with or 
 without incarceration of the iris, staphyloma, and other 
 sequelae of corneal ulceration. Panophthalmitis may result. 
 Severe and early involvement of the cornea is most common 
 in intense attacks; in such cases, serious and permanent dam- 
 age or loss of the eye is very common. 
 
 Prognosis depends upon the severity of the case, and upon 
 the behavior of the cornea. It is always grave. 
 
 Treatment. — Prophylactic: Great precautions must be 
 observed to prevent infection of the eyes of the physician, 
 nurse, and attendants through spurting of the discharge dur- 
 ing examination or treatment; protecting glasses should be 
 worn whenever exposed to this risk. Contaminated fingers 
 must be carefully disinfected. Materials which have been 
 used for cleansing the eye 
 must be burned. 
 
 The non - affected eye 
 should be protected from in- 
 fection by the application of 
 Buller's shield (Fig. 120). 
 This consists of a watch glass, 
 securely held in place by ad- 
 hesive plaster applied to the 
 side of the nose, the cheek, 
 
 and forehead. The junction of skin and plaster is sealed by 
 a layer of collodion. The centre of the glass is left uncov- 
 
 FiG. 120. — Buller's Shield. 
 
106 DISEASES OF THE CONJUNCTIVA 
 
 ered by plaster to permit inspection of the eye, and a small 
 part of the outer margin of the covering is left free for ven 
 tilation and to prevent the deposit of moisture upon the 
 watch glass. The patient is not allowed to lie upon the 
 non-affected side so that no pus will flow across the nose. 
 
 Treatment of the First Stage: Iced compresses are used more 
 or less continuously, day and night. The eye must be care- 
 fully cleansed and the secretion removed as rapidly as it forms. 
 When very abundant, this will be necessary every quarter or 
 half an hour. For this purpose a saturated solution of boric 
 add is most frequently employed, being allowed to trickle in 
 between the lids from a piece of absorbent cotton dripping 
 with the remedy, or poured in from an undine (Fig. 367); 
 then the secretion which has been washed out is gently wiped 
 off from the margins of the lids. 
 
 The iced compresses may be used continuously at first if 
 grateful to the patient. But when the tense, reddened, and 
 swollen condition of the lids becomes less marked the appli- 
 cation of cold must be reduced to every other hour, or every 
 third hour; too much refrigeration interferes with the nutri- 
 tion of the cornea. When the cornea is involved, we must 
 carefully gauge the amount of cold so as not to use an excess. 
 In the later stages, when there is little swelling, and corneal 
 infiltration or ulceration exists, hot applications may be used 
 in order to improve nutrition by stimulating the flow of 
 blood to the part. Atropine should be instilled. 
 
 Instead of boric acid, other cleansing and antiseptic solu- 
 tions are often used: Mercuric bichloride (1:6000, or 1: 10,- 
 000), sodium chloride (0.75 per cent.), sterilized water, per- 
 manganate of potassium (1: 600). 
 
 During. the stage of purulent discharge, a few drops of 
 25-per-cent. argyrol or 10-per-cent. protargol should be in- 
 stilled every hour; in addition, a 1-per-cent. solution of 
 silver nitrate may be brushed upon the everted conjunctiva 
 once daily; this may be done even though the cornea be 
 implicated. 
 
GONORRHCEAL CONJUNCTIVITIS 107 
 
 In the initial stage, if the disease be very severe, from three 
 to six leeches, applied to the corresponding temple, may be of 
 service. Occasionally there is so much tension that the eye 
 cannot be .cleansed on account of the difficulty in separating 
 the lids, and in addition harmful pressure is exerted upon the 
 eyeball; in such cases it may become necessary to widen the 
 palpebral fissure by a division of the external canthus {can- 
 thotomy, p. 53). It may also be advisable to scarify the 
 ocular conjunctiva if the chemosis and infiltration are extreme 
 and likely to have an injurious effect upon the cornea. 
 
 All manipulations must be most gentle so as to avoid injury 
 to the cornea or perforation when an ulcer is present. 
 
 Treatment of the Later Stages: The applications of silver 
 nitrate should be continued until the patient is well, or until 
 the papillary swelling has persisted for some time. Then, if 
 silver no longer exerts a favorable influence, we may apply 
 glycerole of tannin (5 to 10 per cent.), the alum stick, or 
 sulphate-of-copper pencil once a day. 
 
 The treatment of corneal complications resembles that of 
 infected corneal ulcers, and is described in the next chapter. 
 
 Metastatic Gonorrhceal Conjunctivitis is an uncommon 
 form of inflammation of the conjunctiva excited by the pres- 
 ence of gonorrhceal virus in the circulation and, like arthritis 
 and iritis, is a complication of gonorrhoea. The symptoms re- 
 semble those of catarrhal conjunctivitis of moderate severity, 
 consisting of some swelling and redness of the lids and con- 
 junctiva, a little pain, and limited discharge which is free 
 from gonococci. The affection is usually bilateral, runs its 
 course in two or three weeks, and yields to the ordinary 
 treatment of conjunctivitis (together with iodides internally), 
 as a rule without complications, and never with sequelae. 
 
 OPHTHALMIA NEONATOIITTM OB INFANTILE 
 PUBULENT CONJUNCTIVITIS 
 
 An acute purulent conjunctivitis occurring in the new-born, 
 presenting similar symptoms, complications, and course, and 
 
108 DISEASES OF THE CONJUNCTIVA 
 
 requiring the same treatment as in the gonorrhcsal ophthal- 
 mia of adults. 
 
 Symptoms. — The period of incubation being the same as in 
 adults, the first symptoms are usually noticed on the second or 
 third day after birth; when the onset is later than the fourth 
 day, infection has taken place subsequent to birth. 
 
 The symptoms (Fig. 122, Plate IX) are the same in kind 
 as in the adult form, very often less severe, and more apt to 
 be limited to the palpebral and retrotarsal conjunctiva, 
 hence chemosis is slight. Both eyes are usually involved, 
 but the disease is monolateral in about one-fifth. The 
 cornea is implicated much less frequently, especially if the 
 affection is treated from the start. If seen early, before the 
 cornea is affected, and properly managed, this part very 
 often escapes destruction or damage. 
 
 Prognosis, therefore, vnth early and proper treatment, is 
 generally favorable. 
 
 Etiology. — Infection from vaginitis of the mother during 
 parturition. In rare cases, infection occurs before birth. 
 Sometimes it occurs after the birth of the child, through in- 
 fection from sponges, napkins, towels or fingers of the nurse, 
 which have been in contact with the genitals of the mother. 
 
 Two-thirds of all cases of ophthalmia neonatorum are pro- 
 duced by infection from a gonorrhceal vaginitis; one-third are 
 the result of infection from simple catarrhal vaginitis. In 
 these non-gonorrhoeal cases, gonococci are absent in the con- 
 junctival discharge, though the pneumococcus, bacterium coli, 
 and other germs are found; such forms occur later, run a mild 
 course, and are not usually complicated by corneal ulcers. 
 
 Treatment is similar to that employed in adult purulent 
 conjunctivitis: Iced compresses, frequent cleansing, and instil- 
 lations of argyrol 25 per cent., or protargol 10 per cent., from 
 the start. As soon as the discharge becomes purulent, daily 
 applications of 1-per-cent. solution of silver nitrate continued 
 throughout the stage of papillary sweUing; canthotomy may 
 be necessary; atropine should be instilled. 
 
OPHTHALMIA NEONATORUM 109 
 
 In applying the iced pads, we must be careful not to use 
 them too continuously, as soon as the redness and swelling 
 begin to diminish. In adults, the sensations of the patient 
 guide us to a certain extent, and we use the pads less often 
 when they no longer feel grateful, as happens when the red- 
 ness and swelling subside. In infants, we cannot receive this 
 information; hence great care must be used not to injure the 
 cornea by excessive cooling, especially if there is corneal in- 
 filtration; in such cases, hot compresses are often substituted 
 for the cold. 
 
 The general health of the infant must be looked after, since 
 enfeebled conditions render treatment unsatisfactory and 
 favor corneal complications. 
 
 In the monolateral cases, the child should be kept lying on 
 the affected side so as to favor limitation of the disease to the 
 involved eye, since it is not practicable to seal the healthy 
 eye with a Buller's shield or otherwise. 
 
 Crede's Method of Prophylaxis. — Ophthalmia neonatorum is 
 preventable. Credo's method has made it infrequent in lying- 
 in asylums and in private practice whenever employed. The 
 method consists in cleansing the lids immediately after birth, 
 and instilling one drop of a 2-per-cent. solution of nitrate of 
 silver, thus destroying any gonococci which may have entered 
 the conjunctival sac. This often causes a slight redness of 
 the conjunctiva for a day or two. A 1-per-cent. solution of 
 silver nitrate may be substituted, but 25-per-cent. argyrol 
 or 10-per-cent. protargol, though often used, are not so reli- 
 able for this purpose. Antiseptic irrigation of the vagina of 
 the mother before delivery is also useful as an additional 
 prophylactic measure. 
 
 As a result of Credo's method of prophylaxis, greater atten- 
 tion to the eyes of the new-born, education in this subject, 
 regulation and control of midwives and improved manage- 
 ment, the proportion of total bhndness which twenty-five 
 years ago amounted to 30 per cent, from ophthahnia neona- 
 torum has been reduced to 10 per cent. ; such results, though 
 
110 DISEASES OF THE CONJUNCTIVA 
 
 showing improvement, can be excelled, because blindness 
 from this disease is absolutely preventable. 
 
 Pixrulent Conjunctivitis of Young Girls. — This disease is 
 sometimes met with in young girls in whom the conjunctiva 
 has been infected, directly or indirectly, through an existing 
 vaginal discharge. The secretion may contain gonococci or 
 be free from these. The symptoms resemble those of oph- 
 thalmia neonatoriun but are much less severe, with less ten- 
 dency to involvement of the cornea. The prognosis is good 
 if the usual treatment for purulent conjxmctivitis be properly 
 carried out. 
 
 Catarrhal Conjunctivitis in the New-Bom. — Sometimes we 
 meet with a slight catarrhal conjunctivitis in the new-born, 
 lasting a few days and presenting merely hyperemia, slight 
 swelling, and a little mucoid discharge. These are not ex- 
 amples of ophthalmia neonatorum. But at the start we may 
 be in doubt whether they are not purulent cases, and it will 
 be safer to treat them as such until the character of the in- 
 flammation becomes certain. In such cases, bacteriological 
 examination of the conjunctival discharge is a great aid. 
 
 Membranous Conjunctivitis. — This term comprises 
 two clinical varieties: 1. Diphtheritic Conjunctivitis, and 2. 
 Croupous Conjunctivitis. This subdivision is based upon the 
 clinical pictures presented. The bacteriological findings in 
 the exudation may be, and often are, identical. 
 
 DIPHTHERITIC CONJUNCTIVITIS 
 
 An acute inflammation of the conjunctiva, associated with 
 exudation and infiltration, purulent discharge, with tendency 
 to necrosis of the involved tissues. The disease is rather rare 
 and occurs in children. It spreads by infection. The secre- 
 tion contains the Klebs-LoefHer bacillus (Fig. 118, Plate VIII) 
 and other micro-organisms and. is contagious. 
 
 Symptoms. — The lids are very much swollen, reddened, hot, 
 and tender. The conjunctiva of the lids and fornix is in- 
 
DIPHTHERITIC CONJUNCTIVITIS 111 
 
 tensely inflamed and the tarsal conjunctiva is covered by a 
 grayish-yellow exudation, which also infiltrates the underlying 
 tissues. In this way the lids become hard and cannot be 
 everted. The exudation causes compression, and, as a result, 
 there is a tendency to sloughing of the infiltrated parts. 
 Besides this fibrinous exudation, there is a discharge of a thin, 
 cloudy fluid. The preauricular and submaxillary glands are 
 swollen. With these local signs, there are the prostration and 
 other constitutional symptoms of diphtheria, and there may 
 be local evidences of the disease in other parts of the 
 body. 
 
 At the end of a week the exudation disappears, partly 
 through absorption, partly through necrosis and sloughing, 
 causing a loss of substance covered by granulations. The 
 secretion now becomes more abundant and purulent. 
 
 The defects in the hning of the lid gradually cicatrize, this 
 process causing various deformities: symblepharon, trichiasis, 
 and entropion. There is frequently corneal ulceration. When 
 the diphtheritic process is severe, the infiltration spreads to 
 the ocular conjunctiva, destroys the nutrition of the cornea 
 through pressure, and sight is always lost. 
 
 Etiology. — ^The disease is due to contagion from another 
 case of diphtheria; sometimes a purulent conjunctivitis 
 changes its character and becomes diphtheritic; occasionally 
 it occurs in the course of scarlatina and measles. Though 
 the Klebs-Loeffler bacilli are responsible for the disease, other 
 micro-organisms such as streptococci, pneumococci, and 
 xerosis bacilli are found in the discharge. Some very serious 
 cases having all the clinical manifestations of severe diph- 
 theritic conjunctivitis may present streptococci exclusively. 
 
 The Prognosis in regard to sight is always serious; in 
 regard to life, it depends upon the constitutional effects and 
 general condition of the child. 
 
 Treatment. — Prophylaxis: The precautions described under 
 gonorrhoeal ophthalmia must be employed in this disease, to 
 protect physician, nurse, and attendants. Besides being con- 
 
112 DISEASES OF THE CONJUNCTIVA 
 
 tagious, the disease is infectious; hence the patient shouk 
 isolated; other children must be removed. The unaffe 
 eye must be shielded. 
 
 Treatment of the Affected Eye: Careful cleansing with w 
 antiseptic solutions (boric acid, corrosive sublimate). ( 
 compresses may be applied, but must be used cautiously 
 account of the enfeebled circulation. After a short peri 
 hot compresses are used. When the exudation has separal 
 we apply a 1-per-cent. solution of nitrate of silver. 
 endeavor to prevent sequelce due to cicatrization, by frequ 
 separation of the lids from the globe, and by keeping the i 
 surfaces apart by a roll of absorbent cotton smeared w\ 
 some bland ointment. Corneal ulceration must be trea 
 as described in the liext chapter. Canthotomy and scarif 
 tion are inadyisable. 
 
 Constitutional: We must remember that the eye affect 
 is merely the local manifestation of a constitutional disei 
 Hence the general treatment of diphtheria including in 
 tions of antitoxin and supporting measures, must be can 
 out; the serum should also be instilled into the conju 
 tival sac. 
 
 CROUPOTTS CONJUNCTIVITIS 
 
 A form of inflammation in which there is the deposit of 
 exudation upon the surface of the conjunctiva, upon whicl 
 hardens into a membrane. There is no infiltration into 
 tissues; this constitutes the essential anatomical differe 
 between croupous and diphtheritic conjunctivitis. There 
 no constitutional symptoms such as accompany diphtheria 
 
 Sjrmptoms. — Those of acute catarrhal conjunctivitis; 
 lids and conjunctiva swell and redden but remain soft. AJ 
 a few days a fibrinous rhemhrane forms upon the palpel 
 conjunctiva; when this exudation is pulled off, a raw surf 
 presenting a few bleeding points is seen; under such circi 
 stances the membrane re-forms. The cornea is not invob 
 except in very severe cases, and then usually escapes seri 
 
PLATE VII 
 
 Fic. 109. — Conjunctival Irijcdi 
 
 Fig. 111. — Ciliary and Episcleral 
 Injection. 
 
 Fig. 112, — Subconjunctival 
 Hemorrhage. 
 
 Figs. 109-112.- Types of Conjunctival and Ciliary Congestion. 
 Siibccnjunctival Hemorrhage. 
 
CROUPOUS CONJUNCTIVITIS 113 
 
 injury. The disease lasts two or three weeks and there are 
 usually no sequelae. 
 
 Etiology. — Examination of the membrane or discharge 
 often discloses Klebs-Loeffler bacilli together with other 
 micro-organisms; in these cases the disease is thought to be 
 a mild form of diphtheritic infection. In other examples the 
 diphtheria bacillus is absent. Membrane formation may 
 complicate gonorrhceal conjunctivitis or accompany pneumo- 
 coccus or Koch- Weeks conjunctivitis. In a third class of 
 cases the affection is caused by irritants (mechanical, chemi- 
 cal, or thermic), such as nitrate of silver, acids, lime, molten 
 lead, burns, and injuries in general. 
 
 Treatment. — That of acute catarrhal conjunctivitis. As 
 soon as the membrane shows no tendency to re-form, appli; 
 cations of 1-per-cent. solution of nitrate of silver are useful. 
 Occasionally there is recurrent formation of the membrane for 
 many months. Smears and cultures should be made in every 
 case; when the diphtheria bacillus is found, and in doubtful 
 cases, antitoxin is indicated. 
 
 GRANULAR CONJUNCTIVITIS, TRACHOMA OR 
 GRANULAR LIDS 
 
 A chronic form of conjunctivitis accompanied by hyper- 
 trophy of the conjunctiva and the formation of follicles 
 {"granulations "), with subsequent cicatricial changes. It is 
 a common disease, occurs at all ages, and usually affects both 
 eyes. There is more or less secretion, which is contagious. 
 It is a very important affection on account of its disastrous 
 complications and sequelae, which are responsible for many 
 cases of partial or total blindness. 
 
 Subjective Symptoms. — More or less photophobia, lacry- 
 mation, itching and burning sensations, feeling of foreign 
 body, pain, and visual disturbance. In a good many cases 
 there are no subjective symptoms. 
 
 Objective Symptoms.^There may be swelling of the lids, 
 narrowing of the palpebral aperture, and drooping of the 
 
114 DISEASES OF THE CONJUNCTIVA 
 
 upper lid (from weight and swelling), but very often these 
 external evidences are absent.- There is a variable amount of 
 muco-purulent discharge, marked in recent cases, scanty in 
 chronic forms. The conjunctiva of the tarsus and fornix is 
 reddened, thickened, and uneven, on account of hypertrophy 
 and the occurrence of granulations. The ocular conjunctiva 
 is often somewhat injected. 
 
 Varieties and Pathology. — Basing the subdivision upon 
 variations in appearance, we distinguish three forms: (1) 
 papillary, (2) granular or follicular, and (3) mixed. 
 
 (1) Papillary Form. — A large number of small elevations 
 {papillae) are seen upon the greatly thickened conjunctiva, giv- 
 ing the latter a velvety appearance, or, if the papillae are 
 Jarger, a raspberry-like aspect. This form affects only the 
 tarsal conjunctiva, and chiefly the upper lid. The papillae 
 are caused by the hypertrophied conjunctiva being thrown 
 into folds and depressions; they are covered by an increase 
 in epithelium and the connective-tissue interior is infiltrated 
 with round cells. 
 
 (2) The Granular or Follicular Form presents a prepon- 
 derance of trachoma granules (Fig. 124, Plate IX). These are 
 gray, rounded, translucent bodies showing through the con- 
 junctiva; they have been likened to frog's spawn. They may 
 be small and rounded, larger and oval, projecting or flattened, 
 succulent or warty. They are present principally in the 
 fornix, and when numerous are arranged in rows. In the 
 tarsal conjunctiva they are less numerous, smaller, and less 
 distinct, being hidden by the papillae. Occasionally, tra- 
 choma granules are formed upon the semilunar folds and the 
 bulbar conjunctiva. The granules are rounded collections of 
 cells in a delicate connective-tissue reticulum; the cells are 
 lymphocytes in the peripheral zone, and mononuclear leuco- 
 cytes with a few phagocytes in the interior; the granules 
 usually merge with the surrounding tissue, but in old cases 
 they may present an incomplete capsule. 
 
 (3) The Mixed Form represents the common condition, the 
 
Fig. 121. — Arniv CaiaiThal Con- 
 juuctiviU.T. 
 
 ]''li;. 121'.- -< )phl liahrlia Nroilaloi-iim 
 
 .>-.% 
 
 *^- 
 
 .J _. . -M 
 
 I'"R. 12< F(]lli< III 11 < ciiijuiii In 111- 
 
 I H 124. — 'rrariioma. 
 
 Fi<;. 12S. — Phlyrtcniilar Conjunctivitis. Fig. 126. — Epi.sfleritis. 
 
 Figs. 121-126. Diseases of tiie Conjunctiva and of tiie Episcleral Tissue. 
 
TRACHOMA 115 
 
 papillary and granular varieties being almost always found 
 together, the former more prominent in the palpebral con- 
 junctiva, the latter predominating in the fornix. 
 
 Occasionally trachoma granules undergo a fibrous change 
 and appear as hard, flattened projections upon the tarsal and 
 retrotarsal conjunctiva of the upper lid. 
 
 Course. — The process progresses up to a certain point, and 
 is then followed by cicatricial changes in the conjunctiva 
 {cicatricial stage). This cures the trachoma, and the papillce 
 and granules disappear; but the conjunctiva does not return 
 to a normal condition, the cicatricial changes and contraction 
 leading to certain sequelm; the seriousness of the latter de- 
 pends upon the severity of the process and the amount of 
 hypertrophy and subsequent cicatrization. In the tarsal 
 conjunctiva the cicatricial process causes narrow, whitish 
 bands and scars (Fig. 138, Plate X), sometimes a network; 
 in advanced and severe cases the entire surface may be re- 
 placed by a pale, smooth cicatricial membrane. In the fornix, 
 cicatrization changes the conjunctiva into a pale, bluish- 
 white membrane, and as a result of contraction the transition 
 fold is shortened or disappears. 
 
 Clinical Varieties. — Clinically, trachoma presents a num- 
 ber of variations in its course. Occasionally the invasion is 
 acute, acute trachoma, and accompanied by marked inflam- 
 matory symptoms and profuse purulent discharge; such cases 
 resemble purulent conjunctivitis; the absence of gonococci in 
 the secretion and the presence of the trachoma granules serve 
 to differentiate, but frequently the swelling hides the latter; 
 we may have to wait several days, until the swelling subsides 
 somewhat, before we can decide. 
 
 Most frequently the disease begins insidiously; it may exist 
 unknown for months, before the subjective symptoms become 
 annoying. Most cases of trachoma are chronic in their course 
 and the duration is months or years. 
 
 Not infrequently we meet with a form of trachoma desig- 
 nated by H. Knapp as simple or noninflammatory trachoma, 
 
116 DISEASES OF THE CONJUNCTIVA 
 
 in which there is abundant production of large, soft granula- 
 tions of the follicular variety in the palpebral and retrotarsal 
 portions of the conjunctiva of both lids, without evidence of 
 inflammation and with slight or no symptoms of irritation or 
 discomfort. 
 
 Besides these differences in the intensity of the inflamma- 
 tory symptoms, there are great variations in the amount of 
 change in conjunctiva and cornea. There are mild cases, in 
 which there are but little hjrpertrophy and insignificant cica- 
 tricial changes in the conjunctiva, so that afterward we can 
 scarcely be sure that trachoma has existed; such mild cases 
 usually remain free from corneal comphcations. 
 
 In moderate and severe cases there always remain permanent 
 cicatricial changes, which enable us to diagnose the previous 
 existence of trachoma. When the cornea is implicated, the 
 case is always a serious one. 
 
 Trachoma does not always progress uninterruptedly; there 
 are often intermissions and exacerbations. Relapses are quite 
 frequent, especially when treatment has been discontinued too 
 soon. 
 
 Complications. — The most frequent are pannus and corneal 
 ulceration, both causing disturbance of sight. 
 
 Pannus consists of a newly formed vascular tissue, which 
 usually covers the upper part of the cornea (Fig. 138, Plate 
 X). The affected portion of the cornea presents a cloudy 
 appearance, and is grayish and translucent; its surfa'ce is un- 
 even and vascularized, the blood-vessels springing from the 
 conjunctival vessels at the limbus. The process advances 
 until it covers the upper half of the cornea. Finally, the 
 entire cornea may be covered and vision be redv/;ed to percep- 
 tion of light. Unless subsequent changes occur, complete 
 retrogression is possible, so that the cornea can become trans- 
 parent again. In marked cases iritis is apt to develop. 
 Pannus is not merely due to mechanical irritation, but 
 to a change similar to that which occurs in the conjunctiva; 
 it is a lymphoid infiltration with new blood-vessels be- 
 
SEQUELAE OF TRACHOMA 117 
 
 tween Bowman's membrane and the epithelial layer of the 
 cornea. 
 
 Ulcers of the Cornea occur with or without parmus, leave 
 opacities, interfering with vision according to seat and 
 density. 
 
 Sequelae.— Complete cure occurs usually in mild cases 
 only, or in some of the severer forms when subjected to early 
 treatment. Sequelae are very common, affect the conjunc- 
 tiva, cornea, and lids, and produce permanent disability of 
 the eye. 
 
 1. Trichiasis and entropion result from cicatricial contrac- 
 tion of the conjunctiva with curving of the tarsus; they are 
 more marked in the upper lid. As a result of this distortion 
 of the lid with changes in the position of the cilia, there is 
 mechanical interference with the cornea, causing ulceration. 
 
 2. Ectropion (usually of lower lid) sometimes follows 
 from hypertrophy of the conjunctiva and contraction of the 
 orbicularis. 
 
 3. Symblepharon results from cicatricial contraction of the 
 conjunctiva; when marked, there is obliteration of the fornix. 
 This condition restricts the movements of the eyeball. 
 
 4. Corneal opacities result from pannus and corneal ulcers. 
 After lasting some time, pannus changes into a thia, perma- 
 nent layer of connective tissue. 
 
 5. Staphyloma of the cornea follows in some cases. 
 
 6. Xerosis, a contracted, dry, and scaly state of the con- 
 junctiva, with changes in the cornea, may occur in severe 
 forms. ■ 
 
 Etiology. — Trachoma is caused by contagion from another 
 eye transferred through the secretion. The transfer from one 
 eye to another may take place by the fingers, but usually by 
 towels, handkerchiefs, and the like, which are used in common 
 by many persons. The liability to infection is in direct pro- 
 portion to the amount of discharge; the more profuse the 
 discharge, the greater the danger of infection. The disease 
 spreads most extensively in schools, asylums, and barracks. 
 
118 DISEASES OF THE CONJUNCTIVA 
 
 and among people who live crowded closely together, who are 
 careless in regard to cleanliness, and who are handicapped by 
 bad hygienic surroundings. It is found most frequently among 
 the poorer classes. It is common in Russian and Polish Jews, 
 Hungarians, Italians, the Irish, Japanese, and Chinese. It 
 occurs with especial frequency in certain countries — ^Arabia, 
 Egypt; it is endemic in the latter country and a majority of 
 the natives are afflicted (hence often called Egyptian ophthal- 
 mia). It is supposed that the soldiers of Napoleon added to 
 the prevalence of the disease in Europe upon their return. 
 In Europe it occurs much more extensively in the East than 
 the West, and much more frequently in low lands (Belgium, 
 Holland, Hungary) than in elevated countries (Switzerland). 
 In America it is common among the foreign population of 
 Eastern cities, especially immigrants from Eastern Europe; 
 but it is also fairly common among native AmericaJis, espe- 
 cially in some parts of the Middle West; it is frequently found 
 among Indians, while negroes are rather exempt. 
 
 It seems likely that the contagious principle in the secretion 
 is a micro-organism or its toxin; a number of such have been 
 described, each in turn failing to be accepted as the cause of 
 trachoma. The latest claimants are very small diplococci 
 isolated from the discharge and the follicles and called Tra- 
 choma Bodies (also clamydozoa) ; it is uncertain whether they 
 are protozoa or bacteria, but they are not the specific cause 
 of trachoma since they have also been found in other condi- 
 tions such as non-gonorrhceic ophthalmia neonatorum and in 
 chronic conjunctivitis. 
 
 Treatment consists in an attempt to reduce the inflammatory 
 symptoms and secretion, and to check and remove hyper- 
 trophy of the conjunctiva, thus shortening the duration and 
 diminishing the liability to conjunctival cicatrization and to 
 sequelae. This is accomplished either by the use of certain 
 irritating appUcations, or by mechanical and surgical means. 
 
 Irritating Applications: Sulphate of copper in the form of a 
 crystal or pencil is the favorite local application. Nitrate 
 
TREATMENT OF TRACHOMA 
 
 119 
 
 of silver (1 or 2 per cent, solution), glycerole of tannin (5 to 
 25 per cent.), copper citrate (cuprocitrol) in 5 to 10 per cent, 
 ointment, solution of mercuric bichloride (1: 1000), and the 
 alum stick are also employed. 
 
 Mechanical and Surgical Treatment includes expression, 
 grattage, abscission of the granulations, excision of a strip of 
 the fornix, excision of the tarsus and a strip of the fornix, 
 electrolysis, x-rays, radium, and carbon-dioxide snow. Ex- 
 pression is the most popular of these meehanical methods, 
 and has the widest range of usefulness. The kind of treat- 
 ment best suited depends upon the nature of the case, the 
 presence or absence of inflammatory symptoms, and the 
 stage of the disease. Mechanical treatment is indicated in the 
 granular form of trachoma, with well-marked translucent 
 granulations, when there is an absence of severe 
 inflammatory symptoms, and in the form which 
 Knapp called non-inflammatory. Irritating ap- 
 plications are indicated as supplementary treat- 
 ment to surgical procedures, and for cases of 
 chronic trachoma, in which the granulations are 
 of smaller size, or of the papillary variety, partic- 
 ularly when there is considerable thickening of the 
 conjunctiva. 
 
 In acute forms and in acute exacerbations of 
 chronic cases, when there is much discharge, solu- 
 tion of nitrate of silver, 1 or 2 per cent., is ap- 
 plied to the conjimctiva, the excess being washed 
 away with water or salt solution. In many cases 
 of this sort, however, it is advisable to suspend 
 temporarily all irritative treatment and to pre- 
 scribe cold compresses, instillations of 25-per-cent. 
 solution of argyrol, and mild cleansing and antiseptic washes. 
 
 During the cicatricial stage copper is no longer indicated; 
 the ointment of the yellow oxide of mercury is then of service. 
 
 If treatment is not continued until every trace of hyper- 
 trophy has disappeared, relapses are very common. 
 
 Fig. 127.— 
 
 Sulphate 
 
 of Copper 
 
 Stick. 
 
120 DISEASES OF THE CONJUNCTIVA 
 
 Sulphate of Copper. — The pencil is apphed to the everted 
 Hds once a day, or every other day; it is drawn lightly across 
 the conjunctiva two or three times, but applied only to the 
 hypertrophied portions. The application should include the 
 palpebral portion of the transition fold of the upper lid; in 
 passing the copper stick under the tarsus, the cornea is pro- 
 tected by the lower lid (Fig. 129). The stick of copper sul- 
 phate should have aflat, blunt end, as shown in Fig. 127, and 
 not be pointed ori3onical. After each application, the excess 
 of copper sulphate is washed off with water or solution of 
 boric acid; subsequently iced compresses may be applied for 
 half an hour or longer. This treatment is continued for 
 months, until every trace of hypertrophy has disappeared; 
 after a time the applications are made more lightly and less 
 frequently. Preliminary instillation of holocain may be re- 
 sorted to for diminishing the pain. 
 
 Expression is performed with Knapp's roller forceps, or an 
 instrument of similar construction, by means of which the 
 granulations are squeezed owi between two fluted rollers at the 
 
 Fig. 128. — Knapp'a Roller Forceps for Trachoma. 
 
 end of the shafts (Fig. 128). The operation is painful and a 
 general ansesthetic is required. After eversion of the upper 
 lid, one extremity of the instrument is passed back into the 
 fornix and the other over the tarsus; using moderate com- 
 pression, the forceps is drawn forward, pressing out the con- 
 tents of the granules (Fig. 130). This procedure is repeated 
 until the lid is free from granulations and presents a dark-red 
 surface with small red points. The lower lid is then operated 
 upon in the same manner. After expression, the conjunctiva 
 is often brushed, vigorously with a solution of mercuric bi- 
 chloride. 1 : 500. Care must be taken not to cause abrasions of 
 
EXPRESSION OF TRACHOMA 
 
 121 
 
 the cornea and not to tear the conjunctiva. If the granulations 
 are hard and horny, it may be well to scarify them before 
 using the roller forceps. There are swelling and jDerhaps 
 ecchymosis for two or three days after the operation. Cold 
 compresses and irrigations with solution of boric acid are indi- 
 
 FlG. 129. — Method of Applying the Sul- 
 phate of Copper Stick to the Conjunc- 
 tiva of the Upper Lid. 
 
 Fig. 130. — The Operation of Expression 
 for Trachoma, as Practised upon the 
 Upper Lid. 
 
 cated for a week; then any remaining roughness is treated 
 with gentle applications of the sulphate-of-cop?^^;- crj^stal 
 every other day for a few weeks, or until the lids are normal. 
 The other mechanical or surgical means of treating tra- 
 choma are used much less frequently than expression. Grat- 
 tage consists in scrubbing the granulations, with or without 
 previous scarification, with a stiff toothbrush until all the 
 granules are removed, and then thoroughly rubbing in a solu- 
 tion of mercuric bichloride, 1 : 500. Excision consists in the 
 
122 DISEASES OF THE CONJUNCTIVA 
 
 removal of a strip of the retrotarsal conjunctiva, about 10 
 mm. broad, containing the granules, sometinies including the 
 entire tarsal cartilage. Exposure of the everted conjunctiva 
 to x-rays and to radium and the application of carbon-dioxide 
 snow are also used. 
 
 Operative procedures alone seldom cure trachoma; they 
 must be followed by other measures. But they often shorten 
 the duration of treatment. 
 
 Treatment of Complications. — Recent pannus is best re- 
 lieved by the treatment of the conjunctiva. In addition, we 
 may use atropine occasionally, so as to keep the pupil dilated 
 and prevent posterior synechise, since iritis is frequently 
 present in these cases. If the pannus is very dense, we may 
 apply the sulphate-of-copper stick directly to the cornea. 
 
 In well-marked cases of pannus of long standing, without 
 corneal ulceration, and unaccompanied by much purulent con- 
 junctival discharge, a freshly prepared 3-per-cent. infusion of 
 jequirity is occasionally rubbed into the everted conjunctiva 
 or the powdered drug is dusted upon this surface; a very vio- 
 lent corneal and conjimctival inflammation is set up, accom- 
 panied by the formation of a croupous membrane (iced com- 
 presses are indicated in this stage); upon the subsidence of 
 the process the pannus is often much improved and occasion- 
 ally cured; this remedy must be used with extreme caution, 
 since it has been the cause of destruction of the cornea. 
 Jequiritol, an extract made from the seed, is somewhat safer 
 for this purpose, since the dosage can be controlled. 
 
 The operation of peritomy, the excision of a narrow strip of 
 conjunctiva surrounding the cornea with a view of cutting off 
 the vascular supply, is occasionally performed for the relief of 
 severe cases of pannus. For active ulceration, nitrate of silver 
 is often used, and atropine, if iritis is suspected. 
 
 General Treatment must not be neglected. The eyes should 
 be kept cleansed by the frequent use of solution, of salt, boric 
 acid, or bichloride of mercury (1 : 10,000). The hygienic sur- 
 roundings of the patient should be made as perfect as pos- 
 
TREATMENT OF TRACHOMA 123 
 
 sible, with proper ventilation, plenty of outdoor exercise, and 
 good food. 
 
 Prophylaxis is very important. The patient and his family 
 must be warned of the contagiousness of the secretion, and 
 impressed with the necessity for keeping the patient's hand- 
 kerchiefs, towels, wash basin, etc., apart from those of other 
 persons. In schools, asylums, institutions, and barracks the 
 prevention of epidemics of trachoma is a very serious matter, 
 requiring constant vigilance, careful inspection of every new 
 addition or inmate, and the isolation of trachoma cases so long 
 as the latter are capable of conveying the disease. 
 
 Parinaud's Conjunctivitis is a rare, infectious disease of 
 unknown cause, having for its chief features large reddish and 
 yellowish granulations and small, superficial ulcers in the 
 palpebral conjunctiva, constitutional disturbance, and swell- 
 ing of the pre-auricular gland. It is usually limited to one 
 eye. Prognosis is favorable, cure resulting in a few weeks 
 or months. 
 
 PHLYCTENULAR CONJUNCTIVITIS 
 
 This disease, also known' as Eczematous Conjunctivitis and 
 as Scrofulous Ophthalmia, is a circumscribed inflammation of 
 the conjunctiva, accompanied by the formation of one or 
 more small reddened projections called phlyctenulae. The 
 latter consist of accumulations of lymphoid cells, which soften 
 at their apices, forming small ulcers. The phlyctenulse may 
 appear upon the ocular conjunctiva, and then the disease is 
 called phlyctenular conjunctivitis; they may be foimd upon 
 the cornea, when the affection constitutes phlyctenular kera- 
 titis; or thej'' may occur, and most frequently do occur, at the 
 limbus, and then we speak of phlyctenular keratoconjunctivitis 
 or marginal keratitis. Very frequently they occur in all three 
 situations in the same individual. The pathology, symp- 
 toms, and treatment being the same in all cases, it is con- 
 venient to describe the three varieties collectively under the 
 title of Phlyctenular Ophthalmia, whether the phlyctenules 
 
124 DISEASES OF THE CONJUNCTIVA 
 
 occur in the epithelial layer of the oculaJ conjunctiva or its 
 extension on the cornea. 
 
 Objective S3rmptoms. — The essential sign is the occurrence 
 of one or more small, grayish elevations, or nodules, about the 
 size of a millet seed (1 or 2 mm.), at some part of the con- 
 junctiva or cornea, frequently at the limbus. The phlyc- 
 tenule is surrounded by an area of conjunctival hyperoemia 
 (Figs. 125, Plate IX, and 139, Plate X). The non-affected 
 parts of the ocular conjunctiva are but sUghtly changed from 
 the normal. The phlyctenule soon presents a small ulcera- 
 tion at its apex, which then occupies the level of the surround- 
 ing conjunctiva. It heals without leaving any changes in 
 the conjunctiva. The entire process lasts from a few days 
 to two weeks. 
 
 Occasionally one or more phlyctenules are of large size with 
 purulent contents; such cases have been called pustular 
 ophthalmia. 
 
 Generally, a number of phlyctenulae appear at the same 
 time; in this manner the entire ocular conjunctiva may be 
 reddened; in such cases the palpebral conjunctiva will be 
 congested. The nodules may become absorbed without 
 going through the stage of ulceration. 
 
 When the phlyctenule appears upon the cornea, the infil- 
 trations and subsequent ulcers are usually superficial and heal 
 without the production of lasting changes in the cornea. But 
 sometimes they spread into the corneal substance, and then 
 leave a permanent opacity. Rarely, the ulcer perforates; or 
 a number of ulcers may, by confluence, spread along the 
 surface of the cornea. 
 
 Fascicular Keratitis. — The ulcer resulting from the phlyc- 
 tenule may advance from the margin to the centre of the cor- 
 nea, drawing after it a fascicle of blood-vessels. In this 
 manner there is formed a narrow, red band of vessels, extend- 
 ing some distance over the cornea; at the apex of this fascicle 
 is seen a small, gray crescent, corresponding to the advancing 
 margin of the ulcer, which has healed in the peripheral parts. 
 
PHLYCTENULAR CONJUNCTIVITIS 125 
 
 This form of ulceration always remains superficial; when the 
 process terminates, the blood-vessels gradually disappear and 
 a superficial linear opacity remains. 
 
 Occasionally, as a result of persistent recurrence of phlyc- 
 tenules, the cornea becomes clouded, uneven, and covered by 
 superficial vessels; this condition is known as phlyctenular 
 pannus and usually disappears by absorption. 
 
 The phlyctenule may, in severe cases, involve the deep 
 layers of the cornea, forming a deep infiltration; this either 
 becomes absorbed completely or leaves an opacity of the cor- 
 nea; or it may become purulent and a deep ulcer result. 
 
 There is usually considerable lacrymation; if there is any 
 discharge, it is mucous or muco-purulent and not abundant. 
 As a result of constant lacrymation, there are frequently 
 added blepharitis, excoriations at the external angles, eczema 
 of the lids, ectropion of the lower lid, and occasionally 
 blepharophimosis. 
 
 Subjective S3rmptoms. — Photophobia is marked when the 
 cornea is involved, slight in conjunctival cases. When this 
 symptom is prominent, there is considerable blepharospasm, 
 so that the child will remain in a dark corner or bury its face 
 in a pillow, and the eyes can be examined only with difficulty. 
 There is discomfort, but not usually any pain. 
 
 Course. — The phlyctenules usually occur in crops; before 
 one is completely cured another is apt to appear. In this 
 way the course may become protracted and may extend over 
 weeks. Each phlyctenule lasts from a few days to a week or 
 two. Relapses are very common. Phlyctenulse occur most 
 frequently in children and in yoimg persons, but are also seen 
 in adults; in the latter, a single large phlyctenule may present 
 the local appearances of episcleritis. 
 
 Etiology. — The disease is very common. It seems depen- 
 dent upon some constitutional error. It occurs frequently in 
 children who suffer from the so-called scrofulous diathesis; it 
 is pretty certain that a large proportion of cases are associated 
 with tuberculosis. It is especially frequent among the lower 
 
126 DISEASES OF THE CONJUNCTIVA 
 
 classes, in whom dirt, poor food, and improper hygienic 
 surroundings are contributory factors; also in children debih- 
 tated from disease and in those recovering from the exanthe- 
 mata, especially measles. Improper diet and errors of refrac- 
 tion are predisposing causes. One frequently sees other 
 manifestations of the predisposing diathesis, such as swelling 
 of the cervical lymphatic glands, adenoids, eczema, coryza, 
 blepharitis, chronic otorrhcea, etc. Sometimes, however, the 
 affection occurs in children of the better classes apparently in 
 good health. 
 
 Pathology. — The nodules consist of lymphoid cells situated 
 between the epithelial layer and the sclera and Bowman's 
 membrane, respectively; the epithelial covering is pushed for- 
 ward, softens and is cast off, leaving an ulcer; the loss of 
 substance is finally replaced by epithelium. 
 
 Prognosis is favorable; serious results are uncommon. The 
 phlyctenulse often leave no traces. In some cases corneal 
 opacities of greater or lesser density remain, and if these are 
 central, sight will be interfered with. 
 
 Treatment. — Local: Calomel dusted upon the eyeball once 
 a day; this is believed to be slowly changed to corrosive sub- 
 limate by the action of the tears, and in this way to keep the 
 eye bathed in an antiseptic fluid; calomel should not be em- 
 ployed if the patient is taking iodine, since such a combina- 
 tion produces the very irritating mercuric iodide in the tears. 
 A favorite remedy is the ointment of the yellow oxide of mer- 
 cury (1 or 2 per cent.) ; a piece about the size of a hempseed is 
 deposited in the conjunctival sac and rubbed about with the 
 lids; when there is a great deal of irritation, it is wise to with- 
 hold this ointment until less inflammation exists.' If the 
 symptoms of irritation are very prominent, it is better to 
 irrigate with solution of boric acid, and to apply cold pads if 
 the phlyctenulse involve the conjunctiva, and hot compresses 
 if they form upon the cornea; 25-per-cent. solution of argyrol 
 may be useful under these circumstances, but must not be 
 used too continuously. 
 
PHLYCTENULAR CONJUNCTIVITIS 127 
 
 If there is infiltration or ulceration of the cornea, atropine, 
 hot compresses, and mild antiseptic washes are indicated. If 
 there is fascicular keratitis, the ointment of the yellow oxide 
 of mercury is employed; in such cases we can often cut short 
 the progress of the disease by cauterizing the advancing edge 
 of the ulcer with a fine electro-cautery point (Fig. 141), or 
 with tincture of iodine. Bandages should not be applied; it 
 is only in extreme cases of very deep ulceration that a bandage 
 is indicated. 
 
 In corneal cases, the photophobia and blepharospasm are 
 often very annoying symptoms. Instillation of solution of 
 holocain will give not only temporary relief, but by encourag- 
 ing the opening of the eyes produce a more or less lasting 
 effect in breaking the spasm. Douching the eye with cold 
 water, several times a day, may be effective. If a fissure of 
 the outer canthus is present, touching this with 2-per-cent. 
 solution of silver nitrate, or the stick of copper sulphate, 
 is of value. In extreme and persistent cases of blepharo- 
 spasm, if nothing else answers, canthotomy (p. 54) may be 
 resorted to. 
 
 General treatment is of great importance. Suitable and 
 nourishing diet with avoidance of sweets, improved hygienic 
 surroundings, plenty oi fresh air, and cold sponging and bath- 
 ing are useful. The nose and naso-pharjmx should receive 
 proper treatment. These patients should not be allowed to 
 remain in the house and in the dark, as they are inclined to 
 do on account of the photophobia. Smoked glasses are pre- 
 scribed to relieve this symptom. Calomel (gr. ^ t.i.d.), iron, 
 quinine, and arsenic are useful for internal administration, 
 and cod-liver oil is of great benefit. 
 
 SPRING CATARRH 
 
 A rather uncommon disease of the conjunctiva, of chronic 
 course, lasting for years, continuing during warm weather 
 (more marked in summer than in spring) and disappearing en- 
 tirely or to a great extent with the beginning of winter. It 
 
128 DISEASES OF THE CONJUNCTIVA 
 
 is also known as Vernal Catarrh. The disease occurs chiefly 
 in children, most frequently in boys. It may attack the 
 tarsal or the bulbar conjunctiva, or both. 
 
 Objective Symptoms. — The tarsal conjunctiva presents 
 hard, flattened papillce, separated by furrows, giving a cobble- 
 stone appearance, and is covered by a delicate, bluish-white 
 film. The bulbar conjunctiva shows at the inner and outer 
 portions of the limbus hard, gelatinous hypertrophies, some- 
 times slightly pigmented, which may involve the cornea for a 
 short distance, and which sometimes surround it. There are 
 conjunctival congestion and some mucoid secretion. Either 
 the palpebral, the more common, or the bulbar form pre- 
 dominates. During the winter these changes become less 
 marked or disappear; they return with the advent of warm 
 weather. 
 
 Subjective Symptoms include a feeling of heat, lacrymation, 
 intense itching, and photophobia; these become worse in warm 
 weather and disappear in the winter. 
 
 The pathological changes consist of hypertrophy of the sub- 
 conjunctival connective tissue and of elastic fibres which 
 undergo hyaline degeneration superficially; this gives rise to 
 the bluish-white film; there is also proliferation of the con- 
 junctival epithelium. Eosinophile leucocytes are abundant 
 in the nodules and in the secretion. 
 
 Course. — The disease usually attacks both eyes and lasts in 
 this intermittent way for several years or longer, finally be- 
 coming extinct and leaving no traces behind. Its etiology is 
 unknown. It may be associated with hay fever. The disease 
 is not contagious. 
 
 Treatment. — There is no known cure. The subjective 
 symptoms can be made less annoying by the remedies in use 
 for catarrhal conjunctivitis. The agents most frequently 
 resorted to are boric acid, corrosive sublimate (1:5000), 
 white-precipitate ointment, acetic acid (2 drops of the dilute 
 acid to an ounce of water), and salicylic-acid ointment (1 per 
 cent.). Temporary relief from the distressing subjective 
 
SYMBLEPHAEON 
 
 129 
 
 symptoms may be obtained by the instillation of l-per-cent. 
 solution of holocain in 1 : 10,000 adrenalin, the use of cold 
 compresses, and the wearing of smoked glasses. If the hyper- 
 trophies are of considerable size, they may, occasionally, be 
 removed. Radium, .r-rays, and carbon-dioxide snow have 
 been credited with good results. 
 
 SYMBLEPHAE.ON 
 
 A cicatricial attachment between the conjunctiva of the lid 
 and the eyeball (Fig. 131). It may affect both lids, but 
 usually the lower; sometimes it includes part of the cornea. 
 It is called anterior or 
 partial, when extending 
 bridge-like from lid to 
 globe, leaving a free por- 
 tion of conjunctiva cor- 
 responding to the fornix; 
 posterior, when it in- 
 volves only the fornix; 
 and complete when it af- 
 fects all the conjunctiva. 
 
 Etiology. — It is caused 
 by the junction of two 
 opposing granulating surfaces; hence, it occurs after injuries, 
 especially burns from lime, acids, and molten metal; also 
 after operations; sometimes it follows trachoma, and occa- 
 sionally diphtheritic conjunctivitis. 
 
 Symptoms. — Symblepharon often interferes with the move- 
 ments of the eyeball, and this may cause diplopia. Traction 
 upon the adherent parts excites irritation. In severe cases 
 the cornea is included and sight interfered with; or, if there 
 is inability to close the lids, lagophthalmos and its sequeliB 
 may be present. 
 
 Treatment. — If anterior and not extensive, we divide the 
 band and keep the two raw surfaces from uniting by sepa- 
 rating them daily with a probe until they have cicatrized 
 
 Fig. 131. — Symblepharon. 
 
130 
 
 DISEASES OF THE CONJUNCTIVA 
 
 separately; the interposition of a small roll of absorbent cotton 
 saturated with some bland oil or ointment may aid in this 
 purpose. 
 
 In more severe forms, and in all cases of posterior and com- 
 plete symblepharon, the separated raw surfaces must be cov- 
 ered with conjunctiva or with grafts of skin or mucous mem- 
 brane to keep them from uniting. This may be done (1) by 
 loose?iing the adjacent bulbar conjunctiva and sewing it over 
 the defect, (2) by transplanting pieces of mucous membrane 
 from the lip or from the rabbit's conjunctiva, (3) by skin- 
 flaps passed from adjacent surfaces, and (4) by Thiersch or 
 Wolff skin-grafts, taken from other parts of the body and 
 supported on an artificial eye or piece of sheet lead until 
 adhesion has taken place; the last method is often 
 successful. 
 
 PTERYGIUM 
 
 A triangular fold of membrane, extending from the inner or 
 outer part of the ocular conjunctiva to the cornea (Fig. 132); 
 
 the apex is immovably united 
 to the cornea, the base spreads 
 out and merges with the con- 
 junctiva. 
 
 Symptoms. — When recent, 
 pterygium is rich in blood-ves- 
 sels and hence of a red color ; 
 later it changes into a white, 
 tendinous membrane. It 
 grows slowly toward the centre 
 of the cornea, giving rise to 
 moderate symptoms of conjunctival iri'itation, and it may 
 eventually cover a considerable part of the cornea; finally it 
 becomes stationary. Besides more or less irritation, it 
 causes disfigurement, may restrict motion of the eyeball, and 
 spreads over the cornea, interfering with vision. It is gener- 
 ally situated to the wmer side of the cornea, less frequently 
 
 Fig. 132. — Pterygium. 
 
PTERYGroM 131 
 
 to the outer side or in both situations. It may occur in 
 one or both eyes. 
 
 Etiology. — Pterygium is thought by some to originate from 
 Pinguecula, the process extending to the cornea and drawing 
 the conjunctiva after it. It occurs usually in elderly persons 
 who are exposed to mnd or dicst (farmers, coachmen, masons, 
 sailors). It is uncommon among the better classes. 
 
 Treatment consists in removal by one of a number of differ- 
 ent operative methods. The pterygium may be dissected away 
 and cut off, the conjunctival defect being closed by uniting the 
 upper and lower borders, undermining the conjunctiva if 
 necessary to bring the edges together. The apex of the 
 pterygium must be thoroughly excised from the cornea, and 
 its attachment in this situation scraped or cauterized with the 
 electrcP-cautery, to prevent recurrence. Instead of cutting 
 off the pterygium, it may be dissected from the cornea and 
 some distance beyond and stitched underneath the detached 
 conjunctiva, either above or below; or it may be divided into 
 halves, of which one is transplanted above and the other below, 
 being. held in the conjunctival pocket by a suture. There is 
 a tendency to recurrence; this is less when the membrane is 
 transplanted than when it is simply abscised. 
 
 Pseudo-^terygium is an attachment of a fold of conjunctiva to the 
 cornea as a result of ulceration of the latter; it occurs occasionally after 
 gonorrhoeal and diphtheritic conjunctivitis, burns, and other injuries. 
 Separation from the cornea results in retraction of the conjunctival fold 
 to its normal position. 
 
 INJURIES OF THE CONJUNCTIVA 
 
 These are very common, and include: 
 
 1. Foreign bodies in the conjunctival sac, consisting of dust, 
 iron, coal, or ashes. They usually adhere to the inner surface 
 of the upper lid, causing severe pain and irritation, and are 
 readily removed after eversion of the lid. 
 
 2. Wounds. — Extensive wounds of the conjunctiva should 
 be closed with one or more sutures. 
 
132 DISEASES OF THE CONJUNCTIVA 
 
 3. Burns are quite common, being due to boiling . water, 
 steam, lime, mortar, powder, molten metal, and acids. Fol- 
 lowing the accident a grayish eschar forms; this separates and 
 leaves a granulating surface, which heals by cicatrization; in 
 this way symblepharon often results. Burns of the conjunc- 
 tiva are frequently accompanied by injury to the cornea; the 
 results are then more serious. Treatment consists in com- 
 plete removal of the caustic substance as soon as possible. 
 Solid particles are removed with absorbent cotton or forceps. 
 Then the conjunctival sac is washed out with solutions which 
 tend to neutralize the corrosive substance or render it insol- 
 uble. In the case of lime, mortar, or caustic alkalies, we 
 flush out with a stream of solution of boric acid. If the cor- 
 rosive agent consisted of an acid, the eye is irrigated with a 
 weak solution of sodium bicarbonate. Subsequently we use 
 cold compresses, atropine, and sometimes a bandage. After 
 the loosening of the eschars, we must separate the adhesions 
 frequently. Symblepharon often occurs, notwithstanding 
 the greatest care. 
 
CHAPTER VIII 
 
 DISEASES OF THE CORNEA 
 
 Anatomy. — ^The cornea is the clear, transparent, anterior portion of 
 the external coat of the eyeball; it is neaxly circular, but is slightly 
 wider in the transverse (12 mm.) 
 than in the vertical direction; its ra- 
 dius of curvature is somewhat shorter 
 than that of the sclerotic; the junction 
 of the two is known as the Umbus, but 
 their tissues are in complete contin- 
 uity. The cornea is composed of five 
 layers (Fig. 133), from without inward: 
 (1) Layer of epitheUal cells; (2) Bow- 
 man's membrane; (3) the proper sub- 
 stance of the cornea; (4) Descemet's-: 
 membrane; and (5) a layer of endo- 
 thelium. 
 
 The epithelium covering the front 
 of the cornea is of the stratified va- 
 riety, formed of flattened, scaly epi- 
 thelial cells superficially, of polyg- 
 onal cells beneath these, and of 
 columnar cells most deeply. Prac- 
 tically it is part of the bulbar con- 
 junctiva. 
 
 Bowman's membrane is a thin, 
 homogeneous membrane which sepa- 
 rates the corneal epithelium from the 
 propei: substance of the cornea. Al- 
 though usually described as a separate 
 membrane, it is really a part of the 
 corneal substance, and when highly 
 magnified is seen to be composed of 
 fine fibres which are intimately con- 
 nected with the subjacent layer. 
 
 The proper substance of the cornea, the thickest layer, is formed of 
 connective tissue arranged in lamellae, the planes of which are parallel to 
 the surface of the cornea; these lamellae are connected with one another. 
 
 133 
 
 Pig. 133. — ^Vertical Section of the 
 Cornea, Showing Minute Anat- 
 omy. A, Layer of epithelial cells; 
 B, Bowman's membrane; C, Prop- 
 er substance of the cornea; D, 
 Descemet's membrane; E, layer 
 of endothelium. 
 
134 DISEASES OF THE CORNEA 
 
 The ultimate fibrils of which the lamellae are composed, as well as the 
 different bundles of fibrils forming the lamelte, are held together by 
 means of a transparent cement substance. The corneal substance is 
 traversed by a system of spaces or lacunae, situated in the cement sub- 
 stance separating the lamince, and sending off prolongations in every 
 direction; these form small canals by moans of which the lacuniE of the 
 same plane and those placed above and below communicate. The 
 spaces are filled with branching cells {corneal corpuscles) , the branches of 
 the cells passing into the small canals and communicating with adjoin- 
 ing cells. These cells are known as the fixed corpuscles in contradis- 
 tinction to the leucocytes which move about and are called the wandering 
 cells of the cornea. The proper substance of the cornea passes unin- 
 terruptedly into the sclera. 
 
 Descemel's membrane (the posterior elastic lamina) is a thin, firm, 
 structureless, transparent, and highly elastic layer, placed posterior to 
 
 the proper substance of the cor- 
 nea; at the periphery of the cor- 
 nea it passes over into radiating 
 bundles of elastic fibres which 
 form the ligamenlum peclinatum. 
 Posteriorly, next to the anterior 
 chamber, is a single layer of flat- 
 tened, hexagonal cells, the endo- 
 thelium. 
 
 The cornea is not provided 
 Fig. 134. — Arcus SenUis. with blood-vessels. The capillary 
 
 loops from the anterior ciliary 
 vessels form a ring around the circumference of the cornea. Its nu- 
 trition is provided for by the system of lymph canals just described. 
 It is richly supplied with nerves derived from the ciliary nerves. 
 
 The line between cornea and sclera is known as the limbus. Near 
 the margin of the cornea, just within the sclerocorneal junction, we 
 frequently find an opaque, whitish ring or part of a ring; this is known 
 as the arcus senilis or gerontoxon (Fig. 134) ; it is due to a deposit of fatty 
 granules, and most frequently occurs in advanced age, though oc- 
 casionally it is found in younger persons. 
 
 Inflammations of the Cornea (Keratitis) in general 
 
 present the following: 
 
 Objective Symptoms. — (1) InfdtraUon, with dulness of sur- 
 face and diminution of transparency; this may be followed 
 by (a) complete absor-ption of the infiltration, (b) incomplete 
 
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 u 
 
 ''^^^2 
 
 
 H 
 
 
 
 ^s 
 
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 B 
 
 ^ ,, _ ^SS^^s^S**" 
 
 "^^ 
 
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 IJ _.A '' 
 
 
 • . a 
 
SYMPTOMS OF KERATITIS 135 
 
 absorption, leaving opacities, (c) suppuration, with formation 
 of an ulcer, and (d) cicatrization (repair). (2) Limited or 
 general vascularization, the blood-vessels being derived from 
 the conjunctival loops at the limbus. (3) Circumcorneal in- 
 jection. (4) There is often a complicating conjunctivitis. (5) 
 Neighboring deep parts are frequently involved (iris and 
 ciliary body), as a result of which there may be exudation in 
 the anterior chamber. 
 
 Subjective Symptoms. — Pain, photophobia, blepharospasm, 
 lacrymation, and interference with vision. 
 
 Varieties. — Keratitis may be divided into suppurative and 
 non-suppurative. 
 
 Suppurative Keratitis. — The common forms are (1) phlyc- 
 tenular keratitis, and (2) ulcers of the cornea. The uncom- 
 mon forms are (3) keratitis e lagophthalmo, (4) neuroparaly- 
 tic keratitis, and (5) keratomalacia. 
 
 Non-Suppurative Keratitis. — The common forms are (1) 
 interstitial keratitis, and (2) vasculo-nebulous keratitis (pan- 
 nus). The uncommon forms are (3) vesicular and bullous 
 keratitis, (4) superficial punctate keratitis, (5) keratitis pro- 
 funda, (6) sclerosing keratitis, and (7) band-shaped keratitis. 
 
 Phlyctenular Keratitis has been described under the title 
 Phlyctenular Conjunctivitis (p. 123), and the special symp- 
 toms arising when the cornea is involved have been pointed 
 out. 
 
 TJLCEB OF THE CORNEA 
 
 An infiltration of a certain portion of the cornea, followed 
 by suppuration and loss of substance of the infiltrated spot. 
 The affection is of conamon occurrence. 
 
 Subjective Sjmiptoms. — Pain, photophobia, lacrymation, 
 and blepharospasm. Sometimes these symptoms are slight, 
 or even absent, and yet such a torpid ulcer may be very 
 extensive and serious. 
 
 Objective Symptoms. — ^An ulcer begins with a dull, gray- 
 ish, or grayish-yellow infiltration of a circumscribed portion 
 
136 DISEASES OF THE CORNEA 
 
 of the cornea (Figs. 135 and 136, Plate X) ; suppuration takes 
 place in this area, the superficial layers are cast off, and thus 
 there is loss of substance: The process may progress in two 
 directions: it may either travel over the cornea so as to 
 involve a greater area, or it may become deeper: it may 
 extend both in area and in depth. Very often the advance 
 takes place in one direction, across the cornea; sometimes 
 there is at the same time a tendency to heal at the opposite 
 side, so that the ulcer merely changes its situation (creeping 
 or serpiginous ulcer). There is nearly always more or less 
 grayish infiltration of the cornea immediately surrounding the 
 loss of substance, and considerable ciliary injection. 
 
 If the ulcer is small and superficial, it will cleanse itself in 
 the course of a few days. The destroyed portion of the cor- 
 nea will be cast off, the infiltrated border will become clear, 
 and repair set in; this is accompanied by the appearance of 
 blood-vessels which spring from the limbus; the process ter- 
 minates in cicatrization. When the ulcer is very superficial, 
 the cornea may remain perfectly transparent. But when 
 some of the proper substance of the cornea has been de- 
 stroyed, new connective tissue takes its place, and such a 
 scar is always more or less opaque. The seat of the ulcer 
 may also be marked by a slight depression {corneal facet). 
 
 The detection of the extent of infiltration and ulceration is 
 facilitated by the instillation of a few drops of a 2-per-cent. 
 solution oi fiuorescein, which stains green all such ulcerated or 
 infiltrated parts. 
 
 When the ulcer is deeper, both subjective and objective 
 symptoms are more pronounced, and the complications and 
 sequelse are more serious. Neighboring structures give evi- 
 dences of inflammation: conjunctivitis, congestion of the iris, 
 even iritis and cyclitis with their symptoms, including hypo- 
 pyon. The suppurative process may spread to the interior 
 of the eye, setting up purulent irido-cyclitis or panophthal- 
 mitis with destruction of the eye, especially if the process is 
 virulent. 
 
PLATE X 
 
 ms.i- 
 
 I"ii;. 1:1 "i. — sinipir ricir f.niic Cornoa. 
 
 Fl<;. l:-;r,. -rTi(Vriril rli.r , if tlic Cor- 
 nea V\ ij ll li\ )>'1|)\ DJi. 
 
 Fig. 13.. — .\illi(i-cni I.iucoina 
 
 I ■iraliii-ial Slai.'!' of Tra<ii- 
 nla, Willi l'ani!il.-<. 
 
 ^' ' ' '1 
 
 BtfttlHK "^^S^^^HI 
 
 :.^^ 
 
 
 ""^ 
 
 ^ 
 
 .. . i-.- 
 
 A \ 
 
 Fu,. i:'.;i. — Plil\ rtrnnliir IviTjiliii-;. Fk.;. 140. — Interstiiial Keratitis 
 
 Figs 135-140 — Diseasps of the Cornea. 
 
SYMPTOMS OF ULCER OF THE CORNEA 137 
 
 Hypopyon is a collection of pus in the anterior chamber. 
 The pus is not derived from the ulcer, but is an exudation 
 from the inflamed iris and ciliary body. It collects at the 
 bottom of the anterior chamber (Fig. 136, Plate X), or it 
 may partially or completely fill this space. It may either 
 remain fluid, or when mixed with fibrin it may form a semi- 
 solid, globular mass. 
 
 Such a deep ulcer may heal with no other permanent in- 
 jury except marked corneal opacity, or there may be added a 
 bulging (keratectasia) . Deep ulcers frequently have their 
 course modified by the occurrence of perforation of the cornea, 
 which, in healing, affects the usefulness and safety of the eye 
 in various ways. 
 
 Perforation of the Cornea may or may not be preceded by 
 a protrusion of Descemet's membrane through the floor of the 
 ulcer, forming a small, transparent vesicle (keratocele) . Per- 
 foration may be spontaneous, or it may be caused by in- 
 creased pressure resulting from the blepharospasm, various 
 straining efforts, such as crying, sneezing or coughing, or 
 occasionally by force exerted in examining the eye. The 
 aqueous humor escapes, often carrying the iris into the 
 wound; the eye feels soft; the anterior chamber is obliterated, 
 and iris and lens are in apposition with the cornea. Perfora- 
 tion of the cornea has a favorable effect upon the course of 
 the affection: the subjective symptoms are relieved, and the 
 ulcer begins to heal as a result of diminished tension. 
 
 When the opening closes by cicatrization, the iris may re- 
 gain its normal position. But frequently it continues en- 
 tangled in the perforation, or remains prolapsed, and becomes 
 incorporated with the scar. Such a condition is called an- 
 terior synechia; the dense, white cicatrix to which the iris is 
 attached is known as adherent leucoma (Fig. 137, Plate X). 
 Most frequently only a portion of the iris is drawn into the 
 scar; the pupil is then more or less pear-shaped. Occasion- 
 ally the entire pupillary margin may be adherent, causing 
 both exclusion and occlusion of the pupil. If the iris remains 
 
138 DISEASES OF THE CORNEA 
 
 fastened to a bulging cicatrix of the cornea, the condition is 
 known as corneal staphyloma. 
 
 At the time of perforation, the lens may become dislocated, 
 and occasionally it escapes. When it is pushed forward and 
 lies in apposition with the margins of the opening and then 
 recedes after the anterior chamber is re-established, it fre- 
 quently presents a proliferation of the subcapsular epithelium 
 which has become irritated by the pressure of the lens upon 
 the cornea, forming a white spot upon its anterior surface 
 (Fig. 227), known as anterior capsular or anterior polar 
 cataract. 
 
 Occasionally the perforation fails to close and a fistula of 
 the cornea results; this condition exposes the eye to sub- 
 sequent serious inflammation and jeopardizes its safety. 
 Intraocular hemorrhage may follow a sudden perforation of 
 the cornea and destroy sight. 
 
 Etiology. — Ulcers of the cornea are usually found in adult 
 and aged individuals; phlyctenular ulcers are the only ones 
 which are common in children. Ulcers are much more fre- 
 quent among the lower than among the better classes, and 
 occur often in individuals in whom the general health is poor. 
 
 The process is essentially an infection by various micro- 
 organisms (pneumococci, streptococci, staphylococci, etc., 
 Plate VIII), frequently introduced by the secretion of chronic 
 conjunctivitis, and especially by that of dacryocystitis, when 
 the protecting corneal epithelium has been lost at some spot. 
 
 According to etiology, corneal ulcers may be divided into 
 (a) primary, when starting in the cornea itself, and (b) sec- 
 ondary, when they have extended from adjacent structures 
 — ^most frequently the conjunctiva. 
 
 The exciting causes are: (1) traumatism (foreign bodies, in- 
 juries — often slight, such as the scratch of a finger-nail, mis- 
 placed cilia) ; this is the most frequent cause; (2) conjunctival 
 inflammations (gonorrhceal, trachoma, diphtheritic); (3) 
 phlyctenular keratitis; (4) disturbances in the nutrition of 
 the cornea (paralysis of trigeminus, keratomalacia, glau- 
 
VARIETIES OF CORNEAL ULCER 139 
 
 coma); (5) infection during operations; (6) acute infectious 
 diseases, especially variola; (7) herpes. 
 
 Clinical Forms. — Corneal ulcers occur under many differ- 
 ent forms and these are named according to the etiology, 
 appearance, or course. Some of these have already been 
 considered. Others warranting special mention are: 
 
 (1) Simple Ulcer is small and superficial with symptoms 
 of slight or severe irritation, no tendency to perforation, ter- 
 minating in uncomplicated healing; phlyctenulae and slight 
 injuries often cause such ulcers. 
 
 (2) Central Ulcer is a small superficial grayish defect, situ- 
 ated at or near the centre of the cornea and accompanied by 
 little evidence of irritation. Healing may be prompt but is 
 often slow, with some tendency to recur, leaving opacities or 
 clear facets which, from their central situation, result in 
 much impairment of vision. This form occurs in poorly 
 nourished children and as a complication of trachoma. 
 
 (3) Deep Ulcer is one which shows a tendency to involve 
 the deeper layers and to perforate rather than to spread over 
 the cornea. The symptoms are apt to be marked, the iris is 
 usually involved, and hypopyon is often present; hence the 
 results are usually serious. 
 
 (4) Infected Ulcek (Serpent, Sloughing, or Pneumo- 
 coccus Ulcer), often known as Hypopyon Keratitis, is a very 
 virulent form in which the process spreads over considerable 
 of the cornea and also deeply. It is quite common, especially 
 in warm weather; it occurs almost exclusively in adults, par- 
 ticularly in elderly, debilitated individuals; the cause is an 
 injury, often a slight one, and the infecting agent is the pneu- 
 mococcus to which sometimes other micro-orgallisms are 
 added. The subjective symptoms are usually severe, occa- 
 sionally slight. Accompanied by some swelling of the lids 
 and marked conjimctival and ciliary congestion, a grayish- 
 yellow infiltration appears at or near the centre of the cornea; 
 this changes rapidly to an ulcer with shushing margins; the 
 advancing edge presents a yellowish crescent (Fig. 136, Plate 
 
140 DISEASES OF THE CORNEA 
 
 X); surrounding the ulcer is a cloudy area made up of fine 
 lines; the rest of the cornea is often dull and gray. The ulcer 
 spreads very rapidly, much of the cornea becomes destroyed, 
 and perforation takes place. There is early and intense iritis, 
 and hypopyon is almost always present. Owing to the viru- 
 lence of the process and the accompanying iritis, much dam- 
 age results to the eye: adhesion and prolapse of the iris are 
 frequent, the pupil is often occluded, and iridocyclitis and 
 panophthalmitis are not uncommon; even in favorable cases 
 there will be marked opacity of the cornea and often staphy- 
 loma; there results, therefore, serious impairment of vision. 
 
 (5) Rodent Ulcer (Mooren's Ulcer) is a rare, superficial form, never 
 perforating, which occurs in elderly, enfeebled subjects, sometimes 
 bilateral, of lengthy duration and unknown cause. It starts at the 
 upper edge of the cornea, being limited in the direction of the hmbus 
 by a gray, undermined rim which is its characteristic feature; it is accom- 
 panied by marked irritative symptoms. As soon as cicatrization be- 
 gins there is apt to be a relapse and an advance on the cornea. Thus 
 a succession of extensions and intermissions follow each other and, 
 unless the process is arrested by cauterization, the entire cornea be- 
 comes covered and sight is permanently and seriously interfered 
 with. 
 
 (6) Marginal Ring Ulcer (Annular Ulcer) is one which encircles the 
 periphery of the cornea and, if deep, interferes with its nourishment. 
 Examples of superficial ulcers of this sort are seen in phlyctenular 
 kerato-conjunctivitis (p. 124) as the result of the coalescence of marginal 
 phlyctenules; also in elderly, gouty individuals in whom a number of 
 small ulcers form more or less of a circle but, although accompanied by 
 much irritation and a tendency to relapse, cause little damage. A more 
 serious type is observed occasionally in debiUtated subjects in whom the 
 ulcers are deeper, form a groove encircling the cornea, and tend to perfo- 
 rate; this may also happen as a complication of gonorrhceal ophthalmia. 
 
 (7) Transparent Ulcer (Indolent Ulcer) is the name given to a simple 
 ulcer when its base is transparent or but faintly gray, this pecuharity 
 being due to defective corneal nutrition. It is usually small, superficial, 
 central, shows no tendency to spread or to perforate, occurs chiefly in 
 weak children or in trachoma, and is followed by little or no opacity, 
 but often by a small pit (facet). 
 
 (8) Herpetic Ulcer (Herpetic Keratitis) results from ruptured herpetic 
 vesicles, spreads superficially, presenting either a round, notched margin 
 
ULCER OF THE CORNEA 141 
 
 or a depressed longitudinal furrow which is anjesthetic; the course is 
 slow and there is a tendency to relapses. 
 
 (9) Dendriform Ulcer (Dendritic Keratitis) is a rare and chronic form 
 of superficial ulcer, which commences with a grayish line and spreads 
 by sending out branches which present small knob-like extremities. 
 Not infrequently it is due to malaria. There are irritative symptoms, 
 the cornea may be anaesthetic, and after healing the corneal scars are 
 represented by Unes corresponding to the distribution of the ulcers. 
 
 (10) Catarrhal Ulcer is crescentic, marginal, superficial, and complicates 
 catarrhal conjunctivitis. 
 
 (11) Atheromatous Ulcer is one which develops in old degenerated 
 scars of the cornea. 
 
 (12) Abscess of the Cornea is the pmrulent infiltration in the substance 
 of the cornea which represents the first stage of infected ulcer. The term 
 Ring Abscess of the Cornea refers to an infection, following penetrating 
 wounds and operations, especially cataract extraction, in which a yellow 
 ring develops in the central portion of the cornea, soon followed by ex- 
 tension and destruction of this part, often succeeded by panophthalmitis. 
 
 Treatment may be divided into (1) constitutional, (2) 
 treatment of pre-existing local conditions, (3) local treatment 
 of the ulcerative process. 
 
 Constitutional. — Since ulcers usually occur in persons in 
 whom the general condition is below par, it is necessary to 
 improve the tone of the system by attention to diet, fresh air, 
 hygienic surroundings, condition of the bowels, etc., and often 
 to administer tonics. 
 
 Treatment of Pre-existing Local Conditions. — Foreign bodies 
 are to be removed and other local irritating conditions reme- 
 died. The various forms of conjunctivitis and dacryocystitis 
 must receive careful attention. 
 
 Local Treatment includes atropine (sometimes eserine), 
 holocain, dionine, bandage, hot compresses, antiseptic lotions, 
 scraping, cauterization, paracentesis of the cornea, and divi- 
 sion of the ulcer by Saemisch's method. 
 
 Atropine must be instilled in sufficient quantity to keep the 
 pupil dilated; it has a sedative effect and acts favorably upon 
 the ulcer by diminishing the iritis. One drop of a 1-per-cent. 
 solution may be used three times a day or oftener. When 
 
142 DISEASES OF THE CORNEA 
 
 the ulcer is central, the iris is drawn away from the seat of 
 perforation, and there is less danger of adhesion or prolapse. 
 Wheii the iilcer is peripheral and deep, so that a perforation 
 is imminent, pilocarpine (1 or 2 per cent.) or eserine (one- 
 third of 1 per cent.) may be substituted, for the same reasons. 
 
 Holocain is a valuable remedy for temporarily relieving the 
 pain and photophobia; cocaine must never be used for any 
 length of time since it has an injurious effect upon the cornea. 
 Dionine (2 to 10 per cent.) is also useful for this purpose. 
 
 Protection is afforded by smoked glasses or by a bandage. 
 A lightly-appUed bandage (protective) is not only comfortable, 
 but by keeping the lids closed and immobile it prevents irrita- 
 tion of the ulcer; it also supphes beneficial warmth. With 
 much discharge, the bandage is contraindicated in super- 
 ficial ulcers. But in cases in which perforation of the cornea 
 is liable to occur, a firm (pressure) bandage is applied; this 
 must be removed and replaced several times a day to permit 
 cleansing of the eye and local apphcations. 
 
 Hot Compresses should be applied for half an hour at a 
 time, several times a day; they favor healing of the ulcer. 
 
 Antiseptic Lotions, such as solutions of boric acid, sodium 
 chloride, bichloride of merciu'y (1:6000), act as cleansing 
 agents, and are especially useful when there is much discharge. 
 
 Other Measures are sometimes resorted to: Iodoform or 
 nosophen sprinkled upon the cornea or applied in the form of 
 an ointment, the eye then being bandaged; also subconjunc- 
 tival injections of corrosive sublimate (1 : 5000). Argyrol (25 
 per cent.) and protargol (10 per cent.) are instilled, but the 
 use of these remedies is associated with the risk of a per- 
 manent brown stain at the seat of the ulcer. Ethyl Hydro- 
 cuprein (optochin), a derivative of quinine, is used in 1-per- 
 cent, solution or ointment several times a day, with such 
 benefit in pneumococcus ulcer as to be considered a specific. 
 
 Autogenous Vaccines have been used with some success, 
 especially in infected ulcers. 
 
 To Limit Spreading: If these remedies are insufficient and 
 
TREATMENT OP CORNEAL ULCER 143 
 
 the ulcer spreads, we must destroy the infective focus either 
 by scraping the floor and margins of the ulcer with a small, 
 sharp curette or, better, by cauterizing this area. Cauteriza- 
 tion is effected by tincture of iodine, pure liquid carbolic acid, 
 or by the actual cautery or the electro-cautery. 
 
 ■ Tincture of Iodine offers a very eflicient mode of disinfect- 
 ing and cauterizing corneal ulcers. A small piece of absor- 
 bent cotton is wound firmly upon an applicator so that the 
 end of the cotton tuft will 'be pointed, dipped into tincture of 
 iodine and then exposed to the air for a few seconds so that 
 there is no excess of liquid. It is now brushed upon the 
 ulcer and especially its infiltrated margins, after local anaes- 
 thesia. It is usually necessary to repeat 
 the cauterization a number of times on 
 successive days. 
 
 Electro-Cautery. — ^After thorough anaes- 
 thesia of the eye, one of the electrodes 
 shown in Fig. 141 is placed cold upon 
 the part to be cauterized, the connection 
 made so that the burner assumes a deep 
 red color, and then the connection Electrodes, 
 
 quickly broken. Successive points of the 
 margins of the ulcer are cauterized in this manner, each for 
 a very short period, so as to prevent perforation and the 
 propagation of heat to deeper parts. In the absence of an 
 electro-cautery apparatus a platinum probe fitted in a 
 wooden handle or even a squint hook may be heated in the 
 flame of an alcohol lamp, and used for this purpose. It may 
 be advisable to render the outlines of the ulcer more distinct 
 by the preliminary instillation of a drop of fluorescein solu- 
 tion (p. 136). 
 
 Paracentesis of the Cornea is another valuable measure. 
 This puncture is frequently made with a paracentesis needle, 
 which is provided with a thick shoulder to prevent the instru- 
 ment from penetrating too far (Fig. 142); it may be made 
 with the lance-shaped knife (Fig. 193), or with the Graefe 
 
144 DISEASES OF THE CORNEA 
 
 cataract knife (Fig. 194). After local anaesthesia and fixation 
 of the eyeball, the instrument is passed perpendicularly to the 
 surface through the cornea, near its lower margin, unless the 
 situation of the ulcer requires another site. As soon as its 
 point reaches the anterior chamber, the handle of the instru- 
 ment is depressed and the knife or needle is 
 pushed on horizontally, avoiding injury to the 
 iris or lens, until the incision is about 3 mm. 
 wide. Then it is withdrawn slowly with pres- 
 sure upon the posterior lip of the wound, so as to 
 evacuate the contents of the aqueous chamber 
 gradually. It may be necessary to repeat the 
 paracentesis or to reopen the wound with a 
 probe daily until the ulcer cleanses itself. 
 
 Saemisch's Operation of splitting the ulcer has 
 been replaced to a great degree by the cautery 
 p^acentesis ^^'^ paracentesis, but is useful in some severe 
 Needle. forms of infected ulcers. A Graefe knife is 
 thrust through clear corneal tissue 1 or 2 mm. 
 to the outer side of the ulcer, made to traverse the anterior 
 chamber, and brought out 1 to 2 mm. to the inner side of 
 the ulcer. The edge of the knife is directed forward, the ul- 
 cer is split through its centre, and the hypopyon removed. 
 The incision must be reopened with a probe daily, imtil the 
 ulcer becomes clean. 
 
 After spontaneous perforation of an ulcer, atropine is in- 
 stilled (or eserine if the opening be peripheral), a pressure 
 bandage applied, and perfect rest in the recumbent posture 
 insisted upon. If there is a recent prolapse of the iris, an 
 attempt should be made to return this membrane to its normal 
 position by the gentle use of a probe; failing in this, the pro- 
 lapse of the iris is seized and excised close to the cornea; if 
 there are adhesions to the margins of the opening, these 
 should be freed; the operation has the effect of an iridectomy; 
 sometimes the opening left after excision is covered by a flap 
 made from the adjacent bulbar conjunctiva. Iridectomy 
 
UNCOMMON FORMS OF SUPPURATIVE KERATITIS 145 
 
 may also be indicated if, during the process of healing of a 
 perforation, there is marked increase of tension or bulging of 
 the cicatrix. But if the prolapse has existed for some days it 
 must be allowed to remain; subsequent operative interference 
 may then be indicated. 
 
 After the healing process has become fairly initiated, cer- 
 tain mildly stimulating remedies, such as the ointment of the 
 ammoniated or the yellow oxide of mercury, are used to 
 hasten cicatrization and to clear up the cornea as much as 
 possible. 
 
 Keratitis e Lagophthalmo (Desiccation Keratitis) is due to exposure 
 of the cornea from defective closure of the lids {lagophthalmos) . Under 
 such circumstances the cornea becomes desiccated, the conjunctival 
 secretion and atmospheric dust settle upon it, infiltration follows, and 
 then ulceration of greater or lesser severity. The lower portion of the 
 cornea is most frequently affected, because this part is left uncovered 
 during sleep when the eyeball turns upward. The causes are paralysis 
 of the orbicularis (facial paralysis), marked exophthalmos, various de- 
 formities of the lids, and long-continued exhausting illness. Treatment 
 consists in curing the lagophthalmos if possible, frequent irrigation of 
 the conjunctival sac with cleansing solutions, and closure of the Uds by 
 bandage or plaster; in slight cases it may be sufficient to apply a ban- 
 dage at night. Unless the process has gone beyond certain limits it 
 can be controlled by this plan of treatment. 
 
 Neiiroparalytic Keratitis is an extensive and deep infiltration and 
 ulceration of the cornea observed after paralysis of the trigemirms, 
 disease of the Gasserian ganglion, or its removal for the cure of facial 
 neuralgia. Thp changes are considered to be either trophic due to ex- 
 posure and lodgment of foreign substances upon the insensitive cornea, 
 or caused by other factors. There is no pain or lacrymation, the course 
 is chronic, and the prognosis is unfavorable; there result always 
 opacity and flattening of the cornea and often more serious conse- 
 quences. Treatment consists in keeping the Uds closed with bandage, 
 shield, plaster, or sutures. 
 
 Keratomalacia (Xerotic Keratitis) is the result of lack of nutrition 
 of the cornea. It is an uncommon disease which occurs in badly 
 nourished infants and young children in the course of greatly debilitating 
 diseases. The process begins in the conjunctiva of both eyes; soon the 
 cornea corresponding to the palpebral aperture becomes cloudy and 
 desiccated, ulcerates, and perforates. The great majority of such 
 
146 DISEASES OF THE CORNEA 
 
 patients die from the disease which is responsible for the corneal condi- 
 tion. Treatment consists in measures to increase the general strength; 
 locally, the usual measures for corneal ulcers, especially warm, moist 
 compresses and protective dressings. 
 
 INTERSTITIAL OR PARENCHYMATOUS KERATITIS 
 
 A cellular infiltration of the middle and posterior layers of 
 the cornea, of frequent occurrence in childhood, chronic in its 
 course, not leading to ulceration, but accompanied by more or 
 less inflammation of the uveal tract. It is also known as 
 anterior uveitis. 
 
 Objective Symptoms. — The affection begins either in the 
 centre or at the margin of the cornea. If it starts in the 
 centre, this part will present a grayish infiltration, the super- 
 ficial layers at first retaining their normal lustre; this central 
 patch soon spreads so that the whole cornea becomes impli- 
 cated. If it commences at the periphery, one or more grayish 
 spots are seen, which soon spread toward the centre and in- 
 volve all the cornea. After the infiltration has become 
 general, the cornea will become softened, of a dense grayish or 
 sometimes yellowish-gray color, so that the iris can be seen 
 only with difficulty, and vision is reduced to little more than 
 perception of light. The surface of the cornea is now steamy 
 and resembles ground glass. At this period, or even before, 
 deep-seated blood-vessels (derived from the anterior ciliary) 
 make their appearance and pervade more or less of the cornea 
 (Fig. 140, Plate X), the advent of the blood-vessels giving the 
 limbus a red and swollen appearance; they cover either the 
 periphery, circumscribed sectors, or the whole cornea. This 
 vascularization gives rise to a dirty-red or yellowish-red dis- 
 coloration, which is known as the salmon patch. The prog- 
 ress thus far is accompanied by irritative symptoms and ciliary 
 congestion and lasts one or two months. 
 
 The inflammation then begins to subside. The periphery 
 of the cornea clears up, the blood-vessels become fewer, the 
 irritative symptoms disappear, and vision improves. Several 
 months or even a longer period is consumed in this process, 
 
INTERSTITIAL KERATITIS 
 
 147 
 
 the centre of the cornea being the last portion to clear. In 
 favorable cases, after a year or more, nothing but a very faint, 
 central opacity and evidences of a few minute peripheral ves- 
 sels can be found. 
 
 Not all cases will, however, run such a benign course. The 
 anterior portion of the uveal tract is regularly involved. In mild 
 cases, this will consist 
 merely in congestion 
 of the iris. But in 
 more serious types 
 there will be iritis, 
 choroiditis, cyclitis, and 
 changes in the vitreous; 
 in such cases, after the 
 cornea has become less 
 opaque, we may find 
 evidences of these in- 
 flammations, in the 
 form of adhesions of 
 the iris to the lens 
 (posterior synechiae), 
 changes in the iris and 
 choroid, opacities of 
 the vitreous, and even 
 occlusion and exclu- 
 sion of the pupil. 
 Keratectasia may also 
 follow. So that more 
 or less serious impair- 
 ment of sight may ensue in unfavorable cases. Further- 
 more, the clearing-up process in the cornea may come to a 
 standstill, leaving a dense opacity. 
 
 Subjective Symptoms. — During the period of infiltration 
 and vascularization there will be photophobia, lacrymation, 
 pain, and interference with vision, the intensity usually 
 depending upon the severity of the process; these 
 
 Fig. 143. — From a Photograph of a Patient, the 
 Subject of Interstitial Keratitis, exhibiting the 
 Signs of Inherited Syphilis, including Hutchin- 
 soniau Teeth. 
 
148 DISEASES OF THE CORNEA 
 
 symptoms gradually subside during the progress of 
 absorption. 
 
 Both eyes are usually involved; frequently the inflamma- 
 tion in the second eye commences after that in the first has 
 existed for some weeks or months. In the exceptional cases 
 occurring in adults, the disease is more apt to be unilateral. 
 
 Etiology. — The disease usually occurs between the fifth and 
 fifteenth years, less commonly after this period, and rarely 
 after thirty. The great majority of cases are due to inherited 
 syphilis; in few instances it depends upon acquired syphilis, 
 tuberculosis, or occurs without known cause. In many cases 
 there will be other 
 
 Signs of Inherited Syphilis (Fig. 143), such as characteristic 
 physiognomy, peculiar conformation of the skull (square fore- 
 head, prominent frontal eminences, depressed bridge of nose), 
 radiating scars at angles of mouth, scars in the mouth and 
 pharynx, ozsena, enlarged cervical lymphatic glands, nodes on 
 the bones, and more or less impairment of hearing. The 'per- 
 manent teeth are ill-developed, their angles rounded off, and 
 there is often a crescentic notch in the free margin; these 
 changes are especially marked in the upper central incisor 
 teeth (Hutchinsonian teeth, Fig. 143). 
 
 Treatment. — Local: Atropine^ dionine (5 to 10 per cent.), 
 protection from light by smoked coquilles or by a shade, hot 
 compresses. When the cornea begins to clear, we employ 
 mild stimulating ointments, such as yellow oxide of mercury, 
 often combined with gentle massage, or instil 10-per-cent. 
 dionine, or dust dionine powder upon the cornea. We must 
 be careful not to apply stimulating ointments too early. 
 
 Constitutional: Calomel, gr. /{q four times a day, or potassic 
 iodide, gr. v., combined with corrosive sublimate, gr. }io, t. i. d., 
 or inunctions of mercury, syrup of the iodide of iron or other 
 preparation of iodine, cod-liver oil, iron and quinine, and 
 attention to the general health. In the uncommon cases 
 occurring in adults, we prescribe iodide of potassium, with or 
 without mercury, by mouth or by injections. There is much 
 
NON-SUPPURATIVE KERATITIS 149 
 
 difference of opinion as to whether salvarsan is of Value in 
 interstitial keratitis; but it should be tried in severe cases. 
 
 Pannus (Vasculo-nebulous or Vascular Keratitis) has been 
 described in connection with trachoma (p. 116). 
 
 UNCOMMON FORMS OF NON-SXTPPUBATIVE 
 KERATITIS 
 
 Vesicular Keratitis and Bullous Keratitis are varieties which occur 
 in blind eyes with increased tension and in damaged eyes with opaque 
 and insensitive corneae; the distinguishing feature is the occurrence of 
 small, clear vesicles or large, transparent blebs, accompanied by marked 
 symptoms of irritation and tendency to recur. Vesicles are also seen 
 on the cornea in the course of acute febrile diseases, especially pneumonia 
 and influenza, accompanying similar manifestations elsewhere, in 
 herpes febrihs cornese (p. 140) and in the keratitis compUcating herpes 
 zoster ophthalmicus (p. 42). When occurring with herpes the treat- 
 ment of keratitis in general is indicated; the vesicles should be punc- 
 tured, and quinine or sodium sahcylate be given internally. 
 
 Superficial Punctate Keratitis complicates acute affections of the 
 respiratory tract and begins with the symptoms of acute conjunctivitis. 
 Numerous small gray spots appear in the superficial layers of the 
 cornea, beneath Bowman's membrane; these are accompanied by gray 
 radiating lines and by some general clouding. The disease resembles 
 herpes, but it is bilateral and there are no vesicles. It occurs in young 
 persons and lasts several months, after which there is complete ab- 
 sorption. Treatment comprises attention to the conjunctivitis and the 
 bronchial affection, the use of atropine, hot compresses, and later the 
 ointmenit of the yellow oxide of mercury. 
 
 Keratitis Profunda is a form of deep-seated inflammation of the 
 cornea occurring in adults, in which a gray, central opacity of the 
 cornea develops, accompanied by moderate irritative symptoms; it be- 
 comes entirely or almost perfectly absorbed in a few weeks, and re- 
 quires treatment similar to that of interstitial keratitis. 
 
 Sclerosing Keratitis is the name given to the corneal complication of 
 scleritis (p. 160). The portion of the cornea adjacent to the scleritic 
 nodule participates in the process, and a triangular opacity remains. 
 The symptoms and treatment correspond to those of scleritis. 
 
 Band-shaped Keratitis {Transverse Calcareous Film of the Cornea) 
 is a whitish or grayish band, which extends across the cornea opposite 
 the palpebral aperture, and often contains hme. It occurs usually in 
 old persons, and in eyes which have been seriously injured or lost by a 
 
150 DISEASES OF THE CORNEA 
 
 previous intraocular affection. In eyes which retain vision, the treat- 
 ment consists in gently scraping away the band and using solutions of 
 sodium carbonate (gr. i. to § i.). 
 
 A number of other forms of keratitis are described, but are of very 
 rare occurrence. 
 
 Punctate Keratitis (Descemetitis) is the name given to dot- 
 like deposits upon the posterior surface of the cornea formed 
 of exudation in inflammations of the uveal tract (iritis, cy- 
 clitis, iridocyclitis). The name refers to a symptom and not 
 to a disease. This condition is never the result of an inflam- 
 mation limited to the cornea. It usually shows upon the 
 lower portion of Descemet's membrane, the area being tri- 
 angular with the base at the margin and the apex near the 
 centre of the cornea (Fig. 162, Plate XI). These deposits 
 are usually absorbed. 
 
 PKOTK.XJSIONS OF THE CORNEA 
 
 These may be either (1) of inflammatory origin, including 
 (a) staphyloma and (b) keratectasia; or (2) of non-dnflxim- 
 matory origin, comprising (a) keratoconus and (b) kerato- 
 globus. 
 
 Staphyloma of the Cornea is a bulging cicatrix lined 
 by prolapsed iris. It is one of the sequelae of perforation of 
 corneal ulcer (Fig. 144) . It may be total, when it replaces the 
 entire cornea, or partial, when it occupies only a portion of 
 this area. In shape it may be globular, conical, or lobulated. 
 Its color is whitish with bluish areas representing spots where 
 pigment shows through the thin cicatrix; it may be all white 
 or all bluish. Some blood-vessels are frequently seen on the 
 surface. It varies in size, being small in some cases and so 
 large in others that the lids cannot close. 
 
 Symptoms. — Besides the objective signs just mentioned, 
 there are changes in the eyeball, in the staphyloma, and in 
 the lids. There is almost always increased tension, often due 
 to seclusion of the pupil. This condition causes pain, pro- 
 duces changes in the interior of the eye which lead to' blind- 
 
STAPHYLOMA OF THE CORNEA 151 
 
 7iess, results in an increase in the size of the bulging, and is 
 responsible for staphyloma of the sclera. The conjunctiva 
 becomes the seat of inflammation from mechanical irritation. 
 The summit of the protrusion becomes dry and ulcerated, 
 and there is frequently rupture followed by closure of the 
 opening; this process may 
 be repeated a number of 
 times, until the eye is lost 
 and a shrunken globe re- 
 mains. 
 
 Even before these secon- 
 dary changes have taken 
 place, there is considerable 
 deformity, and sight is very 
 much reduced. In total 
 staphyloma there will be 
 
 merely perception of light ; fig. 144.— staphyloma of the Comea. 
 in the partial form the 
 
 amount of sight will depend upon the condition of the cornea 
 which is preserved, the position of the pupil, and the extent 
 to which the curvature of the cornea has become altered. 
 
 Treatment. — In ■partial staphyloma, an iridectomy should be 
 performed (p. 211) for the purpose of reducing tension, flat- 
 tening the protrusion and preventing its increase, and to serve 
 for optical purposes. We select the part of the iris corre- 
 sponding to the most clear portion of the cornea. If there is 
 no anterior chamber and the iris lies against the posterior 
 surface of the cornea, this operation is impossible. In such 
 cases, we may incise, or excise, a portion and unite with su- 
 tures, followed by a pressure bandage for a considerable period 
 of time. 
 
 In toted staphyloma, we resort to incision, abscission, or 
 enucleation. Abscission is performed by cutting off the pro- 
 trusion with knife and scissors, removing the lens, and bring- 
 ing together the edges of the corneal gap with sutures drawn 
 through corneal tissue, or better, through the conjunctiva 
 
152 
 
 DISEASES OF THE CORNEA 
 
 which has previously been freed around the limbus. Enu- 
 cleation, or one of its substitutes, is indicated in certain cases 
 in which the staphyloma is very large, painful, or the source 
 of danger to the other eye. 
 
 Keratectasia is a protrusion following inflammation of the 
 cornea without perforation; the bulging portion is opaque. 
 It may follow thinning from an ulcer which has not perfo- 
 rated or it may be due to softening of the cornea after pannus 
 and interstitial keratitis. There is always marked reduction 
 
 of vision. When fully developed, 
 treatment is of no avail. 
 
 Keratoconus or Conical 
 Cornea. — A non-inflammatorj^ 
 conical ^protrusion of the centre of 
 the cornea (Fig. 145), due to a 
 gradual atrophic thinning, in conse- 
 quence of which the cornea is 
 unable to resist the normal in- 
 traocular pressure. The condi- 
 tion is of infrequent occurrence, 
 usually bilateral, and begins to develop in young adults. It 
 is easily seen when well marked by looking at 
 the eye from the side; when less developed, it is 
 recognized by the shadow-test, by distortion of 
 the picture of the fundus with the ophthalmo- 
 scope, and by the alteration in shape of the im- 
 age when Placido's disc (Fig. 6) is used. The 
 condition tends to progress for many years be- 
 fore it comes to a standstill. It sometimes 
 presents a slight opacity at its apex; it never 
 ulcerates. Conical cornea causes myopia and 
 astigmatism and seriously interferes ivith sight, 
 even after the best possible correction with glasses. 
 Treatment consists in providing concave spherocylmders, re- 
 peated paracentesis followed by the long-continued applica- 
 tion of a pressure bandage, pilocarpine or eserine to diminish 
 
 Fig. 145. — Keratoconus. 
 
 Fig. 146.— Cor- 
 neal Electrode 
 for Keratoco- 
 nus. 
 
KERATOCONUS 
 
 153 
 
 tension, and abscission or cauterization of the apex of the cone 
 to cause flattening by subsequent cicatrization. 
 
 Cauterization is used most frequently and is moderately 
 successful; it is generally followed by an iridectomy for the 
 purpose of bringing the pupil opposite clear cornea. The 
 electrode used for this operation (Fig. 146) has a spherical 
 tip with which the apex of the cone is cauterized as deeply 
 as Descemet's membrane, or even with perforation. 
 
 Keratoglobus is a globular protrusion and enlargement of 
 the cornea which, although occasionally met with under other 
 circumstances, is usually one of the manifestations of con- 
 genital glaucoma and is described under this title (p. 218). 
 
 OPACITIES OF THE CORNEA 
 
 This term refers to a lack of transparency of the cornea 
 resulting from inflammation, ulceration, or injury. Accord- 
 ing to density, the corneal opacity is called nebula (Fig. 147), 
 when faint and cloud-like, often overlooked until examined 
 by oblique illumination; macula (Fig. 148), when more pro- 
 nounced and appreciable as a gray spot in daylight; leucoma 
 (Fig. 149), when dense and white. When the iris is attached 
 to the scar tissue, the condition is spoken of as adherent leu- 
 coma (Fig. 137, Plate X). 
 
 Opacities of the cornea interfere with perfect vision when 
 they involve or encroach upon the pupillary area, the degree 
 
 Fig. 147.— Corneal Nebula. Fig. 148.— Corneal Macula. Fig. 149. — Corneal Leucoma 
 
 depending upon their density. Even slight opacities cause 
 considerable visual disturbance on account of the resulting dif- 
 fusion of light. Denser opacities cause disfigurement. 
 
154 DISEASES OF THE CORNEA 
 
 Treatment. — Various measures are used to reduce the den- 
 sity of corneal opacities, or, if faint, to cause their disappear- 
 ance. These are of value only when the opacity is recent (less 
 than one year); they act most successfully in children and 
 when the change is superficial. Most commonly the ointment 
 of the yellow oxide of mercury is placed in the conjunctival 
 
 sac, after which the cornea is mas- 
 saged for a few minutes, and then 
 hot compresses are applied. Dio- 
 
 FiG. 150. — Tyson Tattooing- . , i ■• ■ • i-i i i x- 
 
 Needles. nine, thiosmamm, diluted tinc- 
 
 ture of opium, and other irri- 
 tants are used for this purpose. 
 FIG. i5i.-Grooved Tattooing- Qalvanism has givcu good re- 
 sults. Transplantation of the 
 cornea usually fails to give any but temporary improvement. 
 When such measures are unsuccessful, and the leucoma 
 entirely occludes the pupillary area, iridectomy for artificial 
 pupil (p. 215) may be performed, the coloboma being made 
 opposite a clear part of the cornea. 
 
 To remove the disfigurement in cases of leucoma, tattooing 
 is often resorted to. The eye is anaesthetized, and the leu- 
 coma covered with a thick paste of India ink; the pigment is 
 then introduced obliquely into the corneal substance, either 
 by means of an instrument consisting of a row or bundle of 
 roimd needles (Fig. 150) or with a grooved needle (Fig. 151). 
 The color fades in the course of a few years and then the 
 operation may be repeated. When the opacity covers only a 
 part of the pupillary area, tattooing is useful in preventing 
 the diffusion of light which is so annoying to the patient. 
 The operation is contraindicated when the cornea is very thin 
 or when likely to increase intraocular disease by irritation. 
 
 INJUKIES OF THE CORNEA 
 
 These comprise foreign bodies, burns, and wounds. 
 Foreign Bodies, consisting of iron, coal, ashes, dust, etc., 
 frequently adhere or become embedded in the cornea, causing 
 
FOREIGN BODIES IN THE CORNEA 
 
 155 
 
 much pain, lacrymation, and photophobia. When the foreign 
 body is small, it may be difficult to detect, unless we make 
 use of oblique illumination. The mischief which a foreign 
 body provokes depends upon the depth to which it penetrates 
 and whether or not it is in- 
 fected. If present for a 
 number of days, a sur- 
 rounding area of infiltration 
 appears, resulting in a small 
 ulcer, and in this mamier 
 the foreign body may be- 
 come dislodged; if it con- 
 sists of iron or steel, this 
 ring will become stained by 
 rust. Foreign bodies are 
 sometimes the cause of ul- 
 cers of the cornea. 
 
 To Remove a Foreign 
 Body. — The eye is holocain- 
 ized; the patient is seated 
 facing a good light with the 
 
 surgeon standing behind and supporting the head; the lids 
 are separated and the eyeball is steadied by the fingers of the 
 left hand; the index finger is applied to the margin of the 
 upper lid and the middle finger to the lower lid, and the two 
 fingers are separated, at the same time gently pressing back- 
 ward (Fig. 152). If the patient is seated in a chair provided 
 with a suitable head-rest, the surgeon may stand in front; 
 under such circumstances, the index finger is applied to the 
 lower lid and the middle finger to the upper (Fig. 153). 
 
 The instruments used are either the blunt spud, the gouge, 
 or the foreign-body needle (Figs. 154-156); these should be 
 sterilized before use. 
 
 When the foreign body is superficial, the blunt spud will 
 answer; very often the particle can be removed with a little 
 absorbent cotton wound around the end of the spud. When 
 
 Fig. 1j2. — Method of Removing a Foreign 
 Body from the Cornea (Surgeon Standing 
 Dehi..d the Patient). 
 
156 
 
 DISEASES OF THE CORNEA 
 
 it has penetrated into tlie corneal substance, it must be picked 
 or dug out witli the gouge, or the needle; in such cases, the 
 instrument is passed behind the foreign body. The wound 
 
 which results must be kept 
 clean by frequent irrigation 
 with solution of boric acid; 
 frequently homatropine and a 
 protective bandage are indi- 
 cated. If a ring of rust is 
 present, this also should be 
 removed. Care must be 
 taken to inflict as little in- 
 jury as possible, and when 
 the foreign body is deep, 7wt 
 to perforate the cornea. If it 
 has penetrated deeply into 
 the cornea, a keratome (Fig. 
 193) should first be passed 
 through the cornea and be- 
 hind the foreign bodj^, so 
 that the latter will not be pushed into the anterior chamber 
 during efforts at removal. 
 
 Bums of the cornea are treated like similar conditions of 
 the conjunctiva (p. 132). 
 
 Wounds may be non-pene- 
 penetrating. Non- 
 wounds are most 
 abrasions due to 
 scratches with the finger nail, 
 twig of a tree, or the like. Such 
 injuries, though very painful, 
 heal readily unless infected; 
 they should be kept clean by fre- 
 quent irrigation with solution of boric acid; a bandage may 
 be indicated, and sometimes atropine or homatropine. 
 Perforating Wounds are more serious owing to the danger 
 
 Fig. 153. — Method of Removing a For- 
 eign Body from the Cornea (Surgeon 
 Standing in Front of tbe Patient) . 
 
 trating or 
 penetrating 
 commonly 
 
 Fig. 154. — Foreign-Body Spud. 
 
 Fig. 155. — Foreign-Body Gouge. 
 
 <5= 
 
 c 
 
 Fig. 156. — Foreign-Body Needle. 
 
WOUNDS OF THE CORNEA 157 
 
 of prolapse of the iris and injury to the deeper parts. They 
 should be treated by thorough cleansing, atropine or eserine 
 according as they are central or peripheral, and a pressure 
 bandage. An attempt should be made to replace the iris, if 
 prolapsed; if this is unsuccessful, as is usually the case, the 
 prolapsed portion should be excised. It may be advisable to 
 cover the corneal wound with a conjunctival flap. If exten- 
 sive, the edges may be united with fine silk sutures. In very 
 severe wounds of the cornea involving deeper parts the ques- 
 tion of enucleation must be considered. 
 
CHAPTER IX 
 
 DISEASES OF THE SCLERA 
 
 Anatomy. — The sclerotic coat (sclera) is the tunic which with the cor- 
 nea forms the external fibrous layer of the eyeball; it is strong, opaque, 
 and inelastic, and serves to maintain the form of the globe. Its thick- 
 ness is about 1 mm., but varies at different points. Its structure resem- 
 bles that of the cornea, being composed of bundles of connective tissue 
 with some elastic fibres, disposed in both longitudinal and transverse 
 layers, between which are a few flat cells; these parts are, however, 
 much less regularly arranged than in the cornea. Anteriorly, the 
 structure of the solera is continuous with that of the cornea. In the 
 child, the sclera often has a bluish-white color, owing to its being 
 thinner and allowing the dark pigment of the choroid to show through. 
 The sclera is pierced about 2.5 mm. internal to the posterior pole of the 
 eye by the optic nerve; here it has blended with it the external fibrous 
 sheath of the nerve. The part through which the nerve passes is known 
 as the lamina cribrosa. 
 
 The outer surface of the sclera is white and smooth, covered by 
 Tenon's capsule and the conjunctiva, to which it is joined by loose con- 
 nective tissue {episcleral); in front, it presents the insertions of the ex- 
 trinsic muscles of the eyeball. Its inner surface is brown and rough, 
 being covered by deHcate, pigmented connective tissue, which is united 
 to the choroid by filaments traversing the lymph space existing between 
 the sclera and choroid; where it is pierced by vessels and nerves, a 
 communication between the capsule of Tenon and the suprachoroidea is 
 estabUshed. The points of emergence of the anterior ciliary veins are 
 often marked by small brown dots; and the anterior portion of the sclera 
 sometimes presents slate-colored or violet spots of pigmentation, es- 
 pecially in negroes. Though traversed by many blood-vessels, the 
 sclera itself has a very scant vascular supply; but the episcleral tissue 
 contains numerous vessels 
 
 Affections of the Sclera include superficial inflammation 
 (episcleritis), deep inflammation (scleritis), staphyloma, and 
 injuries. 
 
 Inflammation of the Sclera (Scleritis) may be either super- 
 ficial or deep. The superficial form, called episcleritis, is lim- 
 
 158 
 
INFLAMMATION OF THE SCLERA 159 
 
 ited to the tissues superficial to the sclera and is relatively 
 harmless. The deep form, known as sderitis, involves the 
 sclera itself and extends to subjacent and contiguous parts, 
 causing serious consequences. There is often an absence of 
 a sharp line of division between the two forms. 
 
 EPISCLERITIS 
 
 An inflammation of the episcleral tissue. 
 
 Symptoms. — There are usually slight discomfort, lacryma- 
 tion, and pain, but occasionally there are more marked symp- 
 toms of irritation. A slightly raised patch of red or purple 
 color is seen in the ciliary region (Fig. 126, Plate IX), usually 
 on the temporal side, presenting both conjunctival and epi- 
 scleral congestion, and more or less tender on pressure. After 
 a few weeks, the node will disappear; but others are apt to 
 take its place; in this way the process may encircle the cornea. 
 Owing to this tendency to relapses, the disease often lasts 
 many months. Sometimes some discoloration of the sclera 
 remains ; occasionally the cornea and iris are implicated. The 
 disease may resemble a marked case of phlyctenular conjunc- 
 tivitis; it may merge gradually into sderitis. 
 
 Etiology. — It is usually observed in adults, especially in 
 women; often in rheumatic and gouty individuals. Syphilis, 
 tuberculosis, and menstrual disorders are predisposing 
 factors. 
 
 Treatment should be of a sedative nature: Warm com- 
 presses and warm boric-acid solution; if the cornea or iris is 
 implicated, atropine. The occasional instillation of 1-per- 
 cent, solution of holocain in 10,000 adrenalin will relieve the 
 discomfort. Dionine may prove useful. The ointment of 
 the yellow oxide of mercury (1 per cent.), applied with gentle 
 massage, and the subconjunctival injection of physiological 
 salt solution are sometimes of value, especially when the dis- 
 ease shows a tendency to become obstinate. Superficial cau- 
 terization with the galvano-cautery may be useful in chronic 
 cases. With or without a rheumatic or gouty history, sodium 
 
160 DISEASES OF THE SCLERA 
 
 salicylate and aspirin are useful. Iodide of potassium may be 
 tried, also diaphoresis. Hypodermic injections of tuberculin 
 are often effective in patients who show a local reaction to 
 the diagnostic tuberculin test (p. 406). 
 
 Transient Periodic Episcleritis is a variety of episcleritis 
 which appears in sudden attacks lasting several days, reap- 
 pears at intervals of several weeks or months, and may recur 
 for years. It is seen in gouty and rheumatic adults. The 
 treatment is that recommended for episcleritis. 
 
 SCLEBITIS 
 
 An inflammation of the sclera, in which the symptoms are 
 acute, the course is prolonged, and the consequences are seri- 
 ous. In this disease the sclera itself is involved in the inflam- 
 matory process; it becomes softened, thinned, and staphyloma 
 results. Both eyes are frequently involved. Relapses are 
 very common. 
 
 Symptoms. — Pain, usually severe, and frequently radiating 
 to neighboring regions, tenderness over ciliary region, lacry- 
 mation, and photophobia. The tension of the eyebaU is fre- 
 quently increased; secondary glaucoma often ensues. 
 
 There are well-marked dark-red or violet patches adjacent to 
 the cornea, often extending to the equator, and frequently 
 surrounding the limbus; in some cases, small, white, hard 
 nodules develop in the inflamed area beneath the conjunctiva. 
 After subsidence of the inflammation the seat of the affected 
 areas is often marked by pale-violet discoloration. 
 
 Complications. — The cornea is frequently implicated and 
 sclerosing keratitis (p. 149) follows. Often there are iritis, 
 cyclitis, choroiditis, opacities of the vitreous, and secondary 
 glaucoma; the combination of such complications is known 
 as anterior uveitis. As a result of these changes, vision is 
 often seriously interfered with and sometimes lost. The 
 thinning of the sclera results in staphyloma of the anterior 
 portion of the globe and causes myopia. 
 
 Etiology. — The disease is most common in young adults, and 
 
SCLERITIS 
 
 161 
 
 especially in women. Rheimiaiism and gout, syphilis, tuber- 
 culosis, and disorders of menstruation are predisposing fac- 
 tors. Exposure to cold is sometimes the exciting cause. 
 
 Treatment comprises the measures advocated in episcleritis, 
 energetically applied. In addition, the complicating kera- 
 titis and iritis require appropriate treatment. Tuberculin 
 injections are effective in some cases. After the acute symp- 
 toms have subsided, an iridectomy is sometimes advisable: 
 for diminishing glaucomatous tension, preventing an in- 
 crease in the staphyloma, and establishing an artificial pupil. 
 
 STAPHYLOMA OF THE SCLERA 
 
 A thinning and bulging of the sclerotic which, when partial, 
 occurs either at the anterior portion, the equator, or the pos- 
 terior portion of the eyeball; when total it involves the entire 
 globe (congenital glaucoma, p. 218). 
 
 Anterior and Equatorial Staphylomata are caused by dis- 
 turbed relation between the re- 
 sistance of the sclera and the in- 
 traocular tension; such conditions 
 are found after chronic glaucoma, 
 iridocychtis, ectasia of the cornea, 
 scleritis, and injuries of the sclera. 
 They present a bluish-gray bulg- 
 ing which may be limited or may 
 extend all around the cornea (Fig. 
 157). This bulging shows a ten- 
 dency to increase; occasionally it 
 bursts. Iridectomy , if feasible, is 
 
 the only treatment, and is done for the purpose of arrest- 
 ing the process. In some cases, when the enlarged eye- 
 ball causes much discomfort and is sightless, enucleation or 
 evisceration is advisable. 
 
 Posterior Staphyloma, situated at the posterior pole of the 
 eyeball, is of common occurrence and is generally associated 
 with myopia and choroiditis (p. 185). It is seen with the 
 
 Fig. 157. — Anterior Staphylo- 
 mata of the Sclera. 
 
162 DISEASES OF THE SCLERA 
 
 ophthalmoscope, presenting a white crescentic or irregular 
 patch which embraces the temporal side of the optic disc (Fig. 
 174, Plate XIII, and Fig. 177, Plate XIV). 
 
 INJURIES OF THE SCLERA 
 
 The important injuries include perforating wounds and 
 rupture; these are serious on account of the danger of injury 
 to the inner layers, escape of the contents of the eyeball, and 
 infection of the interior. 
 
 Small, clean, perforating wounds often heal without reac- 
 tion, if there is no infection at the time of the injury, 
 and require merely cleansing, conjunctival suture, and a 
 bandage. 
 
 Large, gaping wounds frequently allow escape of the vit- 
 reous; in addition there will be hemorrhage in the vitreous, 
 diminished tension, and some of the underlying tissues (cho- 
 roid, ciliary body, or iris) varying with the position, will be 
 found in the wound. Such wounds should be cleansed, the 
 prolapsed parts returned when not too seriously injured, the 
 opening closed by sutures in the sclera (being careful to avoid 
 the choroid) or preferably through the conjunctiva, the 
 patient kept absolutely quiet, and the eye bandaged. 
 
 Sometimes such wounds fail to excite much inflammatory 
 reaction and may heal readily, even though there is incar- 
 ceration of the prolapsed parts in the scar. But frequently 
 they give rise to panophthalmitis with ultimate phthisis bulbi, 
 or to plastic iridocyclitis with loss of sight. When the wound 
 involves the ciliary body, iridocyclitis is apt to be set up, and 
 the injury becomes more dangerous on account of the liabil- 
 ity of such wounds to excite sympathetic ophthalmitis. 
 
 Ruptures of the sclera are produced by blows and blunt in- 
 struments; they usually occur near the corneal margin, gen- 
 erally above and internally. The conjunctiva may not be 
 broken. The prognosis is unfavorable and most of such eyes 
 are lost, since, with force sufficient to rupture the sclera, there 
 are usually serious lesions in the interior of the eye, such as 
 
INJURIES OF THE SCLERA 163 
 
 separation of the iris, dislocation of the lens, detachment of 
 the retina, and hemorrhage into the vitreous. 
 
 When injuries of the sclerotic are very extensive and cause 
 considerable loss of contents of the eyeball, and when we be- 
 lieve that useful sight cannot be hoped for, the eyeball should 
 be removed at once. This becomes still more urgent when the 
 wound involves the dangerous zone, the ciliary region. 
 
 The presence of a foreign body in the eye is a serious com- 
 plication. The attempt should be made to extract the 
 particle, as described on p. 224. 
 
CHAPTER X 
 
 DISEASES OF THE IRIS 
 
 Anatomy and Physiology. — The second or vascular coat of the eye 
 {uvea or uveal tract) Ues immediately beneath the sclera; it provides for 
 the nourishment of the eyeball, and it is formed of three parts, which 
 from before backward are known as the iris, the ciliary body, and the 
 choroid. These three portions are so intimately associated that when 
 one part becomes diseased, the others frequently participate. 
 
 The Iris is a colored membrane, circular in form, hanging behind the 
 cornea immediately in front of the lens, and perforated in its centre by 
 an aperture of variable size, the pupil; it serves to regulate the amount 
 of Ught admitted to the interior of the eye, and cuts off the marginal 
 rays which would interfere with the sharpness of the retinal image. 
 Its peripheral border springs from the head of the ciUary body and the 
 ligamentum pectinatum. Its free inner edge, the boundary of the 
 pupU, Ues upon the anterior capsule of the lens when the pupil is con- 
 tracted or moderately dilated; with maximum dilatation it hangs free 
 in the anterior chamber. The iris separates the anterior from the 
 posterior chamber of the eyeball. Its anterior surface presents great 
 variation in color in different eyes, and is marked by radially directed, 
 wavy lines, converging toward the circle of irregular elevations and small 
 depressions (crypts) situated near the pupil; other finer hnes are seen 
 extending from this ring to the pupil; this appearance is produced by the 
 subjacent blood-vessels. 
 
 In structure, the iris consists of a delicate, spongy connective-tissue 
 stroma, containing branched pigmented cells, muscular fibres, and an 
 abundance of vessels and nerves. It is covered anteriorly by endothe- 
 lium except at the crypts, where the stroma of the blood-vessel layer 
 communicates directly with the anterior chamber — an arrangement 
 which permits rapid exchange of aqueous from iris to anterior chamber 
 and vice versa; posteriorly it presents the posterior limiting membrane 
 and the retinal pigment layers. 
 
 The color of the iris depends partly upon the pigment in the stroma 
 cells, which is variable, and partly on that in the cells of the retinal 
 layers, which is constant. 
 
 The muscle tissue consists of (1) the sphincter pupillcB, a narrow 
 band, about one millimeter wide, situated close to and encircUng the 
 pupil posteriorly, and supplied by the third nerve, and (2) the dilatator 
 pupillcB, an epithelial muscle, consisting of long spindle-shaped cells 
 arranged meridionaUy, which extends along the posterior surface of the 
 blood-vessel layer from the sphincter pupillae to the root of the iris and is 
 suppUed by the sympathetic, 
 
 164 
 
ANATOMY OF THE IRIS 165 
 
 The posterior surface of the iris is covered by two strata of pigmented 
 cells, the uveal layer, which extends to the free border around which 
 it turns a httle, forming the black fringe of the pupillary margin. 
 
 The vessels of the iris come from the two branches of the ophthalmic 
 known as the long posterior cihaiy arteries; each artery divides into an 
 upper and a lower branch; these anastomose _ with the corresponding 
 vessels of the opposite side and with the anterior cihary, and form a 
 vascular ring just behind the attached margin of the iris, the greater 
 vascular circle of the iris. This gives off branches to the ciliary body 
 and iris; the iris branches converge toward the pupil and here form by 
 anastomosis a smaller vascular circle, the lesser vascular circle of the 
 iris. The veins of the iris follow the arrangement of arteries just de- 
 scribed; in addition they communicate with the canal of Schlemm; 
 they chiefly pass backward to the vense vorticosse. 
 
 The nerves are given off from the plexus in the ciliary body, and are 
 derived from the third, the nasal branch of the ophthalmic, and the 
 sympathetic. 
 
 Pupillary Membrane. — In the fcetus the pupil is closed by a thin, 
 transparent dehcate membrane — the pupillary membrane. The mem- 
 brane and its vessels are gradually absorbed in the seventh or eighth 
 month of foetal hfe. A few shreds may remain at birth; occasionally 
 part or all of the membrane persists (persistent pupillary membrane). 
 
 IRITIS 
 
 Inflammation of the iris is so frequently associated with 
 inflammation of the cihary body (cychtis), that most cases 
 which are designated iritis are really examples of irido- 
 cyclitis. It will be convenient, however, to describe the two 
 affections separately. 
 
 Varieties: Iritis may be divided into primary, when de- 
 veloping in the iris itself, and secondary, when the inflamma- 
 tion spreads from neighboring parts, such as the cornea. 
 
 According to its course, it may be acute or chronic. 
 
 Depending upon its etiology, it may be classified as (1) 
 Syphilitic, (2) Rheumatic, (3) Gouty, (4) Gonorrhceal, (5) 
 from Septic Infection, (6) Diabetic, (7) Scrofulous, (8) Tuber- 
 culous, (9) Traumatic, (10) S3Tnpathetic, and (11) Idiopathic. 
 
 Iritis has also been divided according to the nature of the 
 products of inflammation into plastic, serous, spongy, puru- 
 lent, nodular, etc.; but this classification is imsatisfactory 
 because one type merges into the other. 
 
 It will be advisable to consider Iritis in General, and then 
 
166 DISEASES OF THE IRIS 
 
 to mention the peculiarities of the different forms which have 
 
 been named according to their etiolog3^ 
 
 Objective Symptoms (Figs. 160, 161, 162, Plate XI).— The 
 
 iris looks altered. It appears swollen, dull, loses its lustre, its 
 
 markings become indis- 
 tinct, its color changes and 
 becomes greenish in blue 
 or gray irides, and muddj^ 
 in darker varieties. These 
 changes are due to con- 
 gestion of the iris and ex- 
 udation of cells and fibrin 
 into its substance; also to 
 
 Fig. 158. — Posterior Synechiae Causing Ir- , .. * _l j i , 
 
 regular Pupil in Iritis. exutlatiou into the ante- 
 
 rior chamber. 
 
 The jiupil is contracted, grayish, sluggish in action, and irreg- 
 ular (Fig. 158); the last peculiarity is due to adhesions be- 
 tween the posterior surface of the iris and the anterior capsule 
 of the lens {^posterior synechice), best seen after the instillation 
 of atropine. 
 
 The contents of the aqueous chamber show changes; there 
 is frequently turbidity; there may be more or less dust-like 
 deposit on Descemet's membrane (so-called keratitis punc- 
 tata), which often involves the lower part (Fig. 162, Plate XI) 
 or may give a cloudj' appearance to the entire cornea. In 
 this exudation there may be pus which then gravitates to the 
 bottom (hypopyon) or fibrin, which coagulates into a grayish 
 mass (spongy iritis), or blood (hyphcema) . The anterior cham- 
 ber may be deeper than normal. The tension of the ej^eball, 
 though usually normal, may be increased or diminished. 
 
 The anterior capsule of the lens may present evidences of 
 exudation, and also small spots of uveal pigment where poste- 
 rior synechia have been torn away. 
 
 There is always marked circumcorneal injection, and 
 with this pink zone there may be more or less conjunctival 
 congestion. 
 
 Subjective S5miptoms consist of pain, photophobia, laa-ynia- 
 tion, interference with vision, and sometimes general malaise. 
 

 PLATE 
 
 XI 
 
 
 
 
 ^^ET'^'' 
 
 
 '"^w--: i'^'i^^^^mjmi 
 
 , ' '' 
 
 WB / ^ 
 
 tft^^Vk 
 
 
 ^^iHv 
 
 1 
 
 
 !r 'v 
 
 
 
 
 t 
 
 ■B 
 
 
 
 :_ ..:J 
 
 KiG. 159.— Normal Kye (for f'omparisou). 
 
 Vm. ItU). -Iriti; 
 
 Flo 11)1 - — ^.^llhlllrlc Inti'^ 
 
 Pk. IhJ — -Serous Iridoi > ( litis 
 
 Fig. 163. — Panophthalmitis. 
 
 Fig. 164. — Panophthalmitis 
 
 c-.^r- icQ-ie^ — ujf.o iririn/vwr.ritis. Panophthalmitis. 
 
DIAGNOSIS OF IRITIS 
 
 167 
 
 The pain is often severe, referred to the eyeball itself and 
 radiating to the forehead and temple, and worse at night. 
 It is sometimes accompanied by tenderness of the eyeball, a 
 symptom pointing to involvement of the ciliary body. 
 
 The diminution in the acuteness of vision depends upon 
 cloudiness of the anterior chamber, deposits in the pupil and 
 upon Descemet^s membrane, and upon transient myopia and 
 astigmatism. When very marked, it indicates extension of 
 the inflammation to the deeper parts. 
 
 Differential Diagnosis. — Iritis is most frequently mistaken 
 for acute catarrhal conjunctivitis. Sometimes acute glaucoma 
 is mistaken for iritis. The differential points are given in the 
 following tables : 
 
 Acute Iritis. 
 
 1. Iris swollen, dull, and 
 discolored. 
 
 2. Pupil small, gray, 
 sluggish, irregular after use 
 of atropine. 
 
 3. Anterior chamber of 
 normal depth (deeper in 
 serous form) and presents 
 exudation. 
 
 4. Cornea transparent 
 (may present deposits on 
 posterior surface) and sen- 
 sitive. 
 
 5. Ciliary (circumeor- 
 neal) injection; pink zone 
 of fine vessels surrounding 
 cornea and fading toward 
 fornix. 
 
 6. Conjunctiva usually 
 transparent. 
 
 7. Laerymation but no 
 discharge. 
 
 8. Tension usually nor- 
 mal (occasionally altered). 
 
 9. Some ciliary tender- 
 ness. 
 
 10. Pain radiating to fore- 
 head and temple, worse at 
 night. 
 
 11. Dimness of vision. 
 
 Acute Conjunctiuitis. 
 1. No change in iris. 
 
 2. Pupil normal. 
 
 mal. 
 
 3. Anterior chamber nor- 
 
 4. Cornea transparent- 
 
 5. Conjunctival injec- 
 tion, coarse meshes, most 
 pronounced in fornix and 
 fading toward the cornea. 
 
 6. Conjunctiva reddened 
 and opaque. 
 
 Y. Mudous or muco- 
 purulent discharge. 
 
 8. Tension normal. 
 
 9. No ciliary tenderness. 
 
 10. Discomfort, hot gjitty 
 feeling, but no real pain. 
 
 11. No interference with 
 vision, except blurring 
 caused by the discharge 
 smeared over the surface of 
 the cornea. 
 
 Acute Glaucoma. 
 
 1. Iris congested, dis- 
 colored, dull, periphery 
 pushed forward. 
 
 2. Pupil dilated, oval, 
 immobile. 
 
 3. Anterior chamber 
 shallow and aqueous some- 
 times turbid. 
 
 4. Cornea steamy and 
 insensitive. 
 
 5. Ciliary and episcleral 
 injection (also conjunc- 
 tival congestion). 
 
 6. Conjunctiva congest- 
 ed and chemotic. 
 
 7. Laerymation but no 
 discharge. 
 
 S. Tension increased. 
 
 9. Ciliary tenderness. 
 
 10. Severe pain in and 
 about eye, with headache. 
 
 11. Marked dimness of 
 
 Course. — Iritis may be acute and run its course in several 
 weeks; or it may be chronic and last a number of months. A 
 great many cases terminate favorably, especially when sub- 
 jected to proper treatment early; the exudation becomes 
 absorbed, and the iris returns to a normal condition with no 
 
168 
 
 DISEASES OF THE IRIS 
 
 evidences or mere traces of former inflammation. On the 
 other hand, serious complications and disastrous sequelae may 
 arise; hence the prognosis should be guarded. Chronic cases 
 present very mild inflammatory symptoms, or the latter may 
 be entirely absent. Certain forms of iritis have a tendency 
 to recur. Iritis may involve one or both eyes; when both eyes 
 are attacked, the second usually is affected a short time after 
 the first. 
 
 Complications. — The neighboring parts of the eye are some- 
 times involved in severe forms of iritis: conjunctiva, cornea, 
 
 Fig. 165. — Section of the 
 Anterior Portion of the 
 Eyeball showing the Iris 
 in its Normal Relations. 
 
 Fig. 166. — Section showing 
 Annular Posterior Syne- 
 chia (Exclusion of the 
 Pupil.) 
 
 Fig. 167. — Section showing 
 Total Posterior Synechia 
 and Occlusion of the Pu- 
 
 pa. 
 
 ciliary body, choroid, vitreous, optic nerve, and retina. As 
 already mentioned, the association of inflammation of the 
 ciliary body (cyclitis) with iritis (iridocyclitis) is so common, 
 that some authors describe the two conditions together and 
 regard pure iritis as rare. The following symptoms, occur- 
 ring in the course of an iritis, point to the existence of cyclitis: 
 Violent inflammatory symptoms, including sweUing of the 
 upper lid; marked diminution in vision when greater than 
 can be explained from visible opacities; tenderness in the 
 ciliary region; deposits upon the posterior surface of the 
 
IRITIS 169 
 
 cornea and in the pupillary area and extensive synechise, in- 
 dicating great exudation; increase or decrease of normal 
 tension. 
 
 Sequelae. — These are often posterior synechia and deposits 
 upon the anterior lens capsule; less frequently there are ex- 
 clusion of the pupil, occlusion of the pupil, atrophy of the 
 iris, opacities of the vitreous, deposits upon the posterior cap- 
 sule of the lens, and cataract. In exclusion (or seclusion) of 
 the pupil (annular posterior synechia), the iris is bound down 
 throughout its entire pupillary margin, the pupil remaining 
 clear (Fig. 166) ; this causes a loss of communication between 
 the anterior and the posterior chamber; the aqueous secreted 
 by the ciHary processes is hemmed in, the iris stretched (iris 
 bombe) and atrophied, glaucoma results, and, if unrelieved, 
 blindness follows; if the whole posterior surface of the iris 
 becomes adherent to the anterior capsule of the lens the con- 
 dition is known as total posterior synechia. Occlusion of the 
 pupil is a fining in of the pupillary space with opaque exudate 
 (Fig. 167). Exclusion and occlusion of the pupil often occrn- 
 together. 
 
 Etiology. — Primary iritis is frequently dependent upon 
 some constitutional disease: very often syphilis; quite fre- 
 quently rheumatism and gonorrhoea; less commonly the scrofu- 
 lous diathesis, tuberculosis, gout, acute infectious diseases and 
 diabetes. It may also be a local affection and then not in- 
 frequently be due to infection from diseased teeth, tonsils, 
 nasal sinuses or more remote parts; it may be traumatic or 
 sympathetic (from injiu-y to the other eye). Many cases are 
 called idiopathic, when we are ignorant of the cause. 
 
 Pathology. — Inflammation of the iris presents similar 
 changes to those occurring in other connective tissue, modi- 
 fied by the great vascularity of this membrane and the loose- 
 ness of its stroma. There are dilatation of the blood-vessels 
 and exudation of lymph, lymphocytes, and fibrin into the 
 stroma and anterior chamber. These products of inflamma- 
 tion may be completely absorbed, or may become organized 
 into connective tissue, forming adhesions and causing degen- 
 erative changes in the iris. 
 
170 
 
 DISEASES OF THE IRIS 
 
 Treatment. — (1) Atropine, (2) dionine, (3) leeches, (4) hot 
 fomentations, (5) rest, (6) protection from light, (7) sweating, 
 (8) treatment of etiological factor. 
 
 Atropine diminishes the congestion of 
 the iris, puts this part at rest, causes 
 'mydriasis, and thus prevents adhesions 
 and tends to break up those which have 
 already formed. Sufficient should be in- 
 stilled to keep the pupil widely dilated — 
 every 2 hours at first, and later 3 or 4 times 
 a day. When the inflammation is pro- 
 nounced, the pupil will not dilate read- 
 ily. The action of atropine is often 
 increased by the addition of cocaine. Oc- 
 casionally, symptoms of atropine poison- 
 ing (p. 401) occur, either local or constitu- 
 tional, necessitating the substitution of 
 some other mydriatic (duboisine, hyoscya- 
 mine, scopolamine, solution of the aqueous 
 extract of belladonna 1:8). Exceptionally 
 atropine causes an increase in pain arid 
 must be stopped or replaced by a miotic; 
 this action is apt to occur when there is increased tension, 
 sometimes due to complicating cyclitis. 
 
 Dionine (5 to 10 per cent.) acts favorably upon the pain 
 and other symptoms. 
 
 The abstraction of blood from the temple by means of 2 to 
 4 leeches or the artificial leech (Fig. 168) always has a favor- 
 able effect upon pain and other symptoms. 
 
 Moist, hot compresses for several hours each day diminish 
 the pain and the inflammation. It is only in traumatic iritis 
 that cold compresses may be of service for the first day or two. 
 Absolute rest in bed in the early stages, and protection from 
 light, by means of smoked coquilles or a shaded room, are 
 essential. 
 
 Other important indications are light diet, abstinence from 
 alcoholics, a brisk purge, sweating, and avoidance of all use of 
 the eyes for near work. 
 
 Fig. 168.— Artificial 
 Leech. 
 
TREATMENT OF IRITIS 171 
 
 Constitutional Treatment must meet the indications in the 
 different forms. In syphilitic iritis mercury is given, usually 
 by inunction, to the point of salivation; after acute symptoms 
 have subsided, mixed treatment (mercury and iodide of potas- 
 sium) ; an injection of salvarsan is followed by most gratifying 
 improvement. In certain apparently idiopathic forms, small 
 doses of mercury have a favorable effect. In rheumatic cases 
 we prescribe large doses of salicylate of sodium or aspirin; 
 these remedies also have a quieting effect upon the pain in 
 other forms. 
 
 Paracentesis is occasionally done for the relief of continued 
 high tension, and also in certain obstinate cases; iridectomy is 
 sometimes performed for the same reasons. As a rule, how- 
 ever, operative procedures are useful only after the inflam- 
 matory symptoms have subsided, for the purpose of remedy- 
 ing sequelae. 
 
 It remains to consider briefly the distinctive features of 
 certain varieties of iritis. 
 
 Clinical Varieties. — Syphilitic Iritis is the most common 
 form. It occurs in the secondary stage of acquired syphilis, 
 usually during the first year after infection; it is usually acute; 
 both eyes are attacked, the second soon after its fellow. In 
 some cases there are no characteristic symptoms distinguish- 
 ing this from other forms of iritis, though there are always 
 apt to be broad and thick synechise (plastic), and pain is often 
 insignificant. In other cases there are yellowish-red nodules 
 of the size of a pin's head or larger (Fig. 161, Plate XI), usu- 
 ally multiple, situated upon the pupillary or ciliary border 
 (iritis papulosa) . There is often accompanying disease of 
 the posterior portion of the eyeball (choroid, retina, and op- 
 tic nerve). If properly treated relapses are not common. 
 Infrequently, syphilitic iritis is seen in childhood as a result 
 of inherited syphilis, being then usually associated with in- 
 terstitial keratitis; rarely, the iris is the seat of a gumma in 
 the tertiary stage. 
 
 Rheumatic Iritis is usually acute; it is frequently unilateral, 
 though sometimes it attacks both eyes; it occurs especially in 
 adults; the exudation is usually- plastic with narrow adhe- 
 
172 DISEASES OE THE lEIS 
 
 sions; pain is pronounced; relapses are common. It is not 
 usually found with acute rheimiatism, being associated with 
 the more chronic manifestations of this diathesis. 
 
 Gouty Iritis is uncommon and resembles the rheumatic 
 form. 
 
 Gonorrhceal Iritis is much more common than is generally 
 supposed; many cases called rheumatic are really gonorrhceal. 
 It occurs after gonorrhoea, usually subsequent to an attack of 
 arthritis, and depends upon the influence of the gonococci or 
 their toxins in the circulation upon the iris. It resembles the 
 rheumatic form; the exudate is plastic, pain is pronounced, 
 and relapses common. Besides treatment applicable to all 
 forms of iritis and the use of salicylates and aspirin, injections 
 of gonococcic vaccine are indicated and often valuable. 
 
 Iritis from Septic Infection from the teeth (pyorrhoea and 
 alveolar abscess), tonsils, nose or nasal accessory sinuses is 
 not uncommon; an examination of these parts ought never to 
 be omitted when the etiology is in doubt. 
 
 Diabetic Iritis occurs sometimes in diabetes, is plastic in 
 character, chronic in course, and may be accompanied by 
 hemorrhage into the anterior chamber. 
 
 Scrofuliis Iritis is the name given to a form which occurs in 
 scrofulous children and young adults, resembling the iritis 
 due to inherited syphilis, and often presenting a mass of lar- 
 daceous exudate. 
 
 Tuberculous Iritis is a rather rare form which occurs in 
 children and young adults, either with or without tubercu- 
 losis of other parts. It appears under two forms: (1) the 
 miliary, in which small grayish-yellow nodules develop near 
 the pupillary or ciliary border, and (2) the conglomerate form 
 in which a single yellowish-gray mass is found in the ciliary 
 part of the iris; with these there will be more or less evidence 
 of plastic iritis. In mild cases, the tuberculous deposits may 
 be completely absorbed; in others the process leads to de- 
 struction of the eyeball. Treatment comprises the usual 
 management of iritis and tuberculosis, and injections of tuber- 
 culin; in unfavorable cases in which sight is lost, enucleation 
 is advisable to prevent extension of the tuberculous process. 
 
Fig. 169. — Iridodialysis. 
 
 INJURIES OF THE IRIS 173 
 
 Traumatic Iritis occurs as a result of accidental injury or 
 an operation wound; the course depends upon whether infec- 
 tion takes place. 
 
 Sympathetic Iritis is merely part of Sympathetic Ophthal- 
 mitis (p. 188). 
 
 Tumors of the Iris may be (1) inflammatory: a, syphilitic, 
 h, tuberculous, both of which have just been described; and 
 (2) new growths: cysts, mela- 
 noma, and sarcoma, all of 
 which are rare. 
 
 Injuries of the Iris may 
 be (1) non-perforating and 
 (2) perforating. 
 
 (1) Non-perforating inju- 
 ries (concussion, blows upon 
 the eyeball) may cause (a) 
 mydriasis (as a result of pa- 
 ralysis of the sphincter of the iris, iridoplegia), (b) a tear in 
 the pupillary margin, in both of these cases eserine being 
 indicated; (c) iridodialysis, a separation of the ciliary border 
 of the iris (Fig. 169), for which atropine is required. When 
 the iris is torn, either at the pupillary or the ciliary border, 
 there will be blood in the anterior chamber (hyphsema). 
 
 (2) Perforating injuries are usually complicated by wounds 
 of the lens and other parts of the eye. A perforating wound 
 of the eyeball may lacerate the iris or merely allow the latter 
 to project through a wound of the cornea or of the ciliary 
 region (prolapse). In cases of prolapse, the wound must be 
 irrigated with a mild cleansing lotion, such as boric acid or 
 weak bichloride; if seen early, within a few hours, and there 
 is no injury to iris and lens, the iris may be returned into the 
 anterior chamber, atropine or eserine used according to the 
 seat of the perforation, and a bandage applied. If there is 
 little hope of saving the prolapsed portion of the iris, it 
 should be excised, the cut edges carefully separated from the 
 wound by a spatula, atropine or eserine used according to the 
 seat of the injury, and the eye bandaged. 
 
174 DISEASES OF THE IRIS 
 
 K foreign body may pass through the cornea and lodge upon 
 the iris; in such a case, the particle should be removed by 
 forceps after a preliminary incision with the lance-shaped 
 knife at the lunbus; if composed of iron or steel it may be 
 drawn out with a magnet. If these efforts are unsuccessful, 
 the piece of iris upon which the foreign body lies should be 
 drawn through the wound and excised. 
 
 Operations upon the Iris. — Iridectomy is the most impor- 
 tant operation upon the iris. It is described with glaucoma 
 (p. 209), which forms its most frequent indication. 
 
 Iridotomy, the formation of an artificial pupil, is indicated 
 in cases in which, after loss of the lens following injury or 
 cataract operation, the pupil has been closed by inflammation 
 or been drawn toward the cicatrix. The iris-membrane is 
 cut transversely with a Graefe knife or a knife-needle; or with 
 special forceps-scissors introduced through a small corneal 
 incision; or a V-shaped incision may be made with a knife- 
 needle, apex superiorly, forming a flap which falls down 
 or is pushed down behind the lower part of the iris- 
 membrane. 
 
 THE PUPIL 
 
 The normal pupil is circular and regular in outline. It is 
 larger in the young than in advanced life. Its size should 
 equal that of its fellow; both should respond alike when one 
 is subjected to a change in intensity of illumination. The 
 movements of the pupil are contraction and dilatation. 
 
 The contracting fibres of the iris (sphincter pupillos) are 
 supplied by the third nerve. The dilating fibres (dilatator 
 pupilloe) are supplied by the sympathetic. Changes in the 
 size of the pupil also depend upon variations in the calibre of 
 its blood-vessels, which are also supplied by the sympathetic. 
 
 Contraction of the pupil is effected by stimulation of the 
 oculomotor nerve and by paralysis of the sympathetic. Dila- 
 tation follows paralysis of the third nerve or stimulation of 
 the sympathetic. 
 
 The oculomotor-nerve fibres are conveyed through the ciliary 
 ganglion and short ciliary nerves. The nucleus of origin of 
 the third nerve concerned in the movements of the iris is in 
 
THE PUPIL 
 
 175 
 
 the floor of the aqueduct of Sylvius, and can be divided into 
 three portions: (1) that giving rise to the sphincter fibres of 
 the iris, (2) accommodation (ciliary muscle), and (3) conver- 
 gence (internal rectus). The sympathetic or dilating fibres are 
 given off from the cilio-spinal centre of -the lower cervical 
 spinal cord. 
 
 The pupil contracts upon exposure to light, with accommo- 
 dation, and with convergence. The light contraction may 
 
 be direct or consensual. The 
 direct light reflex is obtained by 
 exposing one eye to increased 
 illumination and observing the 
 contraction of the pupil of 
 this eye. The consensual or 
 indirect light reflex is obtained 
 by throwing light into one eye 
 and observing the contraction 
 of the pupil of the other eye. 
 The direct and consensual re- 
 actions are practically equal. 
 The accommodation and con- 
 vergence reflex is obtained by 
 directing the patient to look 
 at an object held several 
 inches in front of the face in 
 the middle line; the pupils will 
 be seen to contract. These 
 three actions are associated. 
 
 The dilatation reflexes of the 
 pupil are seen upon shading 
 the eye (both direct and con- 
 sensual), and upon looking at a 
 distant object. In addition 
 there is a sensory reflex: when 
 sensory nerves are stimulated, as by scratching or tickling 
 the skin, both pupils dilate. 
 
 The consensual contraction is explained by the fact that 
 the light stimulus in one eye is carried by the optic nerve and 
 
 
 L R 
 
 
 s.© 
 
 cilO 
 
 ^Sc 
 
 1 
 
 ff ^" 
 
 ill 
 
 raAi>. 
 
 ORM 
 
 \\\ 11// "^° " 
 
 
 ^J NXXWI)/ ^^1 
 
 Vj 
 
 J ^^y V °i/ 
 
 ^*te--« 
 
 ^ OMN ^t.— '^ 
 
 Fig. 170.^Visual and Pupillary Reflex 
 Paths. L, Left eye; R, right eye; 
 ON, optic nerve; LT, left optic tract; 
 RT, right optic tract; POG, primary 
 optic ganglia ; OMN, oculomotor 
 nuclei; OR, optic radiations; OL, oc- 
 cipital lobe; CIL, ciliary ganglion. 
 Division of the fibres at 1 abolishes the 
 reaction of the pupil to light upon illu- 
 minating the left half of either retina. 
 At 2, the same result with right ho- 
 monymous hemiopia. At 3 right ho- 
 monymous hemiopia with preservation 
 of the reaction of the pupil to light. 
 
176 DISEASES OF THE IRIS 
 
 passes to both optic tracts and in this way to the nucleus ot 
 the third nerve of each side (Fig. 170). Blindness in one 
 eye .abolishes the direct reflex in this eye, but its consen- 
 sual reflex is preserved. 
 
 In certain pathological conditions, there may be loss of 
 light reflex, without interference with sight; this is seen, 
 for example, in paralysis of the iris as a result of the 
 use of a mydriatic or in oculo-motor paralysis. The 
 Argyll- Robertson pupil (reflex iridoplegia), so frequently a 
 symptom of locomotor ataxia, contracts with accommoda- 
 tion and convergence, but does not respond to light; it is 
 usually accompanied by miosis; it is explained by an inter- 
 ruption in the path from the optic nerve to the oculo-motor 
 nucleus, the connections of the centres for accommodation 
 and convergence remaining unaffected. 
 
 The characteristics of the pupils — size, equality, and re- 
 flexes, are of great value in the diagnosis of various affections 
 of the nervous system and in the localization of cerebral 
 lesions. Hence it is important to be familiar with the afferent 
 and efferent routes which control the movements of the pupil 
 (Fig. 170, and Plate XXII). 
 
 The course of the afferent impulse is retina, optic nerve, 
 both optic tracts, corpus quadrigeminum, nuclei of origin of 
 the third nerve in the floor of aqueduct of Sylvius (there being 
 a communication between the two sides). The efferent im- 
 pulse travels on either side from these nuclei to the third 
 nerve, the ciliary ganglion, short ciliary nerves, to the iris. 
 
 Mydriatics and Miotics are described in the chapter on Ocu- 
 lar Therapeutics, and on p. 400. The hemiopic pupillary 
 reflex is explained on p, 291. 
 
CHAPTER XI 
 
 DISEASES OF THE CILIARY BODY 
 
 Anatomy. — ^The ciliary body is that part of the tunica vaaculosa 
 which extends backward from the base of the iris to the anterior part 
 of the choroid; it consists of the ciliary processes and of the ciliary mus- 
 cle. A longitudinal section is of triangular shape, with a narrow base di- 
 rected forward, giving origin to the iris. The outer side of the triangle 
 is formed by the ciliary muscle; the inner side can be divided into two 
 parts: an anterior, which bears the cihary processes, and a posterior 
 portion, which is smooth. 
 
 The ciliary muscle (the muscle of accommodation) consists of non- 
 striated muscular fibres arranged in bundles, anastomosing with one 
 another frequently so as to form a sort of plexus, and running in three 
 different directions — meridional, radiating, and annular. The propor- 
 tion between circular and longitudinal fibres varies according to the 
 refractive condition of the eye; the circular set is well developed in 
 hyperopia (Fig. 304), but atrophied in myopia (Fig. 305). When the 
 cihary muscle contracts, it draws the ciliary processes and choroid for- 
 ward and inward, thus relaxing the suspensory ligament and allowing 
 the lens to become more convex. 
 
 The ciliary processes consist of about seventy folds or thickenings, 
 arranged meridionally, so as to form a circle. They have the same 
 structure as the rest of the choroid, but are even more vascular. They 
 serve to secrete the nutrient fluids in the interior of the eye which nour- 
 ish neighboring parts, especially the cornea, lens, and part of the vit- 
 reous. The inner surface of the ciliary body is covered by three layers: 
 externally, a homogeneous membrane continuous with the posterior 
 limiting membrance of the iris; next, pigment epitheUum; internally, 
 next to the vitreous, a layer of cylindrical non-pigmented cells. 
 
 The cihary body is supphed by branches from the greater circle of 
 the iris and by the anterior cihary arteries. The veins, constituting the 
 greater part of the ciliary processes, pass backward to the venae vorti- 
 cosse of the choroid. A part of the veins from the cUiary muscle pass 
 backward, pierce the sclera, and run beneath the conjunctiva with the 
 anterior cihary arteries. These constitute the violet subconjunctival 
 vessels seen running backward in ciliary injection and in deeper con- 
 gestion (glaucoma). They anastomose with the conjunctival veins, and 
 communicate with Schlemm's canal. The ciliary body is richly sup- 
 phed with nerves, especially the ciliary muscle in which there is a nerve 
 plexus with ganghon cells, 
 
 177 
 
178 DISEASES OF THE CILIARY BODY 
 
 CTCIilTIS 
 
 As already pointed out, iritis is frequently associated with 
 cyclitis {iridocyclitis). While unmixed cases of cyclitis occur, 
 they are uncommon; usually when the ciliary body is inflamed 
 the adjacent portions of the uveal tract (iris and choroid) 
 participate, and the disease is, from the start or soon after- 
 ward, an inflammation of iris, ciliary body, and choroid. 
 
 Practically, the term iridocyclitis is reserved for those cases 
 in which there are pronounced symptoms of iritis, and in ad- 
 dition the following evidences of participation of the ciliary 
 body: Tenderness in the ciliary region, swelling of the upper 
 lid, deposits upon Descemet's membrane, abnormal tension 
 (increase or decrease), and a greater interference with vision 
 than can be explained by changes in the anterior chamber 
 (due to opacities of the vitreous and exudation in the pupil- 
 lary space). 
 
 Symptoms. — The symptoms of cyclitis are those of iritis, 
 plus the additional ones just mentioned. Cyclitis or irido- 
 cyclitis is always a serious affection; the inflammation is pro- 
 nounced, and the changes in the eye may be disastrous; it 
 often causes destruction of the eyeball. 
 
 Varieties. — Cyclitis (Iridocyclitis) may be divided into (1) 
 simple, (2) plastic, (3) purulent, and (4) sympathetic. 
 
 Simple Cyclitis (Serous Cyclitis, "Serous Iritis," Chronic 
 Iridocyclitis, Uveitis). — This form occurs in young adults, is 
 chronic in its course, likely to relapse, and apt to involve both 
 eyes. 
 
 Symptoms vary a great deal in intensity. They include 
 those of iritis with the special signs of implication of the 
 ciliary body mentioned above. The exudation consists of 
 serum and leucocytes; the latter are precipitated upon the 
 posterior surface of the cornea and are sometimes pigmented; 
 in this situation the collection of larger and smaller dots of 
 exudate forms a triangular area over the lower part of the 
 cornea, apex above (Fig. 162, Plate XI). This peculiarity 
 has given rise to the terms keratitis punctata and descemetitis 
 as synonyms, though objectionable ones, for this disease. 
 
SEROUS CYCLITIS 179 
 
 Sometimes a number of spots coalesce and form small masses 
 to which the name " mutton-fat " deposits has been given. 
 The anterior chamber is deeper than normal and the aqueous 
 may be slightly turbid. The pupil is somewhat dilated. 
 Tension is apt to be increased at first and lowered later, or 
 there may be alternations of increase and decrease. There are 
 numerous dust-like opacities in the vitreous, and the latter 
 may lose its normal consistency and become fluid. 
 
 Symptoms of irritation are apt to be very slight: the patient 
 complains chiefly of marked diminution of vision, with prob- 
 ably a little congestion, slight pain now and then, ocular 
 fatigue, and limited photophobia. 
 
 Complications. — Iritis, choroiditis, scleritis, and glaucoma. 
 
 Etiology. — The various causes of iritis are responsible also 
 for iridocyclitis. Rheumatic, gouty, debilitated, anaemic 
 and tuberculous individuals are predisposed. The disease is 
 often due to the influence of toxins of bacterial or other origin 
 derived from the teeth (pyorrhoea alveolaris), tonsils, pharynx, 
 nose, nasal accessory sinuses, and the genital tract of women, 
 or to intestinal auto-intoxication. 
 
 Prognosis varies with the severity of the disease: mild 
 cases may recover with good vision. More severe examples 
 may also get well with useful sight; but in such cases, there 
 is always danger of serious damage by attacks of glaucoma; 
 and after each exacerbation or relapse in the symptoms, the 
 eye may present additional damage, so that finally a softened, 
 disorganized globe may result, with loss of vision (atrophy of 
 the eyeball). 
 
 Treatment is that of iritis. With increased tension atro- 
 pine is not well borne and must be suspended; in such cases, 
 miotics may he employed or paracentesis of the anterior 
 chamber may be indicated. General treatment and the dis- 
 covery and removal of the etiological factor are of great 
 importance. In cases in which the cause remains undiscov- 
 ered, and in others, large doses of salicylates or mercury by 
 inunction are often used. 
 
 Plastic Cyclitis (Plastic Iridocyclitis). — This form is ac- 
 companied by very pronounced symptoms of iridocyclitis; it 
 
180 DISEASES OF THE CILIARY BODY 
 
 may be acute or subacute. The fain is severe; there is great 
 cihary tenderness; the circumcorneal congestion is marked, the 
 color being often purpUsh as in episcleritis; the anterior cham- 
 ber is deep and the pupil often dilated owing to the retraction 
 of the periphery of the iris by the plastic exudation; tension 
 is reduced, or there may be alternations of + and — tension. 
 
 The disease is rarely limited to the ciliary body; it spreads 
 through the entire uveal tract and then constitutes plastic 
 uveitis. The exudation is formed in the anterior chamber, 
 pupil, behind the iris, and in the vitreous; it contracts sub- 
 sequently and causes detachment of the retina with complete 
 blindness. 
 
 The degenerated eyeball shrinks, and the condition is then 
 known as atrophy of the eyeball. The affection may now 
 become quiescent; but from time to time there are apt to be 
 attacks of pain, and the shrunken eyeball is often a constant 
 menace to the other eye. This form of inflammation has a 
 great tendency to cause sympathetic uveitis in the other eye 
 (sympathetic ophthalmitis). Though the disease is capable of 
 being cured in the early stages and leaving the eye in a more 
 or less useful condition, the majority of such eyes are lost. 
 
 The cause is usually aninjury in the ciliary region, either as 
 a result of violence or after operations upon the eyeball, espe- 
 cially cataract extraction. The treatment is that recom- 
 mended for simple iridocyclitis. 
 
 Purulent Cyclitis (Puruleni Iridocyclitis) is an inflam- 
 mation of the ciliary body with the formation of pus. It is 
 always an iridocyclitis and as such can be divided into two 
 varieties: 
 
 In the non-septic form, the term " purulent " merely refers 
 to the presence of pus in the anterior chamber; the course of 
 the disease resembles that of acute iritis, and its prognosis is 
 equally favorable. 
 
 In the second class of cases, the one usually meant when 
 purulent iridocyclitis is spoken of, there is a septic inflamma- 
 tion of the ciliary body, iris, and choroid, with the formation 
 of pu^. Such an inflammation may be set up by septic emboli 
 after puerperal and surgical pysemia, meningitis, cerebro- 
 
PURULETSIT IRIDOCYCLITIS 181 
 
 spinal meningitis, etc. (metastatic). But the usual cause of 
 purulent iridocyclitis is an injury in the ciliary region, includ- 
 ing operative wounds; also infected ulcers of the cornea. 
 
 The symptoms are always pronounced. Besides those pres- 
 ent in a severe case of iridocyclitis, there is apt to be more 
 congestion of the conjunctiva with chemosis, and swelling of 
 the lids. Pus forms in the anterior chamber and in the 
 vitreous; if the usually clouded cornea and aqueous permit, a 
 yellow reflex is obtained from the vitreous. 
 
 Though the disease may yield to treatment when seen early, 
 the prognosis is always grave. The cases following pyaemia, 
 septicaemia, and meningitis soon involve the entire uveal tract 
 in the purulent process and terminate in blindness, shrinking 
 of the eyeball causing atrophy of the globe. In other cases 
 the disease extends to all the structures of the eyeball and 
 terminates in panophthalmitis (p. 192). The treatment is the 
 same as in other forms of iridocyclitis. 
 
 Sympathetic Iridocyclitis is described in Chapter XIII, 
 under Sympathetic Ophthalmitis (p. 188). 
 
 Injuries of the Ciliary Body. — The ciliary region, repre- 
 sented by a ring about 6 mm. wide around the cornea, is 
 known as the "dangerous zone," because penetrating wounds 
 in this situation are apt to-set up plastic cyclitis, which may be 
 followed by sympathetic ophthalmitis. In wounds of this 
 region, if there be no prolapse of the ciliary body and no for- 
 eign body in the eye, a bandage may be applied after thor- 
 ough cleansing, and a suture used if the wound be large and 
 gaping. Prolapses of the iris and ciliary body are usually 
 excised if it is thought likely that the eye can be saved. If 
 the woimd is very extensive, sight lost, and it is evident that 
 the form of the eyeball cannot be preserved, enucleation is 
 indicated. Additional details of treatment are given in the 
 paragraphs on Injuries of the Sclera (p. 162) and on Sym- 
 pathetic Ophthalmitis (p. 188). 
 
CHAPTER XII 
 
 DISEASES OF THE CHOROID 
 
 Anatomy and Physiology. — The choroid is a dark brovm membrane 
 placed between the sclera and the retina, extending from the ora serrata 
 to the opening for the optic nerve. It consists mainly of blood-vessels, 
 united by deMcate connective tissue containing numerous pigmented 
 cells; these vessels are arranged according to their cahbre into three 
 superimposed layers. 
 
 This vascular structure is bounded on either side by a non-vascular 
 membrane; accordingly, the choroid can be divided into^ive layers: (1) 
 Externally, the suprachoroid, connected with the sclera by loose con- 
 nective tissue. (2) The layer of large vessels, chiefly anastomosing veins, 
 the spaces between which are filled with connective tissue and pigment 
 cells; the arteries are the short ciliary; the veins are arranged in curves 
 {vasa vorticosa) converging to four or five principal trunks which pierce 
 the sclera near the equator of the eyeball. (3) The layer of medium- 
 sized vessels. (4) The layer of capillaries (chorio-capillaris). (5) The 
 lamina vitrea, a homogeneous membrane which is placed next to the 
 pigmentary layer of the retina. 
 
 The function of the choroid is chiefly to serve as a nutrient organ for 
 the retina, vitreous, and lens. It forms the dark coating of the interior 
 of the eyeball. 
 
 Inflammations of the Choroid (choroiditis) may be (1) exv^ 
 .dative or nonsuppurative, and (2) suppurative. 
 
 EXXJDATrVE OR NON-SXJPPTTRATrVE CHOROIDITIS 
 
 Varieties. — ^Exudative choroiditis (Plates XII, XIII, XIV) 
 is classified, according to the location of the foci of inflamma- 
 tion, into the following principal forms : (1) Diffuse, (2) Dis- 
 seminated, (3) Circumscribed, (4) Anterior, (5) Central, (6) 
 Syphilitic, and (7) Myopic. It is of frequent occurrence and 
 is observed at all ages; it is usually chronic in its course, 
 though occasionally with acute onset. In many instances 
 the disease involves the retina as well as the choroid, and is 
 then properly spoken of as choroidoretinitis or retinochoroi- 
 ditis. It will be of advantage to describe Exudative Choroi- 
 
 182 
 
EXUDATIVE CHOROIDITIS 183 
 
 ditis in General, before giving the distinctive features of the 
 several varieties. 
 
 Subjective Symptoms. — There are disturbances of sight: 
 Diminution of vision due to opacities in the vitreous; also 
 distortion of objects (metamorphopsia), — either micropsia, 
 when objects appear too small, or ^^^^ 
 
 macropsia, when they appear too ^^^^^^^^^ 
 large — as a result of displacement >^^0^^^5^^^ 
 of the retinal elements over the //^I^^PS ^^V^^^ 
 inflamed focus; and a reduction or [Tyfr^^ ^^^^B 
 loss of vision in that part of the field yX^^^^vp^^^K 
 which corresponds to the seat of exu- \9tKfi^^^m 
 dation. There are often flashes of N^^^^^^^ 
 light, sparks, or bright circles (pho- ^^^^^^ 
 
 ,° .' ^ . ' , ° T ii. li FiG.171.— PeripheralScotomata 
 
 topsise) before the eyes. In the later ^ Exudative choroiditis, 
 stages there may be defects in the field 
 
 of vision, both scotoma (Fig. 171) and peripheral contraction. 
 There is no pain unless the iris or ciliary body is involved. 
 
 Objective Symptoms. — There are no external signs, but the 
 ophthalmoscope reveals a well-marked picture. There are 
 patches of exudation varying in size, shape, and position. At 
 first these areas are yellowish (sometimes greenish-gray) in 
 color, with ill-defined margins; the retinal blood-vessels are 
 seen to be lifted and to pass over them. Later, after several 
 weeks or months, the exudation becomes absorbed, leaving 
 patches of choroidal atrophy; the latter appear as whitish areas 
 (the sclera showing through) often presenting distinctly vis- 
 ible choroidal vessels, and marked with more or less pigment, 
 especially at their margins. Usually the vitreous is involved, 
 and then there are opacities of this medium. Very often the 
 retina becomes atrophied opposite the patches just described. 
 The optic disc may participate and be hypersemic at first and 
 later present a dirty yellowish-red color with blurred margins, 
 a condition often spoken of as " choroiditic atrophy." 
 
 Complications. — ^From this description it will be seen that 
 neighboring structures are frequently implicated: Iris, retina, 
 optic nerve, vitreous, and sclera; choroiditis may also cause 
 posterior polar cataract. 
 
184 DISEASES OF THE CHOROID 
 
 Etiology. — Frequently some constitutional disease, espe- 
 cially acquired and hereditary syphilis, but also ansemia, 
 scrofula, and tuberculosis; many examples are found in my- 
 opia; it may depend on septic infection from the teeth, oral 
 and nasal cavities, or upon intestinal auto-intoxication; many 
 cases with obscure origin are spoken of as idiopathic. 
 
 Prognosis depends upon the position of the patches of exu- 
 dation with subsequent atrophy. A single patch involving 
 the macular region will seriously impair vision. On the other 
 hand, the process may extend over a considerable part of the 
 fundus and yet vision remain good, if the macula escapes. 
 
 Treatment. — Removal of the etiological factor; iodides and 
 mercury in syphilitic cases; inunctions of mercury are often 
 used with success even in non-syphilitic cases; tuberculin in 
 suitable patients; attention to the general health; diaphoresis 
 is often valuable. Rest of the eyes, avoidance of bright light 
 by the use of smoked glasses, sometimes a darkened room; 
 subconjunctival injections of salt solution are often useful. 
 
 Distindive features in the different varieties of exudative 
 choroiditis will be briefly considered: 
 
 1. Diffuse Choroiditis (Fig. 172, Plate XII).— In this form 
 the patches of exudation are of considerable size, gradually 
 shading into the surrounding portions of the choroid; later, 
 when atrophy occurs, the coalescence of these spots forms 
 large areas of white or yellowish-white color, more or less pig- 
 mented, representing the exposed sclera. 
 
 2. Disseminated Choroiditis (Fig. 173, Plate XII) pre- 
 sents numerous round or irregular spots with pigmented mar- 
 gins, scattered over the fundus, beginning in the periphery, and 
 gradually encroaching upon the centre. The entire fundus 
 may be studded, and yet vision remain good if the macular 
 region escapes. This form of choroiditis runs a very chronic 
 course. After a time, it may be accompanied by opacities of 
 the vitreous and choroiditic atrophy of the optic nerve. 
 
 3. Circumscribed Choroiditis is a variety occurring not 
 infrequently in young individuals in whom a single patch of 
 yellowish-white or bluish-green color with fading edges is 
 seen near the disc or macula or more peripherally, accom- 
 
PLATE XII 
 
 Fl*;. 172. — Diffuse Exudative f'horoirjitis. 
 
 Fi(i. 173. — Di.sseminatecl rhoroiditis. 
 
PLATE XIII 
 
 Fig. 174. — Choroiditis of Myopia. 
 
 Fig. 1..5. — Contral Clioroiditis. 
 
EXUDATIVE CHOROIDITIS 185 
 
 panied often by deposits on Descemet's membrane and by 
 vitreous opacities, but causing little damage to vision unless 
 the macular region is invaded. 
 
 4. Anterior Choroiditis, presenting foci of exudation even- 
 tually appearing as black spots in the extreme periphery of 
 the fundus, is seen in high myopia and in hereditary syphilis. 
 
 5. Central Choroiditis (Fig. 175, Plate XIII) is a form in 
 which the changes are limited to the region of the macula; 
 it occurs most frequently in high myopia, but also in syphilis 
 and after contusions of the eyeball. It results in serious 
 interference with vision and causes central scotoma. It also 
 occurs as a result of senile changes {central senile choroiditis). 
 
 6. Syphilitic Choroidoretinitis (Fig. 176, Plate XIV) is the 
 name given to inflammation of the choroid, associated with 
 retinitis and changes in the vitreous, which occurs in syphilis. 
 At first there are diffuse cloudiness of the retina, numerous 
 exudations in the choroid, especially in the region of the 
 macula, and fine, dust-like opacities of the vitreous. Later, 
 the cloudiness of the retina is replaced by atrophy, there are 
 atrophic patches of the choroid, numerous spots of pigment 
 in the periphery of the fundus, and opacities of the vitreous. 
 
 7. Myopic Choroiditis; Posterior Staphyloma, or Sclero- 
 choroiditis Posterior. — The fundus of nearsighted eyes, espe- 
 cially if the myopia be of high degree, very often presents 
 characteristic changes (Fig. 174, Plate XIII, and Fig. 177, 
 Plate XIV). Owing to the elongation of the eyeball, there 
 is a bulging of the sclerotic at the posterior pole and atrophy 
 of the choroid in this situation. This shows itself in a white 
 crescent {myopic crescent) situated usually to the outer side of 
 the disc, varying in size, and sometimes encircling the papilla. 
 It is known as posterior staphyloma or sclerochoroiditis pos- 
 terior; it is often incorrectly called " conus." 
 
 When this crescentic or annular patch is separated from 
 healthy choroid by a sharply defined margin, often pigmented, 
 it is a sign that the process has come to a standstill. But 
 when the border is ill-defined, it indicates that the changes 
 are advancing {progressive myopia); such knowledge is of 
 great importance in emphasizing the necessity for attention 
 
186 DISEASES OF THE CHOROID 
 
 to ocular and general hygiene. The size of the staphyloma 
 is usually, but not always, proportionate to the degree of 
 myopia. More or less superficial atrophy of the choroid is 
 often observed in myopia of high degree, allowing the larger 
 choroidal vessels to become plainly visible. Besides choroi- 
 ditis in the macular region, there may be patches of choroidal 
 atrophy in other parts of the fundus; these often coalesce with 
 the posterior staphyloma, so that an extensive white area is 
 seen, spotted or bordered with more or less pigment. The 
 early changes in the macular region may be represented by 
 fine lines or fissures. Hemorrhages, especially in the macular 
 region, and opacities of the vitreous also occur in myopia of 
 high degree. 
 
 SUPPXTRATIVE IBIDOCHOKOIDITIS 
 
 In this affection, the choroid, ciliary body, and iris are in- 
 volved in a suppurative inflximmation which leads to the de- 
 struction of the eyeball. In most cases the process spreads to 
 all the structures of the eyeball and panophthalmitis results 
 (p. 192). Rarely, the inflammation is limited to the choroid 
 (suppurative choroiditis), the purulent exudate forming an 
 abscess of the vitreous with no external evidences of inflamma- 
 tion but with loss of vision. 
 
 Symptoms. — ^Those of iridocyclitis, already given, are acute 
 and severe. There is much pain, and marked conjunctival 
 congestion, chemosis, and swelling of the lids. The cornea 
 becomes clouded, and pus appears in the aqueous and vitreous 
 so that no details of the fundus are visible. Sight is rapidly 
 lost. There is often considerable constitutional disturbance. 
 
 In those cases in which the process remains limited to the 
 uveal tract and vitreous, after the acute symptoms subside, 
 a sightless, degenerated, and atrophied eyeball remains. A 
 yellowish or grayish-yellow reflex is then obtained from the 
 interior of the eye, due to the purulent degenerated mass, 
 known as pseudo-glioma on account of its resemblance in color 
 to glioma of the retina. 
 
 Etiology. — Infection of the interior of the eye by pyogenic 
 microbes, either from without or from within the body. Ectog- 
 
PLATE XIV 
 
 Fig. 176. — Sypliilitic Choroirlnrclinitis. 
 
 Fig, 177. — Posterior Staphyloma. 
 
SUPPURATIVE IRIDOCHOROIDITIS 187 
 
 enous infection occurs most frequently from penetrating 
 wounds, including operations, perforating ulcers, thin corneal 
 scars, and prolapse of iris. Endogenous infection results from 
 septic embolism (metastatic ophthalmia) and is seen most 
 frequently in puerperal pyaemia, also surgical pyaemia; exten- 
 sion from orbital cellulitis; also in meningitis and cerebro- 
 spinal meningitis, especially in children, and sometimes 
 infectious diseases. 
 
 Treatment. — It is impossible to save sight. Pain should 
 be relieved by morphine and by the local applications of hot, 
 moist compresses. If the process has involved all the ocular 
 structures, the treatment of panophthalmitis is indicated (p. 
 192). 
 
 Coloboma of the Choroid is a congenital defect of the cho- 
 roid and retina, showing itself in a large white patch, represent- 
 ing the exposed sclera; it is usually situated below the disc. 
 The retinal vessels are seen passing across this patch. There 
 is a scotoma corresponding to the defect. This condition is 
 sometimes associated with coloboma of the iris and other 
 congenital defects of the eye. 
 
 Rupture of the Choroid sometimes results from contusions 
 of the eyeball. The immediate effect of such an injury is an 
 extravasation of blood into the vitreous. After this is ab- 
 sorbed a long, yellowish-^hite streak with pigmented edges, 
 curved with its concavity toward the disc, is seen, usually in 
 the neighborhood of the disc and to its outer side. 
 
 Tubercle of the Choroid occurs in acute miliary tubercu- 
 losis and in tuberculous meningitis. The tubercles appear as 
 small, yellowish-white spots with soft, fading edges, vary in 
 number, are 1 or 2 mm. in diameter, and are found near the 
 disc, in the macular region, or scattered over the fundus. 
 They resemble the spots seen in recent cases of disseminated 
 choroiditis but are smaller. Tuberculosis rarely assumes the 
 form of a solitary irregular mass which may be mistaken for 
 glioma of the retina or sarcoma of the choroid. 
 
 Sarcoma of the Choroid (see Chapter XIV). 
 
CHAPTER XIII 
 
 DISEASES OF THE WHOLE UVEAL TRACT 
 UVEITIS 
 
 As its name implies, uveitis is an inflammation of the whole 
 uveal tract: iris, ciliary body, and choroid. There are two 
 forms: (1) serous and plastic, and (2) purulent. Both forms 
 have been described in cormection with iridocyclitis, which, 
 as already explained, is generally merely part of a uveitis. 
 There are, however, two special varieties: (1) Sympathetic 
 Uveitis, generally known as Sympathetic Ophthalmitis, and 
 (2) the form of Purulent Uveitis known as Panophthalmitis. 
 
 SYMPATHETIC OPHTHALMITIS 
 
 Sympathetic Ophthalmitis (Sympathetic Ophthalmia, 
 Sympathetic Uveitis) is a serous or plastic inflammation of 
 the uveal tract in one eye due to the effects of a similar inflam- 
 mation in the other. 
 
 Etiology and Occurrence. — This inflammation is almost 
 always due to a traumatic iridocyclitis of the first eye as a 
 result of a perforating injury; the most common example of 
 such injury is an accidental or operative wound involving the 
 ciliary region, especially if the iris or cihary body be entangled 
 in the woimd. Foreign bodies retained in the eyeball are also 
 apt to excite this disease. Sometimes it results from the 
 iridocyclitis following perforating wounds or ulcers of the 
 cornea complicated by incarceration of the iris, or occurring 
 with intraocular tumors. Rarely it occurs without any 
 perforating lesion. Suppurative inflammations of the eye- 
 ball are not usually exposed to the risk of sympathetic 
 ophthalmitis. 
 
 It is, fortunately, not of very frequent occurrence, for it is 
 a most serious disease, on account of its tendency to cause 
 blindness. It occurs most frequently in the young, especially 
 in children, but may be met with at any age. It was formerly 
 
 188 
 
SYMPATHETIC OPHTHALMITIS 189 
 
 more common than it is at present on account of modern 
 antiseptic methods. It usually begins between four and 
 eight weeks after the injury in the exciting eye, rarely before 
 three weeks; it may, however, occur many months or even 
 years after the injury. 
 
 The ey€ which has been originally affected is known as the 
 exciting eye; the one secondarily involved, as the sympathizing 
 eye. 
 
 Symptoms. — In most cases, but not invariably, the disease 
 presents a stage known as sympathetic irritation; it is very 
 important to recognize this stage, since removal of the excit- 
 ing eye at this period will prevent the progression of the 
 affection from irritation to actual inflammation. 
 
 The Symptoms of Sympathetic Irritation. — The sympathiz- 
 ing eye is " irritable "; there are marked photophobia and lac- 
 rymation; neuralgic pain in the eye and neighboring parts; 
 dimness of vision occurs when the eyes are used for near work; 
 there may be bright and colored sensations. 
 
 The exciting eye usually presents an iridocyclitis or uveitis, 
 which may be slight or severe; when the sympathizing eye 
 becomes affected, there may be symptoms of irritation and 
 marked tenderness over the ciliary region in the exciting eye. 
 
 These symptoms of irritation in the sympathizing eye may 
 be intermittent; each attack may last a number of days or 
 weeks, then subside, and recur a number of times. They may 
 finally disappear entirely. But, as a rule, if the exciting eye 
 is not excised, sympathetic inflammation results. 
 
 The Symptoms of Sympathetic Inflammation. — These may 
 follow directly upon those of irritation, or may occur after the 
 sympathizing eye has been quiet for a time. They may begin 
 acutely or insidiously. When once established the inflam- 
 mation is chronic, and its duration is months or even one or 
 two years. In the majority of cases blindness results, though 
 occasionally, if the inflammation be mild, useful vision may 
 be preserved. 
 
 The symptoms are photophobia, lacrymation, dimness of 
 vision, and tenderness in the ciliary region. There will be 
 circumcorneal injection, punctate deposits upon Descemet's 
 
190 DISEASES OF THE WHOLE UVEAL TRACT 
 
 membrane, increased depth of the anterior chamber, contracted 
 pupil, and increased tension. 
 
 In mild cases (serous type) the symptoms may not pass 
 beyond those of serous cyclitis or iridocychtis; but usually 
 they develop into a plastic uveitis including iris, ciliary body, 
 and choroid, and giving the following signs : The iris is thick- 
 ened, its color changed, and its markings obliterated; it is 
 firmly bound down by numerous and extensive posterior 
 synechias. The plastic exudation fills up the pupil and more 
 or less of the anterior chamber, which becomes shallow. Ten- 
 sion is diminished. The choroid and retina participate in the 
 plastic inflammation, the vitreous presents numerous opac- 
 ities, and the lens becomes opaque. Finally, there is detach- 
 ment of the retina, the eyeball shrinks and passes into the 
 condition of atrophy. 
 
 Occasionally sympathetic disease occurs in the form of a 
 neuroretinitis without extension to the uveal tract, or as a 
 choroiditis. 
 
 Theories of Transmission. — The mode of transmission is 
 not definitely known. The theories which have been pro- 
 pounded are: (1) Infection spreading through the sheath of 
 the optic nerve of one side to the chiasm and sheath of the 
 optic nerve of the other eye; (2) irritation through the ciliary 
 nerves; (3) the action of a toxin generated by bacteria which 
 have entered the exciting eye, reaching the second eye by 
 lymph channels; (4) metastasis through the blood current, of 
 some form of bacteria which are pathogenic for the eye only; 
 since such bacteria have not been isolated, it is thought that 
 the noxious agent is a toxin of these bacteria. At present, 
 the last is regarded as the most probable explanation. 
 
 Treatment. — Prophylactic treatment is of the greatest im- 
 portance, and refers to the care of the injured eye on the 
 lines explained in dealing with iridocyclitis, including full 
 doses of mercury up to the point of salivation and large 
 amounts of sodium salicylate. We should enucleate the in- 
 jured eye if it be sightless, or its condition such (especially 
 when the ciliary region is involved) that we cannot hope to 
 preserve useful vision; this is particularly imperative if it is 
 
SYMPATHETIC OPHTHALMITIS 191 
 
 irritable, has ciliary tenderness, presents persistent signs of 
 iridocyclitis, or contains a foreign body which cannot be 
 extracted. 
 
 When, however, there is useful vision in the injiu-ed eye, or 
 a good chance of obtaining fair sight, the question of enuclea- 
 tion is often a difficult one to decide, since symptoms of sym- 
 pathetic irritation may appear and then subside, and yet sym- 
 pathetic inflammation never develop. In such cases we are 
 often justified in waiting, if the injured eye remain quiet and 
 free from inflammation, providing we can keep such a patient 
 under constant observation, so that we are able to enucleate 
 when warned by repeated or persistent symptoms of sjon- 
 pathetic irritation. 
 
 Although enucleation of the injured eye usually has a favor- 
 able influence upon the sjonpathetic process during the stage 
 of irritation, it has no effect upon the progress of the disease 
 after sympathetic inflammation has made its appearance; the 
 exciting eye may ultimately possess better vision than its 
 sympathizing fellow. Hence, under such circumstances, the 
 exciting eye should not be removed if it possesses vision; if 
 blind and exhibiting signs of inflammation, it should be enu- 
 cleated, even with the knowledge that this step will not cure 
 the sympathetic ophthalmia, since its presence may aggravate 
 the condition in the sympathizing eye. 
 
 The treatment of the sympathetic ophthalmia itself consists 
 in the use of atropine (imless this seems to aggravate the 
 symptoms), dionine, hot compresses, reasonable confinement 
 to a shaded room, and smoked coquilles; diaphoresis; leeches 
 to the temple are sometimes of advantage. Mercurialization 
 is frequently resorted to up to the point of salivation. Large 
 doses of sodium salicylate are sometimes effective. Salvarsan 
 has given very gratifying results. Since the disease is of 
 lengthy duration, the general health of the patient must be 
 looked after. 
 
 Though the prognosis is unfavorable and most cases end in 
 blindness, the treatment must be carried out rigidly and pa- 
 tiently; in some cases at least, especially if the inflammation 
 be of the serous type, fair vision may ultimately be obtained. 
 
192 
 
 DISEASES OF THE WHOLE UVEAL TRACT 
 
 riG. 178.— Phthisis Bulbi. 
 
 PANOPHTHALMITIS 
 
 An intense suppurative inflammation of the entire uveal tract, 
 which fills the eyeball with pus, extends to all the structures of 
 
 the eye, and ends in complete 
 destruction of this organ. It 
 is due to infection. It differs 
 from suppurative iridocho- 
 roiditis in spreading beyond 
 the uveal tract and involv- 
 ing all the structures of the 
 eye. 
 
 Etiology. — Identical with 
 that of suppurative iridocho- 
 roiditis (p. 186). 
 
 Symptoms (already de- 
 scribed in connection with 
 suppurative iridochoroiditis, 
 p. 186) are apt to be acute and severe. The disease is usu- 
 ally ushered in by a rise of temperature, general febrile 
 symptoms, headache, and sometimes vomiting. There are 
 severe pain in the ej^eball, rapid loss of sight, intense ciliary 
 and conjunctival congestion, marked chemosis, and sioelling 
 and redness of the lids (Fig. 163, Plate XI). The iris 
 soon becomes involved, the anterior chamber and vitreous 
 become filled with pus, the cornea is clouded and 3fellow (Fig. 
 164, Plate XI), and tension increased. There is infiltration 
 of Tenon's capsule, followed by exophthalmos and limitation 
 of the movements of the eyeball. 
 
 Pus usually breaks through the anterior portion of the 
 sclera, after which the pain and other sj^mptoms sxibside; in 
 the course of several weeks the process has run its course, 
 leaving a shrunken, sightless eyeball (phthisis bulbi. Fig. 178). 
 Prognosis is always unfavorable: sight is invariably lost. 
 The condition does not cause sympathetic ophthalmia, except 
 in rare instances. 
 
 Treatment. — The indications are to alleviate pain by the 
 use of morphine and hot, moist compresses, and to incise the 
 
PANOPHTHALMITIS 193 
 
 sclera so as to allow the escape of pus. If the case is seen 
 early, thorough and repeated cauterization of the focus of 
 infection with the electro-cautery, the introduction of small 
 rods of iodoform into the anterior chamber, paracentesis and 
 frequent irrigation of the anterior chamber, and mercurializa- 
 tion may, in rare instances, be of service. It is not consid- 
 ered advisable to enucleate in the inflammatory stage, on 
 account of the danger of setting up meningitis 
 
CHAPTER XIV 
 
 INTRAOCULAR TUMORS 
 
 Intraocular tumors are rare. Their recognition is, how- 
 ever, important, since early enucleation of the eyeball may 
 save life. There are two principal varieties: (1) Sarcoma of 
 the Choroid, and (2) Glioma of the Retina. 
 
 SARCOMA OF THE CHOROID 
 
 This malignant growth occurs in adults, usually between 
 the ages of forty and sixty. It is always primary, single, and 
 involves one -eye only. It is composed of round or spindle 
 cells, or both, usually pignjented (melanosarcoma), but some- 
 times non-pigmented (leucosarcoma). 
 It forms a rounded mass which springs 
 from the outer layers of the choroid, 
 most commonly near the posterior pole, 
 and grows inward, pushing the retina 
 before it (Fig. 179). 
 
 Symptoms. — There are four stages: 
 In the first or quiet stage, there will 
 be a defect in the field and diminution in 
 Fig. 179.— Sarcoma of the gigj^i depending upon the cxact seat of 
 
 Choroid, with Detach- , ^ ° , , , , , 
 
 ment of the Retina. the tumor. With the ophthalmoscope 
 a yellowish, brovm, or black mass may 
 be seen, covered by circumscribed detached retina. Some- 
 times the retina is more diffusely detached and thus obscures 
 this picture. The anterior ciliary veins may be found di- 
 lated near the seat of the growth. This stage usually 
 lasts about a year. 
 
 In the second or glaucomatous stage, the tumor enlarges in 
 size and gives rise to pain, increased tension, and other symp- 
 toms of inflammatory glaucoma. Increase in the retinal de- 
 tachment and other changes now prevent a view of the inte- 
 rior of the eye. 
 
 194 
 
SARCOMA OF THE CHOROID 195 
 
 In the third or extraocular stage, the tumor bursts through 
 the globe and then increases very rapidly in size, and ulcer- 
 ates with accompanying hemorrhages. In most cases it per- 
 forates anteriorly, and a dark mass is seen. If it perforates 
 posteriorly, exophthalmos results. It soon implicates neigh- 
 boring struMures, including the brain. 
 
 The fourth stage is distinguished by the occurrence of 
 metastases, most frequently in the liver. 
 
 Differential Diagnosis. — Sarcoma of the choroid may be 
 mistaken for detachment of the retina, glaucoma, or possibly 
 glioma of the retina; the last, however, occurs only during 
 the first years of life. Ordinary detachment of the retina 
 usually occurs suddenly in a myopic eye, or after a blow, and 
 tension is diminished. From primary glaucoma sarcoma of 
 the choroid is distinguished by the fact that sight is involved 
 before the inflammatory symptoms appear, there are no pro- 
 dromal symptoms such as usually precede glaucoma, nor re- 
 missions in symptoms, one eye only is involved, and the 
 characteristic field of glaucoma (nasal limitation) is not 
 present. Transillumination is often valuable for diagnosis, 
 the pupil remaining dark when the opening of the instrument 
 is placed upon the sclera corresponding to the seat of the 
 tumor; when the sarcoma is situated near the posterior pole 
 this test is of no value. 
 
 Prognosis. — When the eye is enucleated early, cure results 
 in from 25 to 50 per cent, of cases. But even after early re- 
 moval of the eye, sarcoma of the choroid proves fatal in many 
 cases, chiefly as a result of metastasis, occurring within a few 
 years, in internal organs; much less frequently from local 
 recurrence in the orbit. 
 
 Treatment. — Enucleation as soon as the diagnosis is estab- 
 lished, cutting the optic nerve far back. It will be necessary 
 to remove the entire contents of the orbit if the growth has 
 broken through the globe. 
 
 GLIOMA OF THE RETINA 
 A malignant growth (Fig. 180), consisting of small cells 
 with soft basement substance and blood-vessels, developing 
 
196 INTRAOCULAR TUMORS 
 
 from the granular layers of the retina; it occurs in children 
 under five, usually in one eye, at times in both, and occasion- 
 ally in successive children of the same family. 
 S3rmptoms. — We distinguish three stages: 
 In the first or quiet stage there are no infiammatory symp- 
 toms. The ophthalmoscope shows small whitish or yellowish 
 masses with metallic lustre, growing into 
 the vitreous, the surface presenting newly 
 formed blood-vessels. The attention of the 
 parents is attracted by the striking yellow 
 reflex, easily seen through the pupil, which 
 is usually dilated; this symptom has given 
 rise to the synonym " amaurotic cat's eye." 
 In the second or inflximmatm-y stage 
 there are pain, increase of tension, and 
 
 Fig. 180.— Glioma of the ^ , , r . n , 7 
 
 Retina. othcr symptoms of mflammatory glau- 
 
 coma. The tumor increases in size and 
 extends into the vitreous. Very soon the growth can no 
 longer be seen on account of turbidity of the media. 
 
 In the third or extraocular stage there is bulging of the eye- 
 ball, both staphyloma and exophthalmos, and then perforation 
 takes place. The growth passes backward along the optic 
 nerve to the brain (in this way it becomes fatal), and forward 
 through the cornea and sclera, increasing in size rapidly, in- 
 volving all neighboring tissues, and forming a large vascular 
 and ulcerating mass. Metastases are rather rare. 
 
 Differential Diagnosis. — We must distinguish glioma from 
 pseudo-glioma (p. 186), the degenerated eyeball which is the 
 outcome of purulent iridochoroiditis following meningitis or 
 cerebro-spinal meningitis in children. In the latter affection 
 there is the history of a previous acute febrile disease with 
 inflammation of the eyeball, tension is diminished, the pupil is 
 not dilated and it may be irregular, the anterior chamber is 
 deepened at its periphery, there may be other signs of pre- 
 vious iritis, and the yellowish mass is flatter and is not cov- 
 ered by newly-formed vessels. When in doubt, such eyes 
 being always sightless, we should enucleate. 
 
 Treatment. — Enucleation as soon as possible, cutting the 
 
GLIOMA OF THE RETINA 197 
 
 optic nerve far back. If the growth has perforated, the en- 
 tire orbit must be cleaned out; even then there is danger of 
 recurrence. When excision is practised early there is a fair 
 chance of cure. Unless this is done death occurs within a 
 few years. 
 
CHAPTER XV 
 
 GLAUCOMA 
 
 Anatomy. — The aqueous chamber is bounded in front by the cornea, 
 behind by the. lens and its suspensory ligament, and laterally by the 
 hgamentum pectinatum and anterior portion of the ciliary body (Fig. 
 181). Its depth varies; it is comparatively 
 deep in the young, in myopic eyes, and 
 when the eye is focussed for distant ob- 
 jects. The iris divides the aqueous cavity 
 into an anterior and a posterior chamber 
 (Fig. 182). The former lies in front of the 
 iris. The latter is the annular space be- 
 tween the iris and the lens; since the iris 
 is in contact with the lens only at its pu- 
 pillary margin, this space increases in 
 depth from the pupil to the peripheral 
 border of the iris, and is triangular in 
 cross-section. The posterior communicates 
 with the anterior chamber by means of 
 the pupil. 
 
 The portion of the anterior chamber 
 where the sclerocorneal margin, iris, and 
 hgamentum pectinatum meet is known as 
 the angle or sinus of the anterior chamber 
 (often called the iris angle). This region is of great importance; upon 
 its integrity depends the proper circulation of the lymph which nour- 
 ishes the anterior portion of the ejteball. 
 
 The Hgamentum pectinatum is formed by the breaking up of Des- 
 cemet's membrane at the margin of the cornea, into bundles which 
 connect the sclera with the root of the iris. These elastic laminae are 
 covered by endothelium continued from Descemet's membrane. In 
 this way spaces are formed which are continuous with the cavity of the 
 aqueous, are lined with endothelium, and are known as the spaces of 
 Fontana. To their outer side, at the sclerocorneal junction, is Schlemm's 
 canal, a plexus of veins. 
 
 With the exception of the conjunctiva, no portion of the eyeball 
 contains lymphatic vessels; in place of such vessels and serving the 
 same function, there are lymph channels and lymph spaces. These may 
 be divided into those of the anterior and those of the posterior portion 
 of the eyeball. 
 
 198 
 
 Fig. 181. — Section of the Eye- 
 ball at the Sclero-eorneal 
 Junction, Showing Angle of 
 Anterior Chamber. S, Sclera; 
 C, cornea; /, iris; L, lens; 
 cm, ciliary muscle; Sch, canal 
 of Schlemm. 
 
THE LYMPH SPACES OF THE EYE 
 
 199 
 
 The anterior lymph spaces and eavities consist of the aqueous cham- 
 ber and the parts immediately around the iris angle. The anterior and 
 posterior chambers represent two large lymph spaces which collect the 
 lymph of the anterior portion of the eye. This lymph is known as the 
 
 aqueous humor, and consists of a clear, 
 watery fluid, containing very little al- 
 bumin, secreted by the cihary processes. 
 It first passes into the posterior cham- 
 ber, then through the pupil into the an- 
 terior chamber, and leaves the eye 
 through the spaces of the ligamentum 
 pectinatum (Fontana's spaces) and 
 Schlemm's canal, passing into the an- 
 terior ciliary veins; a portion passes into 
 the lymph spaces of the iris, and thence 
 to the suprachoroidal lymph space. 
 
 The posterior lymph passages consist 
 of the hyaloid canal of the vitreous, 
 and of the suprachoroidal space (be- 
 tween choroid and sclera), communicat- 
 ing with Tenon's space along the vense 
 vorticosse; both have for an outlet the 
 supravaginal and infravaginal 
 of the optic nerve. 
 
 Fig. 182. — Diagrammatic Section 
 of the Anterior Portion of the 
 Eyeball showing: (1) Upper 
 Conjunctival Sac, (2) Lower 
 Conjunctival Sac, (3) Anterior 
 Chamber, (4) Posterior Cham- 
 ber 
 
 GLAtrCOMA 
 
 Glaucoma is an important and 
 common disease of the eye, which has for its characteristic 
 sign an increase of intraocular tension. 
 
 Varieties. — It is (1) primary, when occurring without ante- 
 cedent ocular disease, and (2) secondary, when it follows as a 
 result of some pre-existing disease of the eye. 
 
 Primary Glaucoma occurs under two forms: 1, Inflam- 
 matory or Congestive, and 2, Non-inflammatory or Non-con- 
 gestive, usually spoken of as Sim^ple. 
 
 The inflammatory variety is again divided into 1, acute, and 
 2, chronic; intermediate cases are sometimes called subacute. 
 
 These variations in clinical types of primary glaucoma are 
 explained by the rapidity with which the increase of intra- 
 ocular pressure shows itself and the height to which it rises. 
 When the increase of tension is rapid, the inflammatory type 
 results; when gradual, the eyeball accommodates itself to the 
 
200 GLAUCOMA 
 
 altered conditions, and symptoms of inflammation or conges- 
 tion are absent; tlie disease is then known as simple glaucoma 
 (non-inflammatory or non-congestive glaucoma) ; this type is 
 always chronic in its course. 
 
 Inflammatory glaucoma presents a clinical picture which is 
 quite different from that of the non-inflammatory or simple form. 
 But there are numerous transition types in which a sharp line 
 of distinction cannot be drawn. Furthermore, simple glau- 
 coma may change to acute or chronic inflanunatory glaucoma. 
 
 ACUTE INFIiAMlSATOBT GLAUCOMA 
 
 Symptoms. — The affection can be divided into three stages: . 
 1, the prodromal stage, 2, the stage of active glaucoma, and 
 3, the stage of absolute glaucoma. To these we may add a 
 fourth stage, the stage of degeneration. 
 
 The Prodromal Stage. — This stage is present in most in- 
 stances; it may, however, be absent. There will be some 
 diminution in the acuteness of vision — the sight appears to be 
 obscured by fog. A ring of rainbow tints will be seen around 
 lights; the cornea, especially at its centre, will, upon careful 
 inspection, be found slightly clouded; this condition (oedema) 
 is the cause of the preceding symptoms. There will be a feel- 
 ing of dulness or slight pain in the eye and head. The ante- 
 rior chamber is rather shallow, the pupil somewhat dilated, 
 often oval, and sluggish in reaction. The tension of the globe 
 is increased. There is often slight circumcorneal injection. 
 
 These symptoms last for a number of hours and then dis- 
 appear entirely; the eye returns to a normal condition, except 
 that there is a diminution in the power of accommodation, so 
 that the patient requires stronger glasses than are natural at 
 his age. Hence a rapid increase of presbyopia should always 
 excite suspicion of glaucoma. Such prodromal attacks are 
 often excited by insomnia, worry, emotional excitement, or 
 some condition which causes venous congestion, and some- 
 times by overeating, indigestion, or the local use of atropine. 
 They are in many cases relieved by sleep. At first the attacks 
 are separated by intervals of weeks or months, but they soon 
 become more frequent. 
 
PLATE XV 
 
 Fig. 183. — Aciitf Inflammatory Glaucoma. 
 
 Fig. 184.— The Fundus in Chronic Glaucoma. 
 
ACUTE INFLAMMATORY GLAUCOMA 201 
 
 This stage lasts a number of weeks or months, sometimes 
 several years ; then the disease suddenly passes into the second 
 stage. 
 
 The Stage of Active Glaucoma ("Glaucomatous Attack "). 
 
 ^The sudden onset which characterizes this stage may be due 
 to one of the exciting causes which bring on the prodromal 
 attacks. There are rapid failure of sight, contraction of the 
 visual field, especially on the nasal side (Fig. 188), and severe 
 pain in the eye, radiating along the branches of the fifth nerve 
 and causing violent headache; this pain is sometimes so severe 
 that it occasions nausea, vomiting, general depression, and 
 febrile disturbances, such attacks having been mistaken for 
 " bilious attacks." 
 
 Objective examination reveals marked increase in tension. 
 The lids are swollen and oedematous. The ocular conjunctiva 
 is markedly congested and chemotic. The cornea is clouded 
 or steamy (due to csdema), often presents punctate opacities, 
 and is insensitive (from pressure upon nerve filaments) ; there 
 is pronounced circumcorneal injection of a dark red color; the 
 episcleral veins are prominent (Fig. 183, Plate XV). The 
 anterior chamber is shallow, the aqueous sometimes turbid. 
 The pupil is dilated, oval, immobile, and often presents a 
 greenish reflex. The iris is congested, discolored, and dull. 
 The lens and the periphery of the iris are pushed forward. 
 No details of the fundus can be seen with the ophthalmo- 
 scope, on account of the clouding of the media. 
 
 In many cases in the course of a few days or weeks a decided 
 improvement takes place. The pain subsides, congestion and 
 oedema of lids and conjunctiva disappear, the cornea clears up, 
 and sight improves. But the eye does not return to a perfectly 
 normal condition; it is left in a condition known as the 
 
 Glaucomatous State. — Vision is not so acute as it was be- 
 fore the attack, and the visual field is somewhat contracted, 
 especially on the nasal side. The pupil remains dilated, oval, 
 and sluggish, the iris discolored, the anterior chamber shallow, 
 tension increased, and there is more or less circumcorneal in- 
 jection; the power of accommodation is diminished. 
 
 After a period of quiescence of variable length, another 
 
202 
 
 GLAUCOMA 
 
 attack occurs similar to the first, and this is succeeded by 
 others; each attack causes greater reduction in sight. 
 
 After a while, the increased tension causes excavation of the 
 optic-nerve disc (Fig. 187) recognizable with the ophthalmo- 
 scope in the intervals between attacks, when the media are 
 clear. The lamina cribrosa, the portion of the sclera which is 
 perforated by the optic-nerve fibres, is most yielding and 
 
 Fig. 185. Fig. 186. Fig. 187. 
 
 Figs. 185, 186, 187. — Ophthalmoscopic Appearances and Longitudinal Section of the 
 Optic-Nerve Disc. Fig. 185, Normal Disc; Fig. 186, Disc in Optic-Nerve Atrophy; 
 Fig. 187, Glaucomatous Excavation. 
 
 hence bulges backward with the fibres of the nerve as a result 
 of increased intraocular pressure. With the ophthalmoscope 
 a deep depression with very steep or overhanging margins is 
 seen; this is known as the glaucomatous cup or excavation 
 (Fig. 184, Plate XV). The blood-vessels bend sharply over 
 the margins of this excavation and often appear interrupted in 
 this situation, being again seen, more or less faintly, at the 
 bottom of the depression. They are pushed over toward the 
 nasal side. The veins are distended and the arteries con- 
 tracted. There is pulsation in the veins and in the arteries at 
 the disc. Pulsation in the veins is often seen in health, but 
 arterial pulsation is always pathological, and is an important 
 symptom of glaucoma (it is also seen in certain forms of heart 
 disease); if not spontaneous, it can be produced by slight 
 pressure upon the eyeball. The optic nerve becomes atrophied 
 and the disc appears pale, or in late stages greenish or bluish. 
 The disc is often surrounded by a whitish-yellow ring {glau- 
 
ACUTE INFLAMMATORY GLAUCOMA 203 
 
 conmtous halo or ring), due to atrophy of the choroid in this 
 situation. 
 
 The Stage of Absolute Glaucoma. — With each succeeding 
 attack the diminution in vision becomes greater, until finally 
 blindness ensues; the condition is then known as absolute 
 glaucoma. There are now no inflammatory or congestive 
 symptoms, except a dark-red zone of circumcorneal injection 
 and dilated episcleral veins. The cornea remains clear or 
 slightly clouded, and often more or less insensitive. The 
 pupil is widely dilated, immobile, and often presents a greenish 
 reflex. The iris is atrophied, narrow, gray, with a border of 
 dark pigment. The anterior chamber is shallow. Tension 
 is markedly increased. The fundus presents a deep excavation 
 of the disc, the glaucomatous ring, and atrophy of the optic 
 nerve. Pain may disappear entirely, but frequently contin- 
 ues, and the patient suffers from severe attacks at intervals. 
 
 The Stage of Degeneration. — ^After absolute glaucoma has 
 lasted a variable length of time, the eyeball is apt to degen- 
 erate. The cornea becomes more or less opaque, and fre- 
 quently covered by deposits or vesicles. The sclera bulges 
 and bluish-black staphylomata appear between the cornea 
 and the equator. Detachment of the retina often takes place. 
 The lens is apt to become cataractous. The patient may 
 experience subjective sensations of light. The final result is 
 that the eyeball either softens, shrinks, and atrophies, or else 
 there are ulceration and perforation of the cornea, followed by 
 iridocyclitis, with subsequent atrophy of the eyeball, or 
 panophthalmitis and phthisis bulbi. 
 
 Glaucoma Fulminans is the name given to a form, of rare 
 occurrence, in which very violent symptoms of inflammation 
 develop suddenly, and in which blindness may ensue in a few 
 hours, unless proper treatment be instituted. 
 
 CHBONIO INFLAMMATOBY GLAUCOMA 
 
 This form of glaucoma is much more common than the acute 
 variety just described. Its symptoms resemble those of the 
 acute variety, but are less intense and more gradual in their 
 onset. Very often the prodromal stage passes uninterruptedly 
 
204 GLAUCOMA 
 
 into the stage of inflammation, and. there is no succession of 
 
 attacks. The ocular conjunctiva is congested and dusky, the 
 
 episcleral veins being very prominent; there is circumcorneal 
 
 injection of a dark-red color; the cornea is steamy and more 
 
 or less insensitive; the anterior chamber is shallow, and the 
 
 lens and iris are pushed forward; the pupil is dilated, oval, and 
 
 rigid, surrounded by the discolored, narrow, and atrophic iris, 
 
 and presents a greenish reflex. There is pain, but this is not 
 
 so intense as in the acute form. There are gradual loss of 
 
 sight and progressive limitation of the. field, especially on the 
 
 nasal side. After having lasted a suflScient length of time, 
 
 the ophthalmoscope reveals the same changes in the fundus 
 
 which are found in acute cases. 
 
 The chronic form has the same termination as the acute: 
 
 absolute glaucoma and finally degeneration of the eyeball. 
 
 In many cases, no sharp line of differentiation can be drawn 
 
 between the acute and the chronic forms of inflammatory 
 
 glaucoma. 
 
 SIISFLE GLAXJCOMA 
 
 In simple glaucoma (Chronic Non-Inflammatory Glau- 
 coma), there is an absence of any marked external symptoms; 
 there are no inflammatory attacks and no pain. 
 
 The diagnosis is made by noting the increase of tension, and 
 by the picture presented when the ophthalmoscope is used. 
 
 This form develops very gradually, and may have lasted 
 some time before the patient becomes aware of the existence 
 of any abnormal condition. The eye may appear perfectly 
 normal externally, or there may be slight circumcorneal infec- 
 tion and moderate dilatation of the episcleral veins. The 
 pupil is slightly or moderately dilated and is sluggish. The 
 tension is elevated, often moderately; sometimes the increase 
 is not constant; with the tonometer a slight rise in tension 
 can almost always be discovered. After the disease has lasted 
 a certain length of time, the ophthalmoscope shows glauco- 
 matous excavation (Fig. 187, and Fig. 184, Plate XV), atrophy 
 of the optic nerve, and the circumpapillary ring of choroidal 
 atrophy, the degree of change depending upon the duration 
 of the process. 
 
SIMPLE GLAUCOMA 
 
 205 
 
 There may be periods when the patient complains of symp- 
 toms like those in the prodromal stage : Foggy vision, colored 
 halos around artificial lights, and diminished accommodation. 
 There are gradual loss of sight, premature presbyopia, and pro- 
 gressive contraction of the visual 
 field, especially on .the nasal side 
 (Fig. 188), the reduction in the ex- 
 tent of the color-fields correspond- 
 ing to that of the form-field. Scoto- 
 mata are common; they may be cen- 
 tral, paracentral, or peripheral; a very 
 characteristic defect is often found 
 directly continuous with the normal 
 blind spot and therefore causing an 
 enlargement of this area. Central 
 vision is the last portion to be lost. 
 On this account the patient may be able to read, and yet 
 the field of vision be quite limited. 
 
 The course of simple glaucoma is very insidious and its 
 duration is years; if unchecked, it terminates in blindness. 
 Sometimes this form gradually changes into the chronic in- 
 flammatory type, and then goes through the stages of the 
 latter disease. 
 
 Fig. 188.— The Field of Vi- 
 sion in Glaucoma. Periph- 
 eral Contraction, especially 
 on the Nasal Side. 
 
 Occurrence and Etiology. — Glaucoma is a disease of ad- 
 vanced life, occurring generally between forty and seventy, 
 infrequently before this period. The inflammatory form 
 attacks women more often than men, the simple type occurs 
 equally in both sexes. It usually involves both eyes, the sec- 
 ond eye generally becoming affected months or years after the 
 first. The exact cause of glaucoma is unknown. There are a 
 number of predisposing conditions: It occurs much more fre- 
 quently in Jews than among Christians. There is not uncom- 
 monly a history of heredity. Arteriosclerosis and cardiac 
 disease, chronic constipation, and the gouty and rheumatic 
 diatheses are predisposing factors. A disposition toward in- 
 flammatory glaucoma exists in hyperopic eyes (myopic eyes 
 are particularly exempt) as well as in small eyeballs with large 
 
206 
 
 GLAUCOMA 
 
 lenses, and in those in which the cornea is of small size. The 
 exciting causes may be the following: Emotions especially of a 
 depressing character, insomnia, worry, injudicious use of atro- 
 pine, overuse of ametropic eyes, insufficient food, overeating, 
 indigestion, dissipation, various fevers especially influenza, 
 and any condition which produces venous congestion. 
 
 Mode of Origin and Pathology. — All the symptoms of glau- 
 coma can be explained by increase in intraocular -pressure and 
 venous congestion. But the cause of this increase in tension 
 
 has not yet been de- 
 termined; none of the 
 many theories has been 
 adequate to explain 
 the occurrence of this 
 disease in every case. 
 The increased tension 
 must depend upon a 
 disturbed relationship 
 between intraocular se- 
 cretion and excretion. 
 The older theories as- 
 sumed the existence 
 of hypersecretion produced in various ways; these views have 
 been discarded. It is at the present time considered more 
 probable that the disease is due to some interference with ex- 
 cretion (retention) . The obstruction to the escape of the in- 
 traocular liquids is thought to be situated at the angle of 
 the anterior chamber (iris angle). It is believed that this 
 angle (Figs. 181, 189, 190) is obliterated by pressure of the 
 peripheral portion of the iris against the sclerocorneal junc- 
 tion (ligamentum pectinatum) by the congested and swol- 
 len ciliary processes; later there is an adhesive inflammation 
 between these opposed surfaces through proliferation of the 
 endothelium of Descemet's membrane and of the iris. As 
 already explained, this iris angle forms the principal exit for 
 intraocular fluids, and when it is blocked, retention takes 
 place. An additional causative factor is supposed to be the 
 narrowing of the drcumlental space (between the margin of 
 
 Fig. 189. — ^Angle of the 
 Anterior Chamber in 
 the Normal Eye. 
 
 Fig. 190.— Angle of the 
 Anterior Chamber in 
 Recent Inflammatory 
 Glaucoma. 
 
PATHOLOGY OF GLAUCOMA 207 
 
 the lens and the ciliary body) in eyes predisposed to glau- 
 coma. This area serves for the passage of the Ijonph which 
 is secreted by the choroid and part of that produced by the 
 ciliary body; it is encroached upon by the increased size of 
 the lens with advancing age and by the comparatively large 
 size of the ciliary body and the smaller size of the eyeball 
 in general, in hyperopes. This embarrassment in the com- 
 munication between vitreous and aqueous chambers would 
 cause venous congestion, subsequent swelling of the ciliary 
 body, overdistention of the vitreous, with the result of push- 
 ing the periphery of the iris against^he sclerocorneal junction, 
 thus blocking up the iris angle. But no explanation of the pro- 
 duction of glaucoma satisfactorily fits all types of the disease; 
 probably they are not all developed in the same manner. 
 
 Differential Diagnosis. — The inflammatory form of glau- 
 coma has been mistaken for iritis and conjunctivitis; the use 
 of atropine in such cases has caused great mischief. The 
 dilated pupil, increase in tension, shallow anterior chamber, 
 steamy cornea, as well as the subjective symptoms ought to 
 be sufficient to differentiate (see tables on p. 167). The 
 peculiar greenish pupillary reflex has been diagnosed as cata- 
 ract, and thus valuable time has been lost in awaiting the 
 ripening of this supposed lens change. In acute cases, the 
 violent headache and general constitutional symptoms have 
 misled the medical practitioner, and been responsible for the 
 diagnosis of some general febrile disease, at a time when active 
 ocular treatment was urgent. 
 
 Simple glaucoma is sometimes mistaken for simple optic- 
 nerve atrophy. In the latter case, there will be absence of 
 increased tension; the excavation of the disc is shallow and 
 gradual (Figs. 186, 187, and Plates XV and XXI); there is 
 apt to be greater diminution in central vision; the form fields 
 present more uniform contraction; the color fields show 
 greater peripheric loss, while in simple glaucoma they cor- 
 respond in extent to the form field; and there is an absence 
 of scotoma directly continuous with the blind spot. There 
 are, however, instances in which the differential diagnosis 
 between these two affections is not easy, particularly when 
 
208 GLAUCOMA 
 
 the increase of tension is very slight or happens to be tem- 
 porarily absent. 
 
 Prognosis is bad in every case, if proper treatment is not 
 instituted; vision becomes worse, more or less rapidly, but 
 progressively, until complete blindness results. With correct 
 treatment the prognosis is more favorable; it depends upon 
 the type of disease, being most favorable in acute cases de- 
 tected and treated early; in chronic forms the chances are 
 influenced by the amount of degenerative change which exists 
 when the patient first applies for treatment. 
 
 Treatment. — (1) Operative, (2) non-operative, and (3) 
 general. 
 
 Operative Treatment consists of iridectomy (the excision of a 
 portion of the iris), sclerotomy (an incision through the sclera), 
 and various procedures having for their object the production 
 of a cystoid scar or filtering cicatrix. 
 
 Operative intervention is, in general terms, the most satis- 
 factory treatment for glaucoma, certainly the inflammatory 
 type, and probably also for the simple form, especially when 
 increased tension is at all prominent. Until recently, iridec- 
 tomy was the operation of choice and the one resorted to 
 almost exclusively. Since a few years, however, various pro- 
 cedures having for their object the production of a filtering 
 cicatrix in the sclera, just beyond the limbus, have been used 
 extensively. The most prominent of these are Lagrange's 
 operation (sclerectomy combined with iridectomy), Herbert's 
 operation (subconjunctival sclerotomy combined with iridec- 
 tomy) and Elliot's operation {trephining the sclera combined 
 with iridectomy), described on p. 216; of these the last has 
 been most favored. These operations have been resorted to 
 frequently for all forms of glaucoma excepting the acute in- 
 flammatory type in which most operators still prefer iridec- 
 tomy. But, notwithstanding the conceded usefulness of these 
 procedures, iridectomy still remains the most popular opera- 
 tion for glaucoma, especially since cataract and late infec- 
 tions of the eyeball have occurred in a sufficient proportion 
 of cases to constitute a handicap which has to be con- 
 sidered; these late infections are made possible by the thin 
 
TREATMENT OF GLAUCOMA 209 
 
 barrier between the conjunctival sac and the interior of 
 the eyeball existing at the seat of the scleral defect. 
 
 Non-Operative Treatment consists chiefly in the local use of 
 the miotics — eserine salicylate (j to | per cent.), and pilocar- 
 pine muriate (1 to 2 per cent.). The former has the stronger 
 action, but produces more irritation, especially when used for 
 a long time. These solutions are instilled two or three times 
 a day or oftener; they act by drawing the iris away from the 
 angle of the anterior chamber; hence, they are of no value 
 after the iris has become atrophic and is incapable of con- 
 tracting, a condition observed in old cases of glaucoma. They 
 are often merely palliative measures of temporary advantage. 
 They may be used in the prodromal stage to cut short the 
 attack, or at other times, if for any reason iridectomy is 
 inadvisable, cannot be performed, or the patient refuses an 
 operation. They are also useful in acute inflammatory attacks 
 to alleviate pain, reduce tension, diminish cloudiness of the 
 media and increase the depth of the anterior chamber, thus 
 rendering iridectomy easier of execution. There are many 
 ophthalmologists who rely upon miotics, in preference to 
 operation, in simple glaucoma in which there is but little 
 increase of tension. 
 
 During an acute glaucomatous attack, in addition to frequent 
 instillations of eserine and pilocarpine, warm, moist com- 
 presses are applied, and several leeches to the temple are of 
 value; the patient is quieted and pain relieved by morphine 
 and lafge doses of sodium salicylate. Dionine also acts well. 
 
 Massage of the eyeball, applied gently to the closed lids, 
 may be used with advantage in simple and in chronic forms. 
 
 General Treatment comprises rest, sweating, proper and 
 sufficient food, saHcylate of sodium, relief of constipation, 
 correction of ametropia, avoidance of excess in eating, drink- 
 ing, and Ikte hours, the induction of sleep, and the relief of 
 any of the other conditions which have been mentioned as 
 predisposing to glaucoma. Nitroglycerine is useful if there 
 exists high blood-pressure. 
 
 Iridectomy. — The Instruments Required include an eye 
 speculum (Fig. 191), a fixation forceps (Fig. 192), a bent and 
 
210 
 
 GLAUCOMA 
 
 a straight lance-shaped knife (Fig. 193) or a Graefe cataract 
 knife (Fig. 194), a curved iris forceps (Fig. 195), curved iris 
 
 Fig. 191.— Eye 
 Speculum. 
 
 Fig. 198. — Iris Repositor. 
 Fig. 199.— rri3 Hook. 
 
 Fig. 197. — De Wecker's Iris Scissors. 
 Figs. 191-199. — Instruments Required tor Iridectomy. 
 
 scissors (Fig. 196) or De Wecker's iris scissors (Fig. 197), an 
 iris repositor (Fig. 198), and a blunt iris hook (Fig. 199). 
 
IRIDECTOMY 
 
 211 
 
 The operation will be described as performed for glaucoma. 
 Cocaine or holocain may be employed in simple glaucoma and 
 in some cases of inflammatory glaucoma; but in nervous and 
 unruly individuals, as well as in many instances of the inflam- 
 matory forms of glaucoma, general anaesthesia is necessary, 
 since the tense and congested tissues do not readily absorb 
 local anaesthetics, and the seizing and cutting of the iris are 
 painful. A few drops of a 4 per cent, solution of cocaine 
 injected subconjunctivally, just below the cornea, increases 
 the local anaesthesia. 
 
 Operation. — Iridectomy for glaucoma is usually done up- 
 ivard, so that the defect is covered by the upper lid, thus 
 limiting troublesome optical effects of the coloboma. The 
 
 Fig. 200. 
 
 -Section of the Sclera in Iridec- 
 tomy. 
 
 Fig. 201. — Division of the Iris in Iridec- 
 tomy. 
 
 operator, standing behind the patient's head, introduces the 
 speculum, obtains a firm grasp of the conjunctiva just below 
 the lower margin of the cornea, directs the patient to look 
 down, and thrusts the lance-shaped knife into the sclera above 
 the cornea, entering 1 mm. behind the limbus (Figs. 200 and 
 202); the knife is directed perpendicularly until its point is 
 seen in the anterior chamlDcr, and then pushed forward in a 
 direction parallel to the plane of the iris until the scleral 
 wound is of sufficient size (6 to 8 mm.) ; care is taken not to 
 pass between the layers of the cornea, nor to wound the iris 
 or lens capsule. The knife should be withdrawn sloivly so that 
 the reduction in tension is not too sudden, which might cause 
 
212 
 
 GLAUCOMA 
 
 intraocular hemorrhage and other injury; its point is directed 
 toward the cornea without scraping its posterior surface. 
 When there are considerable increase in tension and a very 
 
 Fig. 202. — Iridectomy; 
 Scleral Section. 
 
 Fig. 203. — Iridectomy; 
 Grasping the Iris. 
 
 Fig. 204. — Iridectomy; 
 Excision of the Piece 
 of Iris. 
 
 shallow anterior chamber, the Graefe knife is often preferred 
 for the scleral incision; it is made to enter 1 mm. behind the 
 limbus, at about the junction of the lower five-sixths with the 
 upper sixth, passes across the anterior chamber (great care 
 being exercised not to wound the iris or lens capsule), land 
 emerges at a corresponding point 1 mm. behind the limbus on 
 the opposite side, the incision being completed by to-and-fro 
 movements. 
 
 An assistant now takes the fixation forceps. The operator 
 passes the closed iris forceps through the scleral incision to 
 the pupillary margin (Fig. 203), opens the instrument, seizes 
 the pupillary border of the iris between its branches, draws 
 the iris out of the wound, and cuts it off close to the cornea, 
 the blades of the iris scissors being parallel to the wound (Figs. 
 201 and 204). The piece of iris removed (Fig. 205) should 
 comprise the entire width including the ciliary attachment. 
 
 In iridectomy performed on an aphakial eye (after cataract 
 operations), it is difficult to grasp the iris with forceps; in 
 such cases the iris is drawn jout with the blunt hook (Fig. 199). 
 
 The resulting coloboma must be large, cleanly cut, and the 
 pupillary margin of the iris must return to its natural position 
 
IRIDECTOMY 
 
 213 
 
 Fig. 205. 
 
 Pig. 206. 
 
 Fig. 207. 
 
 producing a keyhole-shaped pupil (Fig. 205). No iris tissue 
 must be left in the wound, since this causes subsequent irri- 
 tation and complications. Proper replacement of the iris is 
 accomplished by strok- 
 ing the wound with the 
 iris repositor (Fig. 198), 
 and by passing the lat- 
 ter into the incision and 
 freeing the angles. 
 
 Hemorrhage into the ^^°- 205.— iridectomy in Glaucoma. Fig. 206, 
 , . 11 • Iridectomy Preceding Cataract Extraction. Fig. 
 
 anterior chamber is 207, iridectomy tor Artificial Pupil. 
 
 common; the blood is 
 
 usually absorbed in a few days; it is not wise to make too 
 great efforts to dislodge the blood, since undue pressure 
 may cause the lens to become cataractous. Sometimes 
 retinal hemorrhages occur and are subsequently absorbed, 
 doing no damage unless they involve the macular region. 
 
 Both eyes are bandaged, and the patient is kept quiet 
 in bed. After a day, the unoperated eye may be left uncov- 
 ered. Recovery is smooth in most instances; in some cases 
 the anterior chamber is not re-formed for several days. Cys- 
 toid cicatrix sometimes results — a condition which is not 
 objectionable and is thought to facilitate filtration. 
 
 Results of Iridectomy in Glaucoma. — The manner in which 
 iridectomy relieves glaucoma is not definitely known. The 
 earlier the operation is performed, the more sight is pre- 
 served. Hence it is advisable to do the operation as soon as 
 possible. The best time is during the prodromal stage, in the 
 interval between attacks. In inflammatory cases, during the 
 stage of acute glaucoma, the operation is very difficult on 
 account of the severe congestion and the shallowness of the 
 anterior chamber; under such circumstances, it is usually 
 advisable to instil eserine or pilocarpine at frequent intervals 
 and to treat the patient in the manner already described for 
 a day or two, so as to reduce tension and increase the depth 
 of the anterior chamber, and then to operate; but if these 
 miotics do not act, the operation must be performed without 
 further delay. 
 
214 GLAUCOMA 
 
 The most favorable results of iridectomy are seen in cases 
 of acute inflammatory glaucoma; in such instances pain and in- 
 flammatory symptoms subside rapidly and sight returns up to 
 the degree possessed before the onset of the attack. Further- 
 more, the results are generally lasting. Exceptionally the 
 effects of an iridectomy are disappointing or temporary, and 
 the operation must be repeated opposite to or at the side of 
 the first, or sclerotomy performed. In rare cases operation 
 has no effect upon the course of acute inflammatory glau- 
 coma, and the disease progresses until blindness ensues. 
 
 In chronic inflammatory glaucoma, the results of iridectomy 
 are favorable, but not so brilliant as in acute cases. The 
 operation relieves the pain and inflammatory symptoms, and 
 the media again become clear; but since the disease has 
 already caused permanent changes in the disc and optic 
 nerve, the restoration of sight is limited. But the progress 
 of the disease is generally checked, though sometimes a second 
 operation must be performed. In a certain nmnber of cases, 
 however, there is progressive diminution in sight notwith- 
 standing the operative intervention. 
 
 In simple glaucoma iridectomy is also indicated, but its 
 results are less marked and less permanent than in the inflam- 
 matory variety. The most that we can expect from the oper- 
 ation is that the acuteness of vision prevailing at that time 
 will be preserved or slightly increased, and that the progress 
 of the disease will be arrested. This happens in about one- 
 half of the cases. In the other half the results are not so 
 favorable. In some of these, the effects of the operation are 
 only temporary and the iridectomy has to be repeated; in 
 others, the disease progresses after a shorter or longer interval 
 of arrest, and blindness finally ensues. In a very small pro- 
 portion, the operation has an unfavorable effect upon the 
 disease; violent inflammatory symptoms appear immediately 
 of soon after the operation and the eye rapidly becomes blind; 
 such cases are known as malignant glaucoma. 
 
 In absolute glaucoma, enucleation is often indicated for the 
 relief of severe pain. 
 
 Indications for Iridectomy. — Besides (1) glaucoma, the 
 
IRIDECTOMY 215 
 
 operation is indicated in (2) some cases of chronic and recur- 
 rent iritis and iridocyclitis; (3) complete circular sjTiechia; 
 (4) partial corneal staphyloma; (5) tumors and foreign bodies 
 in the iris; (6) recent prolapse of the iris; (7) as a part of the 
 operation of extraction of cataract — here the coloboma should 
 be smaller than in glaucoma (Fig. 206) ; (8) as a means of im- 
 proving sight (artificial pupil, optical iridectomy) in central 
 opacities of the cornea and lens, occlusion of the pupil, and 
 keratoconus. 
 
 Optical Iridectomy: A small incision (3 to 4 mm.) is made 
 in the cornea, 2 mm. from the limbus, the iris drawn out with 
 the iris forceps (Fig. 195) or the blunt hook (Fig. 199), and 
 its pupillary portion excised, making as small a coloboma as 
 answers the purpose (Fig. 207). The best position for the 
 artificial pupil is downward and inward; but when there is a 
 corneal opacity, the site must correspond to the most trans- 
 parent portion of the cornea. The effects of optical iridec- 
 tomy are often disappointing; hence, before operating,, it is 
 well to dilate the pupil and, by applying a stenopseic slit held 
 in different positions, to ascertain whether there is an im- 
 provement in sight under these circumstances. 
 
 Sclerotomy (Incision Through the Sclera) is sometimes per- 
 formed for the cure of glaucoma, but it is considered inferior 
 to iridectomy. It may, however, be a useful procedure in 
 cases in which iridectomy cannot be satisfactorily performed, 
 or in which a relapse occurs after iridectomy has been done 
 once or twice. The incision in the sclera is made in two 
 situations: in front of the iris (anterior sclerotomy), and be- 
 hind the ciliary body (posterior sclerotomy). 
 
 Anterior Sclerotomy: Puncture and counterpuncture are 
 made with a Graefe knife, 1 mm. behind the limbus, similar 
 to those made in cataract extraction except that the corneal 
 flap is but 2 mm. high; the middle third is, however, left un- 
 cut and forms a bridge connecting sclera and cornea. 
 
 Posterior Sclerotomy (Scleral Puncture) : An incision (5 mm. 
 deep) is made through the sclera into the vitreous with a 
 Graefe knife, between the external and inferior recti muscles, 
 10 mm. from the corneal margin, the point being directed 
 
216 GLAUCOMA 
 
 toward the centre of the globe; care should be taken to select 
 a spot free from larger blood-vessels; before withdrawing the 
 Imife it is turned slightly on its axis so as to widen the punc- 
 ture. This operation is employed in hemorrhagic glaucoma, 
 in detachment of the retina (in which case the puncture is 
 made over the separation), and as a preliminary step in the 
 removal of foreign bodies from the vitreous. An additional 
 indication is for the purpose of lowering the tension and 
 increasing the depth of the anterior chamber in very hard 
 glaucomatous eyes, thus facilitating subsequent iridectomy. 
 Filtering Cicatrix Operations. — Disappointment with iri- 
 dectomy in chronic inflammatory and simple glaucoma has 
 prompted operations having for their object the formation of 
 a permanent, filtering cicatrix. Most promising and popular 
 of these are Elliot's (trephining) and Lagrange's (sclerectomy 
 with iridectomy). Though still on trial, these procedures 
 often succeed in permanently reducing tension and, especially 
 Elliot's operation, are at present very popular. 
 
 Elliot's Operation (Trephining of the Sclera). — ^A large tri- 
 angular conjunctival flap is dissected from above the cornea 
 
 concentric with the limbus, the 
 connective tissue at the angles 
 of the flap being left intact. The 
 limbus having been clearly de- 
 fined, the area over which we 
 are about to trephine must be 
 carefully cleansed of all tags of 
 
 F.G. 208.-Ellio^^.^Operation for j^^^^ ^jgg^g_ ^^^ ^^^ ^^^_ 
 
 junctival flap is drawn gently 
 downward by traction with closed forceps and the cornea 
 split with closed scissors-points by means of a number of 
 short lateral strokes along the line just beyond the reflection 
 of the flap (Fig. 208). As the dissection proceeds the 
 deeper layers of the split cornea can be seen as a dark 
 crescentic area. Having prepared sufficient space, the 
 trephine (1.5 or 2 mm. in diameter) is applied (Fig. 209), 
 and a hole made as far forward as possible, the blade being 
 made to cut out the corneal edge first. As soon as the tre- 
 
SCLERAL TREPHINING 217 
 
 phine has cut its way through, the disc, hinged on its scleral 
 side, will be pushed upward and backward by a bead of 
 iris prolapsing through the corneal side of the opening. 
 Grasping both disc and bead of iris in one grip of 
 the forceps, these are excised together with a sin- 
 gle snip of the scissors. The iris must be re- 
 placed and no tags of uvea left in the wound; to 
 insure this we use a small irrigator and direct a 
 stream of saline solution into the anterior cham- 
 ber. The conjunctival flap is replaced, no sutures 
 being used unless it shows a tendency to become 
 displaced. Both eyes are bandaged. On the third 
 day, if the tension is down, 1 per cent, atropine is in- 
 stilled, imless the pupil is widely dilated and active. 
 
 Lagrange's Operation (Sclerectomy combined 
 with Iridectomy). — In addition to the instruments 
 used for iridectomy, small sharp scissors with a fig. 209.— 
 marked curve on the flat are needed. With a T^^p^'^^ 
 Graefe knife the sclera is punctured 1 mm. from 
 the limbus and counterpunctm'ed at a corresponding 
 point 7 mm. removed. The incision is made in the iris angle, 
 and at its termination the edge of the knife is directed back- 
 ward so as to bevel the sclera, then continuing so as to make 
 a 5 mm. conjunctival flap. The latter is drawn forward, thus 
 tilting the edge of the scleral flap upward, and a piece of the 
 latter exsected with the curved scissors. Iridectomy is per- 
 formed, and finally the scleral defect is covered by the con- 
 junctival flap. 
 
 Cyclodialysis (Heine's Operation) consists of an incision 
 in the sclera 8 mm. behind limbus, separating ciliary body 
 from overlying sclera and breaking through the pectinate 
 ligament, thus detaching a portion of the periphery of the 
 iris. The artificial communication between anterior chamber 
 and suprachoroidal space thus made forms a new channel for 
 the escape of aqueous. This procedure may be done in ad- 
 vanced glaucoma or when other operations have failed, but 
 cannot ordinarily be regarded as a substitute for iridectomy 
 or other operations for glaucoma. 
 
218 GLAUCOMA 
 
 Exsection of the Superior Cervical Ganglion of the Sympa- 
 thetic has been abandoned as a substitute for iridectomy, 
 since its results were unsatisfactory; it may occasionally be 
 considered when all other means seem inadvisable or have 
 failed. 
 
 Secondary Glaucoma is the name given to cases of in- 
 creased tension and other symptoms of glaucoma developing 
 as a result of some other ocular disease or injury. The clini- 
 cal picture varies with the disease which it complicates. The 
 course is either acute or chronic and the consequences are the 
 same as in primary glaucoma. 
 
 The ocular affections which are most frequently followed 
 by secondary glaucoma are: Ulcers or wounds of the cornea 
 with prolapse of iris, corneal cicatrices and staphylomata with 
 incarceration of the iris, iridocyclitis, uveitis and choroiditis, 
 total posterior (ring) synechia, dislocation of the lens, trau- 
 matic cataract (swelling of the lens), the operations of extrac- 
 tion, needling of the lens and discission of secondary cataract, 
 intraocular tumors, and foreign bodies in the eye. In old 
 persons with arteriosclerosis, a form of secondary glaucoma 
 with retinal hemorrhages is seen, and is laiown as hemorrhagic 
 glaucoma. 
 
 Treatment is similar, in general, to that required for primary 
 glaucoma, modified by the nature of the cause and its re- 
 moval. Hemorrhagic glaucoma does not respond favorably 
 to treatment; iridectomy is liable to be followed by an aggra- 
 vation of symptoms; posterior sclerotomy may be of service; 
 the other agents used in glaucoma may be tried, but are 
 often of no benefit. 
 
 Congenital Glaucoma (Hydrophthalmos, Buphthalmos, 
 Keratoglobus) is a disease of early childhood, either congenital 
 or developing in infancy and usually involving both eyes. 
 There is an increase of intraocular tension which, on account 
 of the yielding character of the sclera at this period of life, 
 causes marked enlargement of the eyeball. The cornea is en- 
 larged and bulging, and either remains clear or becomes 
 clouded; the anterior chamber is very deep; the pupil is 
 dilated, and the iris atrophied and tremulous; the sclera is 
 
CONGENITAL GLAUCOMA 219 
 
 thinned and bluish, owing to the uveal pigment showing 
 through; the disc is deeply excavated. The disease progresses 
 slowly. Though in some cases it comes to a spontaneous stop 
 with the preservation of moderately good vision, it generally 
 leads to blindness. The prognosis is unfavorable. As a rule 
 treatment is of little benefit; since, however, some cases have 
 been benefited by iridectomy, sclerotomy, repeated paracen- 
 tesis of the anterior chamber, and miotics, these measures 
 should be tried. 
 
CHAPTER XVI 
 
 DISEASES OF THE VITREOUS 
 
 Anatomy. — The vitreous is a transparent, colorless mass, of soft 
 gelatinous consistence, which fills the posterior cavity of the eyeball be- 
 hind the lens. Its outer surface presents a thin, structureless covering, 
 the hyaloid membrane. The vitreous is traversed from the optic disc to 
 the posterior capsule of the lens by a canal, the hyaloid canal, serving 
 as a lymph channel in the developed eye, and containing the hyaloid 
 artery during fcetal life. In structure the vitreous consists of a trans- 
 parent network, in the meshes of which are clear liquid and round and 
 branching cells, probably emigrated white blood-corpuscles. The vit- 
 reous has no blood-vessels, but receives its nourishment from the sur- 
 rounding tissues: the choroid, ciliary body, and retina. 
 
 Persistent Hyaloid Artery. — The hyaloid artery usually disappears 
 entirely during the later months of gestation. Occasionally a gi'eater 
 or lesser remnant persists during life. This can be seen with the oph- 
 thalmoscope, as a grayish cord or thread, which arises from the optic 
 disc and stretches into the vitreous, with a free extremity or occasion- 
 ally attached to the posterior pole of the lens; sometimes there is an ac- 
 companying opacity of the posterior portion of the lens. Rarely, the 
 hyaloid canal is abnormally dense and is visible as a grayish, tubular 
 cord extending from disc to lens. 
 
 The principal affections of the vitreous are fluidity, opaci- 
 ties, muscse volitantes, hemorrhages, abscess, and foreign 
 bodies. Since this structure is devoid of blood-vessels, pri- 
 mary inflammation does not occur; hence the term hyalitis, 
 sometimes used, is incorrect. 
 
 Fluidity of the Vitreous (Synchysis) is a liquid alter- 
 ation in consistency which, when limited in degree, may be 
 merely a senile change; but when pronounced, it is due to de- 
 generation of this structure dependent upon disease of neigh- 
 boring parts: choroid, ciliary body and retina, and found often 
 in myopia of high degree. When opacities are present, these 
 are observed to move freely in such fluid vitreous; there is 
 often diminished tension of the eyeball, tremulousness of the 
 iris, and sometimes a predisposition to detachment of the 
 
 220 
 
FLUIDITY OF THE VITREOUS 221 
 
 retina. Occasionally small glistening opacities are found in 
 degenerated eyeballs and in some which are normal in other 
 respects, especially in old persons; they fall in a silvery 
 shower when the eyeball is moved; they are usually crystals 
 of cholesterin in a fluid vitreous; the appearance is known as 
 Synchysis Scintillans. 
 
 Opacities of the Vitreous are quite common. They 
 may occur as a consequence of changes in the vitreous itself, 
 but usually they are the result of disease or of hemorrhages 
 from the neighboring structures — ciliary body, choroid, and 
 retina. They may be fixed or mobile and vary in number, 
 shape, and size: (1) A diffuse cloud or a dust-like haziness 
 often accompanies cyclitis, choroiditis, iridochoroiditis, and 
 retinitis; when dust-like it is suggestive of syphilitic origin. 
 (2) The opacities may occur in the form of dots, flakes, 
 threads, or membranous masses, the result of exudations or 
 hemorrhages. (3) Sometimes extensive membranes are met 
 with, which are attached to the retina and provided with 
 blood-vessels; these are supposed to result from chronic retinal 
 disease, called Retinitis Proliferans. 
 
 Etiology.- — Opacities of the vitreous are very common in 
 myopia of high degree associated with changes in the choroid; 
 they are often seen accompanying diseases of the uvea and 
 retina; they occur after injuries which have caused hemorrhage 
 from the choroid or ciliary body; they may result from certain 
 systemic diseases; and they may exist in patients in whom 
 we can find no cause and no evidence of ocular disease, espe- 
 cially in the aged. 
 
 Symptoms. — There is more or less disturbance of vision, 
 depending upon the situation, size, and density of the opac- 
 ities. The latter are most frequently movable, indicating a 
 fluid vitreous (synchysis), the result of disease of surrounding 
 parts; on this account, the visual disturbance may vary at 
 different times according to whether the opacity happens to 
 have gravitated into the line of vision, and the patient may 
 be able to move the eyeball in a certain way so as to throw 
 the opacity out of the line of sight. 
 
 Diagnosis is made with the ophthalmoscope at a distance. 
 
222 DISEASES OF THE VITREOUS 
 
 The vitreous opacities appear as dark spots upon a red 
 ground, moving with greater or lesser rapidity, depending 
 upon the consistence of the vitreous, when the eye is turned 
 in various directions. When faint, the opacities are best seen 
 with diminished illumination and. with the plane mirror. 
 They may also be examined by the direct method of ophthal- 
 moscopy, by interposing stronger and stronger convex lenses 
 in the sight-hole of the ophthalmoscope, and thus focussing 
 more and more anterior portions of the vitreous cavity. 
 
 Prognosis varies with the size, density, and nature of the 
 opacity. Syphilitic opacities and small hemorrhages fre- 
 quently clear up when treated early. Others become smaller 
 and less dense after a time. A great many are permanent. 
 
 Treatment. — Anti-syphilitic treatment is indicated in spe- 
 cific cases. In others, small doses of potassiimi iodide and 
 mercury may be of service; also other forms of iodine medica- 
 tion. Diaphoretics and cathartics are often employed. Sub- 
 conjunctival injections of physiological salt solution (0.6 per 
 cent.) may be useful. 
 
 Muscae Volitantes is the term employed for the ap- 
 pearance of spots (motes) before the eyes, without appreciable 
 structural change in the vitreous or other media. They are 
 caused by the shadows cast upon the retina by the cells 
 normally found in the vitreous, and are present in all eyes 
 under certain circumstances, such as exposure to a uniform 
 bright surface, or in looking through a microscope. They are 
 found more frequently in errors of refraction (especially my- 
 opia), and the symptom may be aggravated temporarily dur- 
 ing digestive derangements. They occur as grayish shadows, 
 which move with changes in the position of the eyes, having 
 the shape of dots or globules frequently collected into strings; 
 they may have any shape. They are annoying and some- 
 times alarm the patient, but are of no importance, and do not 
 affect the acuteness of vision. The treatment consists in 
 correcting errors of refraction, or in relieving the disturbance 
 of digestion. They often persist until the patient ceases to 
 look for them and thus forgets their existence. 
 
 Hemorrhages into the Vitreous come from the cho- 
 
HEMORRHAGES INTO THE VITREOUS 223 
 
 roidal, retinal, and ciliary body vessels and produce interference 
 with vision, the degree depending upon their size. When small, 
 they have a red color as seen with the ophthalmoscope; when 
 larger they appear as dark-red masses; and when very exten- 
 sive they fill the vitreous cavity and no red reflex can be 
 obtained with the ophthalmoscope, the pupil appearing black. 
 Smaller hemorrhages are often absorbed; larger ones are apt 
 to result in permanent membranous masses. 
 
 Hemorrhages into the vitreous occur after injuries, com- 
 plicating choroiditis and retinitis, in high myopia and in 
 glaucoma, as an example of vicarious menstruation, in 
 arteriosclerosis and other systemic disorders, such as anae- 
 mia, nephritis and diabetes, and finally spontaneously 
 from unknown cause. The exciting cause may be a strain 
 of some kind, such as a cough. 
 
 One form occurs in young adults, usually males, with im- 
 known etiology except that tuberculosis is thought to be a 
 factor, presents frequent recurrences, and is apt to lead to 
 serious results, since the blood is imperfectly absorbed; large 
 masses of connective tissue form, and these may cause sub- 
 sequent detachment of the retina. 
 
 Treatment consists of rest, attention to the predisposing 
 systemic affection, reduction of blood-pressure if elevated, and 
 calcium chloride to prevent recurrences. Later, in order to 
 favor absorption, iodides and iodine preparations, mercury, 
 diaphoresis, cathartics, and subconjunctival injections of nor- 
 mal saline solution. 
 
 Abscess of the Vitreous is a term used to designate 
 those cases of suppiu-ative iridochoroiditis in which the puru- 
 lerU exudate remains confined to the vitreous and choroid, and 
 does not spread to all the structures of the eye causing 
 panophthalmitis. This condition is described on p. 186. 
 
 Foreign Bodies in the Vitreous. — The entrance and 
 lodgment of a foreign body (metal, glass, wood) within the 
 globe usually causes severe inflammation and destruction of the 
 eyeball as a result of iridocyclitis or panophthalmitis unless 
 the substance be promptly extracted; the gravity of the acci- 
 dent depends upon the nature of the foreign body and the 
 
224 DISEASES OF THE VITREOUS 
 
 presence or absence of infection. Occasionally these sub- 
 stances, when small and free from infection, remain quiescent 
 and become encysted; but even in such cases there is danger 
 of subsequent inflammation. 
 
 The presence of a particle of iron for any length of time is 
 apt to cause a rusty-brown or greenish discoloration of the iris 
 and lens, known as siderosis. 
 
 Diagnosis. — The foreign body may have dropped to the 
 bottom of the vitreous cavity, become embedded in the walls, 
 or passed through the eyeball and be located in the orbit. If 
 the patient comes under observation soon after the injury, 
 before the media have become hazy, we may be able to see the 
 particle with the ophthalmoscope; and a careful examination 
 of the field of vision, disclosing a scotoma, may also locate it; 
 this information will be corroborated by a study of the site of 
 the wound of entrance and the probable direction which the 
 foreign body took. In most instances, a radiograph will re- 
 veal its presence and position. If it be of iron or steel, the 
 giant magnet (Fig. 210) will frequently indicate its presence 
 by the production of pain when the point is brought near the 
 eyeball, or by the bulging of the iris or the forward move- 
 ment of the lens when the particle is within these structures. 
 The use of the sideroscope, a magnetic needle suspended upon 
 a silk thread, will also aid in the diagnosis and localization, 
 the deflection of the needle increasing as it approaches the 
 foreign body. 
 
 Treatment. — If the substance is a piece of iron or steel, an 
 attempt to extract it with a magnet should be made at once. 
 We should also try to remove other foreign bodies (glass, 
 wood, copper, lead) as soon as possible after they have been 
 located, by means of delicate forceps; these are introduced 
 through the original wound or through an opening into the 
 vitreous cavity made at the point at which the foreign body 
 has been located. But if this is not accomplished promptly, 
 and very often it is- unsuccessful, we should allow the foreign 
 body to remain rather than stir up the vitreous, especially if 
 there be no symptoms of infection or irritation, and the 
 patient can be kept under constant observation; in such 
 
FOREIGN BODIES IN THE VITREOUS 
 
 225 
 
 cases, however, the question of enucleation may come up for 
 consideration at any time (p. 88). 
 
 Magnet Extraction. — Instruments used for the extraction 
 of particles of iron or steel are of two kinds: (1) Medium- 
 sized, or portable electro-magnets (Hirshberg's, Johnson's, 
 Sweet's), and (2) large, or stationary electro-magnets (Haab's, 
 Volkman's). In using the former (Fig. 211), the point of the 
 
 1 
 
 
 
 
 ■"■''i^Hi "7 
 
 
 Fig. 210. — Haab's Giant Electro-Magnet. 
 
 Fig. 211. — Medium-Sized, 
 Portable Electro-Magnet. 
 
 magnet is held at the entrance wound, or the opening made 
 at the location of the foreign body, preferably without pene- 
 trating into the vitreous cavity, and then the current is 
 turned on. If the giant magnet be employed, the patient 
 approaches the magnet, the eye is brought toward the point 
 of the instrument (Fig. 210), and the current gradually 
 turned on; the particle of iron or steel may be drawn out 
 through the original wound, or an attempt made to draw it 
 from the vitreous, around the lens, into the anterior chamber, 
 from which it is then removed through a corneal incision. 
 
 Even after successful extraction, the prognosis is always 
 serious; about one-third of the patients recover useful vision; 
 in quite a number the form of the eyeball is preserved; in 
 
226 DISEASES OF THE VITREOUS 
 
 many cases destructive inflammation supervenes. If the at- 
 tempt at extraction fails, enucleation is usually necessary. 
 
 If the eye presents evidence of infection when first seen or 
 after the foreign body has been extracted, we caimot hope to 
 save the organ. Attempts have been made to check the proc- 
 ess by the introduction of rods of iodoform into the aqueous 
 and vitreous cavities, or through galvanocauterization of lips 
 of the wound and adjacent parts, or by repeated irrigation of 
 the aqueous and even the vitreous cavities; but, as a rule, 
 such procedures are futile and the eye must be removed. 
 
CHAPTER XVII 
 
 DISEASES OF THE LENS 
 
 Anatomy and Physiology. — The crystalline lei%s is a transparent, col- 
 orless body, biconvex in shape, measuring 5 mm. in thickness and 9 mm. 
 in diameter in the adult, suspended in the anterior portion of the eyeball 
 between the aqueous and the vitreous chambers. It presents an an- 
 terior and a posterior surface, the latter being the more curved, an 
 anterior pole, a posterior pole, and a rounded circumference, the equa- 
 tor. It is devoid of blood-vessels except in foetal life, its nourishment 
 being derived from the ciUary body. It is enclosed in a transparent 
 capsule, and held in position by its suspensory ligament. The adult lens 
 consists of a peripheral portion, the cortex, and a central part, the 
 nucleus. The cortex is semi-soUd, softer than the nucleus, and color- 
 less; the nucleus is harder and has a yellowish tint; there is, however, 
 no sharp hmitation, the transition being gradual. The nucleus in- 
 creases in size with advancing years, and the cortex diminishes in pro- 
 portion; in old age the entire lens is of the consistence of the nucleus 
 and is hard and unyielding; this change is known as sclerosis. 
 
 In structure the lens consists of concentric laminae formed of long, 
 hexagonal fibres, the edges of which are connected by a cement sub- 
 stance, leaving fine lymph channels. The fibres either start or end 
 along Y-shaped or stellate figures, the lines of which radiate from the 
 anterior and posterior pole to the equator, each fibre encircling the 
 latter; the septa corresponding to the branches of the stellate figure 
 divide the lens into sectors. These stellate and Y-shaped figures can 
 often be recognized in the adult lens by oblique iUumination. 
 
 The capsule of the lens is a thin, .homogeneous, elastic membrane which 
 covers the lens, being known as the anterior capsule in front, and as the 
 posterior capsule behind. The anterior capsule is the thicker, and its 
 posterior surface is fined by a layer of cuboidal epithelium from which 
 the lens fibres are formed. 
 
 The suspensory ligament of the lens is a delicate membrane, extending 
 from the ciliary body to the lens capsule. It covers the inner surface 
 of the ciliary body from the ora serrata to the apices of the ciUary 
 processes, and then passes to the lens, dividing into three layers at- 
 tached respectively to the anterior capsule, the equator, and the pos- 
 terior capsule. Between these layers and the equator of the lens is an 
 annular space, triangular on section, known as the canal of Petit; it 
 communicates with the posterior chamber by means of sht-fike aper- 
 txires between the fibres of the anterior portion of the suspensory 
 ligament. 
 
 227 
 
228 DISEASES OF THE LENS 
 
 The function of the lens is to focus rays so that they form a perfect 
 image on the retina. To accomplish this, the refractive power of the 
 lens must change with the distance of the object, according to whether 
 the rays are parallel or divergent. This alteration in the refractive 
 power of the lens is known as accommodation, and is produced by a 
 change of shape mainly affecting its anterior curvature. 
 
 The lens presents variations in physical characteristics at different 
 periods of life. In the foetus, it is nearly spherical, slightly reddish, and 
 softer than at a later period. In the adull, its anterior surface is less 
 convex than the posterior, and its substance is firmer. Sclerosis, which 
 consists of a process of toughening, due chiefly to loss of water, begins 
 in the centre of the lens in childhood and advances slowly until adult 
 Ufe, after which its progress is more rapid, increasing the size of the 
 nucleus at the expense of the cortex. In old age, the lens increases 
 in size, is flattened, and assumes a yellow tinge, becoming tougher and 
 less transparent; this process of sclerosis accounts for the gray reflex 
 seen in the pupil of the aged, which may be mistaken for cataract 
 (senile reflex); it also explains the inabiUty on the part of the lens of 
 advanced years to change its shape for the purposes of accommodation 
 (presbyopia). 
 
 CATABACT 
 
 A cataract is any opacity of the lens or of its capsule or of 
 both. 
 
 Varieties. — Cataracts may be divided into: (1) Primary, 
 and (2) secondary to some other disease of the eye. 
 
 Cataracts are divided anatomically into: (l) Lenticular, situ- 
 ated in the substance of the lens; (2) capsular, affecting the 
 capsule; (3) capsulo-lenticular, involving both lens and capsule. 
 
 According to consistence, they may be (1) hard, (2) soft, and 
 (3) fluid. 
 
 They are also known as (1) partial, limited to some part of 
 the lens; (2) complete, involving the whole lens; (3) stationary, 
 when they remain incomplete; and (4) progressive, when they 
 spread and tend to affect the whole lens. 
 
 (Stationary cataracts include: (1) Anterior polar, (2) poste- 
 rior polar, (3) lamellar, and (4) various uncommon forms. 
 
 Progressive cataracts may be : (1) Senile, a. cortical, b. 
 nuclear; (2) congenital and juvenile, and (3) traumatic. 
 
 A convenient clinical classification of cataracts is the 
 following: 
 
CATARACT 229 
 
 1. Senile. 
 
 2. Congenital. 
 
 3. Juvenile. 
 
 4. Anterior Polar. 
 
 5. Posterior Polar. 
 
 6. Lamellar. 
 
 7. Various uncommon forms: a. central. 
 
 b. fusiform. 
 
 c. punctate. 
 
 8. Complicated. 
 
 9. After-cataract. 
 
 In patients under thirty-five all cataracts are of soft con- 
 sistence throughout and white in color; such cataracts have 
 no hard nucleus and are known as soft cataracts. After this 
 period the nucleus becomes hard and of a yellowish tint, and 
 the lenticular opacity is known as hard cataract. 
 
 Etiology. — ^According to etiology, cataract may be : 
 
 1. Congenital, due to faulty development or intra-uterine 
 inflammation of the eye. To this class belong anterior and 
 posterior polar, lamellar, and congenital complete cataracts. 
 
 2. Senile; this is the most common form. It usually 
 appears after the age of fifty. Cataract is not considered a 
 physiological but a pathological process; age is but a pre- 
 disposing factor. 
 
 3. Heredity has some influence in the occurrence of cataract. 
 
 4. General Diseases; diabetes is the most common example; 
 much less frequently, nephritis. 
 
 5. Occupation; cataract occurs frequently in glass-blowers 
 and others exposed to great heat. 
 
 6. Traumatic, by the production of an opening in the cap- 
 sule, thus allowing the lens to absorb aqueous; occasionally 
 by mere concussion, lightning stroke, or severe electric shock. 
 
 7. Ocular Diseases, causing complicated or secondary cata- 
 ract; the most common examples are infected corneal ulcers, 
 iridocyclitis, choroiditis, myopia of high degree, glaucoma, 
 and detachment of the retina. 
 
 8. Errors of Refraction seem to predispose, since most cata- 
 ract patients have hyperopia and hyperopic astigmatism. 
 
230 DISEASES OF THE LENS 
 
 S3nnptoms. — There is (1) diminished acuteness of vision, 
 depending upon the situation and extent of the cataract. It 
 is greatest when the opacity is central and diffuse, and least 
 when the cataract is peripheral. When central, the patient 
 sees best in dim light — ^with dilatation of the pupil. The 
 interference with vision increases with the progress of the 
 cataract, until finally there is mere perception of light. (2) 
 In the incipient stage, the patient may complain of seeing 
 spots which occupy a fixed position in the field. (3) Occa- 
 sionally there is annoying diplopia or polyopia, due to irregu- 
 lar refraction of the lens. (4) Myopia often develops during 
 the early stages,, due to increased refractive power of the lens; 
 for this reason the patient may be able to discard his reading- 
 glasses for the time; this condition is popularly known as 
 "second sight"; at the same time his vision for distance may 
 be improved with concave lenses, and there may be added 
 astigmatism. 
 
 Physical Signs. — There are no inflammatory s5miptoms. 
 During the incipient stage, examination by oblique illumina- 
 tion will show a grayish or whitish opacity on a black ground, 
 and with the ophthalmoscope at a distance a hlack opacity 
 upon a red field (Plate II). The pupil should be dilated, espe- 
 cially in the incipient stage. Later the entire pupil will 
 appear grayish and there will be an absence of fundus reflex. 
 During the stage of swelling the anterior chamber is reduced 
 
 in depth. 
 
 SENILE CATARACT 
 
 Senile or Simple Cataract is the most frequent form of cata- 
 ract. It is quite common after the fiftieth year; occasionally 
 it is seen as early as forty. Almost always both eyes are in- 
 volved, but generally one in advance of the other. The opac- 
 ity may begin either in the cortex (cortical. Figs. 212, and 
 28-29, Plate II), or in the nucleus (nuclear. Figs. 213, and 
 30-31, Plate II). As a rule, senile cataracts begin in the 
 cortex and the nucleus remains transparent throughout. The 
 time required for full development varies greatly; it may ripen 
 completely in a few months or may require many years; it 
 may become stationary at any stage of its progress. 
 
SENILE CATARACT 231 
 
 The Stages of senile cataract are four in number: 
 
 1. Incipient Stage. — The opacity most frequently begins 
 as streaks which extend from the periphery of the cortex, where 
 they are wider, to the centre of the 
 lens, where they narrow like the 
 spokes of a wheel (Fig. 212); the 
 periphery is affected first. These 
 streaks appear grayish by oblique a b c 
 illmnination, and black when seen ZrA:t:^\^^^ 
 
 with the ophthalmoscope. Between lumination; B, section of the 
 
 these sectors the lens is transparent. ^°'' ^' ^'™ '^^ '^' "p'^"""'- 
 
 ^ moscope. 
 
 Less frequently, senile cataract be- 
 gins with dot-like or cloud-like opacities situated in any por- 
 tion of the lens; sometimes the portion immediately surround- 
 ing the cortex becomes opaque (and, exceptionally, the nu- 
 cleus itself), constituting so-called nwcfear cataract (Fig. 213); 
 
 the last form causes relatively great 
 visual disturbance. Cataracts some- 
 times remain stationary in the incip- 
 A B "^ ient stage, with little impairment of 
 
 Fig. 213.— Senile Nuclear Cata- yisioU. HcnCe it is oftCU wise not 
 ract. A, Seen with Oblique H- , , , , j • j. i ■ j_ 
 
 lumination; B, Section of the to alarm the patient by acquaint- 
 Lens;c, Seen with the ophthai- ing him with Ws Condition, at the 
 
 moscope. .. • .■ .1 
 
 same time communicating the 
 knowledge to a relative, for om: own protection. 
 
 2. The Stage of Swelling {Immature Stage). — The lens ab- 
 sorbs fluid, swells, pushes the iris forward, and reduces the 
 depth of the anterior chamber. It appears bluish-white, shin- 
 ing, and presents distinctly the markings of the stellate figure. 
 During this stage, the iris casts a shadow upon the lens when 
 the eye is illuminated from the side, since the superficial por- 
 tion of the lens is still transparent, and hence the opaque 
 layer is some distance behind the iris. 
 
 3. Mature Stage. — The lens loses most of its fluid, shrinks 
 somewhat, and becomes perfectly opaque and of a dull gray or 
 amber color, the stellate markings still being recognizable. 
 The anterior chamber regains its normal depth, and there is no 
 shadow thrown by the iris on the lens with focal illumination. 
 
232 DISEASES OF THE LENS 
 
 Occasionally, the entire lens is changed into a hard, dark- 
 brown mass (black cataract). In this stage, the cataract 
 can easily be separated from the capsule of the lens; it 
 is then said to be " ripe " for operation, since it can be 
 extracted without leaving much if any of the cortex behind, 
 thus diminishing the chances of subsequent opacity (after- 
 cataract). 
 
 4. Hypermature Stage. — The cataract may continue in the 
 mature stage for a long time. If changes continue, the sur- 
 face of the lens loses its radial markings and becomes homo- 
 geneous, or presents irregular spots. The cataract may con- 
 tinue to lose water, and thus a shrunken, dry, flattened mass 
 results (shrunken cataract), with some deepening of the ante- 
 rior chamber. Or, the cortex may become soft, liquid, and 
 milky, and the nucleus sink to the bottom ©f this fluid (Mor- 
 gagnian cataract), the cataract appearing white with a brown- 
 ish coloring below. Very old hypermature cataracts often 
 present the deposit of cholesterin or of lime salts; the latter 
 change (chalky cataract) is found chiefly in complicated cata- 
 racts. The anterior capsule may become thickened and 
 opaque (capsulo-lenticular cataract). The lens (and iris) may 
 become tremulous through stretching of the suspensory liga- 
 ment. For these reasons, operation upon overripe cataract 
 is less favorable and more difficult than when mature. 
 
 Pathology. — The following changes -take place in the pro- 
 cess of formation of senile cataract: At first there is separa- 
 tion of the lens fibres with the formation of drops of fluid in 
 the spaces thus created; then the fibres swell, become cloudy, 
 present an uneven calibre, and disintegrate. Finally the lens 
 tissue is changed into a soft mass consisting of fat, drops of 
 fluid, remains of lens fibres, and albuminous liquid; this mass 
 becomes separated from the capsule by watery liquid. The 
 nucleus usually suffers no change except sclerosis. 
 
 Treatment. — Extraction of the lens by operation is the only 
 means for relieving a patient of senile cataract. No medicinal 
 treatment, whether local or constitutional, is of curative 
 value. There have been instances of the spontaneous clear- 
 ing of cataracts during the incipient and even in the mature 
 
SENILE CATARACT 233 
 
 stage; but such occurrences are so rare that they are consid- 
 ered curiosities. 
 
 In the incipient and maturing stages the eyes should be 
 rested as much as possible, correcting lenses be worn if an error 
 of refraction exists, deranged conditions of the system looked 
 after, and neighboring ocular disease be treated. The patient 
 should present himself for examination from time to time. 
 In cases in which the opacity is central, sight may be im- 
 proved temporarily by a weak solution of atropine (J gr. to 
 1 i.) or other mydriatic, the dilatation of the pupil permitting 
 increased vision through the peripheral, transparent portion 
 of the lens. The wearing of smoked glasses also accomphshes 
 this to a lesser extent and is generally a source of comfort. 
 
 The most favorable time for extraction of senile cataract is 
 when the lens is completely opaque and there is no shadow 
 thrown by the iris — i.e., when the cataract is ripe. If operated 
 upon before this time, the lens is not always removed cleanly 
 and some transparent cortex is apt to adhere to the capsule 
 and be left behind; this becomes opaque subsequently, and is 
 absorbed slowly, or an after-cataract develops necessitating 
 another operation — discission; besides, the remains of cortex 
 after extraction tend to produce irritation and interfere with 
 smooth healing. However, with the modern practice of re- 
 moving cortical remnants by irrigation of the anterior cham- 
 ber, the disadvantages of operating upon immature cataracts 
 have been lessened. 
 
 As a general rule, we operate when the cataract of one eye 
 is mature, and the other has progressed far enough to cause 
 considerable interference with vision. But there are a number 
 of exceptions to this rule : For instance, when the occupation 
 and circumstances of the patient are such that being unable to 
 work, he cannot wait for the cataract of the first eye to become 
 ripe; or when the cataract shows signs of hypermaturity 
 before the second eye is very much affected. Removal of 
 both cataracts should never be performed at one sitting. 
 When both eyes are affected, useful vision may be abolished 
 before either cataract is ripe. 
 
 Artificial Ripening is sometimes resorted to; this is accom- 
 
234 DISEASES OF THE LENS 
 
 plished by preliminary operations consisting of gentle massage 
 applied to the lens directly or through the cornea. An inci- 
 sion is made through the periphery of the cornea and the 
 aqueous humor allowed to escape, so that the cornea falls 
 against the lens; then the cornea over the pupil is stroked 
 with a smooth instrument, or the spatula or spoon may be 
 introduced into the aqueous chamber and applied directly to 
 the anterior capsule. Such direct or indirect massage may be 
 done with or without an accompanying iridectomy. Follow- 
 ing such operations, the lens becomes opaque after a few 
 weeks, and can then be extracted. Ripening operations are, 
 however, not always reliable nor entirely free from danger; it 
 is now generally considered safer and better to remove the 
 immature cataract than to resort to such artificial ripening. 
 Many operators regard the condition of immaturity in a cata- 
 ract as adding very little to the risks of extraction, especially 
 since the tenacious cortical remnants may be washed out by 
 irrigation of the anterior chamber with a warm, sterile saline 
 solution (0.6 per cent.). 
 
 Preliminary Capsulotomy, a method of artificial ripening 
 (Homer Smith), has given excellent results: In the morning 
 of the day selected for operation, the capsule of the lens is 
 divided as in cataract operation, the needle being passed 
 through the periphery of the cornea; this allows the aqueous 
 to penetrate; as a result the cataract swells and becomes 
 homogeneous, so that when, 6 hours later, the extraction is 
 performed, the lens escapes in one mass with little or no 
 cortex left behind. 
 
 Simple Extraction and Combined Extraction. — Extraction 
 may be performed with {Combined Extraction) or without 
 (Simple Extraction) an iridectomy; the question as to which 
 is preferable has been much discussed. Combined extraction 
 is the operation of choice in the majority of cases; it is 
 always indicated when the iris interferes with the easy deliv- 
 ery of the lens or protrudes during the operation and does not 
 stay reduced; when the lens is very large; when we suspect 
 that the patient may not behave well after the operation; 
 or when any ocular complications exist. ' Simple extraction 
 
SENILE CATARACT 235 
 
 is done in selected cases and has the advantage of leaving a 
 round pupil without a coloboma, and therefore slight improve- 
 ment in vision and appearance; its disadvantage is the danger 
 of prolapse of the iris, discovered at the first dressing and then 
 requiring immediate abscission. A preliminary iridectomy 
 and extraction several weeks later is often resorted to as a 
 means of lessening the risks of extraction when complications 
 are feared and in operating upon immature cataract. 
 
 Monocular cataract is not generally removed, since, owing 
 to the difference in refraction, the eyes will not work together. 
 Extraction may, however, be performed in such cases for cos- 
 metic effect, to prevent hypermaturity, and to extend the field 
 of vision on the affected side. 
 
 Aphakia. — ^After the extraction of cataract, the patient is 
 compelled to wear strong convex glasses, since as a result of 
 loss of the lens (aphakia), there is a high degree of hyperopia 
 and absence of the power of accommodation. This hyperopia 
 amounts to about lOD. With it there is usually considerable 
 astigmatism (1 to 3D), generally "against the rule." In an 
 average case, therefore, a convex spherical lens of about lOD, 
 combined with a convex cylinder of 1 to 3D, must be worn for 
 distant vision; to this sphero-cylinder an additional convex 
 sphere of 3 or 4D must be added for reading. Any previous 
 error of refraction will, of coiu'se, modify this correcting lens. 
 Glasses should not be prescribed until all signs of irritation 
 have disappeared — ^generally at the end of a month. Changes 
 in refraction may continue for several months. The aphakial 
 eye presents, besides hyperopia and loss of accommodation, a 
 deep anterior chamber and usually a tremulous iris; the images 
 normally seen on the anterior and posterior surfaces of the 
 lens are absent. 
 
 Prognosis. — A favorable result and useful vision follow cata- 
 ract extraction in the great majority of uncomplicated cases 
 (95 per cent.); there is very often excellent sight, and not 
 infrequently perfect vision. The prognosis is dependent not 
 only upon skilful operation, but upon careful selection, and 
 upon exclvMon of those complicated cases which cannot be 
 improved by an operation, no matter how successful, and also 
 
236 DISEASES OF THE LENS 
 
 those in which the conjunctival sac harbors germs capable 
 of infecting the wound. Hence the conjunctiva, lid margins, 
 and lacrymal sac must be carefully inspected, and if disease 
 is found, this must be cured before attempting an operation. 
 Cautious operators are in the habit of making a bacteriological 
 examination of the conjunctival discharge in every case. We 
 must be certain that there is no disease of the deeper struc- 
 tures of the eye and especially that the retina functionates 
 normally. We ascertain the condition of the optic nerve and 
 retina by testing with the candle for light perception and light 
 projection. There should be good perception of light, even 
 with feeble illmnination, and also a good field and projection. 
 Projection is tested by throwing light from the mirror of 
 the ophthalmoscope upon the upper, lower, inner, and outer 
 portions of the pupil; there is good projection, if, without 
 moving the eyes, the patient is able to state correctly the 
 direction from which the light comes. This test may also be 
 applied with the lighted candle made to approach the eye 
 from various directions, at a distance of one meter and also at 
 four meters. Although the cataract be fully matured, the 
 patient should be able to tell the position of the candle in vari- 
 ous parts of the field, with the eye fixed directly in front of 
 
 him. 
 
 CATARACT EXTRACTION 
 
 The operation of extraction is indicated for the removal of 
 all senile cataracts which are considered fit for operation; soft 
 cataracts after the age of fifteen (sometimes before this pe- 
 riod) ; soft cataracts which have been needled, or tramnatic 
 cataracts when glaucoma intervenes or to expedite cure; and 
 sometimes complicated cataracts. 
 
 The following description applies to the method of per- 
 forming simple extraction (without iridectomy), as most 
 commonly done. 
 
 Instruments Required: (1) An eye speculum (Fig. 214); 
 (2) a fixation forceps (Fig. 215); (3) a narrow Graefe knife 
 (Fig. 216); (4) a cystotome (Fig. 217); (5) a lens spoon (Fig. 
 218); (6) an iris repositor (Fig. 220); (7) a wire loop (Fig. 
 219). Since it may be necessary to do an iridectomy, we 
 
CATARACT EXTRACTION 
 
 237 
 
 must have ready, (8) curved iris forceps (Fig. 195); and (9) 
 curved iris scissors (Fig. 196). 
 
 Operation. — 1. The Corneal Section. After thorough 
 cleansing of the surrounding area including the lashes (some 
 operators cut the cilia close), the conjunctival sac is flushed 
 
 Fig. 216.— Graefe Knife. 
 
 Fig. 217.— Cystotome. 
 
 Fig. 218. — Lens Spoon. 
 
 Fig. 219. — ^Wlre Loop. 
 
 Fig. 214. — Eye 
 Speculum. 
 
 Fig. 215. — Fixation 
 Forceps. 
 
 Fig. 220. — Iris Repositor. 
 Figs. 214-220. — ^Instruments Required for Cataract Extraction. 
 
 with a large quantity of warm saline or boric solution. Local 
 anaesthesia by cocaine or holocain is ordinarily used, rarely a 
 general anaesthetic; subconjunctival injection of a few drops 
 of 4-per-cent. cocaine, below and at a little distance from the 
 limbus, will render the operation absolutely painless. The 
 operator stands behind the patient and inserts the eye specu- 
 lum; he seizes the eyeball near the lower margin of the cornea 
 with fixation forceps held in one hand, and, the patient looking 
 down, makes the corneal section with the other. This section 
 comprises about two-fifths of the circumference of the cornea 
 and is in the plane of its transparent margin. The Graefe 
 knife is thrust into the corneal margin above the horizontal 
 
238 
 
 DISEASES OF THE LENS 
 
 meridian, traverses the anterior chamber, and emerges at a 
 point opposite the puncture (Figs. 221 and 223). Pushing 
 the knife forward and cutting upward by a to-and-fro move- 
 ment, the section is completed in the same plane, close to the 
 
 Fig. 221.- 
 
 -Corneal Section in Cataract Fig. 222.- 
 Extraction. 
 
 -Delivery of the Lena in Cat- 
 aract Extraction. 
 
 iris, terminating at the upper margin of the cornea, where a 
 small conjunctival flap is usually made (Fig. 224). If the 
 operator is not ambidextrous he must stand at the patient's 
 side and in front when operating on the left eye, so as to 
 hold the knife in the right hand. 
 
 2. Opening the Capsule (Capsulotomy) . — The cystotome is 
 introduced flatwise into the anterior chamber, its point is 
 turned toward the capsule, and this is cut gently and without 
 pressure. There are many different methods of opening the 
 capsule : the incision may be T-shaped, or A-shaped, or + 
 -shaped, or peripheral and concentric with the corneal margin. 
 
 3. Delivery of the Cataract. — The speculum and fixation 
 forceps are removed, and the lens is expelled by pressing 
 gently upon the lower part of the cornea toward the centre of 
 the globe, with the back of a Daviel spoon. This causes gap- 
 ing of the section, in which the lens presents (Figs. 222 and 
 225) . After a greater part of the lens has passed through the 
 corneal wound, the spoon is made to follow up the lowest part 
 of the cataract, which is thus delivered and received upon the 
 
CATARACT EXTRACTION 239 
 
 wire loop. If the pupil is unyielding, and the iris impedes 
 the exit of the lens, it may be pressed backward with the wire 
 loop or a special iris retractor. 
 
 4. Cleansing {" Toilet ") of the Wound. — A few drops 
 
 Fig. 223. — Cataract Ex- Pig. 224. — Cataract Ex- FiG. 225. — Cataract Ex- 
 
 traction; Corneal Sec- traction; Conjunctival traction; Delivery of 
 
 tion. Flap. the Lens. 
 
 of antiseptic solution are instilled, the lids closed for a few 
 moments, after which the eye is inspected. If there are any 
 cortical remnants, these should be removed by rubbing the 
 edge of the lower lid upward over the cornea and by stroking 
 with the spatula; blood clots may be expelled in the same 
 manner; the lips of the wound must also be freed from lens 
 particles with a spatula. Care should be taken that the 
 lashes do not touch the wound. Frequently the anterior 
 chamber is irrigated with a rubber bulb provided with a 
 delicate glass tip or a special irrigating apparatus, using warm 
 sterilized saline solution (0.6 per cent.); but this may be 
 unnecessary if no remnants of cortex seem to have been left. 
 If the iris fails to regain its natural position, we exert gentle 
 pressure upon the lower margin of the cornea, so as to cause 
 the wound to gape and thus disentangle the iris; if this does 
 not succeed we introduce the iris repositor into the anterior 
 chamber, and smooth out the iris until the pupil becomes 
 round and central. If we fail in this, and the iris shows a 
 tendency to become displaced again or to prolapse, a small 
 portion is excised. The conjunctival flap is next adjusted, 
 the eye washed out with a few drops or flushed with a greater 
 quantity of antiseptic solution, and the lids are closed. 
 
 5. Dressing. — The dressing varies. Most operators cover 
 the lids of both eyes with an oval piece of gauze soaked in an 
 antiseptic solution, upon which a quantity of dry absorbent 
 
240 
 
 DISEASES OF THE LENS 
 
 Fig. 226.— Ring's Ocular Mask. 
 
 cotton is placed, and then confine these with strips of adhe- 
 sive plaster passing from below the orbit to above the brow; 
 
 the dressing is often confined by 
 a binocular bandage. A few op- 
 erators close the lids with isin- 
 glass plaster without any other 
 dressing. Often protective covers 
 (aluminum, wire, stiff cloth, Fig. 
 226) are used to prevent injury to 
 the operated eye. 
 
 After-treatment. — The patient 
 must lie quietly upon his back; 
 an anodyne is often advisable; 
 after twenty-four hours he may 
 change to the unoperated side. 
 His food should be fluid for the 
 first few days. The bowels need not be emptied for four 
 days; if a movement occurs . before this, there must be no 
 straining. The wound is inspected after twenty-four 
 hours; if prolapse of iris has occurred, it is excised. Atropine 
 is instilled as soon as the wound is closed. On the fifth day 
 the unoperated eye may be left free, and the patient may sit 
 up in bed for an hour or two; after a week a light dressing 
 (Fig. 375) is applied and the patient may sit in an easy-chair; 
 after 10 days smoked glasses need be the only protection. 
 
 Modifications in the Operation. — Many (probably most) 
 operators make a small iridectomy in every cataract extrac- 
 tion (Combined Extraction, p. 234). There are many varia- 
 tions in the situation of the section. 
 
 Linear Extraction. — In this modification, suitable for soft 
 and traumatic cataracts and cataract masses produced by 
 needling, a small corneal section (about 5 mm.) is made 1 mm. 
 within the margin of the cornea with the keratome, the pupil 
 having been dilated; the capsule is freely torn with the cysto- 
 tome or opened with the keratome directly after it penetrates 
 the cornea; then the lens masses are evacuated by depressing 
 the posterior lip of the wound with the wire loop and pressing 
 upon the cornea. A small iridectomy is sometimes made. 
 
CATARACT EXTRACTION 241 
 
 Extraction of Cataract in its Capsule has been revived and 
 advocated by East Indian oculists, notably Major Smith, 
 who have the opportunity of operating upon enormous num- 
 bers. The steps of this operation are similar to those used 
 in ordinary extraction except that capsulotomy is omitted, the 
 lens being expressed within its capsule by pressure upon the 
 cornea with a squint hook which dislocates the lens and rup- 
 tures its suspensory ligament. Though after-cataract is 
 avoided and post-operative inflammations are lessened by this 
 modification, there is prolapse of vitreous in many cases. On 
 this account, this operation is not often selected excepting in 
 India, though it may have its advantages in extraction of 
 immature cataract. 
 
 The Complications of Cataract Extraction include loss of vit- 
 reous, dislocation of the lens, insufficient opening in the cornea 
 or capsule, wounding the iris, prolapse of the iris, incomplete 
 evacuation of the cataract, and intraocular hemorrhage. 
 
 The Complications in the Healing-Process include prolapse 
 of the iris, striated keratitis, glaucoma, iritis, iridocyclitis, 
 cyclitis, suppuration of the wound, panophthalmitis, and in- 
 traocular hemorrhage. 
 
 Congenital Complete and Juvenile Complete 
 Cataracts are rather infrequent. The lens is uniformly 
 white, bluish-white or pearly, and always soft, sometimes 
 fluid and milky. These cataracts may occur in otherwise 
 perfectly healthy eyes, or they may be complicated cataracts, 
 with changes in the retina, choroid, or optic nerve. . One or 
 both eyes are affected. The congenital complete cataract is 
 due to a disturbance of development or intrauterine ocular 
 inflammation. The complete cataract of young people {juve- 
 nile) may be hereditary, or arise without known cause; in 
 some cases there is a history of convulsions. 
 
 Treatment consists in discission (needling) soon after the sec- 
 ond year, so that disuse of sight may not cause amblyopia. The 
 needle operation must usually be repeated a number of times; 
 sometimes there are remains of the lens which do not become 
 absorbed and must subsequently be removed by linear extrac- 
 tion. Semifluid cataracts are removed by linear extraction. 
 
242 
 
 DISEASES OF THE LENS 
 
 Anterior Polar Cataract {Pyramidal Cataract). — This 
 partial and stationary lenticular opacity occurs in the form of 
 a small, round, white opacity; often pyramidal in shape, situ- 
 ated at the anterior pole of the lens, beneath the capsule (Fig. 
 227). It may be congenital or acquired. The acquired form 
 
 ABC 
 
 Fig. 227. — ^Anterior Polar Cataract. A, 
 Seen with Oblique Illumination; B, 
 Section of Lens; C» Seen with the 
 Ophthalmoscope. 
 
 ABC 
 Fig. 228. — Acquired Form of Posterior 
 Polar Cataract. A, Seen with Oblique 
 Illumination; B, Section of the Lens; 
 C, Seen with -the Ophthalmoscope. 
 
 originates from an ulcer of the cornea in early childhood;-such - 
 an ulcer perforates and allows contact and pressure between 
 lens and cornea, setting up an irritation in the anterior cap- 
 sule which results in a proliferation of the subcapsular epi- 
 theUum; afterward the anterior chamber is restored; some- 
 times there is an accompanying corneal opacity. As a rule 
 this form of cataract causes little if any reduction in vision. 
 
 Posterior Polar Cataract. — This form may be congen- 
 ital (capsular) or acquired (cortical). 
 
 The congenital form is a capsular opacity consisting of a 
 small, round, white deposit, situated at the posterior pole; 
 with the ophthalmoscope it appears as a black dot upon the 
 red fundus-reflex. It represents the remains of the hyaloid 
 artery at the point of attachment to the posterior capsule of 
 the lens. It causes but trifling interference with vision and 
 requires no treatment. 
 
 The acquired form is a grayish, stellate opacity of larger 
 size, situated in the cortical layer of the lens, at its posterior 
 pole (Fig. 228). It is a form of secondary cataract which 
 develops in connection with high myopia, choroiditis, and 
 retinitis pigmentosa. It remains stationary for many years, 
 but is apt finally to become complete. In this affection there 
 is considerable impairment of vision, caused not only by the 
 cataract, but also by the accompanying disease of the deep 
 structures. Sometimes a similar condition is found near the 
 
PARTIAL CATARACTS 243 
 
 anterior pole of the lens. Such secondary cataracts do not 
 admit of operation on account of the accompanying ocular 
 disease. Occasionally a posterior polar (cortical) opacity 
 exists without evident affection in other parts of the eye. 
 
 Liamellai* or Zonular Cataract. — This variety of 
 •partial, stationary cataract is either congenital or forms in 
 infancy, and usually affects both eyes. It is the most common 
 form of cataract seen in children. It is sometimes heredi- 
 tary, and often associated with a 
 history of convulsions and with 
 the changes of rickets, especially 
 in the teeth, cranial and other 
 bones. It consists of a gray, disc- ^ ^ 
 
 ... .^ J ii 7 ° •' ' Fig. 229.— Zonular Cataract. A, 
 
 like opacity of the layer surround- seen with obuque illumination; 
 
 ing the transparent nUcleU^S, with ^- section of the Lens; C, seen 
 , ,, , . 1 /T-1. with the Ophthalmoscope. 
 
 clear cortex on the outside (Fig. 
 
 229). When the pupil is dilated, examination by oblique 
 illumination shows a grayish disc surrounded by clear lens 
 substance; from the margin of the opacity short strise are 
 often seen projecting into the surrounding transparent cor- 
 tex. The cataract is most dense at the margin of the disc; 
 this distinguishes it from nuclear cataract. With the oph- 
 thalmoscope at a distance, we see a dark disc surrounded 
 by a zone of red fundus-reflex; the disc is somewhat lighter 
 in the centre than at the periphery. 
 
 Lamellar cataract usually remains stationary, but occasion- 
 ally becomes complete. It causes interference with vision; 
 the amount may be slight or decided, depending upon the 
 density of the opacity. 
 
 Treatment. — ^When sight is considerably interfered with we 
 can improve vision by iridectomy, by discission in the young, 
 or by extraction in older persons. Iridectomy (small coloboma 
 downward and inward) is indicated when the vision is very 
 materially improved after the use of a mydriatic; its advan- 
 tages are that the patient does not require strong convex 
 lenses and often retains binocular vision; its disadvantages 
 are the elongated pupil, and some dazzling due to this. Re- 
 moval of the lens by discission or extraction is radicated in 
 
244 DISEASES OF THE LENS 
 
 those cases in which there is Httle or no improvement in sight 
 after dilatation of the pupil, and when there are indications of 
 progress of the cataract. 
 
 Various Uncommon Varieties of Stationary, Pari:ial 
 Cataract are met with. These include (1) central cataract, a 
 small, white opacity in the centre of the lens, (2) fusiform 
 cataract, a spindle-shaped opacity running from the anterior 
 to the posterior pole, and (3) punctate cataract, consisting of 
 a number of very small, white dots variously distributed 
 through the lens. These opacities are usually congenital, 
 cause little interference with vision, but are often associated 
 with other ocular defects. 
 
 Complicated or Secondary Cataracts accompany or 
 follow other diseases of the eye. The most frequent ocular 
 affections which lead to cataract are iridocyclitis, choroiditis, 
 high myopia, severe forms of corneal ulcers, glaucoma, reti- 
 nitis pigmentosa, and detachment of the retina. Such cata- 
 racts frequently begin in the posterior part of the lens, often 
 have distinctive features, and tend to degenerate. It is im- 
 portant to establish the fact that a cataract is complicated 
 when the question of operation presents itself. The treatment 
 of complicated cataracts is usually very unsatisfactory and the 
 prognosis is always much, less favorable than in uncompli- 
 cated cases. This is because the operation is rendered diffi- 
 cult and the effect on sight disappointing by the complicating 
 ocular disease; many cases cannot be operated upon. 
 
 Traumatic Cataract is the result of a perforating wound 
 of the lens capsule, occasionally of contusions of the eyeball 
 without visible perforation (concussion cataract). Within a 
 few hours the injured portion of the lens becomes cloudy from 
 absorption of aqueous, and swells; opaque and swollen lens 
 substance protrudes through the capsule wound and often 
 falls into the anterior chamber; swelling and clouding con- 
 tinue until the entire lens has become opaque. Then the lens 
 substance becomes absorbed; in favorable cases in young per- 
 sons spontaneous cure with a clear, black pupil results. More 
 frequently, however, part of the lens remains opaque in the 
 capsule and requires subsequent operation. Occasionally the 
 
TRAUMATIC CATARACT 245 
 
 opacity of the lens remains limited to the injured portion, and 
 in rare cases such a stationary cataract becomes absorbed. 
 The course described may be less favorable: iritis, iridocy- 
 clitis, or secondary glaucoma from swelling of the lens may 
 occur. Contusions of the eye may be followed not only by 
 concussion cataract, but by a brownish ring-shaped opacity 
 (Vossius' ring) on the anterior capsule, corresponding to the 
 margin of the iris and supposed to represent adhesion of iris 
 pigment. 
 
 Treatment. — Immediately after the injury, absolute rest and 
 atropine are to be employed. If the rapid swelling of the 
 lens causes inflammation and much increase of tension, the 
 cataract should be removed by extraction. But if such com- 
 plications do not arise, it is wiser to allow absorption to pro- 
 ceed, and to defer operative intervention until there is no 
 irritation or inflammation, and spontaneous improvement has 
 come to a standstill. 
 
 After-Cataract (often called Secondary Cataract) is an 
 opacity of the lens capsule seen in many instances after 
 cataract operation; it consists of remnants of lens cortex, of 
 proliferation of remaining subcapsular epitheliiun, or of prod- 
 ucts of inflammation (new coimective tissue). The mem- 
 brane thus formed may be thin and delicate or thick and 
 tough, and the degree of subsequent diminution in the im- 
 provement in sight following the cataract operation will vary 
 accordingly. When due to inflammatory products, the mem- 
 brane is apt to be thick and the iris adherent. 
 
 Treatment consists in dividing the membrane {discission), 
 
 after all signs of irritation or inflammation have subsided, 
 
 usually two or three months subsequent to the cataract 
 
 extraction. 
 
 DISCISSION OR NEEDLING 
 
 This operation is indicated in zonular, congenital com- 
 plete, and juvenile complete cataracts (soft cataracts), pre- 
 vious to the fifteenth year, as a preliminary step in extraction 
 in cases of high degree of myopia and for the division of after- 
 cataract. The operation differs according to whether the lens 
 is present or whether we are dealing with an after-cataract. 
 
246 
 
 DISEASES OF THE LENS 
 
 Discission when the lens is present. — In very young children 
 a general ansesthetic is required; in others, local anaesthesia is 
 sufficient. The pupil must be dilated. The speculiun is in- 
 troduced and the eyeball steadied with the fixation forceps. 
 A knife-needle (Fig. 230) is thrust 
 through the outer margin of the cornea 
 and then through the capsule of the lens, 
 making two cross cuts, each about 4 mm. 
 in length (Fig. 231). These cuts must 
 be superficial, especially if this is the first 
 operation, so that there will not be too 
 rapid swelling of the lens. The lens 
 substance may be broken up a little 
 by rotating the needle. After some of 
 the swollen lens matter has been ab- 
 FiG. 230.— Knife-needles, sorbcd (scvcral weeks), the operation 
 must be repeated; at the second opera- 
 tion the discission may be deeper and bolder. At the last 
 of the several operations, the incision must include the 
 posterior capsule. 
 
 After-treatment. — 
 There is usually very 
 little reaction. The pu- 
 pil must be kept di- 
 lated with atropine. 
 The lens substance 
 swells, protrudes 
 through the opening in 
 the capsule, and pieces 
 fall into the anterior 
 
 chamber and become absorbed. Usually three operations are 
 required. The entire duration of treatment is severa' months. 
 Complications. — Rapid and extensive swelling of the lens 
 may cause secondary glaucoma requiring rernoval of the lens 
 by linear extraction, with or without iridectomy. A bold dis- 
 cission is sometimes done, with a view of extracting the lens a 
 few days afterward, as soon as there is marked swelling; this 
 is the usual procedure when the lens is removed in high de- 
 
 FlG. 231. — Discission of the Lens. 
 
DISCISSION 247 
 
 grees of myopia. Iritis may occur after discission, occasion- 
 ally iridocyclitis, and very rarely loss of the eye. 
 
 The Suction Method is occasionally used after discission of 
 soft cataracts, and in fluid or semifluid cataracts: A small 
 corneal wound is made and the capsule lacerated; by means 
 of a tube the lens matter is sucked out, either by mouth or 
 suction-syringe. This method is not in general use. 
 
 Discission for After-Cataradt. — If the opacity is thin and 
 delicate it is divided by means of a knife-needle (Fig. 230) 
 introduced through the conjunctiva 1 mm. external to thelim- 
 bus, the pupil having previously been dilated; a T-shaped or 
 -|— shaped incision is made, care being taken that the instru- 
 ment is sharp, and that there is no dragging on the iris or 
 ciliary body, for fear of subsequent inflammation. Such 
 membranes are occasionally cut by introducing the knife- 
 needle from behind, through the sclera. If the membrane is 
 thick and tough, it may be divided by two knife-needles, one 
 entering at each side of the periphery of the cornea, meeting 
 in the centre of the pupil and then separating. When the 
 iris is adherent it will be necessary to perform iridotomy or 
 a similar operation (p. 174). Discission of after-cataract is 
 sometimes followed by glaucoma, and occasionally by irido- 
 cyclitis and suppuration. 
 
 DISLOCATION OF THE LENS 
 
 Dislocation of the lens may be partial or complete. 
 
 Ssmiptoms are disturbance of vision, interference with ac- 
 commodation, a change in refraction, monocular diplopia, and 
 tremulous iris. They differ according to whether the dis- 
 placement is partial or complete. In addition there may be 
 complications and sequelae. 
 
 Partial Dislocation (Subluxation) may consist of a tilting of 
 one edge of the lens, or of a lateral displacement — ^upward, 
 downward, inward, or outward. In such cases the anterior 
 chamber will be of unequal depth, being increased where the 
 lens is absent. The convex edge of the lens can usually be seen 
 (Fig. 232) in some part of the pupil, the portion of the latter 
 which is free from lens being particularly black. With the 
 
Fig. 232. — Dislocation of the Lens 
 
 248 DISEASES OF THE LENS 
 
 indirect method of ophtlialmoscopy, the optic disc appears 
 double, one image being seen through the lens and the other 
 through the free pupil. Movements of the ej'eball disclose a 
 
 trennilous condition of the lens 
 and iris (iridodonesis). There 
 is considerable myopia in the 
 area corresponding to the lens, 
 the convexity of the latter 
 being increased through relax- 
 ation of the suspensory liga- 
 ment; also marked astigma- 
 tism. Monocidar diplopia is 
 Upward and Outward. Complained of, two imagcs be- 
 
 ing formed on the retina. The 
 subluxated lens may become opaque, and this adds to the 
 visual disturbance. 
 
 Complete Dislocation {Luxation) occurs when the lens is 
 displaced anteriorly into the aqueous, or posteriorly into the 
 vitreous cavity. In traumatic cases in which there is rupture 
 of the sclera, the lens may lie beneath the conjunctiva. 
 
 When dislocated anteriorly, the lens is easily recognized. 
 If transparent, it looks like a large drop of oil with a curved, 
 golden margin when seen by oblique illumination. The ante- 
 rior chamber is increased in depth. 
 
 When displaced into the vitreous, the lens sinks into the 
 lowest part, and either becomes attached to the fundus by 
 exudation or moves about; when opaque, it can be seen with 
 the ophthalmoscope and sometimes with the unaided ej'e. 
 The anterior chamber is deep, the iris tremulous, and the pupil 
 very black. The eye is, as in aphakia, in a condition of ex- 
 treme hyperopia and has lost its power of accommodation. 
 Complications and Sequelae. — A partial dislocation often 
 changes to a complete one. When subluxated, the lens may 
 remain clear a long time, but completely dislocated lenses 
 soon become opaque. Choroiditis and iridocyclitis, secondary 
 glaucoma, and even sympathetic ophthalmia sometimes fol- 
 low. Displacement into the vitreous is tolerated better than 
 anterior luxation. 
 
DISLOCATION OP THE LENS 249 
 
 Etiology. — Dislocation of the lens may be either congenital 
 or acquired. In order that the lens can become dislocated 
 there must be some defect in the suspensory ligament such as 
 rupture, stretching, or imperfect development. 
 
 The congenital form is partial, usually upward, often be- 
 comes complete in after-years, is generally bilateral and 
 symmetrical, and sometimes hereditary. 
 
 The acquired forms are either traumatic or spontaneous. 
 Traumatic dislocation is generally the result of contusions. 
 The predisposing cause of spontaneous dislocations is degen- 
 eration of the suspensory ligament seen in fluid vitreous, 
 choroiditis, and myopia of high degree, detachment of the 
 retina, and hypermature cataract; the exciting cause may be 
 insignificant, such as various straining efforts. 
 
 Treatment. — In partial dislocation, if no ssonptoms of irri- 
 tation are produced, treatment consists in prescribing suitable 
 glasses, usually strong convex lenses, to correct the refraction 
 of the aphakial portion. When the lens is dislocated into the 
 anterior chamber it should be removed through a corneal inci- 
 sion, after having pierced the lens with a needle to prevent 
 its dislocation into the vitreous. If dislocated into the vitre- 
 ous, extraction is indicated but' difficult; if symptoms of irri- 
 tation arise, the lens may be removed with the wire loop 
 through a corneal incision; strong convex glasses are pre- 
 scribed for the aphakia. If inflammatory symptoms occur 
 in a case in which the dislocated lens cannot be removed, an 
 iridectomy may be tried; if, in such cases, the eye is sightless, 
 enucleation is indicated. 
 
CHAPTER XVIII 
 
 DISEASES OF THE RETINA 
 
 Anatomy. — The retina is a thin, delicate membrane which consists, 
 among other parts, of an expansion of the optic nerve. It is placed be- 
 tween the hyaloid membrane of the vitreous internally, and the choroid 
 externally. It extends forward to the ciliary body where its termi- 
 nation is called the ora serrata; devoid of nerve fibres, simpler and 
 thinner, it is continued over the inner surface of the ciUary body and 
 the posterior surface of the iris. In the living eye, it is transparent 
 and of a purple red color; under the influence x)f light, it is quickly 
 bleached; after death, it soon becomes opaque and white. The re'tina 
 is connected with the subjacent choroid at the entrance of the optic 
 nerve and at the ora serrata; elsewhere it simply lies upon this tunic 
 but is not attached to it. When we detach the retina, the pigment 
 cells which form its outermost layer adhere to the choroid, and on this 
 account were formerly described as part of the latter. 
 
 The inner surface of the retina presents in the axis of the eyeball the 
 yellow spot or macula luiea, about 1 to 2 mm. in diameter, and in its 
 centre a small depression, the fovea centralis; this is the region of most 
 distinct vision, and the part of the retina which is made to receive the 
 image when we wish to get an exact impression of an object. About 
 3 mm. to the inner side of the posterior pole of the eye is a pale, round 
 area, the head of the optic nerve (papilla or disc), corresponding to the 
 point where the optic nerve pierces the retina (Fig. 43). The circum- 
 ference of the disc is sUghtly elevated above the surface of the retina, 
 but the centre presents a depression, the physiological cup or excavation; 
 here the blood-vessels of the retina enter the eye. The ophthalmo- 
 scopic appearances of the background of the eye and the distribution 
 of the retinal vessels are given in Chapter III. 
 
 The central artery of the retina, accompanied by the corresponding 
 vein, pierces the optic nerve about 2 cm. from the globe, and passes 
 between the bundles of fibres to the inner surface of the retina at or 
 near the middle of the disc. Excepting at the papilla, where minute 
 communications are sometimes found between retinal and ciliary ves- 
 sels, the retinal arteries have no anastomoses ; they are terminal branches ; 
 hence in obstruction of the central artery there is no compensatory col- 
 lateral circulation, and blindness results. The retinal vessels lie in the 
 inner layers; the external layers are destitute of blood-vessels and are 
 nourished by the adjacent choriocapillaris. The fovea has no blood- 
 vessels; in this situation, the choriocapillaris is thickened. The blood- 
 vessels are surrounded by sheaths forming the lymphalics of the retina. 
 
 250 
 
ANATOMY OF THE RETINA 
 
 251 
 
 CUjomU^^iw^i 
 
 The minute anatomy of the retina is very complicated. We distin- 
 guish two kinds of tissue: (1) nervous elements, of which there are eight 
 layers, and (2) supporting tissue (Mueller's fibres). The supporting 
 tissue comprises the internal and external limiting membranes and 
 numerous fibres serving to keep the deUcate 
 nerve tissue in proper position and to insulate 
 the nervous elements. 
 
 Microscopic examination shows the following 
 layers of the retina, from within outward (Fig. 
 233): 1. The internal limiting Tneinhrsi,ne. 2. The 
 layer of nerve fibres, consisting of the expan- 
 sion of the fibres of the optic nerve destitute of 
 meduUary layer after piercing the eyeball. 3. 
 The layer of ganglion cells, a stratum of large, 
 branching nerve cells. 4. The inner plexiform 
 layer. 5. The inner nuclear layer. 6. The 
 outer plexiform layer. 7. The outer nuclear layer. 
 8. The extemal'limiting membrane. 9. The layer 
 of rods and cones, the hght-perceiving layer. 
 10. The layer of pigment cells which bounds 
 the retina externally and consists of a single 
 stratum of hexagonal pigmented cells. 
 
 The rods are much more numerous than the 
 cones, excepting at the macula where the cones 
 preponderate. At the fovea there are no rods, 
 and the cones, longer and narrower than else- 
 where, are found exclusively. In this spot also, 
 all the layers of the retina are much thinner, 
 there is no nerve-fibre layer, and Mueller's fibres 
 are arranged obUquely. The disc consists of 
 optic-nerve fibres exclusively; it has no other 
 retinal nerve elements and has no power of 
 sight; hence it is called the blind spot. 
 
 Physiology. — The action of light chang es the vis- 
 ual purple contained in the outer se gments of 
 the rods into a colorles s subs tance. When the 
 eye is in the dark, most of tiie pigment is stored 
 in the posterior portion of the cells of the pig- 
 ment epithelium and is withdrawn from between the rods. After ex- 
 posure to Ught, the pigment granules push their way inward into the 
 processes extending between the rods and cones, and the latter become 
 contracted and shortened. The function of the pigment cells is the 
 renewal of the visual purple of the outer segments of the rods after 
 the bleaching produced by exposure to light. 
 
 The rods and cones, the terminal organs of the optic nerve, receive 
 waves of Ught which fall upon the retina and convert these vibrations 
 
 Fig. 233. — Vertical 
 Section of the Ret- 
 ina (Modified from 
 Sehultze). The 
 Numbers refer to 
 the Text. 
 
 V 1= 
 
252 DISEASES OF THE RETINA 
 
 into nervous impulses which are carried by the optic nerves (the fibres 
 of which represent the axis cyUnders of the ganglion cells) and the optic 
 tracts to the brain; here they produce the sensation of light. When the 
 image of an object falls upon the macula, there is distinct vision; when 
 it falls upon any other part of the retina, there is indistinct vision. Two 
 points give rise to separate visual impressions when their images are at 
 least 0.002 mm. apart, since this represents the diameter of the cones at 
 the fovea; images which are closer than this would only stimulate one 
 cone and consequently create but one visual impression. In other 
 words, to be seen distinctly, two objects must subtend a visual angle of 
 one minute or more. 
 
 Images of an object give rise to a single visual impression when they 
 fall upon corresponding retinal areas; otherwise there are double images. 
 In binocular vision certain portions of the retina are associated; thus the 
 upper halves of the retinae correspond, as do also the lower halves; but 
 the nasal side of one retina corresponds to the temporal half of the other, 
 and vice versa. 
 
 Rays of light impinging upon the retina come from the opposite side 
 of the field; thus the upper part of the retina is used for seeing objects 
 in the lower part of the field, the temporal portion of the retina for the 
 nasal part of the field, etc. The image on the retina is always inverted. 
 
 Affections of the Retina may be divided into: 
 
 a. Inflammation, the various forms of retinitis: (1) simple, 
 
 (2) deep, (3) albuminuric, (4) diabetic, (5) leukaemic, (6) 
 syphilitic, (7) hemorrhagic, (8) septic, (9) uncommon forms of 
 retinal changes. 
 
 b. Circulatory Disturbances: (1) hypersemia, (2) anaemia, 
 
 (3) hemorrhages, (4) arteriosclerosis, (5) embolism, (6) 
 thrombosis. 
 
 c. Pigmentary Degeneration. 
 
 d. Detachment. 
 
 e. Tumor: glioma (see chapter on Intraocular Tumors). 
 
 RETINITIS 
 
 Inflammation of the retina presents various clinical types. 
 There are, however, certain signs and symptoms which are 
 more or less common to all varieties. Retinitis may be pri- 
 mary, or secondary, when it is an extension of inflammation of 
 neighboring oculai structures. It usually extends to both the 
 papilla and the choroid. When the involvement of the en- 
 
RETINITIS 253 
 
 trance of the optic nerve is marked, we speak of the affection 
 as neuroretinitis ; when the choroid is prominently implicated, 
 we call the condition choroidoretinitis. The disease may be 
 confined to one eye; but since it is generally dependent upon 
 a constitutional factor, it is almost always bilateral. It may 
 ■ be acute in course, but as a rule it lasts many weeks or even 
 several months. 
 
 Objective Symptoms. — There are no external signs; the ob- 
 jective symptoms are all ophthalmoscopic : Diffuse clouding of 
 retinal details, especially in the region of the papilla; conges- 
 tion of the disc with indistinctness of its edges; circumscribed 
 exudations appearing as soft, white, or slightly yellow spots 
 or patches, discrete or confluent, varying in size, and found 
 principally along the retinal vessels and at the macula; tor- 
 tuosity and distention of the vessels, seen principally in the 
 veins which are darker than normal; the vessels may be 
 obscured in parts by swelling and exudation; hemorrhages of 
 various shapes and sizes, rounded when occurring in the 
 deeper layers, and feathery or flame-shaped when superficial; 
 opacities of the vitreous. 
 
 Subjective Symptoms. — Diminution in acuteness of vision 
 varying with the severity and extent of the retinitis and the 
 situation of the exudates, but generally considerable; changes 
 in the field of vision: there may be concentric or irregular con- 
 traction, or scotomata; alterations in the shape of objects: 
 micropsia, objects appearing smaller than they really are; 
 macropsia, objects appearing larger than normal; metamor- 
 phopsia, a distortion of the shape of objects, straight lines 
 appearing wavy and bulging; diminution of the light sense; 
 feeling of discomfort in the eyes; photophobia may be present, 
 but pain is rare. 
 
 Cotirse. — The inflammation may subside completely and 
 useful vision return; or certain changes may occur in the 
 retina as a result of atrophy, causing considerable impairment 
 or absolute loss of vision. These changes are: Atrophy of the 
 retina allowing the choroidal vessels to become visible; 
 bright, white patches and dots replacing hemorrhages or exu- 
 dation and frequently pigmented; contraction of the vessels, 
 
254 DISEASES OF THE RETINA 
 
 which are bordered by white lines; atrophy of the disc, which 
 presents an indistinct outline and a pale, dirty color (ret- 
 initic atrophy). The prognosis depends upon the severity 
 of the inflammation, the parts of the retina most involved 
 (unfavorable when the macula has suffered), and the clinical 
 form of the retinitis. 
 
 Pathology. — The changes consist of congestion, oedema, 
 exudation of leucocytes and fibrin, changes in the vessel walls, 
 fatty degeneration, pigmentation, and extravasation of blood. 
 The white spots are due to exudation of leucocytes and fibrin, 
 swelling of nerve fibres and cells, and fatty degeneration of 
 the retinal elements and of exudation. The walls of the 
 blood-vessels become thickened and the calibre is sometimes 
 obliterated. Later, the retina becomes atrophied and then 
 consists largely of connective tissue presenting considerable 
 pigment, the nerve elements disappear, and the blood-vessels 
 present thickened walls, sometimes replaced by solid cords. 
 
 Etiology. — Retinitis occurs occasionally as a local lesion. 
 But generally it is merely a manifestation of a constitutional 
 disease, such as nephritis, diabetes, syphilis, etc., a list of 
 which is given on p. 252; or it may be due to abnormal con- 
 ditions of the blood and blood-vessels, metastasis, and auto- 
 intoxication; or it may be an extension from an iritis, cyclitis, 
 or choroiditis. 
 
 Treatment. — The local treatment consists in absolute rest 
 for the eyes, protection from light, either by smoked glasses or 
 the darkened room, and often the use of atropine. Internally, 
 we give small doses of mercury, also iodide of potassium. 
 Diaphoretics are useful, and sometimes cathartics. In addi- 
 tion, it is of the greatest importance to treat the constitu- 
 tional condition which is the cause of the retinal lesion. 
 
 Types. — Retinitis was formerly described under the terms 
 serous and parenchymatous, referring to a pathological divi- 
 sion. Though this classification is no longer used, a descrip- 
 tion of the two types (even at the expense of repetition) will 
 be a useful preface to the study of the special forms next to 
 be considered, explaining the variations in the intensity of the 
 process and the corresponding differences in visual damage. 
 
TYPES OF RETINITIS 255 
 
 The Simple or Serous Type (also known as (Edema of the 
 Retina) involves only the superficial layers and is slight in 
 degree, the evidences of inflammation being limited to 
 swelling, vascular distention, and occasionally hemorrhages. 
 Some authorities regard it, not as a distinct disease, but as 
 the first stage of the more common forms of retinitis. 
 
 There is limited impairment of vision (often merely a 
 blurred sensation), some distortion of images, and moderate 
 peripheral contraction of the field. The ophthalmoscope re- 
 veals a hazy fundus especially around the disc, the margins 
 of which are indistinct, veins somewhat dilated, tortuous, and 
 hidden in places by the oedema, and at times hemorrhages. 
 
 This form of retinitis may be due to excessive use of the 
 eyes, especially with uncorrected errors of refraction and by 
 poor illumination, the effect of intense light and heat, expo- 
 sure to cold, or there may be no assignable cause. It may be 
 merely the first stage of other forms of retinitis. 
 
 The prognosis is good when the affection remains of this 
 type and does not change to the deep form. Treatment con- 
 sists in the removal of the cause and the observance of the 
 directions given above. 
 
 The Deep or Parenchymatous Type is a more intense inflam- 
 mation involving the deeper layers of the retina; the patho- 
 logical changes are more extensive, including, besides those oc- 
 curring in the serous form, exudation, changes in the vessel walls, 
 and hemorrhages, and consequently capable of causing greater 
 destruction with atrophy and permanent visual damage. 
 
 There are often marked ocular discomfort, much disturbance 
 of vision and distortion of objects, peripheral contraction of 
 the field, and scotomata. The ophthalmoscope discloses, in 
 addition to the picture presented by the serous type, scattered 
 yellowish patches of exudate, especially in the macular re- 
 gion, changes in the walls of the blood-vessels, and hemorrhages. 
 
 This variety depends upon constitutional causes or repre- 
 sents an extension of or association with neighboring ocular 
 diseases. The prognosis is always serious; though some cases 
 recover with fair or even good vision, many are left with 
 marked impairment of this function. Treatment has been 
 
256 DISEASES OF THE RETINA 
 
 given under retinitis in general, and is discussed again in the 
 clinical forms of retinitis in the following pages. 
 
 ALBUMINURIC BETIITITIS 
 
 Retinitis of Bright's Disease {Renal Retinitis) presents oph- 
 thalmoscopic signs which are often pathognomonic. It is 
 usually bilateral, rarely unilateral. 
 
 Symptoms. — The subjective sjTnptoms are those of retinitis 
 in general (p. 253). The degree of disturbance of vision de- 
 pends upon the severity of the inflammation and especially 
 upon the position of the exudations and hemorrhages. Mi- 
 nutechanges in themacular region will cause considerablereduc- 
 tion in acuteness of vision, while extensive involvement of the 
 rest of the fundus may affect the sight comparatively little. 
 
 Ophthalmoscopic Signs (Plate XVI) are those of retinitis 
 in general: swelling and haziness of the retina and of the 
 papilla, distention and tortuosity of the retinal vessels, espe- 
 cially veins, and hemorrhages either in the form of flame- 
 shaped or round spots, or larger extravasations. To these 
 are added the distinctive feature: white spots found chiefly at 
 the macula and surrounding the disc, less frequently else- 
 where. At the macula, there may be at first merely a few 
 dots, but later there are more pronounced spots and these 
 are usually arranged in radiating lines which form a star- 
 shaped figure with the fovea for a centre; or when less com- 
 plete, the lines resemble the sticks of an open fan; they have 
 a certain brilliancy due to fatty degeneration of retinal ele- 
 ments and of exudation. Near the disc, and often more or 
 less surrounding it, are larger white spots; these may coalesce 
 and form a ring around the disc. 
 
 Though this is the most frequent picture of albuminuric 
 retinitis, there are other and less characteristic signs in 
 nephritis; there may be simply retinal hemorrhages, simple 
 retinitis, hemorrhagic retinitis, neuritis, or even a picture of 
 choked disc such as we are in the habit of associating with 
 cerebral tumor. On the other hand a brain tumor may pre- 
 sent ophthalmoscopic appearances identical with those of a 
 typical case of albuminuric retinitis. 
 
PLATE XVI 
 
 Fig. 234. — Albuminuric Retinitis. 
 
 Fig. 
 
 2.35. — All^uminurie Retinili.s wittl 
 More Pronounced C^hangcs. 
 
ALBUMINURIC RETINITIS 257 
 
 Albuminuric retinitis occurs under two forms: 1 , the inflamma- 
 tory, when swelling, congestion, and hemorrhages are the pre- 
 dominating features; and 2, the degenerative, when the white 
 spots and hemorrhages occur without swelling or congestion. 
 The two forms are usually associated in varying proportions. 
 
 Etiology. — The affection is usually a complication of 
 chronic interstitial nephritis ; much less frequently of chronic 
 parenchymatous nephritis; it may occur with any form of 
 nephritis, including that of scarlatina and pregnancy. From 
 one-quarter to one-half of all patients with nephritis present 
 some form of retinal lesion. 
 
 Pathology. — The retina presents oedema, hypertrophy of its 
 elements, deposits of fat and fibrin, and hemorrhages. The 
 retinal vessels are thickened and the seat of hyaline changes 
 with proliferation of the lining epithelium; these changes are 
 similar, to those taking place in the vessels of the kidney. The 
 spots in the macular region are (3aused by fatty degeneration 
 of exudate and retinal elements; their arrangement in a star- 
 shaped figure depends upon the disposition of Mueller's fibres 
 in this situation. 
 
 Course and Prognosis. — Though the retinitis is often a 
 late symptom of Bright's disease, the disturbance of vision 
 may be the first symptom which calls attention to the ne- 
 phritis; not infrequently the existence of nephritis is first dis- 
 covered through an ophthalmoscopic examination made in the 
 routine of prescribing glasses. There is no fixed relationship 
 between the course of the nephritis, the amount of albumin, 
 and the degree of retinitis. During the progress of the disease 
 there are often variations in the^ degree of disturbance of 
 vision, corresponding to the absorption and reappearance of 
 hemorrhages and exudates. The condition is of great prog- 
 nostic importance and indicates, with but few exceptions, a 
 fatal termination within two years; the exceptions are cases 
 occurring during pregnancy and scarlatina. 
 
 Treatment should be directed to the nephritis; no local 
 treatment is of any value. , 
 
 Albuminuric Retinitis in Pregnancy (Gravidic Retinitis) 
 complicates the albuminuria of pregnancy. The signs and 
 
258 DISEASES OF THE RETINA 
 
 symptoms are the same as in the other forms of albuminuric 
 retinitis (the inflammatory being the usual type), but they 
 tend to clear up after delivery. It usually occurs during the 
 final months of pregnancy, most frequently in primiparse, and 
 the prognosis in regard to vision is often good, especially if 
 labor be induced prematurely. When it occurs in the early 
 months, the prognosis is less favorable, and the condition 
 warrants the induction of abortion in order to save eyesight. 
 
 TJraeinic Amblyopia is the term used for loss of sight 
 during an attack of uraemia, without any changes in the retina. 
 It occurs in the course of nephritis, in pregnancy, and during 
 the late stages of scarlatina. Similar attacks may, of course, 
 also occur in patients who have albuminuric retinitis. It 
 appears suddenly, affects both eyes, and is associated with 
 other symptoms of urcemia: headache, vomiting, dyspnoea, 
 convulsions, and coma; the pupils are dilated but usually 
 respond to light. After lasting for a day or two, normal vision 
 returns, providing the patient recovers. The affection is not 
 retinal but cerebral, due to the retention of excretory sub- 
 stances in the blood. Treatment is that of uraemia. 
 
 Diabetic Retinitis occurs as a late manifestation of 
 diabetes, is usually bilateral, and is not so common as albu- 
 minuric retinitis. The ophthalmoscopic appearances (Plate 
 XVII) are characteristic: small, bright, white spots in and 
 around the macular region, grouped irregularly and not in the 
 form of a stellate figure; sometimes larger spots through 
 coalescence of the smaller ones; numerous punctate and occa- 
 sionally larger hemorrhages; there is no swelling of the optic 
 nerve or retina. Sometimes the picture resembles that of 
 albuminuric retinitis. The prognosis depends upon the sys- 
 temic condition. The treatment is that of diabetes. 
 
 Lieukaemic Retinitis presents swelling of the retina and 
 disc and numerous hemorrhages with greatly dilated and tor- 
 tuous vessels, the blood within which is of a very light color; 
 the entire fundus is pale red with a yellowish tinge. There 
 are white and yellqw spots of exudation, and some of these 
 may present a pink border; they consist of leucocytes sur- 
 rounded by red blood cells. 
 
PLATE XVII 
 
 Fig. 236. — Diabetic lletinitis. 
 
 Fig. 237. — Tlie Fundus in Amaurotic Family Idiocy. 
 
RETINITIS 259 
 
 SYPHILITIC RETINITIS 
 
 This is a common form, usually involves both eyes, and 
 occurs with acquired as well as with hereditary syphilis; in the 
 former, it is found in the secondary stage, during the first or 
 second year; in the latter, the lesions are not infrequently 
 seen after the subsidence of interstitial keratitis. It is gener- 
 ally associated with choroiditis (hence properly called Syph- 
 ilitic Choroidoretinitis) , and often with iritis. 
 
 Ophthalmoscopic Signs vary according to whether the 
 affection is due to acquired or hereditary syphilis. 
 
 In the acquired form, there is clouding of the fundus due to 
 swelling of the retina and disc, and to fine, dust-like opacities 
 of the posterior portion of the vitreous; these opacities cause 
 the disc to appear red and hazy; scattered grayish or white 
 spots often fringed with pigment, especially in the macular 
 region and in the periphery; circumscribed white exudations 
 along the large blood-vessels, forming white lines (Fig. 176, 
 Plate XIV); later, the deposits of pigment may be so pro- 
 nounced as to resemble somewhat the picture of retinitis 
 pigmentosa. The changes may be more circumscribed and 
 be represented principally by a large, white exudate, macular 
 or peripheral, changing later to an atrophic area with more 
 or less pigmentation. 
 
 In the hereditary form we find a leaden or brownish dis- 
 coloration of the fundus upon which are patches of pigment 
 of various shapes and reddish-yellow spots or gray or white 
 patches. All these lesions are most marked in the periphery. 
 
 Subjective Symptoms consist of more or less diminution in 
 the acuteness of vision, diminution in the light sense, night 
 blindness, annoying flashes of light, distortion and changes in 
 size of objects, central and ring scotomata, and later, contrac- 
 tion of the field of vision. 
 
 Course and Prognosis. — The progress is slow and the prog- 
 nosis depends upon the stage during which treatment is begun; 
 if begun early and carried out vigorously, the prognosis is 
 good, though some impairment of vjsion usually remains. 
 Neglected cases are often followed by atrophy of the retina 
 and optic nerve. 
 
260 DISEASES OF THE RETINA 
 
 Treatment consists in thorough use of mercury by inunc- 
 tion, iodide of potassium, rest of the eyes, protection from 
 light, and atropine. Salvarsan is often useful in the beginning 
 of the treatment. 
 
 Hemorrhagric Retinitis presents numerous and recur- 
 rent hemorrhages added to the other signs of retinitis; the 
 extravasations of blood, both flame-shaped (superficial) and 
 roundly irregular (deep), may be scattered all over the fun- 
 dus, or may be most abundant in the macular region or sur- 
 rounding the disc. This form is sometimes a variety of albu- 
 minuric retinitis. It usually occurs in elderly individuals as a 
 result of diseases of the heart and blood-vessels and other cir- 
 culatory disturbances; it may also be a local affection and be 
 due to changes in the retinal arteries and veins including 
 thrombosis. It may be monocular or bilateral. The prog- 
 nosis is unfavorable. New hemorrhages are apt to be added 
 to the residua of the old ones; sometimes the affection ter- 
 minates in glaucoma. It may be a foreruimer of cerebral 
 hemorrhage. Treatment consists in rest for the eyes, smoked 
 glasses, sometimes local abstraction of blood, ergot, and the 
 iodides. Constitutional treatment is of the greatest impor- 
 tance and enables the patient to profit from the warning of 
 danger of hemorrhages in other parts of the body. 
 
 Septic Retinitis {Metastatic Retinitis) results from the 
 lodgment of septic emboli in the retinal arteries in the course 
 of puerperal and other forms of septicaemia and pyaemia, and 
 also from infected wounds and foreign bodies. In the first 
 stage there are small white spots and hemorrhages around the 
 disc and in the macular region; very soon the uveal tract is 
 invaded and the signs of suppurative choroiditis (p. 186) ap- 
 pear. The inflammation ends in panophthalmitis or in de- 
 generation of the eyeball without perforation (pseudoglioma). 
 In rare instances the process does not spread to the uvea and 
 then the patient may recover with some vision. Non-infected 
 embolus gives rise to characteristic retinal changes (p. 264). 
 
 Uncomiuon Forms of Ketiual Changes. — ^A number 
 of uncommon pathological conditions are found in the retina 
 which have received names describing the clinical picture in 
 
UNCOMMON FORMS OF RETINAL CHANGES 261 
 
 each case. Among these are Retinitis Circinata, a more or 
 less complete circle of white spots or patches surrounding the 
 macula, probably the results of hemorrhages; Angioid 
 Streaks, dark-brown, pigmented striae resembling obliterated 
 blood-vessels, and probably the sequelae of hemorrhages; 
 Retinitis Striata, yellowish or white stripes, sometimes bor- 
 dered by pigment, radiating from the disc to the periphery, 
 either representing former hemorrhages or cured retinal de- 
 tachment; Retinitis Proliferans, dense, vascularized masses of 
 whitish connective tissue, which project from the retina into 
 the vitreous hiding the disc (p. -221); Hole in the Macula, a 
 deep red, round patch, with stippled centre, somewhat less in 
 size than the disc, situated at the macula and looking as if a 
 hole had been punched out, is occasionally the result of con- 
 tusion or concussion injury. 
 
 Retinal Changes due to Excessive Light are seen after in- 
 jurious exposure of the eye to the sun (solar retinitis), espe- 
 cially in watching an eclipse with insufficient protection, or 
 to electric light (electric retinitis), as in electric welding. 
 There are pigment changes at the macula and there may be 
 slight evidences of retinitis; the subjective s5Tnptoms arc 
 limited to a central, positive scotoma which may become less 
 marked, but does not disappear entirely, and some distortion 
 of objects. The conjunctivitis which results from exposure 
 to excessive light is described on p. 97. 
 
 Symmetrical Changes at the Macula in Infancy (Amaurotic 
 Family Idiocy) occur in infants with general muscular and 
 mental weakness and gradual loss of sight, ending fatally 
 within two years; it is bilateral; several children of the same 
 parents are sometimes attacked, and most cases are of Jewish 
 parentage. Ophthalmoscopically this resembles embolism of 
 the central artery: a dark red spot at the macula surroimded 
 by a grayish-white zone somewhat larger than the size of the 
 disc (Plate XVII) followed by optic-nerve atrophy. Histolog- 
 ically, changes in the pyramid cells of the cortex, and degenera- 
 tion of the cord and ganglion cells of the retina, are found. 
 
 Contusion of the Retina (Commotio Retince, (Edema of the 
 Retina) is a transient clouding resulting from a contusion of 
 
262 DISEASES OF THE RETINA 
 
 the eyeball. There is grayish cedema of the retina at the 
 macula and in the neighborhood of the papilla, sometimes also 
 at or opposite the contused spot. Some reduction in vision 
 and changes in the field are present, but disappear with the 
 subsidence of the oedema in a few days. Treatment consists 
 in rest of the eyes, smoked glasses, and atropine. 
 
 CIRCULATORY DISTURBANCES OF THE RETINA 
 
 H3rperaemia of the Retina, when slight, is recognized 
 by increased redness of the disc and by slight striation of its 
 margins; such a condition is often found in persons suffering 
 from the effects of errors of refraction (asthenopia) and in 
 those whose vocations expose the eye to excessive light or 
 heat. When marked, hyperffimia is an accompaniment of in- 
 flammation of the retina and of surrounding ocular struc- 
 tures. The condition may be either arterial or venous 
 in type. 
 
 Venous hyperoemia is seen as a result of local pressure, in 
 certain general diseases (especially heart disease), emphy- 
 sema, convulsions, and in most pronounced form in throm- 
 bosis of the central vein. A very marked example, called 
 Cyanosis of the Retina, is found in patients with congenital 
 heart disease and general cyanosis, presenting great disten- 
 tion of the blood-vessels, especially the veins, and a dark 
 color of the blood contained therein. 
 
 Anaemia of the Retina may be merely the ocular expres- 
 sion of a general condition, or it may be local; its onset may 
 be sudden or gradual. Acute anaemia, also known as Ischce- 
 mia of the Retina, may result from occlusion (embolism), 
 compression (sudden increase of tension), cardiac failure 
 (syncope, cholera), and vasomotor spasm; there are extreme 
 narrowing of the retinal asteries, pallor of the disc, and blind- 
 ness; examples due to vasomotor spasm are furnished by 
 quinine poisoning, in which some reduction of vision and some 
 contraction of the field are permanent (p. 286), and migraine, 
 in which the effects are transient. The chronic form occurs 
 with general anaemia and is frequently seen after retinal 
 disease, causing atrophy in which the vessels become narrow, 
 
CIRCULATORY DISTURBANCES OF THE RETINA 263 
 
 bordered by white lines of connective tissue, or even changed 
 into empty threads. 
 
 Hemorrhages in the Ketina often occur without any 
 signs of inflammation. 
 
 Objective Signs (Fig. 238, Plate XVIII).— Retinal hemor- 
 rhages vary in size, shape, and position; they are found most 
 frequently in the neighborhood of the larger blood-vessels and 
 also in the macular region. When situated in the nerve-fibre 
 layer, they have a striate or flame-shaped form; when deep, 
 they are rounded or irregular in outline. Sometimes a large, 
 round extravasation is seen in the region of the macula, be- 
 tween the retina and vitreous; this is known as asubhyaloid 
 (or preretinal) hemorrhage. Retinal hemorrhages become 
 absorbed slowly; the smaller ones may leave no traces; but 
 more frequently white spots, sometimes pigmented, indicate 
 their previous site. They, may be followed by glaucoma, 
 opacities of the vitreous, and occasionally by detachment of 
 the retina. 
 
 Subjective Symptoms. — Interference with vision depends 
 upon the size and particularly the situation of the hemor- 
 rhage; if at the macula, vision is much diminished. A scotoma 
 results if the retinal tissue has been injured. Subhyaloid 
 hemorrhage causes no permanent change in vision after ab- 
 sorption, since the retina is not involved. 
 
 Etiology .^The causes of retinal hemorrhages are: (1) In- 
 juries; (2) local disease of the vessels of the retina and cho- 
 roid; (3) cardiac (hypertrophy and valvular); (4) diseased 
 state of the blood-vessels, especially arteriosclerosis and athe- 
 roma, frequently associated with heart and kidney disease in 
 old persons, and often a warning of cerebral apoplexy; (5) 
 disturbances in the circulation (retinal embolism, thrombosis, 
 hemorrhages in the new-born, menstrual disturbances, and 
 after iridectomy in glaucoma) ; (6) changes in the composition 
 of the blood and in the walls of the blood-vessels, seen in 
 ansemia, pernicious anaemia, leukaemia, haemophilia, purpura, 
 scurvy, pyaemia and septicaemia, albuminuria, diabetes, ma- 
 larial fevers, jaimdice, poisons (phosphorus), etc.; (7) loss of 
 blood (haematemesis, menorrhagia, etc.). 
 
264 DISEASES OF THE RETINA 
 
 Treatment of the etiological factor is indicated. In addi- 
 tion, avoidance of exertion or excitement, rest of the eyes, 
 cardiac sedatives, iodides, and, if the blood-pressure is exces- 
 sive, nitroglycerin. 
 
 Changes in the Fundus in Arteriosclerosis are important 
 since they indicate similar lesions in other parts of the body, 
 especially the brain; ophthalmological evidence may be the 
 first to reveal the existence of this serious vascular lesion. 
 The fundus may present any or all of the following changes 
 (Fig. 239, Plate XVIII): Increased tortuosity and beaded 
 appearance of the blood-vessels; greater opacity of the arteries 
 and widening of the central light-streak (to a lesser extent 
 this applies also to the veins) ; interruption of continuity in the 
 veins where they are crossed j)y arteries, and dilatation just 
 beyond these points; white lines along the borders of vessels 
 due to degeneration and infiltration of the walls (perivas- 
 culitis) ; retinal cedema near disc, along blood-vessels, or scat- 
 tered in spots; hemorrhages, scattered or along blood-vessels. 
 
 Embolism of the Central Artery. — Obstruction of 
 the central artery of the retina by a nonAnfected embolus is of 
 infrequent occurrence; though- it causes sudden blindness, this 
 is sometimes unrecognized by the patient, because it is uni- 
 lateral and there is no pain. The left eye is the one generally 
 affected. 
 
 Objective Signs. — There are no external signs, but the oph- 
 thalmoscopic picture is very characteristic. Withia a few 
 hours, the fundus becomes pale and oedematous, grayish or 
 even milky; this is most pronoimced near the disc and macula 
 and fades out toward the periphery. In the situation of the 
 fovea there is a bright cherry-red spot which stands out in 
 marked contrast to the neighboring grayish-white retina; this 
 represents the normal red color of the choroid, here uncovered 
 by the inner layers of the retina and consequently by cedema. 
 The arteries are very thin and can be followed only a short 
 distance from the disc; beyond this point they may be lost 
 entirely. The veins also contain less than the normal amount 
 of blood and may present a beaded appearance. Occasion- 
 ally a few small hemorrhages are seen. Pressure upon the 
 
PLATE XVIII 
 
 Fig. 238. — H(Mii(irrh;iK*'.s in the Retina. 
 
 Fig. 239. — Changes; in the Fundus in Arteriosclei-o,sis. 
 
EMBOLISM OF THE CENTRAL ARTERY 265 
 
 eyeball gives rise to the appearance of broken columns of blood 
 with clear spaces between them, especially in the veins; this 
 intermittent blood-column is sometimes observed without 
 pressure. Occasionally the embolus can be seen, but usually 
 its presence is shown by a swelling in the artery, beyond which 
 the vessel is thin or obliterated. 
 
 After a few days, degeneration of the retina occurs, and at 
 the end of a few weeks atrophy. The oedema subsides, the 
 retina and disc atrophy, the latter becomes white with 
 sharply defined outUne, and the blood-vessels become 
 shrunken or are represented by white lines. 
 
 Subjective Symptoms. — There is sudden and complete blind- 
 ness; even perception of Ught is lost. Occasionally a small 
 part of the retina preserves its function; this occurs when 
 there are cilio-retinal vessels (an anastomosis between the 
 retinal and the short posterior ciliary arteries); this region 
 usually lies between the disc and the macula. 
 
 The foregoing description applies to cases in which the 
 main trunk of the central artery is occluded. The embolus 
 may, however, lodge in one of the branches of the central 
 artery. In such cases the interference with sight and the 
 changes in the background will be limited to the area sup- 
 plied by the occluded branch. 
 
 Etiology. — The condition is most frequently due to valvular 
 heart disease, less often to atheroma, aneurism of the aorta or 
 carotid, Bright's disease, and pregnancy. 
 
 A thrombus of the central artery may give rise to the same 
 signs and symptoms as embolism, and a differential diagnosis 
 is difficult or impossible. 
 
 Treatment is rarely effective. If the case is seen early, 
 inhalations of amyl nitrite, massage of the eyeball, and para- 
 centesis of the cornea may be employed for the purpose of 
 driving the plug along into one of the smaller branches, where 
 it will give rise to less serious results; in a few cases, such 
 treatment has been beneficial. 
 
 Thrombosis of the Central Vein may occur in old persons 
 with atheroma and cardiac disease; it also follows cellulitis 
 of the orbit. It is one of the causes of hemorrhagic retinitis. 
 
266 DISEASES OF THE RETINA 
 
 It may be complete or partial. There is diminution of vision, 
 either corresponding to the entire field, or if only a branch 
 is affected, to the part of the retina supplied by it. The 
 veins are greatly engorged and tortuous, the arteries very 
 small, there are numerous large hemorrhages, and indistinct- 
 ness of the margins of the disc. The condition usually ends 
 in atrophy of the retina and disc. There is no treatment. 
 
 PIGMENTARY DEGENERATION OF THE RETINA, OR 
 RETINITIS PIGMENTOSA 
 
 A chronic, progressive degeneration, consisting of atrophy of 
 the retina with characteristic deposits of pigment. 
 
 Subjective Symptoms. — Night blindness (nyctalopia), con- 
 centric contraction of the field of vision, progressive diminution 
 in sight, terminating in advanced years in complete blindness. 
 
 In early life there is but slight reduction in the extent of 
 the field with good illumination, and central vision is often 
 perfect. But with feeble illumination, the peripheral parts of 
 the retina do not react, and on this accoimt the patient cannot 
 find his way about at night, because the field is small. With 
 increasing years, the field becomes contracted even with good 
 illumination. Finally, in advanced life, central vision be- 
 comes poor, and gradually complete blindness follows. 
 
 Ophthalmoscopic Examination (Fig. 240, Plate XIX) shows 
 black spots in the periphery of the fundus; these have the 
 shape of branching cells, like bone corpuscles with connect- 
 ing processes, and are found especially along the blood-vessels; 
 they commence at the equator; in the com'se of years new 
 spots form, and in this way the pigment circle gradually ap- 
 proaches the disc and also increases its width towards the 
 periphery; the process is one of migration from the pigment 
 layer of the retina. The larger choroidal vesselh become 
 plainly visible on account of absorption and decoloration of 
 the retinal pigment. The disc and retina are atrophied; the 
 disc has a yellowish, waxy appearance. The retinal arteries 
 are very small and in the periphery are represented by mere 
 threads. Posterior cortical cataract often develops. 
 
 Atypical Forms. — There are cases of retinitis pigmentosa 
 
PLATE XIX 
 
 Fl«. 240. — Pigmentary D<'gfnorulioii of the iietina. 
 
 Fig. 241. — Detachment of the Retina. 
 
RETINITIS PIGMENTOSA 267 
 
 in which all the symptoms of this disease are present, and 
 the ophthalmoscope shows all changes except the presence of 
 pigment, and others in which the pigment is distributed in an 
 atypical manner and the spots are rounded or irregular 
 in shape. 
 
 Syphilitic choroidoretinitis may present a picture similar to 
 that of retinitis pigmentosa, but may be differentiated by the 
 patches of choroidal atrophy, the absence of characteristic 
 shape of the spots, their more irregular distribution and their 
 position beneath the blood-vessels, and by differences in the 
 character of the field. 
 
 A rare affection, similar to retinitis pigmentosa, having all 
 of its sjTnptoms except the pigmentation, is called Retinitis 
 Punctata Albescens; it presents a great number of small, 
 white spots scattered all over the fundus. 
 
 Occurrence. — The disease affects both eyes. It is either 
 congenital or develops in childhood. It is hereditary and is 
 often foimd in the offspring of consanguineous marriages; not 
 infrequently other congenital defects, such as deafness and 
 defective intelligence, are present. It may be comphcated 
 with other ocular anomalies. 
 
 Treatment is of no avail in arresting the progress. Gal- 
 vanism, strychnine, and iodides may be tried. 
 
 DETACHMENT OF THE RETINA 
 
 Retinal detachment (Ablatio Retinae, Amotio Retinw) is a 
 separation of the retina from the choroid. The name usually 
 refers to a separation by serum (seroiis detachment), but de- 
 tachment may also occur as a result of hemorrhage, exuda- 
 tion, or timaor. 
 
 Subjective Symptoms. — ^There is more or less complete loss 
 of vision in that part of the field which is opposite to the 
 detachment, causing the appearance of a dark cloud before 
 the eye and a corresponding limitation in the field as shown 
 with the perimeter; early symptoms are m^tamorphopsia and 
 flashes of light (photopsia). Central vision is preserved as 
 long as the macula is not included. 
 
 Ophthalmoscopic Signs depend upon the degree and extent 
 
268 DISEASES OF THE RETINA 
 
 of detachment. In addition to the other methods, the oph- 
 thalmoscope should be used at a distance. 
 
 When the detachment is flat, the retina appears but slightly 
 changed; it is somewhat cloudy and its vessels are dark and 
 tortuous; the variation in level of the affected portion can be 
 recognized by the difference in the refraction of a blood-vessel 
 on the separated part as compared with the rest of the fundus. 
 
 When the detachment is steep, as is generally the case, it is 
 usually found near the periphery. It is at first limited in ex- 
 tent {partial); it may commence at any part of the retina, 
 but as a result of sinking of the subretinal fluid it is usually 
 found hehw. It tends to enlarge and become complete, then 
 involving the entire retina, attached only at the disc and the 
 ora serrata. It presents a collection of grayish, bluish-gray, 
 or greenish folds (Fig. 241, Plate XIX) with white tops pre- 
 senting a bright sheen, projecting a variable distance into the 
 vitreous and shaking with movements of the eye. The blood- 
 vessels pass over and follow these folds and are therefore very 
 tortuous, and hidden at places; they appear prominent and of a 
 dark red, almost black color and smaller than normal. Some- 
 times a rupture can be seen in the separated retina through 
 which the choroid is visible. In the later stages, opacities of 
 the vitreous and cataract are often added. The rest of the 
 fundus presents a normal picture. Externally the eye appears 
 normal, but tension is usually lowered and the anterior cham- 
 ber deepened. 
 
 Etiology. — Detachment may be due to disease or injury; 
 occasionally no cause can be found. When due to disease, it 
 is most often found in myopia of high degree, and after ret- 
 initis, iridocyclitis, and iridochoroiditis; in such cases the 
 condition probably results from the shrinking of the organized 
 exudates in the vitreous, which thus pull the retina from its 
 attachment; it may also result from choroidal hemorrhage, 
 exudate, and sarcoma, in which instances the retina is pushed 
 forward. Traumatic detachment is usually the result of 
 blows, but occurs also after accidental or operative wounds, 
 especially when there has been loss of vitreous. 
 
 Diagnosis is readily made after ophthalmoscopic examina- 
 
DETACHMENT OF THE RETINA 269 
 
 tion and a study of the field ; but it is sometimes difficult to 
 decide whether the detachment is serous or due to sarcoma 
 of the choroid (p. 194). 
 
 Prognosis is unfavorable. The detachment tends to en- 
 large and to become complete. Even after improvement or 
 reattachment, relapses are the rule, and complete blindness is 
 the usual end. Rarely spontaneous reattachment occurs. 
 
 Treatment is sometimes followed by temporary improve- 
 ment, but is rarely productive of lasting benefit. In recent 
 cases, the best treatment is absolute rest in bed, atropine in the 
 affected eye, a firm bandage to both eyes, iodides and daily 
 injections of pilocarpine to produce sweating; this treatment 
 must be kept up for six or eight weeks. 
 
 Puncture of the sclera (posterior sclerotomy, p. 215) is fre- 
 quently resorted to and may, rarely, be successful. Subcon- 
 junctival injections of solution of sodium chloride, either of 
 physiological strength, or five or ten per cent., have proved 
 of value in occasional instances. 
 
 Trephining of the sclera over the seat of the detachment, 
 followed by aspiration of the subretinal fluid in this situa- 
 tion, has also been followed by an occasional cure. 
 
CHAPTER XIX 
 
 DISEASES OF THE OPTIC NERVE 
 
 Anatomy. — The optic nerve may be divided into (1) an intraocular 
 portion, the head of the optic nerve; (2) an orbilal portion extending 
 from the eyeball to the optic foramen; and (3) an intracranial portion 
 situated between the optic foramen and the chiasm. 
 
 The nerve pierces the sclera and choroid a Mttle to the inner side of 
 the posterior pole of the eyeball. At this point the outer layers of the 
 sclera become continuous with the sheaths of the nerve, while the inner 
 layers together with a few bands from the choroid stretch across the 
 foramen, presenting numerous openings for the passage of the separate 
 bundles of the optic nerve; this sieve-Uke arrangement is known as the 
 lamina crihrosa. Here the nerve fibres lose their medullary layer and 
 become transparent. Spreading apart before reaching the level of the 
 retina, they leave a funnel-shaped depression at the middle of the disc 
 (Fig. 43), the physiological excavation. 
 
 The lamina crihrosa represents the weakest portion of the layers of 
 the eyeball, and in increased tension is the first to recede. It surrounds 
 the bundles of the optic nerve with fibrous rings of connective tissue, 
 which serve as constricting bands when swelling occurs. 
 
 The orbital ■portion of the optic nerve presents a sigmoid curve per- 
 mitting free movement of the eyeball. The nerve consists of bundles 
 of nerve fibres separated by connective-tissue septa; between these 
 there are lymph spaces. The optic nerve is surrounded by three sheaths 
 originating from the' three envelopes of the brain, and known as the 
 pial, arachnoid, and dural sheaths; between the pial and the dural 
 sheaths is a space, the intervaginal space, divided into two parts by 
 the arachnoid sheath. The two spaces thus formed are lymph spaces; 
 they are lined by endothelium, and communicate with the correspond- 
 ing cerebral spaces. A&teriorly, the intervaginal space ends in a blind 
 extremity and the sheaths unite with the sclera. 
 
 A short distance from the eyeball, the central artery (a branch of the 
 ophthalmic) enters, and the central vein emerges; the latter empties into 
 the superior ophthalmic vein or directly into the cavernous sinus. 
 
 The intracranial portion of the optic nerve is short and flattened. 
 The optic foramen forms an unyielding ring which compresses the 
 nerve in inflammation and injury. 
 
 Affections of the Optic Nerve comprise (1) hyperaemia, (2) 
 infiammation, (3) atrophy, and (4) tumors (very rare) 
 
 270 
 
INFLAMMATION OF THE OPTIC NERVE 271 
 
 Hyperaemia or Congestion of the Optic Disc. — The 
 
 normal disc varies greatly in color; hence it is often difficult 
 to decide whetiier the papilla is congested or not. Hy- 
 persemia shows itself in increased redness due to capillary 
 injection, slight blurring and striation of the margins of the 
 disc often limited to a portion of the circumference, espe- 
 cially the nasal side, and some dilatation and tortuosity of the 
 retinal vessels. 
 
 Such a picture is frequently presented in eye strain from 
 hjqjeropia and astigmatism, excessive use of the eyes, espe- 
 cially with, insufficient or excessive light, and after lengthy 
 exposure to glare and heat. It is also foimd with inflamma- 
 tions of the deeper portions of the eyeball, or as the incipient 
 stage of optic neuritis, and occasionally as a congenital 
 anomaly. 
 
 When pronounced in degree, whether congenital or due to 
 the above-mentioned causes, this condition is often called 
 Pseudoneuritis . 
 
 Inflammation of the Optic Nerve, known as Optic Neuritis, 
 is divided into: 
 
 1. Intraocular Optic Neuritis, in which the head of the 
 optic nerve is the part affected, and in which there are marked 
 visible changes in the disc. 
 
 2. Retrobulbar Neuritis affecting the nerve behind the eye- 
 ball, in which disc changes are slight or absent, and their 
 existence is inferred from subjective symptoms. 
 
 INTRAOCTJLAB, OPTIC NEURITIS 
 
 This affection is also known as Descending Neuritis, Papil- 
 litis, Choked Disc, and Papilloedema. These names are often 
 used interchangeably and much confusion in regard to the 
 exact meaning of each has arisen in consequence. They do 
 not represent identical ophthalmoscopic pictures. It will be 
 convenient to describe the symptoms of this disease in gen- 
 eral, and then to consider the clinical forms for which each 
 of these names is a suitable title. 
 
 Ss^mptoms. — There is disturbance of vision, sometimes in- 
 significant, often considerable, but not always proportionate 
 
272 
 
 DISEASES OF THE OPTIC NERVE 
 
 to the degree of changes as revealed by the ophthalmoscope; 
 
 there may be complete blindness. The field of vision is 
 
 usually contracted peripherally, especially for colors; there 
 
 may be reversal of the color fields; the blind spot is enlarged; 
 
 there may be hemianopsia or scotomata. There is no pain, 
 
 and there are no external signs. 
 
 Ophthalmoscopic Signs. — The disc is swollen, projecting 
 
 (Fig. 242 and Plate XX), enlarged, of whitish or gray color 
 with reddish centre, striated, and often 
 presents white spots and hemorrhages; 
 its situation is recognized only by the 
 convergence of the retinal blood-ves- 
 sels, its margins having become indis- 
 tinguishable. The retinal vessels are 
 altered and seem interrupted where 
 they are covered by the swelling; the 
 arteries are thin, the veins much dis- 
 tended and very tortuoiLS. The ad- 
 jacent retina is cedematous, congested, 
 and presents white patches and hem- 
 orrhages. 
 
 Clinical Forms. — We recognize three 
 tjrpes of intraocular neuritis: 
 
 1. Choked Disc or Papillaedema, in 
 
 pearances; the lower half, ^^^^ ^^^ Condition is SUggestivC of 
 a longitudinal section. °° 
 
 compression causing cedema and en- 
 gorgement without inflammation, and the picture is the fol- 
 lowing: Great swelling and protrusion of the disc, marked 
 distortion and tortuosity of the retinal veins, and hemor- 
 rhages upon and near the cedematous papilla; the lesions 
 are limited rather sharply to the disc and the surrounding 
 retina is scarcely changed (Fig. 244, Plate XX). 
 
 2. Descending Neuritis, in which the appearances indicate 
 inflammation, and consist of hyperaemia and moderate swell- 
 ing of the disc with some exudate covering the surface and 
 margins, and slight fulness of the veins; thf process is not 
 limited to the disc but extends to the adjacent retina. 
 
 3. Neuroretinitis, when there are added to the signs of 
 
 Fig. 242. — Choked Disc. The 
 upper portion represents 
 the ophthalmoscopic ap- 
 
PLATE XX 
 
 Flc 243- Xcuroretinitis. 
 
 Fig. 244.— Clioked Disc. 
 
INTRAOCULAR OPTIC NEURITIS 273 
 
 neuritis just given, evidences that the retina is extensively 
 involved, such as hemorrhages along the retinal vessels and 
 spots of exudate and degeneration. 
 
 Papillitis is a name proposed to cover all forms of intra- 
 ocular neuritis, but is generally used as a synonym for neuritis. 
 
 Though it is convenient to recognize these clinical forms, 
 it must be remembered that in many cases no sharp line can 
 be drawn between these three types, either from the stand- 
 point of pathology or etiology, and that transition forms occur 
 frequently. 
 
 Course and Prognosis. — Though sometimes rapid, the 
 course is usually chronic, extending over many months. The 
 changes may subside and the disc may regain its normal 
 appearance with the preservation of good sight (especially 
 in syphilitic cases), and in others in which the cause of the 
 affection is removed before the process has advanced too far 
 or lasted too long. But in many instances intraocular neu- 
 ritis is followed by Postneuritic Atrophy: The disc becomes 
 white or grayish-white, its margins irregular, and surroxmded 
 by changes in the choroid, while the exudation changes into 
 coimective tissue which covers t^e lamina cribrosa; the 
 blood-vessels are contracted, the veins preserving some of 
 their tortuosity, and are frequently bordered by white lines 
 (Fig. 247, Plate XXI). The prognosis is, therefore, always 
 serious; when the course is unchecked, vision is finally either 
 much impaired or lost. The affection is usually bilateral, but 
 one eye may be affected before the other. 
 
 Etiology. — The causes are: diseases of the brain and its 
 envelopes; syphilis; general diseases; anaemia, either simple, 
 or the acute form due to loss of blood; diseases of menstrua- 
 tion; nasal accessory sinus disease; lead poisoning; heredity; 
 idiopathic (when no cause can be foimd); and orbital and 
 periorbital affections. 
 
 Brain Tumor is the most frequent cause; papillitis occurs 
 in 90 per cent, and then most often assumes the choked disc 
 type; the papilloedema may be the first symptom of the intra- 
 cranial growth. The occurrence or degree of papillitis de- 
 pends to a certain extent only upon the size or the situation 
 
274 DISEASES OF THE OPTIC NERVE 
 
 of the tumor; the greater swelling is most often on the same 
 side as the tumor, but there are many exceptions to this; it is 
 often most marked with cerebellar tumors. Occasionally it 
 gives rise to a picture resembling that of albuminuric retinitis 
 with its star-shaped figure at the macula. 
 
 Next in frequency comes meningitis, especially basilar and 
 tuberculous; in such cases the papillitis is apt to be of the 
 descending neuritis type. Then come abscess, hydrocepha- 
 lus, and enlarged pituitary body in acromegaly. 
 
 Syphilis is a frequent cause, and acts either by direct im- 
 plication or through the development of specific affection in 
 the cranial or orbital cavities. 
 
 Acute infective diseases (influenza, measles, scarlatina, 
 diphtheria, typhoid, erysipelas) are occasional causes. Gen- 
 eral affections, such as rheumatism, malaria, nephritis, and 
 arterial disease, are sometimes responsible; also deformities 
 of the skuU (oxycephalic) and, possibly, exposure to cdld. 
 
 Orbital and periorbital affections include inflammations of 
 the orbit, tumors of the orbit and optic nerve, and disease of 
 the nasal accessory sinuses and dental disease; these con- 
 stitute the examples of unilateral cases. 
 
 Pathology. — There are swelling, exudation of leucocytes, 
 venous engorgement, hemorrhage,, and distention of the in- 
 tervaginal space. Though numerous hypotheses have been 
 advanced to explain the production of choked disc, the exact 
 mechanism is still unsettled. At present it is generally be- 
 lieved to be due to increased intracranial pressure forcing 
 cerebro-spinal fluid into the intervaginal space of the optic 
 nerve, causing stasis in the region of the lamina cribrosa and 
 compression of the vessels, resulting in venous engorgement 
 and oedema. But it is also conceded that secondary factors, 
 such as direct transmission of inflammation from the brain 
 and excitation by irritating substances {toxins), may be 
 operative. 
 
 Treatment is directed against the cause. In syphilis, an 
 initial injection of salvarsan, followed by mercurialization and 
 later by the iodides; even in non-specific cases, mercury is 
 often of much value. Orbital and periorbital affections re- 
 
CHOKED DISC 275 
 
 quire appropriate surgical treatment. Locally, rest of the 
 eyes, shading from light, and sometimes abstraction of blood 
 from the mastoid region, are indicated. 
 
 Cerebral Decompression is frequently undertaken to reheve 
 the intracranial pressure responsible for choked disc, thus 
 enabling the optic nerves to resume their functions. In 
 most cases this operation causes a subsidence of the papillary 
 swelling and an improvement in vision, especially if it be re- 
 sorted to before much degenerative change in the nerves has 
 taken place; incidentally other symptoms of tumor of the 
 brain are relieved and life is prolonged. The operation is 
 performed in the right temporal region for pretentorial 
 growths; but when the tumor is subtentorial, the opening is 
 made in the suboccipital region. 
 
 Retrobulbar Neuritis (Orbital Optic Neuritis) involves the 
 orbital portion of the optic nerve, the process being an inter- 
 stitial neuritis. At first there are few or no visible changes 
 in the disc, and the diagnosis is made from the disturbance 
 of vision. Only the papillo-macular fibres of the optic nerve 
 are affected and consequently the change in the field of 
 vision takes the form of a central scotoma, often relative. 
 There are two forms, aciite and chronic. 
 
 ACUTE RETROBUIiBAB NEURITIS 
 
 This rather uncommon affection is generally unilateral, 
 occasionally bilateral. 
 
 Symptoms. — Severe headache on the same side, pain in 
 the orbit aggravated by movements of the eye and upon 
 pressing the eye backward. With these symptoms there is 
 rapid impairment of sight, beginning in the centre of the field 
 and progressing in the course of a week to partial or com- 
 plete blindness. Externally the eye appears normal. 
 
 Ophthalmoscopic Signs. — At first there are no changes; 
 later there may be slight hyperemia of the disc and haziness 
 of its margins, with distention and sometimes diminished 
 calibre of the retinal vessels. 
 
 Course. — The disease runs an acute course, and after a 
 
276 
 
 DISEASES OF THE OPTIC NERVE 
 
 month or two, if properly treated, the sight usually becomes 
 normal; or the cure is partial, and a central scotoma remains; 
 rarely it terminates in permanent and total blindness. Re- 
 lapses are sometimes observed. 
 
 Etiology. — Infection from neighboring parts {accessory si- 
 nuses of the nose) or oral sepsis (teeth, tonsils) ; direct extension 
 from the orbit (cellulitis, periostitis) ; general diseases {syphilis, 
 rheumatism) ; acute infectious diseases {influenza) ; poisons 
 (alcohol, lead); menstrual disturbances; disseminated scler- 
 osis; exposure to cold; sometimes no cause can be found. 
 
 Treatment. — Treatment of the cause. Diaphoresis; potas- 
 sic iodide and mercury; also strychnine. 
 
 CHBOITIC BETBOBULBAB. NETTBITIS 
 TOXIC, TOBACCO, OB ALCOHOL AMBLTOPLA, 
 
 A chronic affection of the orbital portion of the optic nerve, 
 oi frequent occurrence, usually attaclcing hoth eyes, and due in 
 the great majority of cases to excessive indulgence in tobacco, 
 alcohol, or hoth combined. 
 
 Symptoms. — There is gradual diminution in acuteness of 
 sight; foggy vision; the patient sees better in the evening and 
 the visual disturbance is more marked 
 in bright light. The field of vision 
 presents the normal peripheral boun- 
 dary, but there is a central color sco- 
 toma for red and green (Fig. 245), 
 corresponding to the distribution of 
 the papillo-macular fibres of the optic 
 nerve; the color defect is more marked 
 for green than for red; sometimes the 
 scotoma becomes absolute. 
 
 Ophthalmoscopic Signs. — ^At first 
 there are no changes in the papilla, 
 or merely slight hypersemia; later, there is very often a, pal- 
 lor of the temporal side of the disc. 
 
 Course and Prognosis. — The progress of the disease is slow. 
 If poisoning continues, vision becomes more impaired, may be 
 much reduced, or even lost. If the patient stops the use of 
 
 Fig. 245.— The Field of 
 Vision in Toxic Amblyopia 
 showing Central Color Sco- 
 toma. 
 
PLATR XXI 
 
 Flij. 1240. -SinipU' Atrophy of the Optic Nerve. 
 
 Fiu. 247. — I'ost-Ncuritic .\tiophy of the Optic Nerve. 
 
TOXIC AMBLYOPIA 277 
 
 the toxic material, there is usually gradvxd improvement and 
 sight is often restored to the normal, with complete disap- 
 pearance of the scotoma. Bjit in severe cases, there may be 
 some permanent reduction in the acuteness of vision, and the 
 relative scotoma may be permanent. 
 
 Etiology. — The condition results most frequently from 
 over indulgence in tobacco whether in smoking or chewing, 
 occasionally after snuff-taking. The stronger tobaccos used 
 in cigars and pipes are the forms which are most frequently 
 responsible. Certain individuals are more susceptible than 
 others. Impairment of the general health predisposes, as 
 does also the practice of smoking when the stomach is empty. 
 It occurs almost exclusively in middle-aged or elderly men. 
 Alcohol also constitutes a very frequent cause; in most cases 
 both alcohol and tobacco act together. Other poisons which in 
 toxic doses may cause similar amblyopia are chloral, iodo- 
 form, lead, arsenic, the toxin of diabetes, bisulphide of car- 
 bon, nitrobenzol, and anilin. 
 
 Pathology. — The process consists of a degeneration of the 
 ganglion cells in the macular region with interstitial neuritis 
 of the papillo-macular bundle in the optic nerve, and subse- 
 quent degeneration of these fibres. 
 
 Treatment consists in abstinence from tobacco and alcohol; 
 this is the most important part of the treatment. Sweating 
 by various means, large quantities of water taken between 
 meals, and moderate doses of potassic iodide will prove effec- 
 tive. Later strychnine is prescribed in increasing doses, up 
 to the limit of tolerance. 
 
 ATROPHT OF THE OPTIC NEBVE 
 
 This affection occurs either (1) as a primary disease (simple, 
 gray, non-inflammntory, or progressive atrophy) or (2) second- 
 ary to some other affection of the nerve or retina {neuritic, 
 postpapillitic, or inflammatory atrophy); in the latter class 
 belong also retinitic and choroiditic atrophy. 
 
 Symptoms. — There are reduction in the acuteness of vision, 
 concentric contraction or irregular or sector-shaped peripheral 
 defects of the field (Fig. 248), first for colors and then for form, 
 
278 DISEASES OF THE OPTIC NERVE 
 
 diminution in the light sense, sometimes scotomata, and color 
 blindness (first for green, then for red, then for blue). These 
 symptoms tend to progress and end in complete blindness. 
 
 Ophthalmoscopic Signs depend somewhat upon whether 
 the type is primary or secondary: 
 
 Primary Atrophy (Fig. 246, Plate XXI) : The disc is white, 
 grayish, or bluish-white, its edges are sharply defined and 
 
 regular, its size is somewhat dimin- 
 ished, and it presents a saucer- 
 shaped excavation (Fig. 186); the 
 lamina cribrosa is often seen very 
 plainly; the minute vessels of the 
 disc have disappeared; the retinal 
 vessels may appear normal or the 
 arteries may be diminishedin calibre. 
 Postpapillitic Atrophy (Fig. 247, 
 
 Fig. 248.— Marked Concentric Plate XXI) : The disC is denSB whltC 
 
 a bluish tint, its margins irregular 
 and somewhat hazy, its minute vessels lost, and it is covered 
 by connective tissue resulting from the organization of the 
 previous exudate; on this account the lamina cribrosa is 
 hidden; the retinal arteries are narrow, the veins normal in 
 size or distended and generally tortuous, and both sets are 
 apt to be enclosed by white lines. 
 
 Retinitic and Choroiditic Atrophy: The disc has a grayish- 
 red or yellow, waxy appearance (Fig. 240, Plate XIX), its 
 outlines are somewhat indistinct, the vessels are exceedingly 
 narrow and many disappear entirely, and the retina presents 
 evidences of the antecedent choroiditis or retinitis. 
 
 After a time, the differences in the appearances of simple 
 and postneuritic atrophy become much less marked. 
 
 It should be borne in mind that the disc varies in color in 
 health and may appear atrophied as the result of congenital or 
 senile peculiarities, although vision is normal and the field 
 perfect; hence the diagnosis in many cases cannot be made 
 from the ophthalmoscopic signs alone, especially when these 
 signs are not pronounced. 
 
ATROPHY OF THE OPTIC NERVE 279 
 
 Etiology. — Simple atrophy is frequently due to spinal dis- 
 eases, especially locomotor ataxia, developing as an early 
 symptom in one-third of the cases of this affection. It is 
 common also in affections of the brain, especially disseminated 
 sclerosis, general paralysis of the insane, and tumors. It may 
 also be due to syphilis, malaria, diabetes, acromegaly, im- 
 paired nutrition, arteriosclerosis, and certain poisons (includ- 
 ing wood-alcohol) . Occasionally it is hereditary, and in some 
 cases no cause can be found. Hereditary cases occur in young 
 adult males, involve the papillo-macular bundle, are accom- 
 panied by central scotoma, and the affection is known as 
 Leber's Disease. 
 
 Secondary atrophy follows choked disc, descending neu- 
 ritis, pigmentary degeneration of the retina, and embolism 
 and thrombosis of the central artery; it may also be con- 
 secutive to choroiditis, retinitis, glaucoma, hypophysis disease, 
 and orbital inflammations. It may result from injury to the 
 optic nerve due to fracture of the orbital canal, following a 
 blow or other violence; in such cases the atrophy does not 
 show itself for a number of weeks, though reduction of vision 
 and contraction of the field or even blindness ensues im- 
 mediately. 
 
 Pathology. — The process consists of increase in the inter- 
 stitial connective tissue with atrophy and disappearance of 
 the nerve fibres. 
 
 Course and Prognosis. — The affection occurs chiefly in 
 middle life, the course is slow extending over many months, 
 and the prognosis is usually unfavorable. Simple atrophy 
 generally progresses to absolute blindness. In secondary 
 atrophy the prognosis is better, and depends upon the extent 
 to which the optic nerve has escaped from the destructive 
 influences of the preceding processes. 
 
 Treatment consists in attempting to control the cav^e of 
 the atrophy. For the atrophy itself very little can be done. 
 Potassium iodide, strychnine hypodermically, mercury, 
 nitroglycerin, galvanism, and the high-frequency current are 
 the remedies most frequently employed; these should be 
 tried but one must not expect much benefit. 
 
CHAPTER XX 
 
 AMBLYOPIA, AMAUROSIS, AND DISTURBANCES 
 OF VISION WITHOUT APPARENT CHANGES 
 
 Amblyopia is a reduction in the acuteness of vision which 
 cannot be relieved by glasses and which is not dependent 
 upon any visible changes in the eye. The term is sometimes 
 used in a less restricted feense to designate poor sight, even 
 when changes are found in the eye, as, for instance, toxic 
 amblyopia in which temporal pallor of the disc exists. 
 
 Amaurosis is the name applied to absolute blindness when 
 unaccompanied by discoverable ocular changes; the use of 
 this term is, however, sometimes extended so as to comprise 
 all cases of absolute blindness, including those which show 
 ophthalmoscopic or external changes. 
 
 CONGENITAL AMBLYOPIA AND AMBLYOPIA EX 
 ANOPSIA 
 
 Congenitally defective vision usually affects one eye; it is 
 frequently associated with high degrees of hyperopia and 
 astigmatism. Probably in many of the so-called congenital 
 cases, the amblyopia is really acquired — the errors of refrac- 
 tion have prevented perfect images from being focussed on 
 the retina, and this lack of training has caused poor vision. 
 The most careful correction of the error of refraction fails to 
 produce normal vision; in young patients, however, the sight 
 can frequently be improved or brought up to the normal 
 after suitable glasses have been worn for a time. 
 
 Amblyopia ex Anopsia. — Any interference with vision, 
 either congenital or dating from early life, which prevents 
 perfect focussing upon the retina, such as cataract and cor- 
 neal opacity, causes amblyopia from non-use; hence the 
 advisability of operating upon congenital and infantile cata- 
 racts early. An obstacle to vision beginning nfter the age of 
 
 280 
 
CONGENITAL AMBLYOPIA 281 
 
 seven or eight years does not usually interfere with the func- 
 tional activity of the retina. 
 
 Unilateral amblyopia predisposes to squint by lessening the 
 value of binocular vision. Very commonly amblyopia de- 
 velops in an eye which has squinted from early life on account 
 of its exclusion from the visual act, the retinal image in this 
 eye being suppressed (p. 375). Exercise of such an eye before 
 the end of the sixth year, by forcing it to work while the sound 
 eye is covered or atropinized, will frequently improve its 
 visual power. Bilateral amblyopia is nearly always associ- 
 ated with nystagmus. 
 
 Congenital Word-Blindness is met with not infrequently, 
 especially in boys, and is supposed to be due to a defect in 
 the visual memory centre for words and letters. The defect 
 consists in an inability or difficulty in reading and spelling. 
 If detected early in life, much improvement can be effected 
 by training. 
 
 CONGENITAL COLOR AMBLYOPLA. 
 
 Congenital Color-Blindness occurs in from 3 to 4 per cent, 
 of males and in only 0.3 per cent, of females. It generally 
 affects both eyes, is often hereditary, and the functions of 
 the eyes are otherwise normal. The cause and pathology 
 are unknown; the defect is incurable, but the color sense can 
 be developed, if training is begun at a sufficiently early period 
 of life. The condition is usually a partial achromatopsia — a 
 loss of perception of one or two of the fundamental colors 
 (red, green, and blue). The absence of all appreciation of 
 colors {total achromatopsia) is very rare as a congenital defect, 
 though it is not uncommon in acquired color blindness occur- 
 ring in optic-nerve atrophy. 
 
 Theories of Color Perception and Color Defects. — A number of 
 theories have been advanced to explain color vision and its derange- 
 ments. The principal ones are those of Young-Helmholtz, Bering, and 
 Edridge-GreeB. 
 
 (1) The Young-Helmholtz Theory assumes that there are three sets 
 of color-perceiving elements in the retina, each of which, if stimulated 
 alone, would give rise to the sensation of one of the three fundamental 
 colors — red, green, and violet; and that all other colors arise from com- 
 
282 DISTURBANCES OF VISION 
 
 binations of these. With a defect of one of these primary perceptions, 
 a color win be seen as if composed of the remaining two only. Ac- 
 cording to the color which is deficient, the patient is said to be red- 
 blind, green-blind, or violet-blind. The more commonly recognized 
 forms are red blindness, green blindness, and red-green blindness. 
 
 (2) TTie Hering Theory is that the color sense depends upon chemical 
 changes in three different visual substances in the retina — white- 
 black, red-green, and blue-yellow, by the decomposition and restora- 
 tion of which substances the sensations of color are produced; for 
 instance, red Ught produces destruction in the red-green substance and 
 thus the sensation of red; green Ught causes a restoration in the red- 
 green substance and thus the sensation of green. According to this 
 theory, color blindness is caused by the absence of one or two of these 
 visual substances; if one is absent, the patient is either red-green 
 (frequent), or blue-yellow (rare) bhnd; if two are absent, nothing but the 
 white-black substance is left, and the patient has total color-bUndness, 
 everything appearing gray. 
 
 (3) The Edridge-Green Theory supposes that a photograph is formed 
 in the retina by decomposition of the visual purple in the rods; this 
 chemically stimulates the ends of the cones, causing a visual impulse to 
 be transmitted through the optic-nerve fibres to the brain. It assumes 
 that this impulse differs in quahty according to the wave-length (color) 
 of the rays of light producing it, and that there is a special centre in the 
 brain to distinguish these differences. Edridge-Green describes two 
 distinct kinds of color bhndness: (a) an inabiUty to perceive certain 
 rays of the spectrum, the latter being shortened at one or both ends, 
 e.g., a red-blind person will say that he sees no hght at all when shown a 
 pure red light by means of a lantern; (b) a defect in the power of distin- 
 guishing differences of wave-length (color) of light, though the light 
 itself is perceived. 
 
 Tests for Color Vision are particularly useful in the exami- 
 nation of employees in certain occupations in which perfect 
 color perception is essential. This is of especial importance 
 in the railway and steamship service, in which the most com- 
 monly used signals are red and green, the colors in which most 
 color-blind persons are defective. 
 
 The most common and convenient method of examination 
 is Holmgren's Test with a large assortment of colored wor- 
 steds. This collection consists of (1) certain colors called 
 "test colors " (a pale green, a light -pink, and a bright red), 
 (2) lighter tints and darker shades of these colors {"match 
 colors") and (3) "confusion colors" (yellow, brown, gray, 
 drab, fawn, mauve, pale blue, etc.), hues which experience 
 
CONGENITAL COLOR AMBLYOPIA 283 
 
 has shown that the color-bHnd individual will select as match- 
 ing the test colors, but which appear entirely different to the 
 normal eye. The test must be made in good daylight. 
 
 The pale-green sample is given to the individual and he is 
 required to select colors which match the test sample; if he 
 does this correctly, he has normal color sense. If he not 
 only selects similar colors but also confusion colors, and in 
 addition shows a certain hesitancy, his color sense is 
 defective. 
 
 Next a pink skein is selected and the person examined is 
 asked to match this. If besides similar skeins he also selects 
 blue or violet, he is red-blind; if he selects green or gray, he 
 is green-blind. 
 
 Finally, the bright-red test skein is given to the indij^idual 
 for matching. If, besides reds, he chooses green and brown 
 colors darker than the red, he is red-blind; if he selects shades 
 of those colors lighter than the red, he is green-blind. 
 
 Edridge-Green uses four test colors (orange, violet, blue- 
 green, and red) in skeins of colored wool and in a lantern 
 with colored glasses. The person examined is required to 
 name and to match the four test colors. 
 
 The skeins of colored worsteds have been collected upon 
 a stick (Thomson's Test) and numbered, so as to facilitate 
 testing of employees and the record of their examinations. 
 Railroad and steamship men are often tested by Color Test 
 Lanterns (Thomson's, Williams', Edridge-Green's) in which 
 colored discs are slid in front of an aperture; over these 
 smoked glass can be placed, so as to imitate the appear- 
 ance of signal lights under all conditions of weather and 
 atmosphere. 
 
 The spectroscope is also employed for testing the color sense. 
 
 Acquired Color Blindness is often found as a symptom of 
 diseases of the retina and optic nerve. It is generally present 
 in optic-nerve atrophy when vision is markedly impaired. 
 
 Colored Vision is occasionally complained of by patients 
 with or without changes in the retina. The most frequent 
 form is red vision (Erythropsia) after cataract extraction* 
 Rarely green, blue, yellow, or white vision is met with. 
 
284 DISTURBANCES OF VISION 
 
 HYSTEKICAX AMBLTOPIA 
 
 This affection usually occurs in young girls and women, 
 occasionally in young persons of the male sex, and is most 
 often unilateral. 
 
 Symptoms. — The most constant symptom is a diminution 
 in the acuteness of vision which frequently amounts to com- 
 plete blindness. The field of vision is contracted concentri- 
 cally, both for white and colors; it may be tubular; since the 
 retina becomes exhausted rapidly, this limitation may become 
 more marked with each succeeding test during the same 
 examination. The color fields have not the same relative 
 areas as with the normal eye; they may- be larger than that 
 for white; their order is often reversed — i.e., green the largest, 
 red q^xt, and blue the smallest. There may be central, an- 
 nular, or irregular scotomata or hemianopsia. A great variety 
 of other ocular symptoms may be present, such as photo- 
 phobia, flashes of Ught, blepharospasm, corneal ansesthesia, 
 monocular diplopia, ptosis, and metamorphopsia. The pupil- 
 lary reflexes and ophthalmoscopic appearances are normal. 
 
 With these ocular manifestations there are usually other 
 hysterical symptoms, especially hemiansesthesia of the affected 
 side. It is sometimes difficult to distinguish between this 
 affection and malingering. It sometimes follows injuries 
 (traumatic neurosis) even when these do not involve the eye. 
 
 Prognosis is good, but the affection may last many months. 
 
 Treatment is directed to the hysterical condition. Locally, 
 electricity, massage, and hypodermic injection of strychnine 
 are productive of good results, probably through psychic or 
 suggestive influences. 
 
 SIKTTLATES AHBLYOPIA 
 
 Patients sometimes pretend to be blind in one eye in order 
 to escape military duty or to recover damages for alleged 
 injury; occasionally bilateral blindness is simulated. The 
 detection of pretended monocular blindness is usually easy, 
 but occasionally difficult. The following tests may be 
 •employed: 
 
 Tests. — 1. Place a lighted candle fifteen or twenty feet in 
 
SIMULATED AMBLYOPIA 285 
 
 front of the patient and put a prism of 6°, base upward or 
 downward, before the sound eye; if the patient sees double it 
 is an indication that the vision is good in both eyes. 
 
 2. With the lighted candle in the same position, cover up 
 the supposed blind eye. Then produce monocular diplopia 
 by moving a 6° prism, base upward or downward, until the 
 apex corresponds to the centre of the pupil. Next uncover 
 the blind eye and at the same time move the prism until it 
 covers the entire pupil. If now there is still double vision 
 (binocular diplopia) it is evident that both eyes see. 
 
 3. Place a strong convex lens (12 D.) before the good eye 
 and a weak concave lens (0.25 D.) in front of the supposed 
 blind eye, and direct the patient to read the distant test 
 types; if he succeeds, it is proof of malingering, since it is 
 impossible for him to see with the sound eye when covered by 
 the strong lens. 
 
 4. Snellen's test types of alternate red and green color are 
 often used to detect malingering: We place a red glass before 
 the admittedly sound eye; if the subject reads the green 
 letters, he must do so with the so-called blind eye, since only 
 the red letters can be seen through the red glass. 
 
 It is uncommon for a patient to simulate blindness in hoih 
 eyes, and more difficult to detect him in such cases. A dimi- 
 nution in acuteness of vision of both eyes is more frequently 
 feigned than binocular blindness. In such cases, malinger- 
 ing is suspected, when there are absence of agreement in the 
 results of the functional and objective examination of the 
 eyes, contradictory statements regarding the different steps in 
 the functional examination, or contraction of the pupils to 
 light. In some instances, the pupils react on exposure to 
 light in cases of absolute blindness, the lesion being situated 
 in the visual centres or in the connection between these 
 centres and the corpora quadrigemina (3, Fig. 249). In 
 feigned binocular blindness a close watch must be kept on the 
 patient when he thinks he is free from observation, and the 
 following test may be employed: Place a lighted candle in 
 front of the patient; hold a 6° prism base outward before one 
 eye; if both eyes see, the one covered by the prism will move 
 
286 DISTURBANCES OF VISION 
 
 inward in order to avoid diplopia; on removing the prism it 
 will move outward, the other eye remaining fixed. 
 
 AMBLYOPIA AND AMAUROSIS FROM VARIOUS 
 CAUSES 
 
 Besides the forms of amblyopia already described, there 
 are others, of less frequent occurrence, due to ursemia, reflex 
 irritation, malaria, quinine, and wood-alcohol. A consider- 
 able number of drugs and poisons, also tea and coffee, are 
 occasionally responsible for more or less amblyopia. 
 
 Uraemic Amblyopia has been described on p. 258. 
 
 Reflex Amblyopia, due to reflex irritation, is rare and of 
 rather doubtful occurrence, except in the case of the teeth, 
 irritation from which has been found responsible for ambly- 
 opia in occasional instances. 
 
 Malarial Amblyopia has been observed, without apparent 
 changes in the fundus, as a result of the action of the malarial 
 poison upon the optic nerve. It affects one or both eyes, 
 lasts some hours or days, and usually disappears completely 
 as a result of the use of antiperiodics. 
 
 Quinine Amblyopia or Amaurosis occurs after large quan- 
 tities of quinine have been taken, occasionally with moderate 
 doses in susceptible individuals. Besides other symptoms of 
 cinchonism there are more or less complete blindness, often 
 noticed suddenly, contracted fields, dilated pupils, and'marked 
 pallor of the disc, with extreme contraction of the retinal ves- 
 sels. The condition is due to spasm of the retinal vessels 
 causing anaemia of the fundus, degeneration of the ganglion 
 cells and nerve fibres of the retina, and -later atrophy of the 
 optic nerve. After a time, central vision is restored com- 
 pletely or partially, and the field widens, but rarely regains its 
 full extent. Treatment consists in discontinuing the drug, 
 inhalations of amyl nitrite, the use of nitroglycerin, strych- 
 nine, digitalis, and the bromides. 
 
 Methyl-Alcohol Amblyopia or Amaurosis results from the 
 drinking of variable quantities of wood-alcohol in the form 
 of cheap whiskeys, cordials, essences, and other alcoholic 
 beverages, which are often adulterated with Columbian 
 
METHYL-ALCOHOL AMBLYOPIA 287 
 
 spirits, the trade name for rectified methyl-alcohol; it has 
 also been caused by inhaling the fumes to which the var- 
 nishers of the interior of beer casks, for instance, are exposed. 
 The general symptoms consist of severe gastro-intestinal dis- 
 turbance, headache, vertigo and sometimes coma, and not 
 infrequently terminate fatally. The ocular symptoms are 
 marked reduction of vision, peripheral contraction of the field, 
 and absolute central scotoma; blindness often follows. The 
 ophthalmoscopic appearances are hyperaemia of disc with 
 blurring of edges and, later, atrophy of the optic nerve with 
 small retinal vessels. The prognosis is unfavorable both to 
 life and to sight; some cases recover, but very few with useful 
 vision. The anatomical changes are alterations- in the gan- 
 glion cells of the retina with extension to the optic nerve. 
 Treatment consists in the use of pilocarpine, nitroglycerin, 
 potassium iodide, and later strychnine. 
 
 Night Blindness ( Nyctalopia, sometimes incorrectly called 
 hemeralopia) is a condition in which the sight is good by day or 
 with good illumination, but deficient at night or with reduced 
 illumination It is a symptom of certain forms of secondary 
 atrophy of the optic nerve, especially retinitis pigmentosa. 
 
 A second form of diminished light sense occurs without 
 ophthalmoscopic changes and is due to anaesthesia of the 
 retina, probably from defective regeneration of the visual 
 purple; this variety depends upon diminished ocular nutrition 
 as a result of a debilitated state of the system, such as exists 
 in starvation, profound anaemia, scurvy, and the like; some- 
 times there is the history of exposure to bright light; xerosis 
 of the conjunctiva is often present at the same time. The 
 condition is observed chiefly in the tropics, among the in- 
 mates of prisons, workhouses, and asylums; it is endemic in 
 some countries, Russia for example, after the Lenten fasts; 
 it is found most frequently in adult males, especially in the 
 spring of the year. The prognosis is favorable, though there 
 is some tendency to recur, and the defect usually disappears 
 with improvement of the general health by good and suffi- 
 cient food, tonics (cod-liver oil, iron), and the use of dark 
 glasses. 
 
288 DISTURBANCES OF VISION 
 
 Day Blindness ( Hemeralopia, sometimes incorrectly called 
 nyctalopia) is the name given to a condition in which the 
 sight is better at dusk or in feeble illumination than in bright 
 light. This symptom is found in toxic amblyopia and with 
 central scotoma in general. In cases in which there are cen- 
 tral opacities of the lens or cornea, the patient sees better in 
 reduced illumination because the dilated pupil permits vision 
 through the peripheral clear portion of the cornea and lens. 
 
 HEMIANOPSIA 
 
 Connection between the Retinae, the Fibres of the Optic Nerves 
 and Tracts, and the Cerebral Cortex (Figs. 170 and 249; also Plate 
 XXII). — ^Familiarity with the course of the optic-nerve fibres from 
 the eye tp thfe cortex is of great practical value in the localization of 
 various lesions causing defects in the field of vision. 
 
 The optic nerves terminate at the chiasm, which lies in the optic groove 
 on the body of the sphenoid bone, in front of the infundibulum and 
 above the hypophysis; here they semi-decussate; from the chiasm they 
 are continued backward as the optic tracts which wind around the crura 
 cerebri to the primary optic ganglia — the external geniculate body, 
 the anterior corpus quadrigeminum, and the pulvinar of the thalamus 
 opticus (POG, Figs. 170 and 249). Here the fibres divide into two 
 portions: (1) a smaller part passing to the nuclei of the oculomotorius 
 and presiding over the reflex action of the pupils and the movement 
 of the ocular muscles, and (2) a larger bundle, composed of visual fibres, 
 transfers its impulses (Fig. 170) to other fibres which carry the visual 
 impressions to the cortex; the latter fibres pass through the posterior 
 portion of the internal capsule, then form the optic radiations or fibres 
 of Gratiolet, and end in the cortical ganglion cells of the mesial surface 
 of the cuneus and the parts surrounding the calcarine fissure; this portion 
 of the occipital lobe is known as the visual area of the cortex (0, Fig. 249) . 
 
 In the ganglion cells of the visual area, an excitation in the optic- 
 nerve fibres is changed into a sensory perception (sight) or into perma- 
 nent changes (memories, optical-menbiory pictures). After destruction 
 of this area, excitation of the optic-nerve fibres either fails to arouse 
 visual sensation of any kind {blindness) or fails to summon forth any 
 recollection of objects or circumstances acquired through previous 
 education; in the latter case, objects are seen but not recognized 
 {psychical blindness). 
 
 Each retina is supplied by optic-nerve fibres passing to both sides 
 of the brain. Each optic nerve is composed of an external set of fibres 
 derived from the outer or temporal half of the retina, and an internal set 
 derived from the inner or nasal half of the retina. In the axis of the 
 optic nerve is found a special set of fibres which pass to the macula and 
 
HEMIANOPSIA 
 
 289 
 
 the space between it and the disc. These macular fibres, when they 
 reach the eyeball, are collected into a sector corresponding to the outer 
 third of the disc, the apex directed toward the centre and the base 
 toward the margin of the papilla. The external or temporal fibres are 
 continued along the lateral part of 
 the chiasm and tract and pass, to the 
 primary optic centre of the same 
 side. The inner fibres, derived from 
 the nasal half of the retina, pass 
 into the chiasm and decussate; they 
 are continued in the tract of the op- 
 posite side, thus passing to the side 
 of the brain opposite to the eye 
 which they supply. 
 
 The chiasm presents laterally the 
 direct or temporal fibres of both 
 eyes, and in its centre, the decus- 
 sation of the inner or nasal fibres of 
 both retinae. Consequently, the 
 decussation in the chiasm is not 
 complete but partial — a semi-de- 
 cussation. 
 
 Each optic tract contains fibres 
 from both eyes. The right optic 
 tract consists of non-decussating 
 fibres from the right (temporal) half 
 of the retina of the right eye, and 
 decussating fibres from the right 
 (nasal) haK of the left eye. Hence 
 the right halves of both relince and 
 thus the left halves of both visual 
 fields are connected with the right 
 tract (Plate XXII). It follows, 
 therefore, that the visual impulse 
 excited by pbjects placed to the left 
 of the median line passes to the 
 cortex of the right hemisphere by 
 means of the right optic tract; and 
 that the perception of all objects 
 placed to the right of the median 
 line is conveyed by the left optic tract to the cortex of the left 
 hemisphere. 
 
 Hemianopsia. — This arrangement of fibres in the chiasm 
 explains the occurrence of a form of visual disturbance known 
 
 Fig. 249. — Schematic Representation o£ 
 the Visual Paths. L, left eye; fi, right 
 eye; TL, temporal field of left eye; 
 NL, nasal field of left eye; NR, nasal 
 field of right eye; TR, temporal field of 
 right eye; ON, optic nerve; C, chiasm; 
 FOG, primary optic ganglia; OMN, 
 oculomotor nuclei; O, occipital lobe; 
 OR, optic radiations. Division of fibres 
 at 1 causes complete blindness of the 
 left eye and loss of direct pupillary re- 
 action; at 2, right homonymous hemi- 
 anopsia with loss of reaction of the pu- 
 pil when the left halves of the retlnEe 
 are illuminated; at 3, right homony- 
 mous hemianopsia with preservation of 
 the reaction of the pupil when the left 
 (and right) halves of the retinae are 
 illuminated, at 4, bitemporal hemi- 
 anopsia; at 5, left nasal hemianopsia. 
 
290 
 
 DISTURBANCES OF VISION 
 
 as hemianopsia (hemianopia, hemiopia), by which we mean the 
 loss of vision for corresponding halves or sectors of the visual 
 fields. If a lesion' interrupts the continuity of the right optic 
 tract, the right cortical visual area, or any portion of the 
 visual path between these parts, there will be blindness of the 
 right halves of both retinae; as a result, the left halves of the 
 fields of vision of both eyes will be lost, and only objects 
 which are placed to the right of the median line will be per- 
 ceived. This is known as homonymous or lateral hemianop- 
 sia, and in 
 this particular 
 case the con- 
 dition is called 
 left homony- 
 mous hemi- 
 opia, because 
 the left halves 
 of the fields 
 of vision are 
 wanting. Ho- 
 monymous 
 hemianopsia (Fig. 251), therefore, always points to a lesion 
 situated in the visual path or cortex on the central side of the 
 chiasm and upon the same side as the blind halves of the 
 retinae. It is the commonest form of hemianopsia. 
 
 If a lesion extends antero-posteriorly through the chiasm it 
 will destroy all the decussating fibres which supply the inner 
 or nasal halves of both retinae, and there will be a loss of 
 vision in the outer or temporal halves of the field of both 
 eyes, a condition called bitemporal hemianopsia (4, Fig. 249). 
 It is often seen in pituitary body disease. 
 
 If a lesion attacks each side of the chiasm, it will destroy 
 the non-decussating fibres which come from the temporal 
 halves of the retinae, and will, therefore, cause a loss of the 
 nasal or inner half of the field of vision of each eye; this is 
 known as binasal hemianopsia. Bitemporal and binasal 
 hemianopsia are known as crossed hemianopsia. It is doubt- 
 ful whether binasal hemianopsia ever occurs; another rare 
 
 Fig. 251. — The Fields of Vision in Right Homonymous 
 Hemianopsia. 
 
Fig. 250. — Schematic Representation of tlie Visual and the Pupillary Paths. 
 
HEMIANOPSIA 291 
 
 lorm of hemianopsia is altitudinal (inferior or superior) — 
 when the upper or the lower half of each field is wanting. 
 
 Hemianopsia is said to be complete when there is a sym- 
 metrical absence of the entire half of the field of vision. It is 
 tncomplete when there is an absence of a small portion or sec- 
 tor occupying a symmetrical position in the visual fields of the 
 two eyes; the lesion then involves only a portion of the fibres 
 of a visual tract or cortical visual area. 
 
 Even in cases of complete hemianopsia, the line between 
 the absent and the preserved portion of the field seldom 
 extends through the fixation point, the portion of the field 
 corresponding to the macula being usually preserved. In the 
 rare instances in which both halves of the fields are lost suc- 
 cessively (double homonymous hemianopsia), there will be 
 blindness except at the situation of these macular fibres, 
 indicating that the macula is supphed by a special region in 
 the cortical visual area. 
 
 Hemianopsia is known as absolute when there is loss of all 
 three functions of sight (light, form, and color sense); and 
 relative when only the color sense or both the color sense 
 and form sense are destroyed over the symmetrically defec- 
 tive areas, the light sense and the form sense being preserved 
 in the first instance, and the light sense only being present 
 in the second case. When the hemianopic defect is present 
 for colors alone, the condition is known as hemiachromatopsia; 
 it is believed to point to a lesion of less intensity than that 
 which causes absolute hemianopsia. 
 
 Complete blindness in one eye only is always due to a lesion 
 situated in jront of the chiasm. The same applies to scoto- 
 mata which are defects in the visual field of one eye (p. 17), 
 or non-S3Tnmetrical defects in the fields of both eyes; when 
 central, they indicate an involvement of the papillo-macular 
 sector of the optic nerve. 
 
 The Hemiopic Pupillary Reaction (Wernicke) is of value in 
 determining whether a lesion causing homonymous hemian- 
 opsia is situated behind or in front of the primary optic ganglia. 
 Light is thrown into the eye obliquely so as to illuminate one 
 or the other side of the retina. If the lesion is back of the 
 
292 DISTURBANCES OP VISION 
 
 ganglia, the pupillary light reflex will be preserved whether 
 the blind or the seeing half of the retina be lighted up; if in 
 front of these ganglia (in the optic tract) the pupil will 
 respond when light falls upon the seeing half of the retina, 
 but there will be no contraction or only a feeble reaction 
 when the blind half of the retina is illuminated (Fig. 170). 
 This test is a difficult one. 
 
 Scintillating Scotoma {Transient Hemianopsia) is a form of 
 temporary blindness generally associated with migraine and 
 probably due to a circulatory disturbance in the occipital 
 lobe. The attack begins with a central dark spot before both 
 eyes, which spreads by scintillating and colored zigzag lines 
 until there is a considerable gap in the field, often assuming 
 the form of homonymous hemianopsia. Accompanying the 
 attack there are headache, general malaise, vertigo, and some- 
 times nausea and vomiting. The attacks vary in frequency 
 and last about fifteen minutes, after which the amblyopia 
 disappears entirely. The affection occurs after excessive 
 mental or physical exertion and following marked eye strain. 
 Unless associated with paralysis, aphasia, or other symptoms 
 of cerebral trouble, it is not of serious import. Treatment 
 consists in attention to the general health, correction of eye 
 strain, avoidance of fatigue of any kind, and the use of 
 remedies suited to migraiae. 
 
CHAPTER XXI 
 
 GENERAL OPTICAL PRINCIPLES 
 
 From a luminous point, rays of light pass out in straight lines in 
 every plane and in every direction; the lines of direction are called rays. 
 These travel with a rapidity which diminishes with the density of the 
 medium traversed. The amount of divergence of the rays of Ught fall- 
 ing on a given area is inversely proportionate to the distance of the 
 luminous source; the nearer this point, the more divergence. When 
 proceeding from a point distant 20 feet or more, the divergence of rays 
 is so sUght that for practical purposes we assume them to be "parallel. 
 
 When a ray of light meets an opaque body, it is either absorbed or re- 
 flected. When it meets a transparent medium, some of it is absorbed 
 and reflected, but the greater part traverses the medium, being deflected 
 in its course; this bending is called refraction. 
 
 Reflection occurs from any pohshed surface (mirror) — plane, con- 
 cave, or convex. The ray striking the mirror is called the incident ray 
 (IB, Fig. 252); that returning 
 from the mirror, the reflected 
 ray {BR, Fig. 252). 
 
 Laws of Reflection: (1) The 
 angle of reflection is equal to 
 the angle of incidence. (2) The 
 reflected and incident rays are 
 both in a plane perpendicular 
 to the reflecting surface. In 
 Fig. 252 IB is the incident ray y^^ 252.-Reflection by a Plane Surface, 
 
 on the reflecting surface AC, 
 
 BR the reflected ray, and PB the perpendicular. The angle of inci- 
 dence, IBP, is equal to the angle of reflection, PBR. IB, PB, and 
 BR he in the same plane. 
 
 Reflection by a Plane Mirror. — The image is formed at a distance 
 behind the mirror equal to the distance of the object in front of it; it is 
 a virtual image, erect, and of the same size as the object. In Fig. 253, 
 O is the object, / the image, and E the eye of the observer. The image 
 of the candle is found behind the plane mirror MM; the observer's 
 eye E receives the rays from as if they came from I. 
 
 Reflection from a Concave Mirror. — A concave surface may be con- 
 sidered as made up of a number of plane surfaces incUned toward one 
 another. Parallel rays falling on a concave mirror are reflected as con- 
 vergent rays which meet on the axis of the surface at a point called 
 
 293 
 
294 
 
 GENERAL OPTICAL PRINCIPLES 
 
 Fig. 253. — ^Formation of 
 Image by a Plane 
 Mirror. 
 
 the principal focus {Pf, Fig. 254) ; the latter is midway between the 
 mirror and its optical centre C. The distance of the principal focus 
 fromthemirror is called the /ocaJ length of the 
 mirror. 
 
 The Position of an Image formed by a con- 
 cave mirror varies with the distance of the 
 object from the mirror. If the object be 
 placed at the principal focus, Pf, the reflected 
 rays are parallel to each other and to the axis of 
 the mirror. If the object be placed at the 
 centre of concavity C, the reflected rays return 
 along the same lines. If the object is beyond 
 the centre, at CF, the reflected rays focus be- 
 tween the centre and the principal focus at 
 cf; and conversely, if the object be moved be- 
 tween the principal focus and the centre, at cf, 
 its focus will be beyond the centre, at CF; 
 these two points, CF and cf, bear a reciprocal 
 relation to each other and are known as con- 
 jugate foci; the nearer the object approaches the principal focus 
 the greater the distance at which the reflected rays meet. If the object 
 be placed nearer the mirror than the principal focus, at X, reflected rays 
 win be divergent and never meet; if, however, these divergent rays are 
 continued backward, they 
 will unite at a point, Vf, 
 behind the mirror; this 
 point is called the virtual 
 focus, and an observer 
 placed in the path of the 
 reflected rays will receive 
 them as though they 
 came from this point. 
 
 It follows, therefore, 
 that concave mirrors pro- 
 duce an enlarged, erect, 
 and virtual image if the 
 object is placed nearer 
 than the principal focus; 
 no image of an object placed at the principal focus; an enlarged, in- 
 verted, real image if the object is placed between the principal focus 
 and the centre; an inverted image of the same size when placed at the 
 centre; and a smaller, inverted, real image if the object is placed 
 beyond the centre. 
 
 Reflection by a Convex Mirror. — Parallel rays falling on a con- 
 vex surface are reflected divergent and hence never meet; but if pro- 
 longed backward a negative image is formed at a . point called the 
 
 Fig. 254. — Reflection by a Concave Mirror. 
 
REFRACTION 
 
 295 
 
 Fig. 255.- 
 
 ■Reflection by, a Convex 
 
 Mirror. 
 
 •principal focus (Fig. 255, F). The image is always virtual, erect, and 
 smaller than the object, independent of the position of the object be- 
 fore the mirror. 
 
 Refraction is the deviation in the course of rays of hght in passing 
 from one transparent (dioptric) medium into another of different density 
 (refracting medium). The ray which falls 
 perpendicular to the surface separating 
 the two media is not refracted but con- 
 tinues in a straight course (Fig. 256,PP). 
 
 In passing from a rarer to a denser 
 medium, a ray is refracted toward the 
 perpendicular to the refracting surface; 
 in passing from a denser to a rarer 
 medium, the ray is refracted away 
 from the perpendicular. In Fig. 257, 
 
 the incident ray IR, in passing from a rarer medium (air) into a 
 denser medium (glass), is refracted toward the perpendicular PP; 
 in passing from a denser to a rarer medium, the emergent ray EB is 
 
 refracted from the perpendicular 
 
 DH^^^^^^^^^HH PP. The ray continues in a line 
 IB|^^^^^^^^^H parallel to its original course, but 
 ^I^S^^^^^^^I has suffered lateral deviation. The 
 ^^^if^^^^^^ angle formed by the incident ray 
 m i\\ M with the perpendicular, IRP, is 
 
 ^^^■HaBIHHHH known as the angle of incidence; 
 ^^^Kl^S^S^^M ^^^ angle formed by the emergent 
 ^^^H^^HK^B or refracted ray with the perpen- 
 ^^^^^^^^^■Hi dicular, PER, is known as the 
 angle of refraction. 
 
 Index of Refraction. — The rela- 
 tive density, or the comparative 
 length of time occupied by light 
 in travelling a definite distance in 
 different transparent media, is known as the index of refraction. Air 
 being taken as 1.00, the index of refraction of water is 1.33, of the 
 cornea 1.33, of the lens 1.40, of crown glass 1.5, of flint glass 1.6, 
 and of diamond 2.50. 
 
 PRISMS 
 
 A prism is a piece of glass or other refracting substance 
 bounded by plane surfaces inclined toward each other (Fig. 
 258). The angle formed by the two surfaces is called the 
 refracting angle of the prism (BAC), the thin edge where the 
 intersecting surfaces meet is known as the apex {A), and the 
 opposite thick portion as the base (BC). 
 
 Fig. 256. Fig. 257. . 
 
 Fig. 256. — Passage of a Perpendicular 
 
 Ray Through a Transparent Medium. 
 Fig. 257. — Refraction by a Transparent 
 Medium with Parallel Surfaces. 
 
296 GENERAL OPTICAL PRINCIPLES 
 
 Refraction by a Prism. — Rays of light passing through a 
 prism are benl toward the base. In Fig. 258, the incident ray 
 
 Fig. 258. — Refraction by a Prism. FiG. 259. — Passage of Parallel Rays 
 
 Through a Prism 
 
 IR is refracted toward the perpendicular PR, at R, and 
 assumes the direction RR in the prism; on emerging, it is 
 refracted away from the perpendicular and continues as RE 
 toward the base of the prism. To the eye placed at E, the 
 ray RE seems to come from X; hence an object seen through 
 a prism appears displaced toward the apex. A prism has 
 neither converging nor diverging power, and therefore has no 
 focus and cannot form an image; rays that are parallel 
 before entering the prism are parallel on emerging (Fig. 259). 
 
 The Numbering of Prisms. — The strength of a prism is 
 expressed (1) in degrees, (2) in centrads, and (3) in prism- 
 diopters. In the first method (degrees), which in spite of 
 certain faults is the one most generally used, the value of the 
 prism corresponds to the refradin^angle (geometrical angle) 
 and is expressed: Prism 1°, 2°, 10°, etc. A centrad corre- 
 sponds to a deviation, the arc of which is ^ of the radius, 
 and is expressed Iv, 2v, lOV, etc. The prism diopter is a 
 deviation, the tangent of which is ^ of the radius, and is 
 expressed: 1 P. D. or 1 A, 2 P. D. or 2A, etc. Within the 
 limits of common use, the three scales can practically be 
 considered alike. 
 
 The Position of a Prism when placed in front of an eye is 
 indicated by the direction of its base; " base out " means that 
 the thick part of the prism is toward the temple; the base 
 may be up, down, in, or out. 
 
 The Uses of Prisms: (1) To counteract the effects of mus- 
 cular paralysis or insufficiency; (2) for the exercise of weak 
 muscles; (3) to test the extent to which the eyes can be de- 
 
SPHERICAL LENSES 
 
 297 
 
 viated from parallelism; (4) as a test for heterophoria; (5) 
 for detecting simulated blindness. 
 
 LBirSES 
 
 A lens is a transparent refracting medium, usually made of 
 glass, in which one or both surfaces are curved. There are 
 two kinds: spherical and cylin- 
 drical lenses. 
 
 Spherical Lenses are so called 
 because the curved surfaces are 
 segments of spheres (Fig. 260); 
 such lenses refraci rays of light 
 equally in all meridians or planes. 
 There are two kinds of spherical 
 lenses, convex and concave. 
 
 Convex Spherical Lenses are 
 formed of prisms with their bases 
 together and toward the centre 
 (Fig. 261, A); theyare therefore 
 thick at the centre and thin at the 
 edge. They are known as converging, magnifying, positive, 
 and plus lenses, and denoted by the sign +. They have 
 the power of converging parallel rays and of bringing them 
 to a, jocus (Fig. 264). There are three different forms: (1) 
 
 Fio. 260.— The Relation of the Sur- 
 faces of Lenses to Spheres. 1. 
 Plano-convex; 2, biconvex; 3, con- 
 vex meniscus; 4, plano-concave; 
 5, biconcave; 6, concave menis- 
 cus. 
 
 Fig. 261. — ^The For- FiG. 262.-M^onvex Lenses. FiG.263. — Concave Lenses, 
 
 mation of Lenses by 1. Plano-convex; 2, bi- 1. Plano-concave; 2, bi- 
 
 Prisms. convex; 3, convex men- concave: 3, concave 
 
 iscus. meniscus. 
 
 Plano-convex, one surface plane, the other convex (1, Fig. 
 262) ; (2) biconvex or double convex, both surfaces convex 
 (2, Fig. 262); (3) concavo-convex {convex periscopic, convex 
 or converging meniscus), one surface convex, the other 
 
298 
 
 GENERAL OPTICAL PRINCIPLES 
 
 concave — the former having the shorter radius of curva- 
 ture (3, Fig. 262). The periscopic lens (whether + or — ) 
 diminishes spherical aberration and enlarges the field of 
 vision. 
 
 Concave Spherical Lenses are formed of prisms with their 
 apices together and toward the centre (Fig. 261, B); they are 
 therefore thin at the centre and thick at the edge. They are 
 known as diverging, reducing, negative, or minus lenses, and 
 
 Fig. 264. — ^The Action of a Convex 
 Lens on Parallel Rays. 
 
 Fig. 265. — The Action of a Concave 
 Lens on Parallel Rays. 
 
 denoted by the sign — . Rays of light after passing through 
 a concave lens are rendered divergent; if prolonged backward 
 they form an image on the same side as the object (Fig. 265). 
 There are three different forms: (1) Plano-concave, one sur- 
 face plane, the other concave (1, Fig. 263) ; (2) biconcave or 
 double concave, both surfaces concave (2, Fig. 263) ; (3) con- 
 vexo-concave {concave periscopic, concave or diverging menis- 
 cus), one surface convex and the other concave, the latter 
 having the shorter radius of curvature (3, Fig. 263). 
 
 The Action of Spherical Lenses.^ — Since spherical lenses are 
 formed of prisms with their bases (convex) or apices (con- 
 cave) in apposition, and since rays in 
 passing through a prism are refracted 
 toward its base, it follows that convex 
 lenses cause convergence (Fig. 264), and 
 concave lenses produce divergence of rays 
 (Fig. 265). 
 
 A line passing .through the centre of 
 the lens (optical centre or nodal point, 
 0, Fig. 266) at right angles to the surfaces of the lens 
 is called the principal axis (AB, Fig. 266). A ray passing 
 through this axis (axial ray) is not refracted; all other rays 
 
 Fig. 266. — Principal and 
 Secondary Axes of a 
 Convex Lens. 
 
FOCI OF CONVEX LENSES 299 
 
 suffer more or less refraction. Rays passing through the 
 optical centre of a lens, but not through the principal axis 
 {secondary rays) are slightly deviated, but emerge in the same 
 direction as they entered {CD and EF, Fig. 266) ; the devia- 
 tion in thin lenses is so slight that practically they may be 
 considered as straight lines and are called secondary axes. 
 
 Foci of a Convex Lens. — ^The point to which rays converge 
 after refraction by a convex lens is called its focus. The 
 principal focus is the focus 
 for parallel rays (F, Fig. 
 267); the distance of this 
 point from the optical cen- 
 tre is called the focal dis- 
 tance of the lens (XF, Fig. 
 267). Since the course of 
 
 a ray passing from ' one Fig. 267. — ^The Principal Focua of a Convex 
 
 point to another is the °^' 
 
 same, independent of the direction, it follows that rays from 
 a luminous point placed at the principal focus will emerge 
 as parallel after passing through the lens. 
 
 In Fig. 267, the rays ABC strike the surface of the lens at LMN; 
 the axial ray B strikes the lens at M perpendicular to its surface and 
 consequently continues in a straight Une to F. The ray A strikes the 
 lens obliquely at L and is bent toward the perpendicular of the surface 
 of the lens at that point, shown by the dotted line PR; on leaving the 
 lens obliquely at S it is deflected away from the perpendicular RT, 
 being directed to F where it meets the axial ray BF. The ray C is re- 
 fracted in a similar manner; it is bent upon entering the lens at N and 
 rendered additionally convergent when emerging from the lens, and 
 finally it meets the other rays at F. If, in this same illustration, the 
 rays proceed from F, the principal focus, they emerge parallel {LA, 
 MB, NC) after passing through the lens. 
 
 Conjugate Foci of a Convex Lens. — Conjugate foci are interchange- 
 able foci in which the image can be replaced by the object and the object 
 by the image. When divergent rays (i.e., rays coming from a point 
 nearer than twenty feet) proceed from a point beyond the principal 
 focus, they will meet at a point beyond the principal focus on the other 
 side of the lens. The more distant the luminous point, the nearer the 
 principal focus (on the other side of the lens) will the rays be focussed. 
 If the luminous point is situated at a distance equal to twice the focal 
 length of the lens, the rays will f ocue at the same distance on the opposite 
 side. These are conjugate foci. ^ 
 
300 
 
 GENERAL OPTICAL PRINCIPLES 
 
 Pig. 296. — Conjugate Foci of a Convex Lens. 
 
 In Fig. 268, the rays diverging from and passing through the lens 
 converge at /; if they diverge from I, they would return in the same 
 path, and meet at 0; the points O and I are conjugate foci. In the 
 
 preceding ex- 
 ample the con- 
 jugate focus is 
 positive or real. 
 Virtual or 
 Negative Focus 
 of a Convex 
 Lens. — When 
 rays diverge 
 from some point between the lens and its principal focus (Pig. 269, 0), 
 they wiU continue divergent after refraction, but less so than before 
 entering the lens; if prolonged backward they will meet at a point (7, 
 Fig. 269) on the same side of the lens from which they diverged; this 
 point is a negative or virtital focus. 
 
 Foci of a Concave Lens. — After passing through a concave lens, rays 
 of light, whether originally parallel or divergent, are always divergent 
 and the focus is, therefore, 
 always negative or virtual; it 
 is found by continuing these 
 divergent rays backward un- 
 til they meet at a point 
 (Fig. 265). 
 
 Formation of Images. — The 
 image of an object formed by 
 a lens is a collection of foci, each corresponding to a point in the ob- 
 ject. Such images are either real or virtual. A real image is formed by 
 the meeting of rays; it can be projected on a screen. A virtual image is 
 formed by the prolongation backward of diverging rays imtil they meet at 
 
 a point; it can 
 only be seen by 
 looking through 
 the lens. 
 
 To find the 
 Position and 
 Size of an Im- 
 age formed by a 
 lens, it is neces- 
 sary to obtain 
 the conjugate 
 focus of each extremity of the object: Two lines are drawn from each 
 of these points, one parallel to the axis of the lens and then through 
 the principal focus, and the other through the optical centre; the im- 
 
 FiG. 269.— Virtual Focus of a Convex Lens. 
 
 Fig. 270.- 
 
 -Real, Inverted, and Reduced Image Formed by a 
 Convex Lens. 
 
FORMATION OF IMAGES BY LENSES 
 
 301 
 
 age will be formed at the point where these rays intersect (Figs. 270, 
 271, 272). 
 
 In Fig. 270, AB is the object, is the optical centre of the lens, and 
 PF its principal focus. From A, two rays are drawn, one parallel to 
 the axis of the lens 
 and then through the 
 principal focus PF, 
 and a secondary ray 
 through O; the im- 
 age of the point A 
 is formed at a, where 
 these two lines inter- 
 sect. The conjugate 
 focus of B is found 
 in the same manner. 
 
 The Relation in Size between Image and Object depends upon their 
 respective distances from the optical centre of the lens. In Fig. 270, 
 the object is placed at a greater distance than twice the principal focus, 
 hence the image is real, inverted, and smaller. If the object is situated 
 
 Fig. 271. — Real, Inverted, and Enlarged Image Formed by 
 a Convex Lens. 
 
 Fig. 272. — Virtual Image Formed by a Convex 
 Lens. 
 
 Fig. 273. — Virtual Image Formed 
 by a Concave Lens. 
 
 at exactly twice the distance of the principal focus, the image will be 
 real, of the same size, and inverted. If the object is situated just be- 
 yond the principal focus, the image will be real, enlarged, and inverted 
 (Fig. 271). If the object be placed at the principal focus, the rays will 
 be parallel after refraction and no image wiU be obtained. If the object 
 be nearer than the principal focus, the rays wiU be divergent after pass- 
 ing through the lens (Fig. 272), and no real image will be formed; but by 
 projecting these rays backward they would meet, and an eye placed at 
 PF, Fig. 272, win receive the rays from AB as if they came from o6; 
 the image will be enlarged, erect, and virtual; it is on the same side of the 
 lens as the object, and is seen only by looking through the lens, which 
 acts as a magnifying glass. 
 
 Images formed by Concave Lenses are always virtual, erect, and 
 smaller than the object; they are seen only by looking through the lens, 
 which acts as a reducing glass (Fig. 273). 
 
 Cylindrical Lenses. — A cylindrical lens or cylinder is a seg- 
 
302 
 
 GENERAL OPTICAL PRINCIPLES 
 
 ment of a cylinder parallel to its axis (Fig. 274). Cylinders 
 are divided into convex and concave. Light passing through a 
 cylinder in the plane of its axis is not refracted and behaves 
 exactly as though passing through a plate of glass with parallel 
 sides; in this direction, the surface of the lens is straight. 
 But when light passes through in a plane opposite or perpen- 
 dicular to the axis of a cylinder, the rays are rendered conver- 
 gent or divergent, according as the cylinder is convex or con- 
 cave; in this direction the surface of the lens is curved. 
 Parallel rays of light after refraction by a cylinder §,re fo- 
 
 FiG. 274. — The Construc- 
 tion of a Convex and 
 a Concave Cylindrical 
 Lens from a Cylinder. 
 
 Fig. 275. — ^The Action of 
 a Convex Cylindrical 
 Lens upon Parallel 
 Rays. 
 
 Fig. 276. — The Action cf 
 a Concave CylindricU 
 Lens upon Parallel 
 Rays. 
 
 cussed in a straight line which corresponds to the axis of the 
 cylinder (Figs. 275, 276). A spherical lens refracts equally 
 in all planes; a cylindrical lens does not refract in the axial 
 plane, but all other rays are refracted, those the most which 
 pass at right angles to its axis. It is necessary to indicate 
 the direction of the axis of a cylinder; in the lenses of the trial 
 case, used for the estimation of the refraction of the eye, 
 this is done by a short linear scratch on the lens at its margins 
 or by having a portion of the surface on each side ground 
 parallel to its axis (Fig. 278). 
 
 I The Numeration of Lenses. — The strength of a lens refers to 
 its power of bringing parallel rays to a focus — i.e., its refrao- 
 
THE NUMERATION OF LENSES 
 
 303 
 
 live power; this is indicated by its principal Jocal distance, the 
 interval between the optical centre of the lens and the prin- 
 cipal focus. The shorter this distance, the stronger the lens; 
 the greater the principal focal distance, the weaker the lens. 
 The strength of a lens is the inverse of its focal distance. 
 
 There are two systems of numbering lenses: (1) The Inch, 
 and (2) the Metric or Dioptric. 
 
 In the Inch System, the unit is a strong lens which brings 
 parallel rays to a focus at one inch; this is known as -f or 1, 
 and every other lens is a fraction of this unit, in which the 
 focal distance in inches forms the denominator. For instance, 
 i has a focal distance of 4 inches, yj of 10 inches, -j5 of 40 
 inches. Such lenses are also expressed by the terms No. 4, 
 No. 10, No. 40, indicating their focal strength. This sys- 
 tem, though very simple, is open to the objections (1) that 
 the inch varies in length in different countries, (2) the lack 
 of uniform intervals, and (3) the inconvenience of adding or 
 subtracting vulgar fractions in practical work. 
 
 The Metric or Dioptric System accepts as its unit a lens 
 which has its principal focus at one meter distance (39| Eng- 
 
 FiG. 277. — Spherical Lens from 
 Trial Case, 
 
 Fig. 278. — Cylindrical Lens from 
 Trial Case. 
 
 lish inches, in round numbers 40 inches); this lens is known 
 as 1.00 diopter (abbreviated D.). Every lens is mmabered by 
 its strength in whole numbers and in decimal fractions (0.25, 
 
304 
 
 GENERAL OPTICAL PRINCIPLES 
 
 0.50, 0.75). A lens which has twice the strength of the unit 
 is known as 2 D.; its focal distance is one-half of a meter. 
 If the lens has a strength four times that of the unit, it is 
 called 4 D., and its focal distance is one-quarter of a meter. 
 If ten times as strong as the unit, it is known as 10 D., and 
 its focal distance is one-tenth of a meter. If one-quarter, 
 one-half, or three-quarters as strong as the unit, it is known 
 as 0.25 D., 0.50 D., or 0.75 D. respectively. In this system 
 the nmnber of the lens does not express its focal distance; but 
 the focal distance in centimeters is obtained by dividing 100 
 cm. by the number of the lens; for example a 2 D. lens has a 
 
 tance of ^ = 20 cm. The dioptric system is the one now 
 universally adopted. 
 
 To convert the focal distance in inches into the focal distance 
 in diopters, or vice versa, divide the number 40 by the number 
 of inches or diopters expressed. For example, 8 D. = f =5 
 inches =^; 0.50 D. =5^=80 inches = ^; ^ (twenty inches) 
 =i = 2 D.; i (ten inches) = jj = 4 D. The following 
 table gives the commonly employed (approximate) equiva- 
 lents in the inch and the dioptric systems: 
 
 COMMONLY EMPLOYED (APPROXIMATE) EQUIVALENTS OP LENSES NUM- 
 BERED IN THE DIOPTRIC AND INCH SYSTEMS 
 
 Diopters 
 
 Inches 
 
 Diopters 
 
 Inches 
 
 Diopters 
 
 Inches 
 
 Diopters 
 
 Inches 
 
 0.25 
 
 160 
 
 2.25 
 
 18 
 
 5.60 
 
 7.0 
 
 13 
 
 3.0 
 
 0.50 
 
 80 
 
 2.60 
 
 16 
 
 6.00 
 
 6.5 
 
 14 
 
 2.8 
 
 0.75 
 
 50 
 
 2.75 
 
 14 
 
 7.00 
 
 5.25 
 
 15 
 
 2.6 
 
 1.00 
 
 40 
 
 3.00 
 
 13 
 
 8.00 
 
 6.0 
 
 16 
 
 2.4 
 
 1.25 
 
 32 
 
 3.50 
 
 11 
 
 9.00 
 
 4.5 
 
 , . 
 
 
 1.50 
 
 26 
 
 4.00 
 
 10 
 
 10.00 
 
 4.0 
 
 18 
 
 2.2 
 
 1.75 
 
 22 
 
 4.50 
 
 9 
 
 11.00 
 
 3.5 
 
 , , 
 
 > > ■ 
 
 2.00 
 
 20 
 
 5.00 
 
 8 
 
 12.00 
 
 3.3 
 
 20 
 
 2.0 
 
 The Trial Case (Fig. 279) is a box containing -|- and — 
 spherical, and -|- and — cylindrical lenses, arranged in pairs. 
 The spherical lenses usually correspond to those given in the 
 
THE TRIAL CASE OP LENSES 305 
 
 preceding table (30 pairs), the weaker ones separated by inter- 
 vals of 0.25 D. (sometimes 0.12 D.), those of moderate 
 strength by 0.50 D., and the stronger ones by 1 D. The 
 cylindrical lenses usually run from 0.25 D. to 6.00 D. The 
 + lenses are mounted in nickelled rims, the — lenses in brass 
 
 Fig. 279. — The Trial Case ol Lenses. 
 
 rims. Besides these lenses, a complete trial case contains a 
 set of prisms, various metal discs one of which (obturator) is 
 solid and is used to exclude one eye in the examination, and 
 a trial spectacle frame (Fig. 289). 
 
 Recognition of the Kind of Lens and Estimation of its 
 Strength. — By moving a spherical lens before the eye and 
 looking at an object, the latter will appear to move, rapidly 
 if the lens is a strong one, slowly if a weak one. If the 
 object seems to move in the opposite direction and appears 
 enlarged, the lens is convex. If the object appears to move in 
 the same direction and seems smaller, the lens is concave. 
 
 When a cylinder is moved before the eye in the direction of 
 its axis, an object looked at does not appear to change its posi- 
 tion; when moved in the opposite direction, objects appear to 
 move as with spherical lenses — in the opposite direction when 
 the cylinder is convex, in the same direction when concave. 
 
 Having recognized the character of the lens, the strength 
 can be determined by neutralizing. Lenses of opposite kind 
 and known strength are taken from the trial case and placed 
 in front of the one to be tested, and the two lenses moved in 
 front of the eye. The neutralizing lens is the one which stops 
 all apparent movement of an object looked at, when the com- 
 
306 GENERAL OPTICAL PRINCIPLES 
 
 bined lenses are moved in front of the eye. The Lens Meas- 
 ure (Fig. 280) furnishes a very quick and reliable method of 
 determining the character and strength of any lens. 
 
 Finding the Centre of the Lens. — Unless especially desired 
 (for prismatic effect) the optical -centre of the lens should 
 coincide with the geometric centre. To 
 find the optical centre we look at two 
 lines at right angles to each other through 
 the lens held a few inches above. The 
 portion of the vertical and of the horir 
 zontal line seen through the lens is made 
 continuous with the portion seen beyond 
 the lens; then the two lines should cross 
 Fig. 280.— Lens ^t the geometrical centre of the lens, 
 easure. Varieties of Lenses Used to Correct 
 
 Errors of Refraction: 1. Simple spherical lens, convex or 
 concave. 2. Simple cylindrical lens, convex or concave. 3. 
 Sphero-cylinder, a combination of a spherical with a cylin- 
 drical lens. 4. Cross-cylinder, a combination of two cylin- 
 drical lenses with their axes at right angles to each other 
 (infrequently used). 5. Simple prism. 6. Prism combined 
 with various lenses. 
 
 Abbreviations and Signs Used in Ophthalmology 
 
 A. or Ace Accommodation. 
 
 Am Ametropia. 
 
 As Astigmatism, astigmatic. 
 
 As. H Hyperopic astigmatism. 
 
 As. M Myopic astigmatism. 
 
 Ax Axis (of cylindrical lens). 
 
 B Base (of prism). 
 
 C. or Cyl Cylindrical lens or cylinder. 
 
 cm Centimeter. 
 
 D Diopter 
 
 E Emmetropia or emmetropic. 
 
 F Field of vision. 
 
 H Hyperopia, hyperopic, horizontal. 
 
 HI Hyperopia latent. 
 
 Hm Hyperopia manifest. 
 
 Ht Hyperopia total. 
 
 L. or L. E Left eye. 
 
ABBREVIATIONS AND SIGNS 307 
 
 M Myopia or myopic. 
 
 m Meter. 
 
 M. A Meter angle. 
 
 mm Millimeter. 
 
 n Nasal. 
 
 O. D. (R., or R. E) Oculus dexter (right eye). 
 
 O. S. (L., or L. E.) Oculus sinister (left eye). 
 
 O. U Oculus uterque (both eyes). 
 
 Oph Ophthalmoscope Or ophthalnioscopic. 
 
 P. D Prism diopter. 
 
 P. L Perception of light. 
 
 P. p Punctum proximum (near point). 
 
 P. r Punctum remotum (far point). 
 
 Pr Presbyopia. 
 
 R. or R. E Right eye. 
 
 S. or Sph Spherical lens. 
 
 t Temporal. 
 
 T Tension. 
 
 V Vision, visual acuteness, vertical. 
 
 w With 
 
 + Plus or convex. 
 
 — Minus or concave. 
 
 = Equal to. 
 
 O Combined with. 
 
 00 Infinity (20 feet or more distance). 
 
 ' Foot, minute. 
 
 " Inch, second. 
 
 '" Line. 
 
 ° Degree (prism). 
 
 y Centrad (prism). 
 
 A Prism diopter. 
 
CHAPTER XXII 
 
 OPTICAL CONSIDEEATION OF THE EYE 
 
 The eye may be considered as an optical instrument, often compared 
 to the photographic camera, in which by means of a refracting (dioptric) 
 system a small and inverted image of external objects is formed on the 
 retina; it is well adapted for its function of refraction; the outermost 
 portion of the retina consists of a layer of pigment cells which absorbs 
 the excess of light and prevents dazzUng. The impression received by 
 the rods and cones is conveyed through the optic nerve to the cortical 
 area where the visual act is completed and results in the sense of sight. 
 
 Dioptric Apparatus of the Eye. — In passing through the eyeball 
 rays of light traverse the cornea, aqueous, lens, and vitreous. The 
 refracting surfaces of the eye are the cornea, the anterior surface and the 
 posterior surface of the lens; the refracting media are the aqueous, the 
 substance ofc the lens, and the vitreous. These surfaces and media con- 
 stitute the dioptric or refractive apparatus of the eye, a system which is 
 represented by a convex lens of 23 mm. focus; hence in an emmetropic 
 eye, in a condition of rest, parallel rays are brought to a focus on the 
 retina. The greatest deflection of rays takes place at the anterior sur- 
 face of the cornea; additional deviations occur at the anterior and pos- 
 terior surfaces of the lens. In each case the effect is one of convergence. 
 By the term refraction of the eye, we mean the changes which the ocular 
 media exert upon rays of light when the eye is in a stale of rest. 
 
 Cardinal Points of the Eye. — It is necessary to know the cardinal 
 points of the eye (Fig. 281) in order to understand the course of rays of 
 light through this organ; they are the two principal points, the two 
 nodal points, and the two principal foci, aU situated on the optical axis. 
 
 The Principal Points (P, Fig. 281) are two points so related that when 
 an incident ray passes through the first principal point, the correspond- 
 ing emergent ray passes through the second principal point. These two 
 points are placed so close together in the anterior chamber that they may 
 be considered as one point, situated about 2 mm. behind the cornea. 
 
 The Nodal Points (N, Fig. 281) correspond practically to the optical 
 centre of the dioptric system; they are so close together that they may 
 be considered as one point situated near the posterior pole of the lens 
 about 7 mm. behind the cornea. Rays passing through this point are 
 not refracted and form either the axial or secondary rays. 
 
 The First Principal Focus {A, Fig. 281) is that point oil the axis 
 at which parallel rays in the vitreous meet; it is situated about 14 mm. 
 in front of the cornea. 
 
 308 
 
CARDINAL POINTS OF THE EYE 
 
 309 
 
 Fig. 281.- 
 
 -Cardinal Points of 
 the Eye. 
 
 The Second Principal Focus {F, Fig. 281) is that point on the axis 
 at which parallel rays meet after being refracted by the dioptric system 
 of the eye; it is situated to the inner side of the macula, between it and 
 the optic disc, about 23 mm. behind 
 the cornea. 
 
 The Centre of Rotation of the eye- 
 ball (iS, Fig. 281) is situated in the 
 vitreous, about 10 mm. in front of, 
 the retina. 
 
 The Optical, Axis {A F, Fig. 281) 
 is the line connecting the centre of 
 the cornea, the nodal point, and the 
 posterior principal focus. 
 
 The Visual Line (0 M, Fig. 281) 
 is the hne passing from the object 
 looked at, through the nodal point, 
 to the macula. 
 
 The Line of Fixation is the line 
 joining the object looked at with the 
 
 centre of rotation; practically it corresponds to the visual line. 
 
 The Angle Gamma (y. Fig. 281) is the angle formed by the optical 
 
 axis with the hne of fixation (practically with the visual hne) ; it varies 
 
 with the refraction of the eye, being about 
 
 5° in emmetropia, larger in hyperopia, and 
 
 smaller in myopia. 
 
 The Angle Alpha is the angle formed by the 
 visual hne with the major axis of the corneal 
 ellipse. 
 
 BEmACTION OF THE EYE 
 
 Emmetropia.- — When parallel rays 
 are focussed exactly on the retina with 
 the eye in a condition of rest, the re- 
 fraction of the ejre is normal or emme- 
 tropic (Fig. 282) and the condition is 
 known as emmetropia. 
 
 Ametropia. — When, with the eye 
 in a condition of rest, parallel rays 
 are not focussed on the retina, but be- 
 hind or in front of it, the eye is ametro- 
 pic, and the condition is known as 
 
 ametropia. The forms of ametropia (errors of refraction) are 
 
 hyperopia, myopia, and astigmatism. 
 
 Fig. 282. — Emmetropia. 
 Fig. 283. — Hyperopia. 
 Fig. 284. — Myopia. 
 
310 
 
 OPTICAL CONSIDERATION OF THE EYE 
 
 Hyperopia is that form of ametropia in which the axis of 
 the eyeball is too short or the refractive power of the eye 
 too weak, so that parallel rays, are brought to a focus behind 
 the retina (Fig. 283). 
 
 Myopia is that form of ametropia in which the axis of 
 the eyeball is too long or the refractive power too strong, so 
 that parallel rays &Tefocussed in front of the retina (Fig. 284). 
 
 Astigmatism is that form of ametropia in which the refrac- 
 tion of the several meridians of the eyeball is different (Figs. 
 310-314). 
 
 ACCOMMODATIOIT 
 
 Accommodation is the power of altering the focus of the eye 
 so that divergent rays (those coming from an object nearer 
 than 20 feet) are brought together on the retina; this is ac- 
 complished by means of an increase in. the convexity of the lens 
 and thus in its refractive power. The degree of accommoda- 
 
 FlG. 285. — The Emmetropic Eye in 
 a State of Rest. 
 
 Fig. 286. — The Emmetropic Eye 
 During Accommodation. 
 
 tion must vary for every distance of the object; the eye cannot 
 be adapted for two different distances at the same time. 
 
 In the emmetropic eye ai rest, parallel rays are brought to 
 a focus on the retina (P F, Fig. 285), but rays coming from a 
 near object {divergent rays) are focussed behind the retina 
 (D X, Fig. 285); hence distant objects appear distinct and 
 near objects blurred. If the refractive power of the eye is 
 increased by accommodation, parallel rays will be brought to 
 a focus in front of the retina (P F, Fig. 286), while divergent 
 rays will be focussed on the retina (D X, Fig. 286); conse- 
 quently near objects appear distinct and distant objects 
 appear blurred during accommodation. 
 
 Mechanism of Accommodation. — The lens is an elastic 
 structure, and when released from the flattening influence of 
 
ACCOMMODATION • 311 
 
 its suspensory ligament tends to assume a spherical shape. 
 During accommodation, the ciliary muscle (especially the 
 circular fibres) contracts, drawing forward the choroid and 
 relaxing the suspensory ligament; this diminishes the tension 
 of the lens capsule and allows the inherent elasticity of the 
 lens to increase its convexity. The change 
 in curvature affects chiefly the anterior sur- 
 face of the lens (Fig. 287). This is Helm- 
 holtz's theory and the one usually accepted. 
 Tscherning has advanced a different theory: 
 He maintains that the ciliary muscle in- 
 creases the tension of the suspensory liga- 
 ment during contraction, and that this 
 causes peripheral flattening of the lens with 
 bulging anteriorly at its centre. _ ^'^- aeTAnterior 
 
 The act of accommodation is accompa- Portion ot the 
 nied by contraction of the pupil and by con- fedti^esiuultrate 
 vergence of the visual lines. the changes dm- 
 
 The Far Point.— When the eye is in a •°8^^'='"»"™<"i»- 
 state of rest, with accommodation com- 
 pletely relaxed, it is adapted for its far point (punctum re- 
 motum). This is the farthest point of distinct vision, and 
 in the emmetropic eye it is situated at infinity. 
 
 The Near Point {punctum proximum) is the nearest point at 
 which the eye can see distinctly when employing its maximum 
 amount of accommodation. It varies with the amount of 
 accommodation possessed by the eye. The usual plan of 
 determining the near point is to note the shortest distance 
 at which the patient can read the smallest test type (Jaeger, 
 No. 1, Fig. 18) with each eye separately. 
 
 The Range of Accominodation is the distance between the 
 far point and the near point. 
 
 The Amplitude of Accommodation is the difference between 
 the refractive power of the eye when at rest and when the 
 accommodation is exerted to the utmost. It is expressed in 
 diopters representing that convex lens which it would be 
 necessary to place before the eye to take the place of accom- 
 modation for the near point. 
 
312 OPTICAL CONSIDERATION OF THE EYE 
 
 The amplitude of accommodation in diopters is found by 
 dividing 40 by the distance of the near point in inches, or 100 
 by the near point in centimeters; for example, if the near 
 point of an emmetropic eye is 8 inches or 20 cm., g or 20 = 5 
 D. = amplitude of accommodation; this rule applies to emme- 
 tropia. 
 
 In hyperopia some of the accommodation is required for 
 distant vision; hence we find the apparent amplitude of ac- 
 commodation and then add that lens which enables the 
 patient to see distant objects without his accommodation; 
 for example, if the near point of a hyperopic eye is 8 inches 
 or 20 cm., and the patient is compelled to use 2 D. of accom- 
 modation for distant objects, his amplitude of accommoda- 
 tion would be f (or ^)= 5+2 = 7 D. With the same am- 
 plitude of accommodation the near point is farther away than 
 in emmetropia, since some of the power of accommodation is 
 expended in adapting the eye for distant objects; and if the 
 near point were the same, the amplitude of accommodation 
 would be greater in hyperopia than in emmetropia. 
 
 In myopia, since a concave lens is necessary ta enable the 
 patient to see distant objects clearly, we must deduct the 
 strength of this glass from that the focal length of which 
 equals the distance of the near point from the eye; for ex- 
 ample, if the myopia equals 2 D. and the near point is 4 
 inches or 10 cm., the amplitude of accommodation will be 4 
 or ^=10 D. — 2 D. =8 D. With the same amplitude of ac- 
 commodation, the near point is closer to the eye in myopia 
 than in emmetropia; and if the near point were the same, the 
 amplitude of accommodation would be less in myopia than in 
 emmetropia. 
 
 The power of accommodation gradually diminishes and the 
 near point recedes as age advances, owing chiefly to loss of elas- 
 ticity of the lens. In the emmetrope at 10 years, the p. p. is 
 at 7 cm. ; at 40 years it has receded to 22 cm. ; at 60 years to 
 100 cm. ; and at 75 years to infinity, the accommodation being 
 suspended and the p. p. coinciding with the p. r. The fol- 
 lowing table gives the amplitude of accommodation and the 
 near point at various periods of life. The near point applies 
 
ACCOMMODATION 
 
 313 
 
 only to emmetropic eyes, but the amplitude of accommodation 
 applies to all eyes, whether emmetropic or ametropic. There is 
 a tendency toward increased amplitude of accommodation in 
 hyperppia and diminished amplitude in uncorrected myopia. 
 
 Year 
 
 Amplitude 
 of Ac- 
 commodation 
 in Diopters 
 
 4 
 
 o 
 
 Hi" 
 
 Year 
 
 Amplitude 
 
 of Ac- 
 commodation 
 in Diopters 
 
 
 III 
 
 10 
 
 14.0 
 
 7.0 
 
 2.8 
 
 45 
 
 3.5 
 
 28.0 
 
 11 
 
 15 
 
 12.0 
 
 8.5 
 
 3.3 
 
 60 
 
 2.5 
 
 40.0 
 
 16 
 
 20 
 
 10.0 
 
 10.0 
 
 4.0 
 
 55 
 
 1.75 
 
 55.0 
 
 22 
 
 25 
 
 8.5 
 
 12.0 
 
 4.7 
 
 60 
 
 1.0 
 
 100 
 
 40 
 
 30 
 
 7.0 
 
 14.0 
 
 5.6 
 
 65 
 
 0.75 
 
 133 
 
 53 
 
 35 
 
 5.5 
 
 18.0 
 
 7.0 
 
 70 
 
 0.25 
 
 400 
 
 160 
 
 40 
 
 4.5 
 
 22.0 
 
 9.0 
 
 75 
 
 0.0 
 
 00 
 
 00 
 
 ■Presbyopia. — ^When the near point of the emmetropic eye 
 has receded to a distance at which the finer kinds of work 
 become difficult, the condition is known as presbyopia (Chap- 
 ter XXIV). This state is the result of a physiological process 
 which affects every eye and must not be considered a disease. 
 It is usually said to be present when the near point recedes 
 to a distance of more than 22 cm. (9 inches) from the eye, 
 an event which generally happens between the fortieth and the 
 forty-fifth years. 
 
 The Association Between Accommodation and Conver- 
 gence. — The preceding considerations of the subject of ac- 
 commodation referred to monocular vision or sight with one 
 eye. With binocular vision it is necessary to consider converg- 
 ence as well as accommodation, for these two actions (together 
 with the contraction of the pupil) are normally associated. 
 
 Convergence is the power of directing the visual lines of the 
 two eyes to a near point, and results from the action of the 
 internal recti muscles. When we look at a distant object ac- 
 commodation is at rest and the visual lines are parallel. 
 When we look at a near object, we are compelled both to ac- 
 commodate and to converge for that distance; vnth a certain 
 
314 OPTICAL CONSIDERATION OF THE EYE 
 
 amount of accommodation, a corresponding effort of convergence 
 of the visual lines is associaied. 
 
 The angle which the visual line makes in turning from a 
 
 distant object to a near one is called the angle of convergence. 
 
 The unit of convergence is the meter angle (M.A.), which is 
 
 the angle formed by the visual Une with the median line at a 
 
 J- , distance of 1 meter (Fig. 288). If 
 
 ^3|_l?— 1^ -:« the eyes look at an object half a 
 
 ^3L??^ loo meter distant the convergence is 
 
 twice that of the unit, and converg- 
 ence (C.) = 2 M.A.; if directed to- 
 ward a point one-third of a meter 
 distant, C. =3 M.A.; if toward an 
 -i^2 MA object 2 meters distant, C. = f M. A. 
 pigT 288!— Diagram Illustrating The emmetropic eye requires for 
 
 the Unit of Convergence, the gg^gjj distance of biuOCular visioU 
 Meter Angle. , , . 
 
 as many meter angles oi converg- 
 ence as it needs diopters of accommodation. To see an object 
 at 1 meter distance, 1 meter angle of convergence is required 
 and also 1 diopter of accommodation; at 10 cm., 10 meter 
 angles of convergence and 10 D. of accommodation would 
 be required. 
 
 This harmonious relationship between accommodation and 
 convergence is not, however, unchangeable. Within certain 
 limits either of these actions may take place independently of 
 the other. 
 
 The Range or Amplitude of Convergence. — ^The far point 
 of convergence is the point to which the visual lines are directed 
 when convergence is at rest; the near point of convergence is 
 the point to which the visual lines are directed with the maxi- 
 mum amount of convergence. The distance between the far 
 point and the near point of convergence is the amplitude of 
 convergence; it is expressed by the greatest number of meter 
 angles of convergence of which the eyes are capable. In a 
 state of rest the far point of convergence is at infinity and 
 the visual lines are either parallel or more commonly some- 
 what divergent, in which case convergence is spoken of asnegor 
 live. In cases of convergent squint, the visual lines deviate in- 
 
AMPLITUDE OF CONVERGENCE 315 
 
 ward even when convergence is relaxed; convergence is then 
 said to be positive. In a case of divergent squint convergence is 
 a negative quantity. Normally, the eyes diverge during sleep. 
 
 Methods of Determining the State of Refraction 
 of the Eye. — There are three principal methods of testing 
 the refraction of the eye: (1) the subjective method, in which 
 the refraction is estimated by the acuteness of vision with 
 test types and trial lenses; (2) the ophthalmoscope; and (3) 
 retinoscopy ; the last two are objective methods. 
 
 Every examination should be undertaken in a systematic 
 manner. We begin with the external examination of the eyes 
 as described in Chapter I. Next the patient is taken into the 
 dark room and the media and fundus are examined with 
 oblique illumination and the ophthalmoscope (Chapter III). 
 Then the state of the refraction is determined with the oph- 
 thalmoscope. The retinoscopic mirror is now employed to 
 estimate the state of the refraction with the shadow test; 
 and the ophthalmometer may also be brought into service. 
 Finally, the patient is examined by the subjective method with 
 test lenses and test types. By employing this order we will 
 save time, since the ophthalmoscopic examination may show 
 changes in the media or fundus which convince us of the 
 impossibility of improving the patient's vision with glasses, 
 or lead us to be satisfied with a limited result. The objective 
 methods of determining the state of refraction of the eye give 
 very close and accurate results; the subjective method serves 
 to verify these conclusions and often perfects them. 
 
 THE DETERMINATION OF THE STATE OE BEFBAC- 
 
 TION BY TEST TYPES AND LENSES (THE 
 
 StJBJEOTIVE METHOD) 
 
 After having determined the acuteness of vision for dis- 
 tance as described on page 12, we endeavor to ascertain which 
 lenses are necessary to correct any error of refraction and to 
 bring the vision up to the normal ^. The patient is placed 
 in front of the test ts^es, which must be well illuminated by 
 daylight or artificial light, at a distance of 20 feet. The 
 trial frame (Fig. 289) is worn by the patient, and the left 
 
316 OPTICAL CONSIDERATION OF THE EYE 
 
 eye excluded by means of a solid metal disc. After testing 
 the right eye, we proceed with the left. 
 
 If the patient reads §, we may assume the absence of 
 myopia; the patient is either emmetropic or he has hyperopia 
 or astigmatism. A weak convex spherical lens (+0-50 D. 
 Sph.) is held in front of the eye; if he is still able to read the 
 25 line as well as without a lens, he has hyperopia, and the 
 strongest convex spherical lens with which he can read ■^ is 
 the measure of his manifest hyperopia. Even though he ac- 
 cepts a convex spherical lens, this is probably not the measure 
 of his total hyperopia, which can be estimated in young per- 
 sons only after the eye has been placed under the effects of a 
 
 Fig. 289. — The Trial Frame. 
 
 cycloplegic. The difference between the manifest and the total 
 hyperopia is known as the latent hyperopia; it is this portion 
 which is discovered after accommodation has been paralyzed. 
 
 If the patient reads f§, and a weak convex spherical lens 
 blurs his vision, he is either emmetropic or has hyperopia 
 which is latent. 
 
 If the patient's vision is below normal, and instead of read- 
 ing §, he reads § or ^, he either has considerable manifest 
 hyperopia, or else he is myopic or astigmatic; or he may have a 
 combination of these errors. If hyperopic, spherical lenses 
 will improve his vision. If such improvement does not result 
 upon placing convex spherical lenses before the eye, we may 
 try a weak concave spherical lens; if this aids his vision, he 
 is myopic, and the weakest concave spherical lens that brings 
 his vision io f is the measure of his myopia. If concave 
 spherical' lenses do not improve the vision, we assume the 
 
SUBJECTIVE TESTING OF REFRACTION 317 
 
 existence of astigmatism; and cylinders, alone or in combina- 
 tion with spherical lenses, are placed in front of the eye for 
 the purpose of estimating the kind, the axis, and the amount 
 of astigmatism. 
 
 This is, briefly, the method pursued in determining the 
 state of refraction by means of the acuteness of vision (sw6- 
 jectively); greater details will be supplied in discussing the 
 errors of refraction. But, as alr.eady pointed out, it is better 
 and saves time to precede this subjective test by the objective 
 methods, using the former to confirm the findings of the 
 others; this is especially advisable if the error of refraction be 
 a diflnicult or complicated one. 
 
 The Vision for Near is also tested. A page of Jaeger's test 
 types (Fig. 18) is given to the patient, and we note the small- 
 est type which he is able to read with each eye separately, the 
 distance which he selects, and the nearest and farthest dis- 
 tances at which he is able to read. These data give us valu- 
 able information regarding the state of refraction. In my- 
 opia, the patient will hold the print closer than normal. In 
 presbyopia he will hold it at a greater distance than normal. 
 
 THE OFHTHAIiKOSCOFE AS A HEANS OF DETECTING 
 AND ESTIMATING BEFBACTIVE ERBORS 
 
 The Ophthalmoscope at a Distance gives us qualitative in- 
 formation regarding errors of refraction. When the patient 
 is emmetropic, no details of the fundus will be seen when the 
 light is thrown into the eye from an ophthalmoscope held at 
 a distance of 15 inches. If some part of the disc or vessels 
 is seen, the patient is ametropic. If the examiner moves his 
 head from side to side and the vessels seem to move in the 
 same direction, the case is one of hyperopia (for in hyperopia 
 the rays emerge divergent and the image is a virtual, erect 
 one). If the vessels seem to move in the opposite direction, 
 the case is one of myopia (since in myopia the emerging rays 
 are convergent and form an inverted image). If the vessels 
 of one meridian only are seen, astigmatism is present; this is 
 hyperopic if the vessels move with the movements of the 
 observer's head, myopic if they move in the opposite direc- 
 
318 
 
 OPTICAL CONSIDERATION OF THE EYE 
 
 tion, and mixed if one set move with and the other against 
 them. 
 
 The Indirect Method is not used for determining the 
 amount of error of refraction, but we obtain information of 
 the Jorm of ametropia by noting the size and shape of the 
 inverted image of the disc and its behavior upon withdrawing 
 or approaching the lens before the patient's eye. If no 
 change takes place in the shape and size of the image when 
 we withdraw the lens, the eye is emmetropic. If the shape 
 remains the same but the image becomes smaller when the 
 lens is withdrawn, it indicates hyperopia. If the shape re- 
 mains the same but the image becomes larger on withdrawing 
 the lens, the case is one of myopia. In astigmatism the disc 
 usually appears oval and the shape of its image changes in 
 withdrawing the lens; one diameter decreases or increases, 
 the other remains stationary in simple astigmatism; both in- 
 crease or decrease unequally in compound astigmatism; one 
 increases and the other decreases in mixed astigmatism. 
 
 The Direct Method is a useful means of determining the 
 condition of refraction, and, in case of error, the kind and 
 
 the amount; fairly 
 reliable findings 
 are obtained, but 
 only after consid- 
 er a b le practice. 
 For accurate re- 
 sults, it is neces- 
 sary that the ac- 
 commodation of 
 both patient and observer be in abeyance. The beginner 
 always has difficulty in relaxing his accommodation, and 
 requires considerable training before he masters this necessary 
 step (p. 30). The jiatient's accommodation is suspended by 
 directing him to look at the wall or at a distant object, or, 
 better, by the use of a cycloplegic. The examiner, if ame- 
 tropic, corrects his error by wearing suitable glasses, by 
 having a special correcting lens applied to the sight-hole of 
 the ophthalmoscope, or by subtracting the amount of his 
 
 Fig. 290. — The Estimation of the Refraction by the 
 Direct Method of Ophthalmoscopy. Both patient 
 and observer are emmetropic. 
 
OPHTHALMOSCOPY IN ERRORS OF REFRACTION 319 
 
 error from the result which he obtains in the examination. 
 The examination is conducted in the manner described on 
 page 28 ; for accurate results it is essential that the shortest 
 possible distance separate the eye of the patient from that 
 of the observer. 
 
 Emmetropia. — The examiner selects a blood-vessel at the 
 outer margin of the disc or between the disc and the macula. 
 If the vessel appears distinct, and if upon rotating a + 0.50 
 D. lens before the sight-hole it becomes blurred, the eye is 
 emmetropic. Rays coming from an emmetropic eye at rest 
 are parallel, and the observing eye will focus these rays on 
 the retina (Fig. 290). 
 
 Hyperopia. — If the image is blurred, we rotate the lens disc 
 of the ophthalmoscope so as to place convex lenses in the 
 sight-hole; if these render the image distinct the eye is hyper- 
 opic. The strongest convex lens with which we get a distinct 
 image is the measure of the hyperopia. In Fig. 291, H is the 
 hyperopic eye under examination, and E the emmetropic eye 
 of the observer. Rays from a emerge divergent as though 
 
 Fig. 291. — The Estimation of Hyperopia by the Direct Method 
 of Ophthalmoscopy. 
 
 coming from x. The convex lens + L makes them parallel 
 so that they focus at 6, on the retina of E, the emmetropic 
 eye of the observer. 
 
 Myopia.— li when the image appears blurred, a convex lens 
 makes it more indistinct, we- rotate the disc of the ophthalmo- 
 scope so that concave lenses are brought opposite the sight- 
 hole. If these render the image distinct, the eye is myopic. 
 The weakest concave lens is the measure of the myopia. We 
 stop at the weakest concave lens which accomplishes this, 
 since stronger lenses of this sort would only encourage the 
 
320 OPTICAL CONSIDERATION OF THE EYE 
 
 observer to accommodate. In Fig. 292, M is the myopic 
 eye under examination, and E the emmetropic eye of the 
 observer. Rays from a leave the myopic eye convergent and 
 would meet at X. The concave lens — L renders them parallel 
 so that they are focussed at h, on the retina of the observer. 
 
 Fig. 292. — The Estimation of Myopia by the Direct Method 
 of Ophthalmoscopy. 
 
 Astigmatism. — ^We find the lens with which a small vertical 
 vessel is seen distinctly, and then the lens which enables a 
 small vessel at right angles to be seen clearly, always remem- 
 bering that the lens which clears up the image of a vessel in 
 one direction is the measure of the refractive error of the 
 meridian at right angles to it. 
 
 Suppose the horizontal vessels appear distinct without any 
 lens — ^then the vertical meridian is emmetropic; and that the 
 vertical vessels require a convex or a concave lens to render 
 them distinct — ^then the horizontal meridian is hyperopia or 
 myopic; the case is one of simple hyperopic or myopic astig- 
 matism (Figs. 310 and 311). 
 
 If both vertical and horizontal vessels are rendered distinct 
 by convex lenses but a stronger one can be used for the hori- 
 zontal, the case is one of compound hyperopic astigmatism 
 (Fig. 312) with the vertical meridian the more hypermetropic; 
 if both vertical and horizontal vessels are best seen with con- 
 cave lenses but of different strength, the case is one of com- 
 pound myopic astigmatism (Fig. 313). 
 
 If the vertical vessels can be seen clearly with a convex 
 lens and the horizontal vessels require a concave lens, the 
 case is one of mixed astigmatism (Fig. 314), the horizontal 
 meridian being hyperopic, the vertical meridian myopic. 
 
THE SHADOW TEST 
 
 321 
 
 RETINOSCOPY 
 
 Retinoscopy {The Shadow Test, Skiascopy) is a very accu- 
 rate, objective method of determining the state of the refrac- 
 tion by illuminating the eye with a plane or concave mirror, 
 and observing the direction of the movement of the retinal 
 illumination and its bordering shadows, when the mirror is 
 rotated. The shadow test has many advantages: It can be 
 used in children, illiterates, and in markedly defective sight; 
 it is entirely objective, and hence requires no co-operation on 
 the part of the patient; it is quick and accurate; and it requires 
 no expensive apparatus. 
 
 The Principle of Retinoscopy is the finding of the point of 
 reversal or the myopic far point. In myopia an inverted image 
 is formed in, the air in front of the eye at the far point — ^the 
 distance from which rays would be focussed on the retina; 
 this point is known as the point of reversal. If the eye is 
 hjTJeropic or emmetropic, a convex lens is placed before it so 
 as to give it an artificial far point. 
 
 When light is thrown into the eye by means of a 
 plane or concave mirror at a distance of one meter, the 
 fundus is illu- 
 minated. B y 
 looking through 
 the sight-hole of 
 the mirror an ob- 
 server will see 
 the illuminated 
 portion (red fun- 
 dus reflex) and 
 also the shadow 
 bounding this 
 bright area. On 
 rotating the mir- 
 ror the illumi- 
 nated area and the shadow will move across the pupil. 
 
 The examination is conducted in the dark room, the darker 
 the better. The source of illumination is placed above the 
 head of the patient and somewhat behind so that his face is 
 
 Fig. 293. — Ketinoscopic 
 Mirror. 
 
 FK. 294.— Small Ketino- 
 scopic Mirror upon 
 Metal Disc. 
 
322 
 
 OPTICAL CONSIDERATION OF THE EYE 
 
 in darkness (Fig. 295, A). An Argand burner is the most 
 common form of illumination; it is often surrounded by an 
 asbestos chimney with a large circular opening opposite the 
 brightest part of the flame, so that the light is thrown only 
 toward the observer. Some oculists prefer the light placed 
 near the observer, about 6 inches to his left and in front, with 
 a small (10 mm.) opening in the opaque chimney (Fig. 295, B). 
 Either a plane or a concave mirror may be employed; the 
 plane mirror has certain advantages and is more commonly 
 used. The retinoscopic mirror (Fig. 293) usually has a diam- 
 eter of 3.5 cm. with a 3 mm. opening, though sometimes a 2 
 
 Fig. 295. — The Retinoscopic Examination. 
 
 cm. mirror upon a 4 cm. metal disc (Fig. 294), with a 2 mm. 
 opening, is preferred, especially if the light is placed near the 
 observer. 
 
 The patient is seated, his pupils are dilated, and preferably 
 his accommodation should be paralyzed. He is directed to 
 look at the forehead of the examiner, just above the mirror. 
 Each eye is tested separately, and one eye is usually covered. 
 
 The observer is seated at one meter distance (Fig. 295) ; he 
 should wear correcting lenses if ametropic; he need not relax 
 his accommodation as in using the ophthalmoscope, since this 
 does not influence the result. 
 
RETINOSCOPY 
 
 323 
 
 If now the mirror be rotated slowly from side to side on its 
 vertical axis, so that the light moves across the pupil horizon- 
 tally, the observer will see an illuminated area and a shadow 
 coming from behind the pupil; if the mirror be rotated on its 
 horizontal axis the light will move across the pupil vertically. 
 The direction of movemerd of this light and shadow as com- 
 pared to that of the mirror depends upon the state of the refrac- 
 tion of the eye. The shadow moves either in the same (with) 
 or the opposite direction (against) to that of the mirror; if we 
 turn the mirror toward the right and the shadow moves 
 toward the right, we say it moves with the mirror; if upon 
 turning the mirror toward the right the shadow moves toward 
 the left, we say it moves against the mirror. With the plane 
 mirror, the shadow moves 
 with the mirror in hyper- 
 opia, emmetropia, and in 
 myopia of less than 1 D., 
 and against the mirror, in 
 myopia of more than 1 D. 
 The illuminated area and 
 the shadow appear to 
 move with the mirror 
 when the observer is 
 within the point of rever- 
 sal, and against the mirror when he is beyond this point. 
 
 Besides the direction of the movement, we acquire informa- 
 tion from the brightness, the form, and the rate of movement of 
 the light and shadow: If the reflex is bright, its edge sharp, 
 and the light and shadow move rapidly, the error of refraction 
 is a low one; if the illumination is dull, its edge indistinct, 
 and the movement of light and shadow slow, the error is a 
 high one. If the shadow has a straight edge it is an indica- 
 tion of astigmatism (Fig. 296); in hyperopia, myopia, or 
 emmetropia, the shadow has a crescentic edge (Fig. 297). 
 
 Next we find the correcting lens — i.e., the lens which causes 
 a reversal of the direction of movement of the shadow. This 
 lens will be correct for the distance separating the observer 
 from the patient, one meter. For infinity, we must add - 1 
 
 Fig. 296.— Retino- 
 scopic Illumination 
 and Shadow in A£- 
 tigmatism. 
 
 Pig. 297. — Retino- 
 scopic Illumination 
 and Shadow in My- 
 opia, Hyperopia, or 
 Emmetropia. 
 
324 OPTICAL CONSIDERATION OF THE EYE 
 
 D. to all results; this increases the myopia 1 D., and dimin- 
 ishes hyperopia 1 D. 
 
 If with the plane retinoscope the shadow moves against the 
 mirror, we place concave spherical lenses before the eye until 
 we succeed in causing a reversal of the movement of the 
 shadow — i.e., cause it to move with the mirror; this lens, to 
 which we add — 1 D., is the measure of the patient's myopia. 
 Suppose on placing —ID. before the eye, the shadow still 
 moves against the mirror, the same with — 2 D., but with 
 
 - 2.50 D. the movement of the shadow is reversed; then 
 
 - 2.50 +-!.= - 3.50 D. is the correction. 
 
 If with the plane retinoscope the shadow moves with the 
 mirror, the eye may be hyperopic, emmetropic, or myopic less 
 than ID. In such a case we begin by adding a convex lens of 
 + 0.50 D. If this causes a reversal of the shadow the eye 
 is myopic 0.50 D., since + 0.50 O - 1.00 = - 0.50 D. 
 
 If the + 0.50 D. lens does not alter the direction of the move- 
 ment of the shadow, but the next lens (+ 1 D.) causes a re- 
 versal, the eye is emmeiropzc, since + 1.00 O — 1.00 =0 = E. 
 
 If the + 1.00 D. lens has no effect upon the direction of 
 movement of the shadow, the eye is hyperopic; we place 
 stronger + spherical lenses before the eye until we find the 
 one which causes a reversal of the movement of the shadow. 
 Say this is + 4 D. ; then the hyperopia amounts to + 4.00 O 
 
 - 1.00 = -1- 3 D. 
 
 In the previous examples, the results were the same whether 
 the mirror was rotated upon its vertical or its horizontal axis. 
 In astigmatism, upon correcting each of the two principal 
 meridians separately, one meridian will require a different 
 lens to cause a reversal of the shadow than the other. The 
 most common positions of the two meridians in astigmatism 
 are vertical and horizontal. But frequently the edges of the 
 shadows lie more or less obliquely. In such cases the mirror 
 must be rotated so that the light moves obliquely and parallel 
 with the movement of the shadow. 
 
 For example, suppose the shadow moves with the mirror in 
 both meridians, but one shadow is more distinct and moves 
 more quickly than the other; we diagnose astigmatism. Then 
 
THE SHADOW TEST 325 
 
 we correct the vertical meridian and find it requires + 1 D. 
 for the reversal of the shadow. Next we find that in the 
 horizontal meridian + 2 D. are required for reversal. We 
 add — 1 D. to each of these results and have + 1 O — 1 = 
 or E in the vertical, and + 20 — l = + lin the horizon- 
 tal meridian. The case is one of simple hyperopic astigmatism 
 and requires for its correction + 1 D. cylinder, axis vertical. 
 
 If in the horizontal meridian — 2D. are required for re- 
 versal, and in the vertical meridian, — 4 D. : Adding — 1 to 
 each, we will have — 3 in the horizontal and — 5 in the 
 vertical meridian. The error of refraction is compound my- 
 opic astigmatism and the correcting sphero-cylinder will be 
 — 3 D. O — 2 D. cyl. axis horizontal. 
 
 Finally, let us take an example of mixed astigmatism: The 
 shadow will move with the mirror in one meridian and against 
 the mirror in the other. If in the vertical meridian the 
 shadow moves with the mirror and -f- 2 D. are required to 
 cause a reversal, and in the horizontal meridian the shadow 
 moves against the mirror and — 2D. effect a reversal, and 
 we add — 1 to each, we obtain + 1 for the vertical and — 3 
 for the horizontal. The correcting lens will be -|- 1 D. 
 Sph. O — 4 D. cyl. axis vertical. 
 
CHAPTER XXIII 
 
 ERRORS OF REFRACTION 
 
 In emmetropia (E.) the eye in a state of rest, without ac- 
 commodation, focusses the image of distant objects exactly 
 upon the retina (Fig. 282); such an eye enjoys distinct vision 
 for distant objects without effort or fatigue. Any variation 
 from this standard constitutes ametropia, a condition in which 
 the eye, in a state of rest, is unable to focus the image of dis- 
 tant objects (parallel rays) upon the retina. Ametropia in- 
 cludes hyperopia, myopia, and astigmatism. The effects of 
 ametropia are not only indistinctness of vision but various 
 pains and other symptoms comprised under the term astheno- 
 pia (weak sight, eye strain). 
 
 HYPEROPIA 
 
 Hyperopia {Hypermetropia, Farsightedness, H.) is an error 
 of refraction in which, with accommodation completely re- 
 laxed, parallel rays (rays from distant objects) are brought to 
 a fociis behind the retina (Figs. 283, 298); divergent rays 
 (from near objects) are focussed still farther back. 
 
 Etiology. — It is most commonly due to shortening of the 
 antero-posterior diameter of the eyeball {axial H.), less fre- 
 quently to diminished convexity of the refracting surfaces of 
 the eye {H. of curvature), changes in the media, or absence of 
 the lens {aphakia). It is by far the most frequent error of 
 refraction and is congenital; in a certain sense it may be con- 
 sidered due to imperfect development of the eye. It is often 
 hereditary. Children are usually hyperopic at birth and sub- 
 sequently become less hyperopic, emmetropic, or even myopic. 
 
 The Course of Rays. — The hyperopic eye caimot, without 
 accommodation, see either distant or near objects distinctly 
 (Fig. 298). In a condition of rest, it is adapted for conver- 
 gent rays, and these are not found in nature. To focus paral- 
 lel rays on the retina it must either accommodate, i.e., increase 
 
 326 
 
HYPEROPIA 
 
 327 
 
 the convexity of its lens as shown in Fig. 299, or a convex lens 
 of such a strength that the rays are made sufficiently conver- 
 gent to be brought to a focus on the retina (Fig. 300) must 
 
 be placed in front of the eye. 
 
 To focus divergent rays, 
 
 i.e., rays from near objects, 
 
 the hyperope must not only 
 
 Fig. 298. — Hyperopic Eye in a State 
 
 of Kest. 
 Fig. 299. — Hyperopic Eye during 
 
 Accommodation. 
 Fig. 300. — Hyperopia Corrected by 
 
 a Convex Lens. 
 
 Fig. 301. — Emmetropic Eye 
 
 Accommodating for Near 
 
 Vision. 
 Fig. 302. — Hyperopic Eye 
 
 Accommodating for Near 
 
 Vision. 
 
 accommodate the amount required of an emmetropic eye 
 (Fig. 301), but an additional amount to compensate for his 
 error. In other words, he requires some accommodation 
 constantly in order to see distant objects distinctly, and in 
 addition the amount equal to that required by the emme- 
 trope for near vision (Fig. 302). Such an eye (when the 
 error is uncorrected) is never in a condition of rest as long as 
 it enjoys distinct vision. 
 
 Changes in the Eye.— As a result of the constant strain and 
 overaction of the ciliary muscle, the latter becomes hypertro- 
 phied, especially its circular fibres (Fig. 304) ; it remains in a 
 greater or lesser condition of spasm. In high degrees of H. 
 the eyeball may be diminished in size, the anterior chamber 
 shallow, the sclera flat with a sharp curve at the equator, and 
 
328 
 
 ERRORS OF REFRACTION 
 
 Fig. 303. Fig. 304. Fig. 305. 
 
 Fig. 303. — Section of the Ciliary Muscle in an 
 
 Emmetropic Eye. 
 Fig. 304. — Section of the Ciliary Muscle in a 
 
 Hyperopic Eye. 
 Fig. 305.— Section of the Ciliary Muscle in a 
 
 Myopic Eye. 
 
 there may be an apparent external squint, owing to the high 
 angle gamma (see p. 309). 
 
 Varieties. — Hyperopia is divided into (1) manifest, (2) 
 latent, and (3) total. 
 
 (1) The manifest hyperopia (Hm.) is that which is de- 
 tected without paralyzing the accommodation and is repre- 
 sented by the strongest 
 convex glass with which 
 the patient sees most dis- 
 tinctly; it corresponds to 
 the amount of accommo- 
 dation which he relaxes 
 when a convex lens is 
 placed before the eye. 
 Manifest hyperopia may 
 be either facultative, when 
 it can be overcome by an 
 effort of accommodation, 
 
 or absolvie, when it cannot be overcome in this manner. 
 
 (2) The total hyperopia (Ht.) is the entire amount of hyper- 
 opia detected after the accommodation has been paralyzed or 
 during complete relaxation of the ciliary muscle. 
 
 (3) The latent hyperopia (HI.) is the difference between the 
 Hm. and the Ht., and is the amount which is habitually con- 
 cealed and is discovered only after the use of a cycloplegic. 
 
 The application of these terms can be illustrated by con- 
 sidering an example of H. of 2.5 D. in a young person. If in 
 such a case V = jg, and, without the use of a cycloplegic, a 
 + 1 D. spherical lens brings up the vision to ^, we say Hm. 
 = ID.; if now we paralyze the accommodation with a cyclo- 
 plegic and find V = joo, and that a + 2.50 D. spherical lens 
 increases this to f, theHt. = 2.50 D.; the difference between 
 2.50 D. and 1.00 D. = 1.50 D.= HI. 
 
 The ratio between the manifest and the latent hyperopia is 
 not constant; it depends more or less upon the age and vigor 
 of the individual. In youth, the amount of HI. is apt to be 
 considerable, and consequently a cycloplegic is essential in 
 estimating the amount of hyperopia. The older a person 
 
SYMPTOMS OF HYPEROPIA 329 
 
 grows, the less accommodative effort he is able to make; 
 hence the HI. becomes less, and the Hm. greater. In old 
 persons there is no HI., the total hyperopia becoming manifest. 
 
 Symptoms. — Unless the error be considerable or the pa- 
 tient be advanced in years, there is usually good vision jor 
 distance. A great many patients with hyperopia present no 
 symptoms whatever; this is apt to be the case when the 
 hyperope is young and in good health. In other cases, the 
 accommodative efforts will be unequal to the task imposed 
 in near work, and as a result the hyperopia will give rise to 
 accommodative asthenopia (weak sight, eye strain). 
 
 The Symptoms of Asthenopia show themselves particularly 
 after reading, writing, sewing, and other forms of near appli- 
 cation, especially in the evening and with artificial illumina- 
 tion. They comprise pain referred to the eyes or above the 
 eyes; headaches, usually frontal, but also occurring in the 
 occiput and other parts of the cranium; various neuralgias; 
 congestion of the conjunctiva and margins of the lids; lacrjTna- 
 tion, blinking, and slight photophobia; burning sensation in the 
 lids; and blurring of near vision. These symptoms are more 
 pronounced whenever the general health is unsatisfactory. 
 
 With advancing years, there will be greater difficulty in 
 reading without correcting glasses. 
 
 In early childhood, h3rperopia often causes convergent squint 
 in a patient whose fusion sense is deficient (p. 374). 
 
 In children, H. shows a physiological tendency to diminish 
 with the growth of the child; after puberty it may become 
 greater. In the adult it remains stationary; after fifty there 
 is a tendency to a slight increase. 
 
 Hyperopic eyes are predisposed to conjunctivitis and ble- 
 pharitis, phlyctenular affections, congestion of the retina and 
 choroid, internal squint, and glaucoma. 
 
 Tests. — These have been described in the preceding chap- 
 ter. They are the following: 
 
 The Subjective Test with Test Types and Test Lenses. — ^We 
 first record the acuteness of vision and then place convex 
 lenses before the eye, commencing with -F 0.50 D. The 
 strongest lens with which the patient sees ^ or better is 
 
330 ERRORS OF REFRACTION 
 
 the measure of the manifest hyperopia. Then the accommo- 
 dation is paralyzed and the test repeated; the strongest lens 
 " accepted " {i.e., with which the patient's vision is im- 
 proved) is the measure of his total hyperopia. Such an 
 examination is recorded as follows: 
 
 0. D. V = i; Hm. 0.50 D.; Hom: V = i; i w. -f 2 
 D. S. Translated, this line would read : Oculus dexter (right 
 eye), vision equals |; manifest hyperopia 0.50 D.; after the 
 use of homatropine, vision equals ^, increased to 20 with a 
 convex spherical lens of 2 diopters. 
 
 The Ophthalmoscope at a Distance. — The retinal vessels ap- 
 pear to move in the same direction as the observer's head. 
 
 The Ophthalmoscope, Indirect Method. — On withdrawing the 
 lens in front of the patient's eye, the size of the disc diminishes. 
 
 The Ophthalmoscope, Direct Method. — The disc and vessels 
 can be seen distinctly with a convex lens in the sight-hole, 
 the strongest being the measure of the H. 
 
 Retinoscopy. — With the plane mirror held at one meter, the 
 shadow moves with the mirror; the direction of movement is 
 reversed by convex lenses placed in front of the patient's eye. 
 The lens which causes a reversal, minus 1 D., is the measure 
 of the H. 
 
 Treatment corisists in prescribing such convex spherical 
 lenses as will make vision distinct and enable the patient to do 
 near work without fatigue. The mere existence of hyperopia 
 is no indication for the use of correcting glasses unless these 
 are worn in childhood for the cure of convergent squint. It 
 is only when there is a diminution in the acuteness of vision 
 or when symptoms arise indicating eye strain that convex 
 lenses should be used. 
 
 Though theoretically it would seem proper to prescribe the 
 full correction (for Ht.), practically there are many objections 
 and exceptions to this. In every case of hyperopia occurring 
 in children and in young adults, the accommodation should be 
 paralyzed and the total error estimated so as to serve as a 
 basis for the prescription for glasses. 
 
 The symptoms of the individual give us reliable indications 
 as to the proportion of the Ht. which ought to be corrected, 
 
THE CORRECTION OF HYPEROPIA 331 
 
 and the constancy with which the glasses should be worn. In 
 cases of squint, and when glasses are prescribed for the relief 
 of conjunctivitis, blepharitis, and headaches which are con- 
 tinuous, or the occurrence of which is independent of near use 
 of the eyes, they must be worn constantly. In other cases, 
 glasses should be worn continuously or only for near, accord- 
 ing to whether the symptoms are always present or follow 
 only after using the eyes for reading and the like. When 
 distant vision is perfect and comfortable, and the patient does 
 not suffer from any symptoms except when engaged in near 
 work, glasses need be prescribed only for such use; this is 
 often the case in young adults who eiijoy good health. Under 
 such circumstances, the correction of the Hm. may be suffi- 
 cient; or we may add to this the correction for part of the 
 . HI., or we may correct the Ht. In cases in which the correc- 
 tion is only partial, the glasses may require changing from 
 time to time. In hyperopes after forty-five, convex lenses 
 should be worn to improve distant vision, and a stronger pair 
 for near; the weaker set is for the H., the stronger pair to 
 correct both the hyperopia and the presbyopia. Under such 
 circumstances, bifocal lenses (Fig. 325) are very convenient, 
 the upper segment corresponding to the weaker glass, the 
 lower to the stronger. 
 
 MYOPIA 
 
 Myopia (Nearsightedness, Shortsightedness, M.) is that re- 
 fractive condition in which, with accommodation completely 
 relaxed, parallel rays are brought to a focus in front of the 
 retina. These rays cross in the vitreous; when they reach 
 the retina they have become divergent, forming a circle of 
 diffusion and consequently a blurred image (Fig. 306, PPF). 
 Certain divergent rays, coming from the myopic far point, are 
 focussed on the retina (Fig. 306, DX) without accommodation. 
 , The greatest distance at which the patient can read fine 
 print is the far -point. This is always at a definite distance 
 corresponding to the amount of M.; the higher the M., the 
 closer to the eye is the far point; the distance of the latter is 
 the measure of the M. For example, if the far point is at 20 
 
332 
 
 ERRORS OF REFRACTION 
 
 Fig. 306. — ^The Focussing of Par- 
 allel and Divergent Rays in 
 Myopia. 
 
 Fig. 307. — The Correction of 
 Myopia by Means of a Concave 
 Lens. 
 
 inches (.5 meter) the M. = 2 D. (| or w = 2); if at 10 
 inches (.25 meter) the M. = 4 D. In these two instances 
 concave lenses of 2 and 4 D. respectively would render paral- 
 lel rays as divergent as if they 
 came from a distance of 20 and 
 10 inches (.5 and .25 meter) ; and 
 with these lenses, the myope 
 would be able to see distant ob- 
 jects distinctly (Fig. 307) 
 
 Etiology. — Myopia almost al- 
 ways depends upon a lengthening 
 of the antero-posterior diameter 
 of the eyeball . {axial myopia); 
 in M. of 3 D., for example, the 
 eyeball measures 24 mm. in its 
 antero-posterior diameter, and in 
 M. of 10 D., 27 mm. from before 
 backward, instead of 23 mm., 
 the normal diameter. Much less 
 frequently M. is due to increased cm-vature of the corrifea 
 (anterior staphyloma and keratoconus), increase in the re- 
 fraction of the lens from swelling in incipient cataract, and 
 spasm of accommodation. The determining causes are 
 associated with the demands which civilization and education 
 make upon near vision. It is rarely congenital, though 
 there is often an hereditary tendency for its development. 
 It is an acquired change which commences at an early 
 age when, during the developing period, the eyes are v^ed 
 excessively or improperly for near work. Its occurrence is in 
 direct proportion to the standard of education, and also bears 
 a certain relation to the general health and strength of the 
 individual. It is much more common in cities than in the 
 country. It increases in percentage from the lower to the 
 higher classes in schools and universities. 
 
 Excessive study with insufficient outdoor exercise, fine or 
 indistinct print, poor illumination, opacities of the cornea and 
 other lesions causing imperfect vision, faulty construction of 
 desks, sedentary habits, and poor health are among the fre- 
 
ETIOLOGY OF MYOPIA 333 
 
 quent exciting causes of myopia, especially in those who are 
 predisposed. 
 
 The cause of the lengthening of the eyeball is attributed (1) 
 to pressure of the extraocular muscles during excessive con- 
 vergence causing the posterior pole, which is the least resist- 
 ant part of the eyeball, to bulge; (2) to congestion, inflam- 
 mation, and softening of the layers of the eyeball, together 
 with increased tension, produced by fulness of the veins of 
 the head as a result of stooping postures and other predispos- 
 ing causes; and (3) to the shape of the orbit in broad faces 
 causing "excessive convergence, as seen in the German race, 
 which is especially subject to this error of refraction. 
 
 Clinical Forms. — In most instances, myopia is of low degree, 
 develops during youth, and then comes to a standstill or in- 
 creases very little; this is known as stationary or simple 
 myopia. 
 
 In other cases, the error reaches a considerable height in 
 youth, and increases steadily up to the twenty-fifth year or 
 even later, resulting in a high degree of myopia; this is known 
 as progressive myopia. These are the cases which are ac- 
 companied by destructive changes in the choroid and other 
 parts of the eye, leading to a considerable impairment of 
 vision, and in which myopia may properly be considered a 
 disease. Extreme cases of progressive myopia are known as 
 malignant myopia. 
 
 Symptoms depend on the degree of myopia. 
 
 In slight degrees and in many cases of moderate amount, 
 there are often no symptoms except indistinct vision for dis- 
 tance. Near work can be accomplished with comfort ; in fact, 
 since the myope requires less accommodation than the emme- 
 trope, he may have an advantage in close application. It is 
 on this account that the circular fibres of the ciliary muscle 
 are less developed than in the emmetropic eye (Fig. 305). 
 
 In other cases of moderate myopia and in high degrees, dis- 
 tant vision is very indistinct; there is often pain in the eyes 
 after near use; the patient will be unable to continue at work 
 for any length of time on account of excessive convergence; 
 the eyes tire easily, are sensitive to light, and irritable; there 
 
334 ERRORS OF REFRACTION 
 
 are black spots before the eyes (muscse volitantes), and some- 
 times bright flashes of light. In some cases there may be 
 absolute scotomata. 
 
 In high myopia, there are often prominence of the eyes, a 
 deep anterior chamber, and dilated pupils; the patient is apt 
 to screw the eyelids together; there is sometimes an appear- 
 ance of convergence. The strain of excessive convergence is 
 so great and painful, that the effort is sometimes given up and 
 divergent squint results. 
 
 Ophthalmoscopic Signs, — In low (less than 3 D.) or mod- 
 erate (3 to 6 D.) degrees, there are frequently no changes 
 except a crescent-shaped patch of atrophy of the choroid of 
 whitish or grayish-color, embracing the outer side of the disc; 
 this is called a myopic crescent. 
 
 In high myopia (more than 6 D.), a well-marked crescent is 
 usually found, often posterior staphyloma (bulging of the 
 sclera. Fig. 177, Plate XIV), and there may be patches of 
 choroidal atrophy with pigmented margins, exposing the 
 sclera. In progressive cases, there are frequently added to 
 these lesions atrophic and pigment changes in the macular 
 region (Fig. 174, Plate XIII), hemorrhages, especially at, the 
 yellow spot, fluid vitreous (causing tremulous iris), opacities 
 of the vitreous and of the lens; sometimes there is detachment 
 of the retina. Owing to these changes, the vision is often 
 very markedly reduced and is sometimes lost in severe forms 
 of progressive myopia. 
 
 Tests. — The Subjective Test with Test Types and Test 
 Lenses. Distant vision is below the normal and the patient 
 requires a concave spherical lens to bring the sight up to jo- 
 The weakest lens which accomplishes this is the measure of 
 the myopia. In yoimg persons it is important to paralyze 
 the ciliary muscle, so that spasm of accommodation will not 
 cause the patient to select too strong a lens. The results are 
 recorded as follows: O.D. V = .|^; i w.- 4 D. Sph. The 
 reduction in distant vision generally corresponds to the 
 amount of M. 
 
 The myope is able to read the smallest print, but at a 
 shorter distance than that which the emmetrope selects. The 
 
TESTS FOR MYOPIA 335 
 
 farthest distance at which he is able to read the finest print is 
 his jar 'point, and this is also the measure of his M. 
 
 The Ophthalmoscope at a Distance shows an inverted image 
 of the fundus which appears to move in the opposite direction 
 to the examiner's head. 
 
 The Ophthalmoscope, Indirect Method. — The disc appears 
 small and seems to increase in size upon withdrawing the 
 objective lens. 
 
 The Ophthalmoscope, Direct Method. — The fundus cannot 
 be distinctly seen until a concave lens is placed behind the 
 mirror; the weakest concave lens with which the details are 
 seen clearly, indicates the amount of myopia. 
 
 Retinoscopy. — ^With the plane mirror and the observer at 1 
 meter distance, the shadow moves in the opposite direction 
 (except when M. is less than 1 D.), and is reversed by the 
 addition of concave lenses. The lens which causes reversal 
 plus — 1 D. is the measure of the M. In high M. the shadow is 
 very faint, but becomes plainer when concave lenses are added. 
 
 Prognosis. — In low and moderate degrees of stationary my- 
 opia, the prognosis is good when suitable glasses are worn. 
 Progressive myopia is always a serious condition, especially 
 when the choroidal and vitreous changes are marked; it fre- 
 quently necessitates absolute cessation of all near work. In 
 malignant myopia the prognosis is grave. 
 
 Treatment consists in prescribing suitable glasses, limiting 
 the amount of work so that there will be no fatigue, and pre- 
 venting the progress of the disease. 
 
 In general terms, it is proper to give a full correction for 
 low and moderate myopia in young persons, as soon as discov- 
 ered, and to direct these glasses to be worn for both distance 
 and near; this places the eyes under normal conditions of 
 vision and accommodation. The glasses must be prescribed 
 after the accommodation has been paralyzed, so that there 
 will be no danger of over-correction on account of spasm of 
 accommodation. Full correction corresponds to the weakest 
 concave spherical lens which, with accommodation paralyzed, 
 gives the best vision. In low degrees of M. an adult may 
 be allowed to read without glasses if he finds this convenient. 
 
336 ERRORS OF REFRACTION 
 
 In high myopia, the full correction is prescribed for dis- 
 tance, and about two-thirds correction for near work; the 
 reading-glasses should be such as to enable the patient to read 
 at a comfortable distance, say 13 inches (33 cm.)- Suppose 
 — 10 D. gives the best Ansion for distance; then — 10 D. -f- 3 
 D. Sph. = — 7 D. will enable him to read at this distance 
 without accommodation. 
 
 After the age of 45, the distance glasses cannot be worn for 
 near work, since the convex lenses usually required for pres- 
 byopia must be added to the concave lenses, thus reducing 
 the strength of the latter. 
 
 In prescribing glasses in M. every case must be considered 
 on its merits. Many myopes wear strong lenses, represent- 
 ing the full correction, constantly and with absolute comfort; 
 others require two sets of lenses, one for distance and a 
 weaker pair for reading. 
 
 In order to check any tendency to increase of M., rigid 
 hygienic rules, both local and general, should be carried out. 
 These are of especial importance in the young. The patient's 
 habits should be regulated to insure good health. He should 
 have an abundance of outdoor exercise and plenty of sleep. 
 
 Near work should be restricted and the patient not be al- 
 lowed to read too long at a time. The book should be held at 
 13 inches (33 cm.). In most cases the full correcting lenses 
 should be worn for near work. The illumination should be 
 good, neither too bright nor too dim, and should come from 
 behind; the myope should avoid reading at dusk or with 
 feeble illumination; the amount of work done with artificial 
 light should be limited. The print should be large and clear, 
 with ample spacing. Desks should be constructed so that 
 the sitting posture is comfortable, and so that the child is not 
 encouraged to stoop over his books; the myope must be 
 taught not to bend over his work, but to lift the latter to the 
 required distance from the eyes. 
 
 If notwithstanding such precautions, myopia progresses, it 
 is necessary to forbid aHjjear use of the eyes. A good plan 
 is to take the patient from school and send him to the country 
 for a long period, during which he is instructed to be out-of- 
 
TREATMENT OP MYOPIA 337 
 
 doors as much as possible, and to avoid all reading and near 
 work. Young adults suffering from progressive myopia 
 should give up sedentary occupations necessitating close appli- 
 cation, and select those in which but little near use of the 
 eyes is required. 
 
 Operative Treatment. — In children and young adults with 
 high myopia, uncomphcated by excessive pathological changes 
 in the fundus, the removal of the lens by discission and subse- 
 quent extraction is frequently very successful. The lens is 
 needled, and after several days the swollen lens substance is 
 removed by extraction. The operation is limited to M.oflU 
 D. or more. After the removal of the lens the eye may be 
 almost emmetropic, since the optical effect in such highly 
 myopic eyes is quite different from that which follows extrac- 
 tion of the lens in the emmetrope; a weak convex glass may be 
 required for distance, and a stronger one for near work since 
 the accommodation has been sacrificed. The operation does 
 not seem to increase or decrease the danger of complications. 
 Suitable cases present themselves much less frequently in 
 America than in Germany, where myopia is very common. 
 
 ASTIGUATISX 
 
 Astigmatism (Astigmia; As.) is that refractive condition of 
 the eye in which there is a difference in degree of refraction 
 in different meridians, so that each will focus parallel rays at 
 a different point (Figs. 310-314). 
 
 In E., H., and M., rays coming from a luminous point are 
 brought to a single focus at a certain distance behind the cor- 
 nea. In astigmatism, since the refractive surfaces are not 
 spherical, rays from a luminous point are brought to a focus 
 at different points; the shape of the image may be a line, an 
 oval, or a circle, but never a point. 
 
 Astigmatism may be (1) Regular, very common, and (2) 
 Irregular, comparatively infrequent. 
 
 Regular Astigmatism is that form in which, though the 
 refraction in a meridian is the same throughout, there is a 
 difference in the degree of refraction in every meridian — the 
 curvature of the cornea is different in different meridians. 
 
338 ERRORS OF REFRACTION 
 
 One meridian exhibits the maximum' and the other the mini- 
 mum refraction; these are called the principal meridians and 
 are always at right angles to each other. The refractive power 
 of all other planes will be regularly intermediate according to 
 their position with regard to the principal meridians. 
 
 Irregular Astigmatism, on the other hand, is that variety 
 in which there is not only a difference in refraction in different 
 meridians, but also in different parts of the same meridian. 
 
 When the term astigmatism is used without qualification, it 
 refers to regular astigmatism. 
 
 Etiology. — Astigmatism is usually due to a change in the 
 curvature of the cornea, with or without some shortening or 
 lengthening of the antero-posterior diameter of the eyeball. 
 It is also caused, in part at least, by defects in the curvature 
 of the lens; this lenticular astigmatism may partly neutralize 
 that of the cornea. It is usually congenital and there is often 
 an hereditary tendency; it may, however, be acquired, and is 
 then caused by corneal changes from inflammation, injury, or 
 operation. Pressure of the lids in ametropia is believed to be 
 capable of producing permanent regular astigmatism. 
 
 Even the normal eye has a slight amount of regular astig- 
 matism, due to the fact that the cornea is the segment, not of 
 a sphere, but of an ellipsoid; consequently there is a sUght 
 difference in the refraction of the two principal meridians, the 
 curvature of the vertical meridian being greater than that of 
 the horizontal; hence the focus of the former is somewhat 
 shorter than that of the latter. 
 
 Refraction of Rays in Regular Astigmatism. — ^Parallel rays 
 refracted by a spherical surface form a circular cone and focus 
 at a point. In astigmatism, those rays which pass through 
 the meridian of greater curvature come to a focus sooner than 
 those which pass through the meridian of lesser curvature; 
 the resulting cone will not be circular, but more or less oval; 
 hence the vision of astigmatic subjects is not simply indis- 
 tinct, but the diffusion images are more or less elongated. 
 
 In looking at straight lines (which are made up of a succes- 
 sion of points), these may appear distinct or indistinct to 
 astigmatic persons according to their direction. If an astig- 
 
REFRACTION IN ASTIGMATISM 
 
 339 
 
 matic eye, in which the vertical meridian is out of focus and 
 the horizontal meridian normal, looks at a vertical line, this 
 will be slightly elongated; but the sides will appear distinct, 
 since each point of Ught will be seen as a small vertical line, 
 and these overlap each other. 
 But if such an eye looks at a 
 horizontal line, each point, of light 
 will again be seen as a small ver- 
 tical line, and consequently the 
 hne will appear blurred (Fig. 308) . 
 There is, therefore, one direction 
 in which straight lines appear 
 most distinct, and another at 
 right angles to it, in which they 
 appear most indistinct; this 
 
 Fig. 308. Fig. 309. 
 
 Fig. 308.— Vertical and Horizontal 
 Lines as Seen by an Astigmatic 
 Eye in which the Horizontal Merid- 
 ian is Emmetropic. 
 Fig. 309. — ^Vertical and Horizontal 
 Lines as Seen by an Astigmatic 
 . 1 1 . !• 1 ^y® ™ which the Vertical Meridian 
 
 lorms the basis for the construe- ig Emmetropic. 
 
 tion of the astigmatic dial or fan 
 
 (Fig. 315) commonly used as a test for this error. The 
 
 lines 'parallel with the ametropic meridian are seen most clearly, 
 
 and those parallel with the emmetropic meridian are seen most 
 
 indistinctly (in simple- As.). 
 
 Varieties of Regular Astigmatism. — ^According to the refrac- 
 tion of the principal meridians, astigmatism is divided into : 
 
 1. Simple, in which one meridian is emmetropic and the 
 
 Fig. 310. — Simple Hyperoplc Astigma- 
 tism. 
 
 Fig. 311. — Simple Myopic Astigma- 
 
 other hyperopia or myopic; it comprises simple hyperopia 
 astigmatism (H. As., Fig. 310), and simple myopic astigma- 
 tism (M. As., Fig. 311). 
 
 2. Compound, in which both meridians are either hyperopia 
 or myopic, but unequal in degree; it comprises compound hy- 
 peropia astigmatism (H. -|- H. As., Fig. 312), and compound 
 myopic astigmatism (M. + M. As., Fig. 313). 
 
340 
 
 ERRORS OF KEf RACTION 
 
 3. Mixed, in which one meridian is hyperopic and the other 
 myopic (H. As. + M. As., Fig. 314). 
 
 In most cases of astigmatism, the cornea presents its 
 
 Fig. 314. — Mixed Astigmatism. 
 
 Fi'p. 312. — Compound Hyperopic Astigma- Fig. 313. — Compound Myopic Astigma- 
 tism.- tism. 
 
 maximum curvature in or near the vertical m£ridian and 
 the least curvature in or near the horizontal meridian, cor- 
 responding to the slight astig- 
 matism of the normal eye; 
 when this is the case, it is said 
 to be astigmatism with the rule; 
 when the relative curvatures 
 are reversed, it is astigmatism 
 against the rule. In astigma- 
 tism with the rule the axis of tjie cylinder is vertical or 
 nearly so in hyperopic astigmatism, and horizontal or nearly 
 so in myopic astigmatism. The chief meridians, though 
 vertical and horizontal in the majority of cases, may occupy 
 an obliqu£ position; in such cases they are most frequently 
 symmetrical, i.e., inclined an equal number of degrees from 
 the vertical or horizontal on each side. 
 
 Symptoms.— There is always a diminution in the acuteness 
 of vision both distant and near, varying with the degree and 
 variety of astigmatism; it is least with simple astigmatism, 
 more with compound astigmatism, most with mixed astig- 
 matism. There is commonly considerable asthenopia, espe- 
 cially upon use of the eyes for near work. These asthenopic 
 sjonptoms are similar to those occurring in hyperopia (p. 329), 
 but are apt to be more pronounced and continuous. They 
 vary with the degree and variety of astigmatism, the amount 
 of near work indulged in, and especially the state of the 
 patient's health; a small amount (0.50 D. or even 0.25 D.) 
 
SYMPTOMS OF ASTIGMATISM 
 
 341 
 
 will, for instance, often give rise to severe asthenopic and 
 nervous symptoms in a young, delicate, neurasthenic indi- 
 vidual. The involuntary accommodative efforts of the ciliary 
 muscle, made to diminish the effects of the error, cause con- 
 tinuous eye strain axxd explain the frequency, of asthenopia. 
 
 Tests. — We usually suspect astigmatism when vision cannot 
 be brought up to ^ with spherical lenses, notwithstanding the 
 fundus is normal and the media are clear. In testing for 
 astigmatism in children and in young adults, sometimes even 
 in adults of forty, and occasionally after this age, it is neces- 
 sary to have the eye imder the influence of a cycloplegic; 
 otherwise the results are apt to be unsatisfactory. 
 
 The Astigmatic Dial. — The diagnosis of astigmatism is 
 made if the patient, when placed before the astigmatic dial or 
 fan (formed of radiating lines 
 mmibered like the face of a clock, 
 Fig. 315), is unable to see all the 
 lines with equal distinctness. The 
 line seen most distinctly and the 
 line seen least distinctly indicate 
 the axes of the two principal merid- 
 ians; the axis of the former cor- 
 responds to the ametropic merid- 
 ian, that of the latter to the 
 enunetropic meridian (in simple 
 astigmatism). 
 
 Suppose in an example of simple astigmatism, the patient 
 sees lines XII and VI most distinctly and those at right an- 
 gles, IX and III, least clearly; then the ametropic meridian 
 is vertical. If a weak convex lens placed in front of the eye 
 makes lines XII and VI indistinct, we know that the hori- 
 zontal meridian is emmetropic. Next we find which spheri- 
 cal lens clears up lines IX and ///; this glass is the measure 
 of the refractive error of the vertical (ametropic) meridian. 
 
 The Metal Disc with Stenopcdc Slit (about 1 mm. in diam- 
 eter) may be used to discover the two principal meridians 
 (and the amount of astigmatism). It is placed in front of 
 one eye, the other being excluded, and is rotated slowly so 
 
 Fig. 315. — ^Astigmatic Dial. 
 
342 ERRORS OF REFRACTION 
 
 that the slit occupies each meridian successively. The pa- 
 tient is placed at 20 feet before the distant test types and the 
 position of the slit in which the best vision is obtained is 
 noted. Then convex or concave lenses are placed in front of 
 the slit, and the strongest convex or the weakest concave lens 
 which gives the most improvement is the measure of the re- 
 fraction in this meridian. The slit is then turned 90°, and 
 convex and concave lenses are again applied until one is found 
 which improves vision most. In this way the refractive error 
 of the two principal meridians is determined. If, for instance 
 when the slit is vertical the patient reads %, and convex lenses 
 in front of the slit make the types indistinct, the vertical me- 
 ridian is emmetropic; if, when the slit is horizontal, the patient 
 reads §, but this increases to § when -f- 3 D. Sph. is placed 
 in front, the horizontal meridian is hyperopic 3 D.; this case 
 would be one of simple hyperopic astigmatism corrected by a 
 4- 3 D. cylinder, axis vertical. 
 
 The Subjective Method with Test Types mid Test Lenses is 
 best employed after the objective tests have furnished us with 
 pretty definite conclusions regarding the correcting lenses. It 
 then serves to confirm or improve upon the results obtained by 
 objective methods: The lenses selected by the latter tests are 
 placed in the trial frame and may then require modification, 
 either in the strength of the sphere or the strength and axis 
 of the cylinder, so as to secure the most acute vision. 
 
 The Ophthalmoscope, Indirect Method. — ^The shape of the 
 disc is oval instead of circular, and changes when the objec- 
 tive lens is withdrawn. 
 
 The Ophthalmoscope, Direct Method. — ^Thedisc appears oval, 
 the elongation corresponding to the meridian of greatest 
 refraction. To determine the kind and amount of error we 
 estimate the refraction of a small vertical blood-vessel and 
 then of a small horizontal vessel near the disc, by means of 
 the strongest convex or the weakest concave lens with which 
 these are distinctly seen. For instance, suppose a vertical 
 vessel is seen clearly with + 2 D. Sph. (indicating hyperopia 
 of horizontal meridian), and a horizontal vessel with -f- 4 D. 
 (indicating a greater amount of hyperopia in the vertical 
 
TESTS FOR ASTIGMATISM 
 
 343 
 
 meridian); the case is one of compound hyperopic astigma- 
 tism. When the principal meridians are obhque, we find a 
 vessel the direction of which corresponds to one of the merid- 
 ians, and then another at right angles to the first, and estimate 
 the refraction of each. 
 
 Retinoscopy is the most rapid and reliable objective method 
 of determining astigmatism. The principal meridians are 
 clearly indicated by the edge of the shadow (Fig. 296). Each 
 of the principal meridians is corrected separately by causing 
 a reversal of the movement of the shadow by spherical lenses, 
 and adding —ID. (with plane mirror at 1 meter distance). 
 
 The Ophthalmometer (Fig. 316) is an instrument used for 
 determining the principal meridians and the amount of corneal 
 astigmatism. It is of service when used in connection with 
 other tests. It consists of a telescope containing a combina- 
 
 FlG. 316.— The Ophthalmometer. 
 
 tion of convex lenses and a bi-refracting prism, supporting a 
 graduated arc upon which are two sliding objects called 
 " mires " (Fig. 316). The latter are of white enamel, one 
 quadrilateral in shape, the other of similar size but cut out on 
 
344 
 
 ERRORS OF REFRACTION 
 
 
 
 one side into steps; both are divided in the middle by a hori- 
 zontal black line. The patient's face is placed in a frame at 
 the other end of the instrument and steadied by chin and fore- 
 head rests. The mires are reflected upon the cornea, and the 
 observer, looking through the tube and focussing, sees four 
 images in a line. The two peripheral images are ignored; the 
 two central ones are approximated until their inner edges 
 
 touch and the black lines subdi- 
 viding the mires form one con- 
 tinuous straight line; it may be 
 necessary to revolve the barrel 
 of the telescope more or less of 
 
 Fig. 317. Fig. 318. ^ro . j.i • ij. i rj. x 
 
 Fig. 317.-The Mires of the Ophthal- 45 tO the light Or left tO aC- 
 
 mometer Indicating an Absence of complish this. This pOsition, 
 
 Corneal Astigmatism. . i. j i i* i • xi. 
 
 PIG. 3i8.-The Overlapping of the indicated on a dial, gives the 
 Mires of the Ophthalmometer indi- meridian of least refraction. 
 
 eating 1 D. of Corneal Astigmatism, ivt x xi • j. j j. ■ i-x 
 
 Next the arc is turned at right 
 angles to this meridian. If the images of the mires are still in 
 apposition, the curvature of the cornea is uniform and there is 
 no corneal astigmatism (Fig. 317). If in the second meridian 
 the relative position of the images of the mires has changed, 
 each step which is overlapped by the quadrilateral figure in- 
 dicates 1 D. of astigmatism (Fig. 318). 
 
 Placido's Disc or Keratoscope (Fig. 6) consists of a circular 
 disc upon which are painted alternate rings of black and 
 white. The patient is placed 
 with his back to the light 
 and fixes the centre of the 
 disc, while the examiner 
 looks through an opening 
 in the centre and sees an 
 image of the concentric cir- 
 cles reflected upon the pa- 
 tient's cornea. If no astig- 
 matism is present the rings 
 are circular (Fig. 319). If regular astigmatism exists, the 
 rings will appear elliptical with the long axis corresponding 
 to the meridian of least curvature (Fig. 320). If the cor- 
 
 FlG. 319. Fig. 320. FiG. 321. 
 
 Fig. 319. — Corneal Reflection of Placido's 
 
 Disc in Emmetropia. 
 Fig. 320. — Corneal Reflection of Placido's 
 
 Disc in Regular Astigmatism. 
 Fig. 321. — Corneal Reflection of Placido's 
 
 Disc in Irregular Astigmatism. 
 
THE CORRECTION OF ASTIGMATISM 
 
 345 
 
 nea is the seat of irregular astigmatism the rings will be 
 distorted (Fig. 321). This forms a very useful test for ir- 
 regular astigmatism. 
 
 The Correction of Astigmatism. — ^Astigmatism is corrected 
 by cylinders, sphero-cylinders, and sometimes by crossed cyl- 
 inders (p. 306). The curve of the correcting^ cylinder corre- 
 sponds to the ametropic meridian; consequently its axis is at 
 right angles to this meridian. 
 
 Treatment consists in prescribing glasses which correct the 
 error. In some cases of high degree it is impossible to obtain 
 V. 20 even with full correction; we often have to be satisfied 
 with 30 or 40- But the vision often improves after the lenses 
 have been worn for a time. The glasses should be worn con- 
 stantly. When the correction has been estimated with the 
 eye under the effects of a cycloplegic, a slight reduction must 
 be made in cases of moderate or high degrees of astigmatism; 
 after a while, the full correction will be tolerated. The relief 
 which cylinders give is usually very pronounced. 
 
 The Direction of the Axis of a Cylinder is indicated accord- 
 ing to two systems: 
 
 RIGHT EYE " - LEFT EYE 
 
 Fig. 322. — Ordinary Method of Designating the Axis of Cylinders. 
 
 (1) By the angle which the axis makes with the horizontal, 
 this angle being numbered from 0° on our right (as we stand 
 before the patient) to 180° on our left (Fig. 322); i.e., 0° is 
 placed at the end of the horizontal meridian to the patient's 
 left, and the degrees are counted on the upper semicircle to 
 180° at his right (either eye). 
 
 (2) The position of the axis is denoted by the angular devi- 
 ation of the upper end of the cylinder from the vertical merid- 
 ian, either on the nasal or the temporal side. The vertical 
 
346 
 
 ERRORS OF REFRACTION 
 
 meridian is indicated by V, the horizontal meridian by H, the 
 angles on the temporal side by t, and those on the nasal side 
 
 TEMPORAL RIGHT EYE NASAL NASAL LEFT EYE TEMPORAL 
 
 Fig. 323. — ^Bisymmetrical Method of Designating the Axis of Cylinders. 
 
 by n. Thus, 30n=30° toward the nasal side; 604 = 60° to- 
 ward the temporal side, from the vertical meridian (Fig. 323). 
 Irregular Astigmatism is that variety in which there is not 
 only a difference of refraction in different meridians, but also 
 in different parts of the same meridian. It is generally due to 
 changes in the cornea, such as opacities and cicatrices follow- 
 ing ulceration, injuries, or surgical operations, and kerato- 
 conus. It may also result from partial dislocation of the lens, 
 or from a congenital or acquired change in the refractive 
 power of different sectors of the lens. The acuteness of vision 
 is considerably diminished and cannot be improved materially 
 by glasses. Details of the fundus when seen with the ophthal- 
 moscope appear distorted. An insignificant amount of irregu- 
 lar astigmatism is present normally, and accounts for our see- 
 ing the stars as stellate points instead of round dots. 
 
 ANISOKETBOPIA 
 
 This term is applied to cases of marked inequality in the 
 state of refraction of the two eyes; slight differences are pres- 
 ent in most cases of errors of refraction. Every combination 
 may occur: (1) One eye may be emmetropic and the other 
 ametropic; (2) both eyes may have the same variety of ame- 
 tropia, but of unequal degree; (3) one eye may be myopic and 
 the other hyperopic, either simple or combined with astigma- 
 tism. J Notwithstanding the unequal refraction, there is usu- 
 ally binocular vision; sometimes the eyes are used alternately; 
 in other cases one eye is habitually excluded from vision. 
 
ANISOMETROPIA 347 
 
 In prescribing glasses no arbitrary rules can be followed; 
 each case must be considered by itself. When one eye is em- 
 metropic and the other ametropic, no glass will probably be 
 required, unless it be to prevent the ametropic eye from suffer- 
 ing from disuse, or for the reUef of asthenopic symptoms. 
 When the difference in the refraction is not great (1 to 2 D.) 
 and there is good binocular vision, we may give each eye its 
 correction. Even when the difference is greater, correcting 
 lenses will often give satisfaction; but when full correction 
 causes discomfort we must be satisfied with a partial correc- 
 tion. When there is no binocular vision, we generally give 
 a correcting glass for the better eye; iri such cases, if the 
 poor eye still possesses vision, the patient should be advised 
 to exercise it daily with the aid of a suitable lens, the good 
 eye being excluded. 
 
 ASTHENOPIA 
 
 Asthenopia (Weak Sight or Eye Strain) is a convenient 
 term which embraces the group of symptoms dependent upon 
 fatigue of the ciliary muscle or of the extraocular muscles. 
 
 S3rmptoms. — The condition is of very frequent occiu'rence 
 and causes a great variety of symptoms. The most common 
 manifestations of asthenopia are: (1) Pain in or around the 
 eyes or headache, usually aggravated by use of the eyes for 
 close work, and in some cases present only after near use. 
 (2) Fatigue and discomfort upon use of the eyes for near; 
 this shows itself by inability to indulge in such work for more 
 than a short period at a time, without the occurrence of dim- 
 ness of vision and confusion of the lines of print, pain in and 
 about the eyes, headache, drowsiness, lacrymation, photopho- 
 bia and congestion, and an irritable condition of the lids ac- 
 companied by itching and burning sensations. These symp- 
 toms are regularly worse at night, when the patient is tired, 
 or when artificial illumination is employed. (3) Vertigo and 
 a tendency to diplopia. (4) Reflex symptoms, such as nausea, 
 twitching of the facial muscles, migraine, chorea, neurasthe- 
 nia, and possibly other neuroses. 
 
 The amount of asthenopia depends not only upon the kind 
 
348 ERRORS OF REFRACTION 
 
 and degree of defect, but also upon the state of the patient's 
 health, and is therefore pronounced in delicate, anaemic, and 
 neurasthenic individuals. 
 
 Varieties. — 1, Accommodative. 2, Muscular. 3, Neuras- 
 thenic. Two of these varieties may be associated. 
 
 Accommodative Asthenopia is the most common variety. 
 It is due to strain and fatigue of the ciliary muscle when used 
 too constantly or excessively, in ametropia. It is especially 
 frequent in astigmatism and hyperopia, but is common 
 enough in myopia and in presbyopia. Treatment consists 
 in the use of glasses correcting the error of refraction as ad- 
 vised in preceding pages. In delicate and neurasthenic indi- 
 viduals attention to the general health is very important. 
 
 Muscular Asthenopia is due to a want of balance of the 
 motor apparatus of the eye (heterophoria), necessitating an 
 abnormal strain to preserve single binocular vision. It may 
 be associated with ametropia and its existence be dependent 
 upon the latter error, or it may occur in emmetropia. Het- 
 erophoria is described in Chapter XXV. 
 
 Neurasthenic Asthenopia (Nervous, Hysterical, or Retinal 
 Asthenopia) is the variety which occurs in emmetropic pa- 
 tients, or in ametropes in whom proper correcting lenses and 
 treatment of any existing heterophoria give no relief. The 
 symptoms are ascribed to lack of nerve-tone; occasionally they 
 are supposed to be due to retinal anaesthesia or hyperaesthesia. 
 The condition is a neurosis and dependent upon a general 
 asthenic condition of the nervous system; consequently it is 
 found most frequently in young women with hysterical ten- 
 dency, who suffer from anaemia, neurasthenia, and often men- 
 strual disorders; also in neurasthenic individuals in general, 
 and in convalescents from debilitating diseases. It is often 
 very troublesome and obstinate. The more carefully one in- 
 vestigates the state of refraction and the motor balance of the 
 eye, the fewer cases one finds necessary to classify as neuras- 
 thenic. Treatment consists in removing the defect in the 
 general condition, rest of the eyes, and particularly atten- 
 tion to hygiene, such as the regulation of habits, outdoor 
 exercise, etc. 
 
HOMATROPINE AND ATROPINE 349 
 
 MYDRIATICS AND CYCLOPLEGICS 
 
 The action of these agents and the method of obtaining the 
 best results with them are described in Chapter XXVI. 
 
 A cycloplegic is indicated in the estimation of the refraction 
 in all cases of children and young adults, in many cases between 
 the ages of 40 and 45, and occasionally between 45 and 50 
 when the previous investigation of the refraction without pa- 
 ralysis of accommodation has been unsatisfactory. Before 
 using these agents in elderly persons, any suspicion of glau- 
 coma must be excluded. 
 
 Homatropine (2 per cent.), or homatropine, 2 per cent., 
 combined with cocaine, 1 per cent., is the agent most fre- 
 quently employed; one drop is instilled every 5 minutes for 
 4 doses, and the examination begun at the end of 50 minutes 
 after the last instillation. 
 
 Exceptionally, homatropine fails to produce complete pa- 
 ralysis of accommodation, as shown by more or less contradic- 
 tion in the results of the objective and subjective tests. In 
 such cases, particularly in children, we may resort to atropine 
 (1 per cent.), one drop being instilled 3 times daily for 2 or 3 
 days (smoked glasses may be worn during this period), and a 
 final drop directly before the examination. 
 
 In children and in young adults, it is proper to make one 
 examination without a mydriatic, a second under the influ- 
 ence of homatropine, and then to base the prescription for 
 glasses upon a comparison of these results, according to the 
 rules given in the preceding pages. 
 
 THE FITTING OF EYEGLASSES AND SPECTACLES 
 
 Much of the comfort and relief which lenses bring depend 
 upon the skill with which the glasses, are fitted to the face. 
 Whether eyeglasses or spectacles, the lenses must be sup- 
 ported in their frames in such a manner that the distance be- 
 tween their geometric centres corresponds to the interval 
 between the centres of the pupils {interpupillary distance). 
 
 If the glasses are to be worn constantly, the geometrical 
 centre of the lenses should be slightly below the centre of the 
 pupils, and the lenses tilted so that their surfaces form an 
 
350 ERRORS OF REFRACTION 
 
 angle of about 15° with the plane of the face. If worn for 
 distance only, the level of the lenses should be the same and 
 the tilting about 10°. If worn for near work only, the lenses 
 should be lower, and inclined about 25°. 
 
 In every case the glasses should be worn as near the eyes as 
 possible, just avoiding the lashes. 
 
 Lenses are usually made of crown glass. The periscopic 
 form of spherical lenses (p. 298) is preferred. In cylinders, 
 one surface may be plane and the other curved; but such 
 lenses can also be ground with two curved surfaces, the cylin- 
 der corresponding to the outer surface. Sphero-cylinders usu- 
 ally have the spherical lens on one surface and the cylindrical 
 lens on the other. In toric lenses both the cylindrical and 
 spherical curves are ground on the outer surface, the irmer 
 being deeply concave; this gives an enlarged field and re- 
 duces the weight and thickness of the lens. Lenses cut from 
 crystal are known as pebbles; they have the advantage of 
 being less easily scratched. 
 
 In cases of astigmatism, it is necessary that the axis of the 
 cylinder be constant. On this account spectacles are often pre- 
 ferred to eyeglasses, because with the latter the axis of the 
 
 Fig. 324. — ^Bifocal Lens (Oval Paster). Fie.325. — ^Bifocal Lens (Circular Paster). 
 
 cylinder may vary according to how the glasses are worn or 
 how they preserve their original adjustment. But eyeglasses 
 can be worn in such cases, if the optician exercises sufficient 
 skill in fitting and the patient has the glasses readjusted from 
 time to time. 
 
 Bifocal Lenses consist of an upper portion of one focus, and 
 a lower part of another. They are used principally in cases 
 
BIFOCAL LENSES 
 
 351 
 
 of presbyopia associated with ametropia, the lower portion 
 being used for reading and near work, and the upper for dis- 
 tance. The bifocal lenses most often used are those in which 
 the addition consists of an oval or 
 circular segment cemented to the 
 lower portion of one surface of the 
 distance glass (Figs. 324 and 325). 
 The invisible bifocal lens is construc- 
 ted of two blades of crown glass, be- 
 tween which the presbyopic segment 
 is inserted before they are cemented 
 together (Fig. 326), or of one lens 
 upon which the reading portion 
 is fused (fused bifocal); the in- 
 creased strength of the smaller 
 
 lens depends upon the higher refractive index of flint glass 
 of which it is made; a third form has both the distance and 
 the near correction groimd on a single piece of crown glass 
 in toric form (one-piece bifocal). These invisible bifocal 
 lenses are very neat and are achromatic, but expensive. 
 
 COUNTERSUNK BLADE. 
 
 COMPLETED LENS. 
 
 Fig. 326.— Section of the Invis- 
 ible Bifocal Lens. 
 
CHAPTER XXIV 
 
 ANOMALIES OF ACCOMMODATION 
 
 Under this heading are included presbyopia, paralysis 
 of accommodation, and spasm of accommodation. 
 
 PRESBYOPIA 
 
 Presbyopia (old sight, Pr.) is a physiological change which 
 affects every eye, commencing between the 40th and i5th 
 years, as a result of which the near point recedes beyond the 
 distance at which we read ordinary print; this distance has 
 been fixed somewhat arbitrarily at 22 cm. (about 9 inches). 
 The change is due chiefly to loss of elasticity of the lens, pre- 
 venting a response to the action of the ciliary muscle; conse- 
 quently the power of accommodation is lessened. As explained 
 on page 312, this diminution in the power of accommodation 
 begins early, about the 10th year. Between the 40th and 45th 
 years it becomes sufficient to interfere with the comfortable 
 exercise of near vision; then presbyopia is said to be present. 
 
 At the age of 40, there are 4.5 D. of accommodation, and 
 the near point is at 22 cm., or 9 inches. To read at 9 inches, 
 such an individual would require all of his accommodation 
 and the effort would soon become fatiguing, since only one- 
 half or two-thirds of this power can be used for any length of 
 time without causing asthenopia. Generally, however, the 
 adult holds print at about 13 inches (33 cm.), requiring 3 D. 
 of accommodation and leaving a reserve of 1.50 D., usually 
 sufficient for comfort. At 45 his accommodation has dimin- 
 ished to 3.5 D.; all or nearly all of this would be required to 
 read comfortably at 13 inches, leaving little or no reserve. If 
 he keeps one-third of his accommodation in reserve, he will 
 have about 2.25 D. available for near work; with this, his 
 reading distance would be 45 cm., or 18 inches — too great for 
 comfortable and continuous near work. Hence we must sup- 
 
 352 
 
PRESBYOPIA 353 
 
 ply the defect in accommodation by a convex lens sufficient to 
 bring the near point to a convenient distance. 
 
 Symptoms. — The presbyope is compelled to hold reading, 
 sewing, and other forms of near work farther away than the 
 usual distance, making such efforts uncomfortable. With re- 
 cession of the near point beyond the usual situation, the print 
 becomes -pale and indistinct, and fine tj^e can be read only 
 with great difficulty. The patient is apt to use strong illumi- 
 nation; this produces contraction of the pupil, and thus im- 
 proves the definition by diminishing the circles of diffusion. 
 If the condition be uncorrected, he suffers from asthenopic 
 symptoms, especially pain, fatigue, lacrymation, dimness of 
 vision, and irritation of the lids, all of these symptoms being 
 more marked with poor light or at night with artificial illumi- 
 nation. Presbyopia has no effect upon distant vision. 
 
 Treatment consists in prescribing convex spherical lenses for 
 near work so as to compensate for the lack of power of accom- 
 modation, and to bring the near point back to a comfortable 
 working distance, about 13 inches. 
 
 We can generally prescribe the correcting glasses according 
 to age. The rule is to give -|- 1 D. at 45, and to add 1 D. 
 for every five years; this will bring the near point back to 22 
 cm., or 9 inches: 
 
 Age 45, glass required + 1 D. 
 
 " 50, " " +2D. 
 
 " 65, " " +3D. 
 
 " 60, " " +4D. 
 
 " 65 and over " +4.50D. 
 
 The numbers just given are somewhat arbitrary; frequently 
 we will find that a slightly weaker lens will be sufficient. The 
 age at which patients are obliged to wear glasses varies within 
 a few years, and is influenced, to a certain extent, by the vigor 
 of the individual; a delicate or neurasthenic person will re- 
 quire glasses for reading earlier than a robust individual. 
 
 The glasses must also be selected with reference to the occu- 
 pation or the special iwe for which the patient wishes them. 
 Thus in reading, writing, and sewing, 13 inches (33 cm.) is 
 a comfortable working distance for most persons; but a musi- 
 
354 ANOMALIES OF ACCOMMODATION 
 
 cian may prefer a distance of 20 inches (50 cm.), and conse- 
 quently he will require a weaker glass. 
 
 To find the glass required, we note the patient's near point; 
 then we estimate the lens which represents this point; finally 
 we subtract this number from the lens whose focus corre- 
 sponds to the distance at which the patient desires to work. 
 For example, suppose the near point has receded to 50 cm. 
 (20 inches); this is represented by a + 2 D. lens (50 orjg 
 = 2). We wish to bring the near point to 33 cm. (13 
 inches), which corresponds to -|- 3 D. (^ or 53 = 3). 
 Hence + 2 D. from + 3 D. = + 1 D., the glass required. 
 
 The existence of ametropia will modify the strength of 
 glasses required for presbyopia. Hence the patient's vision 
 for distance, and the state of his refraction, must be deter- 
 mined before estimating the glasses required for near work. 
 In any case of ametropia the lenses required for distance must 
 be added to those which would be selected for presbyopia in 
 the emmetrope. This would have the effect of increasing the 
 strength of the convex lens required for presbyopia in cases of 
 hyperopia, and of diminishing its power in myopia. For ex- 
 ample, suppose a patient of 50 has hyperopia of 1.50 D.; his 
 glasses for reading would be H. 1.50+Pr. 2 D. = + 3.50 D. 
 A myope of 2 D. will require no glass at 50, since — 2D. 
 and + 2 D. (Pr.) neutralize each other. At 55, he would re- 
 quire + 1 D. instead of the usual -)- 3 D. (- 2 D. + 3 D. = 
 + 1 D.). If the myopia amounts to 5.00 D., the patient will 
 never require glasses for reading, since his far point will 
 always be 20 cm., or 8 inches. In astigmatism, the cylinders 
 must be added to the convex lenses required for the correction 
 of presbyopia. 
 
 Since presbyopia increases with age, glasses will require 
 changing for stronger ones every few years. When glasses have 
 to be changed for stronger lenses very frequently, we suspect 
 glaucoma and examine the eye carefully for this disease. 
 
 PARALYSIS OF ACCOMMODATION 
 
 Paralysis of Accommodation (Cycloplegia) is a partial (par- 
 esis) or complete (paralysis) loss of power in the ciliary muscle 
 
PARALYSIS OF ACCOMMODATION 355 
 
 due to paralysis of the third nerve, or of that branch of the 
 motor ocuH which supplies the ciliary muscle and iris. 
 Though occasionally confined to the ciliary muscle, the pa- 
 ralysis usually includes the sphincter pupillae. When limited 
 to the cihary muscle and iris, it is known as ophthalmoplegia 
 interna (p. 369). 
 
 Etiology. — The most frequent cause is the use of mydriatics. 
 It may be part of a complete paralysis of the third nerve. It 
 occurs not infrequently after diphtheria. Other causes are 
 contusions of the eyeball, debilitated states of the system, 
 grippe, sjrphilis, diabetes, and cerebral disease. 
 
 Symptoms. — These are toss of power of accommodation and 
 dilatation of the pupil. If emmetropic, the patient will have 
 good vision for distance, but will be unable to do near work 
 without convex glasses. If hyperopic, both near and distant 
 vision will be impaired. If myopic, the patient will be able 
 to see only at his far point; he may therefore be able to do 
 without his accommodation, if the myopia is considerable. 
 
 Prognosis is usually good, especially when the affection is 
 due to syphilis or diphtheria. In traumatic cases the con- 
 dition may be permanent. 
 
 Treatment. — ^We attempt to remove the cause: In syphilis, 
 specific treatment is indicated. In post-diphtheritic paralysis, 
 and in that due to debilitated conditions, tonics are given, 
 especially strychnine. Locally, the miotics (eserine or pilo- 
 carpine) are employed. These cause contraction of the pupil 
 and of the ciliary muscle, producing spasm of accommoda- 
 tion, and temporarily relieve the symptoms; the alternate 
 contraction and relaxation of the ciliary muscle often stimu- 
 late it to action. The local application of electricity is some- 
 times useful. In traumatic cases, complete rest is indicated, in 
 addition to the remedies just mentioned. If the paralysis has 
 lasted some time, convex glasses may be given for near work. 
 
 SPASM OF ACCOMMODATION 
 
 Tonic spasm of the ciliary muscle is frequently met with in 
 children and in young adults; it occurs generally in hyperopia, 
 but it may accompany E. or any error of refraction. 
 
356 ANOMALIES OF ACCOMMODATION 
 
 Etiology. — It is usually due to long-continued application of 
 the eyes for near work, especially when the young patient is 
 in poor health, has uncorrected ametropia, and the work has 
 been excessive and done with poor illumination. 
 
 Symptoms. — Both eyes are usually affected. There are as- 
 thenopia and diminished acuteness of vision. In emmetropia, 
 the spasm gives rise to the signs of myopia; in hyperopia, it 
 reduces the amount of manifest error and increases the pro- 
 portion of latent hyperopia, or it may even cause the patient 
 to appear myopic; in myopia the error is increased. The 
 diagnosis is made after instilling a cycloplegic; in some of 
 these cases homatropine is insufficient and atropine must be 
 used. 
 
 Treatment consists in the abstinence from near work, the 
 correction of ametropia, attention to the general health, and the 
 production of paralysis of accommodation for a few days or 
 weeks by instillations of atropine. 
 
CHAPTER XXV 
 
 DISTURBANCES OF MOTILITY OF THE EYE 
 
 Anatomy and Pfiysiology. — The eyeball is moved by six muscles, the 
 extrinsic musdes, consisting of the four straight and the two oblique; 
 these arise from the wall of the orbit and are inserted into the sclera. 
 
 The Recti {interfial, external, superior, inferior) arise from the circum- 
 ference of the optic foramen at the apex of the orbit, run forward sur- 
 rounding the optic nerve and posterior portion of the eyeball, and are 
 inserted into the sclera by means of flattened tendons about 10 mm. 
 wide. The lines of insertion of these muscles are not equidistant from 
 the cornea, but have somewhat the form of a spiral; that of the internal 
 rectus is 5 mm., of the inferior rectus 6 mm., of the external rectus 7 
 mm., and of the superior rectus 8 mm., from the cornea. 
 
 The Superior Oblique arises from the border of the optic foramen, runs 
 forward to the upper and inner angle of the orbit, at the anterior extrem- 
 ity of which it passes through a fibrous pulley; it then continues outward, 
 passing beneath the superior rectus, and is inserted into the upper part 
 of the sclera behind the equator. The Inferior Oblique arises from the 
 superior maxillary bone at the inner portion of the lower border of the 
 orbit, passes outward below the inferior rectus, and is inserted into the 
 outer part of the sclera behind the equator. 
 
 The muscles are ensheathed by the fascia of the orbit. Tenon's capsule, 
 which also covers the sclera and sends prolongations to the walls of the 
 orbit which serve to fix the eyeball in its place. These prolongations 
 are most prominent upon the internal and external recti muscles; they 
 serve to restrain the excursions of the eyeball and are known as "check 
 ligaments." 
 
 I Nerve Supply. — The third nerve (oculomotor) supplies all the muscles 
 except the external rectus, innervated by the sixth (abducens), and the 
 superior oblique, which is supplied by the fourth (trochlearis) . The nuclei 
 for these three nerves are found in the floor of the fourth ventricle. 
 
 Action of the Muscles. — The six extrinsic muscles serve to 
 rotate the eyeball around a vertical, transverse, and antero-pos- 
 terior axis, the centre of rotation corresponding approximately 
 to the centre of the eyeball, and the movements being free in 
 all directions, like a ball-and-socket joint. The movements 
 which take place about the vertical axis are adduction (toward 
 the nose) and abduction (toward the temple); about thetrans- 
 
 357 
 
358 DISTURBANCES OF MOTILITY OF THE EYE 
 
 verse axis, elevation and depression; and about the antero- 
 posterior axis, wheel rotation or torsion, causing the upper end 
 of the vertical meridian to be incHned inward or outward. 
 
 The External Rectus moves the eyeball outward. 
 
 The Internal Rectus moves the eyeball inward. 
 
 The Superior Rectus moves the eyeball upward, inward, and turns the 
 upper extremity of the vertical meridian inward. 
 
 The Inferior Rectus moves the eyeball downward, inward, and turns 
 the upper end of the vertical meridian outward. 
 
 The Superior Oblique rotates the upper end of the vertical meridian 
 inward, and moves the eyeball downward and outward. 
 
 The Inferior Oblique rotates the upper end of the vertical meridian 
 outward, and moves the eyeball upward and outward. 
 
 Movements of the Eyeball. — In every movement of the 
 eyeball several muscles act at the same, time, as follows: 
 
 Adduction: 
 
 Internal Rectus. 
 
 Superior Rectus. Abduction: 
 
 Inferior Rectus. 
 
 External Rectus. 
 Superior Oblique. 
 Inferior ObUque. 
 
 „, ,. J Superior Rectus. _ . /Inferior Rectus. 
 
 Elevaiion: t / ■ /^..v Depression: \„ . „, ,. 
 
 I Inferior Obuque. I Superior Obuque. 
 
 Rotation of upper extremity of 
 vertical meridian inward. 
 
 Rotation of upper extremity of 
 vertical meridian outward. 
 
 Superior Oblique. 
 Superior Rectus. 
 Inferior Oblique. 
 Inferior Rectus. 
 
 Both eyes always move simultaneously {associated move- 
 ments), regulated by centres of association which innervate 
 certain muscles or groups of muscles of the two eyes simul- 
 taneously. The associate or conjugate movements occur 
 either in the same direction, with the visual lines parallel, or 
 with the lines inclined toward each other (convergence). 
 
 The Field of Fixation corresponds to thelimits of movement 
 of the eyeball in differeni^diredions, without moving the head. 
 It is best estimated by the perimeter (Fig. 19) . The patient's 
 head is fixed so that the eye under examination is opposite the 
 centre of the instrument, and the other eye covered. A short 
 word printed with small test-letters is moved along the arc of 
 the perimeter, from the .periphery to the centre, until the 
 patient can name the word, using the eye alone and not mov- 
 ing the head. The field of fixation in the normal eye is about 
 45° upward, inward, and outward, and about 60° downward. 
 
THE FIELD OF FIXATION 359 
 
 A special instrument (Stevens' Tropometer) may be used for 
 the determination of the rotations of the eyes. 
 
 Binocular Vision and Diplopia. — ^Under ordinary condi- 
 tions, both eyes are concerned in the act of vision, and are in- 
 voluntarily adjusted, so that the image of an object is focussed 
 on the macula of each eye. The two images are then fused 
 into a single mental perception. This faculty constitutes bin- 
 ocular single vision, and is controlled by the sense oi fusion, the 
 origin of the impulse being the fusion centre of the brain. 
 
 When images fall on symmetrical points of the two retinse, 
 a single visual sensation is produced (binocular single vision). 
 When the visual lines of the two eyes are not directed toward 
 the same object, i.e., when one eye deviates, diplopia or 
 double images result, unless the image of the deviating eye is 
 suppressed. The diplopia is proportional to the amount of 
 deviation. The image which corresponds to the eye which 
 " fixes " the object is distinct, because it lies at the macula, 
 and is known as the true image; the image of the deviating eye 
 is less distinct, because it is perceived by a peripheral part of 
 the retina, and is known as the false image. 
 
 Objects situated to the right of the point of fixation throw 
 their images to the left of the macula; those placed to the left 
 of the point of fixation form images to the right of the macula. 
 In the same manner objects above or below the point of fixa- 
 tion cast their images below or above the macula respectively. 
 By reversing this process we judge of the situation of an ob- 
 ject, and place it at the extremity of an imaginary line drawn 
 from the retinal image through the nodal point; this process is 
 known as projection, and is learned by experience. It enables 
 us to judge of the relative positions of objects; an object which 
 forms its image to the right of the macula is situated to our 
 left; one which throws its image below the macula is situated 
 above, etc. 
 
 If an eye is deflected, an object situated straight ahead will 
 form its image on either side of the macula, and following out 
 this process of projection, it will be referred to the opposite 
 side of the outside world. 
 
 Diplopia is said to be homonymous when the false image is 
 
360 DISTURBANCES OF MOTILITY OF THE EYE 
 
 on the same side as the deviating eye, and crossed when it is 
 on the opposite side. When the two images are level, the 
 diplopia is known as horizontal; when displaced vertically, the 
 diplopia is called vertical. 
 
 In Fig. 327, the right eye is turned in, and diplopia results. 
 The patient sees a true image with the left eye, forming at the 
 
 
 At, 
 
 UFI 
 
 \ 
 
 A 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 (^ 
 
 V \ 
 "-v \ 
 
 X^^>'ni 
 
 s-^ 
 
 
 
 LEFT 
 
 
 RIGHT 
 
 Fig. 327. — Deviation of the Right Eye In- 
 ward. Homonymous Diplopia. T/, True 
 Image; FI, False Image; m. Macula. 
 
 Fig. 328. — Deviation of the Right Eye 
 Outward. Crossed Diplopia, r/. True 
 Image; FI, False Image; m. Macula. 
 
 macula and referred to its proper place, TI. In the right eye, 
 on account of the deviation inward, the image is thrown upon 
 the retina to the left of the macula and consequently is pro- 
 jected to the right, at FI. The image of the right eye being 
 to the right of the image of the left eye, the case is one of 
 homonymous double images. 
 
 In Fig. 328, the right eye turns out and diplopia results. 
 The image of the candle lies on the macula in the left eye and 
 is referred to its correct position; a true image is seen at TI. 
 In the right eye, because of its outward deviation, the image 
 falls to the right of the macula and is consequently projected 
 to the left, at FI. The images having crossed in their relative 
 positions, that of the right eye being seen to the left of the 
 image of the left eye, the case is one of crossed diplopia. 
 
 Double images may also be produced without any devia- 
 tion by placing a prism in front of the eyes. The prism will 
 deflect the rays so that instead of falling upon the macula, 
 they reach the retina to one side of it. 
 
 Varieties of Ocular Deviations. — Deviations from perfect 
 muscular adjustment comprise: 
 
VARIETIES OF OCULAR DEVIATIONS 361 
 
 1. Paralysis, a deviation in the visual axes due to actual 
 loss of motion in one or more of the ocular muscles; it may be 
 (1) complete or (2) partial {pa/resis). 
 
 2. Strabismus (Squint or Heterotropia), a decided manifest 
 deviation due to absence of binocular fixation, which it is im- 
 possible for the patient to overcome. 
 
 3. Heterophoria (Insufficiency), a tendency to slight devia- 
 tion, which is latent, due to the absence of binocular equilib- 
 rium, and habitually corrected by muscular effort prompted 
 by the desire for binocular vision. 
 
 The eyes are properly balanced, or in a state of equilibrium, 
 when the visual lines meet at the object toward which they 
 are directed. This condition is brought about by harmoni- 
 ously distributed iimervation of the muscles; it is known as 
 orthophoria. . Any disturbance of this muscular equilibrium 
 causes a lack of balance or an "imbalance." In speaking of 
 errors of this sort, we always take both eyes into consideration. 
 
 In heterophoria, one eye deviates under cover; but when 
 both eyes are used, the desire for single vision prompts a con- 
 veyance of increased innervation to the defective muscles, and 
 this causes the visual lines to meet exactly at the object to 
 which they are directed.- The eyes are then placed in a con- 
 dition of forced equilibrium by the expenditure of an amount 
 of nervous force which frequently causes symptoms of mus- 
 cular asthenopia. Ordinarily, therefore, the deviation is not 
 apparent; hence it is called latent deviation. 
 
 In squint, the deviation cannot be overcome by increased 
 innervation; the error is manifest. There is a distinct differ- 
 ence between squint and heterophoria; occasionally the latter 
 may change to temporary or permanent squint. 
 
 Both of these conditions are differentiated from paralysis 
 by the fact that in the latter affection there is complete or 
 partial loss of power in one or more of the muscles. 
 
 FABALT8IS OF THE OCtTLAE. MUSCLES 
 Symptoms. — 1. Limitation of Movement of the eye on the 
 side and in the direction of action of the paralyzed muscle; 
 this is pronounced in complete paralysis and less marked in 
 
362 DISTURBANCES OF MOTILITY OF THE EYE 
 
 paresis. It can generally be recognized when the patient 
 keeps his head fixed and tries to follow the examiner's finger 
 moved in different directions. If merely a paresis, the defec- 
 tive movement may be so limited that the diagnosis must be 
 made from the nature of the diplopia. 
 
 2. Paralytic Squint. — When the eyes are turned in the di- 
 rection of the sphere of action of the paralyzed muscle, the 
 sound eye will be directed properly, but the affected eye will 
 refuse to move, and will squint. The deviation is generally 
 apparent, but more marked the farther the eyes are moved in 
 the direction of the paralyzed muscle. When the eyes are 
 turned in the opposite direction, in which the paralyzed 
 muscle need not participate, there is no squint. 
 
 The deflection of the squinting eye is known as the primary 
 deviation; it is always in the direction opposite to the normal 
 action of the paralyzed muscle. If the affected eye be made 
 to fix an object and the sound eye be covered, the latter will 
 squint in a corresponding direction, and much more than the 
 affected eye; this deflection of the sound eye is known as the 
 secondary deviation. The excess of secondary deviation over 
 the primary is due to the fact that the strong impulse of inner- 
 vation required to enable the paralyzed eye to fix, being si- 
 multaneously transmitted to the associated muscle of the sound 
 eye, produces an overaction of this muscle, and consequently 
 a greater amount of squint. This is an important point in 
 distinguishing between paralytic and concomitant squint; in 
 the latter, the primary and secondary deviations are equal. 
 
 3. Oblique Position of the Head. — The patient turns his 
 head toward the side of the paralyzed muscle and in the direc- 
 tion in which the paralyzed muscle would, if acting, move the 
 eye. This is done so as to diminish or correct the diplopia. 
 Hence there is a characteristic position of the head for every 
 variety of paralysis. 
 
 4. False Projection. — The paralyzed eye does not see ob- 
 jects in their correct location. The false projection is due to 
 markedly increased innervation, conveyed to the nerve sup- 
 plying the paralyzed muscle in an effort to force it to act; this 
 gives the patient anerroneous idea of the position of the eye. 
 
PARALYSIS OF THE OCULAR MUSCLES 363 
 
 It can be demonstrated by closing the patient's sound eye and 
 telling him to point quickly at an object in front of him; the 
 finger will be directed to the side of the object corresponding 
 to the paralyzed muscle. 
 
 5. Diplopia occurs when looking at an object situated 
 within the sphere of action of the paralyzed muscle, and increases 
 when the eyes are moved toward this side. The presence or 
 absence of diplopia, the relative position of the double images, 
 and the increase or diminution of the distance between them 
 in different parts of the field of fixation, form the most im- 
 portant means of diagnosing the seat of paralysis. 
 
 6. Vertigo, nausea, and uncertain gait are frequent symp- 
 toms due to the diplopia and the false projection; they are 
 relieved upon closing the paralyzed eye. On this account, 
 patients frequently keep the affected eye covered. 
 
 Method of Testing for Diplopia: For convenience of record 
 and study a diagram is used, consisting of two horizontal and 
 two vertical lines, forming nine spaces (Figs. 329 to 334). The 
 patient must keep his head fixed and merely move his eyes. 
 A red glass is placed before one eye so as to distinguish its 
 image. A lighted candle held about 10 feet in front of the 
 patient is moved into different positions of the field of fixa- 
 tion, and the nature of the diplopia noted in each of the nine 
 spaces. The data required are: (1) in which position of the 
 field there is single vision and in which diplopia; (2) whether 
 the diplopia is homonymous or crossed; (3) the relative distance 
 between the double images; (4) whether the two images are on 
 the same or on different levels; and (5) whether the images are 
 erect or inclined. 
 
 The false image is situated in the direction of the normal 
 action of the paralyzed muscle, and the distance between the 
 double images increases in this direction, and diminishes in 
 the opposite direction. In fact, most of the symptoms — the 
 limitation of movement, the false image, the turning of the 
 face and oblique position of the head, the faulty projection, 
 and the increase in the distance between the double images — ■ 
 are in the direction of the normal action of the paralyzed muscle. 
 The squint, absence of diplopia, and diminution in the dis- 
 
3G4 
 
 DISTURBANCES OF MOTILITY OF THE EYE 
 
 tancc lictwccn the two images, are the onlj^ sjanptoms occur- 
 ring in the opposite direction. 
 
 After paralj'sis has hxsted a long time, tlie symptoms be- 
 come less characteristic. Diplopia disappears because the 
 image of the deviated eye is suppressed and faulty projection 
 is corrected by newly acquired experience; contracture of the 
 antagonist of the affected muscle increases the squint. 
 
 When one muscle only is paralj^zed, the diagnosis is easy ; 
 but when several muscles are involved, it is often difficult to 
 determine the exact combination. 
 
 Varieties of Ocular Paralysis. — One muscle may be in- 
 volved, or several muscles in various comt)inations may be 
 affected. Paralysis of the external rectus is the most com- 
 mon; that of the superior oblique is frequent; isolated paraly- 
 sis of the remaining four muscles is much less common. 
 Combined paralysis of some or all of the four muscles sup- 
 plied by the third nerve is exceedingly common. 
 
 Xxfl ' 
 
 L R 
 
 LR 
 
 : :fl 
 
 ■ Q" : 
 
 L.R 
 
 L R 
 
 L R 
 
 (id , 
 
 LR 
 
 r 
 
 (1 
 
 LR 
 
 L R 
 
 £L 
 
 L R 
 
 ■Vfl; 
 
 ■. kr 
 
 ■ fl 
 
 L R 
 
 n 
 
 LEFT EYE RIGHT EYE 
 
 Fig. 329. — Paralysis of the External Rectus (the dotted outline refers to the false image)'. 
 
 Paralyds of the External Rectus {Sixth Nerve). — There is limitation 
 of movement outward; eonvergent sqtiint; and the face is tiu-ncd toward 
 the paralyzed side. Homonymous diplopia upon looking toward the 
 paralyzed side; the images are on the same level and parallel (slightly 
 tilted in the upper or lower portions of the field); the lateral separation 
 increases with abduction of the paralyzed eye (Fig. 329). 
 
 Paralysis of tlie Internal Rectus. — There is limitation of movement 
 inward; divergent squint; the face is turned toward the sound side. 
 Crossed diplopia on looking toward the sound side; images are on a, 
 level and parallel (slight ly tilted in u|)i)er and lower parts of field) ; lateral 
 separation increases with adduction of the paralyzed eye (Fig. 330). 
 
PARALYSIS OF THE OCULAR MUSCLES 
 
 365 
 
 Paralysis of the Superior Rectus. — There is limitation of movement 
 upward and toward the sound side; deviation of the eye downward and 
 a httle outward, with the vertical meridian inclined toward the temple; 
 the face is directed upward and toward the sound side, and the head 
 
 L 
 
 
 R 
 
 L 
 
 
 U 
 
 : J;' 
 
 fill 
 
 R L 
 
 R- 
 
 ,5 
 
 R L 
 
 'S- : 
 
 f:ir 
 
 RL 
 
 R L 
 
 R L 
 
 RL 
 
 ■::o'.' 
 
 'iA 
 
 JO 
 
 R L 
 
 R L 
 
 R i: 
 
 RL: 
 
 ;i"'; 
 
 LEFT EYE 
 
 RIGHT EYE 
 
 Fig. 330. — Paralysis of the Internal Rectus (the dotted outline refers to the false image). 
 
 inclined toward the shoulder of the healthy side. Crossed and vertical 
 diplopia upon looking up; the false image is higher and its upper end 
 inclined toward the nose; the vertical distance between the images in- 
 
 R 
 
 S^ 
 
 0/?' \\.fl 
 
 Rl ^l 
 
 •^L 
 
 h 
 
 L 
 
 ffl' 
 
 t: 
 
 0;. -9;.: 
 
 0"^^ 
 
 1^ 
 
 ;•;■&■' 
 
 ,,,fi-::' 
 
 r^' [J' 
 
 fl 
 
 : Q, 
 
 LEFT EYE RIGHT EYE 
 
 Fig. 331. — Paralysis of the Superior Rectus (the dotted outline refers to the false image). 
 
 creases, and the inchnation of the false image diminishes, upon looking 
 upward and toward the paralyzed side (Fig. 331). 
 
 Paralysis of the Inferior Rectus. — There is limitation of movement 
 downward and toward the sound side; deviation of the eye upward 
 and slightly outward, with the vertical meridian inchned toward the 
 nose; the face is directed downward and toward the sound side, and 
 inclined toward the shoulder of the paralyzed side. Crossed and ver- 
 tical diplopia on looking down; the false image is lower, and its upper 
 end inclined toward the temple; the vertical distance between the 
 
366 
 
 DISTURBANCES OF MOTILITY OF THE EYE 
 
 images increases, and the inclination of the false image decreases, upon 
 looking downward and toward the paralyzed side (Fig. 332). 
 
 Paralysis of the Superior Oblique (Fourth Neriie). — There is Umitation 
 
 
 ' fl 
 
 ■ fl 
 
 ;o 
 
 _,u 
 
 J - 
 
 ^.Q... 
 
 R U 
 
 i^ 
 
 J 
 
 LEFT EYE RIGHT EYE 
 
 Fig. 332. — Paralysis of the Inferior Rectus (the dotted outline refers to the false image). 
 
 of movement downward and toward the paralyzed side; the eye is de- 
 viated upward and slightly inward, with the vertical meridian inclined 
 toward the temple ; the face is directed downward and toward the sound 
 
 1- ri» iil I So Do t 
 
 L- R *-" B "^ *- " 
 
 LR ^^ Jj^J^: ^^ ^^ 
 
 LEFT EYE RIQHT EYE 
 
 Fig. 333. — Paralysis of the Superior Oblique (the dotted outline refers to the false image) . 
 
 side, and the head is inclined over the shoulder of the sound side. The 
 patient has great difficulty in moving about, especially in going down- 
 stairs. Homonymous and vertical diplopia on looking down; the false 
 image is lower and its upper end inclined toward the sound side; the 
 vertical distance between the images increases, and the inclination of 
 the false image de(;reases, upon looking downward and toward the sound 
 side (Fig. 333). 
 
 Paralysis of the Inferior Oblique. — There is limitation of movement 
 upward and toward the paralyzed side; the eye is deviated downward 
 
PARALYSIS OF THE OCULAR MUSCLES 
 
 367 
 
 and slightly inward, with the vertical meridian inclined toward the 
 nose; the face is directed upward and toward the paralyzed side, and 
 the head is inchned toward the affected side. Homonymous and verti- 
 
 C.0 L.Q -'Q g^^R ^f. ^. 
 
 R R R L L L 
 
 a ■ J 1 
 
 LEFT EYE RIQHT EYE 
 
 Fig. 334. — Paralysis of the Inferior Oblique (the dotted outline refers to the false image) . 
 
 cal diplopia on looking up; the false image is higher and its upper end 
 inclined toward the temple; the vertical distance between the images 
 increases, and the inclination of the false image decreases, upon loolcing 
 upward and toward the sound side (Fig. 334). 
 
 The Diagnosis of the Particular Muscle or Muscles Para- 
 lyzed in any case in which we analyze the diplopia is often 
 
 Left 
 Sup.Rect 
 
 Left 
 Inf.Rect 
 
 .A 
 
 n 
 
 V 
 
 Right 
 Sup.Rect 
 
 Right 
 NF. Rect 
 
 Fig. 335. — Werner's Diagram showing the 
 Nature of the Diplopia in Paralysis of the 
 Superior and Inferior Recti Muscles. 
 
 Left V 
 InfObl. \ 
 
 \ 
 
 V 
 
 / 
 
 Left / 
 Sup.Obl ••* 
 
 / Right 
 / Inf.Obl. 
 
 \ 
 
 \ 
 
 •,^ Right 
 
 \Sup.Obl 
 
 Fig. 336. — Werner's Diagram showing 
 Nature of Diplopia in Paralysis of Su- 
 perior and Inferior Oblique Muscles. 
 
 difficult, on account of the different actions of the orbital mus- 
 cles. Werner's diagrams (Figs. 335 and 336) will serve as a 
 mnemonic aid in this respect: 
 
 "The form of diplopia which characterizes paralysis of each muscle 
 is expressed by the position of the dotted Hne bearing the name of the 
 
368 DISTURBANCES OF MOTILITY OF THE EYE 
 
 muscle. The dotted lines represent the false images, the continuous 
 lines the true images. 
 
 " In the case of the recti (Fig. 335) the false images enclose a lozenge- 
 shaped space situated between the true ones, whereas in the case of the 
 obMque muscles (Fig. 336) the true images, which for the sake of sim- 
 pHcity are combined in one line, he between the four false images, which 
 diverge from one another so as to form an X. It wiU also be noted that 
 the dotted hues extend upward and downward beyond the others, indi- 
 cating respectively that the false images are higher or lower than the 
 true ones. Another fact which the diagrams indicate is that in the case 
 of the muscles represented in the upper halves of the figures, the diplopia 
 occurs in the upper part of the field of fixation, or, in other words, in 
 upward movements of the eyes. A similar rule holds good with regard 
 to the lower halves. 
 
 ' ' The method of using the diagrams will be better understood by taking 
 a particular muscle as an example. Suppose, for instance, that we wish 
 to know what kind of diplopia results from paralysis of the left inferior 
 rectus, it is simply necessary to look at the left inferior portion of Fig. 
 335 (recti), which gives the diplopia. If we analyze this, we find: 1. 
 That the diplopia is crossed, for the false image corresponding to the 
 left eye is on the right of the true image — i.e., the right image corre- 
 sponds to the left eye. 2. That the false image has its upper end 
 inclined toward the true one. 3. That the false image is lower than 
 the true one, for the dotted line extends lower than the other one. 4. 
 That the diplopia occurs in downward movements of the eyes, for it is 
 in the lower half of the diagram that the false image hes. 
 
 " The same rules apply to the obliques (Fig. 336), with one difference. 
 The recti move the eye in the direction indicated by their names, the 
 superior moving it upward and the inferior downward; but in the case 
 of the obUques the reverse takes place, the superior obhque moving the 
 eye downward and the inferior upward. Therefore for the superior 
 obhques we must look at the lower half of the figure, and for the inferior 
 obliques at the upper part. 
 
 "With these figures it is possible to tell what kind of diplopia would 
 result from paralysis of any one of these muscles, and conversely, given 
 the diplopia, to determine to which muscle it is due." 
 
 Paralysis of the Third Nerve. — With complete paralysis 
 of this nerve there is ptosis; the eyeball is almost immobile, 
 the limitation of motion being upward, downward, and in- 
 ward; the eye deviates outward and somewhat downward, with 
 the upper end of the vertical rheridian inclined inward, espe- 
 cially on looking downward; the face is directed upward and 
 toward the sound side, and the head inclined to the shoulder 
 of the paralyzed side. There is slight exophthalmos due to 
 
PARALYSIS OF THE THIRD NERVE 369 
 
 paralysis of the three recti which normally draw the eyeball 
 backward; the pupil is dilated and is immobile; accommodation 
 is paralyzed; there is crossed diplopia — the false image is 
 higher, and its upper end inclined toward the paralyzed side. 
 
 Paralysis of the third nerve is common; it is often incom- 
 plete, two or three of the muscles being affected. It may be 
 associated with paralysis of other nerves. 
 
 When all the muscles of one eye are paralyzed, including 
 the iris and ciliary body, the condition is known as total oph- 
 thalmoplegia. 
 
 When all the exterior myscles of the eyeball are paralyzed, 
 but not the iris and ciliary body, the condition is known as 
 external ophthalmoplegia; this variety is more common than 
 total ophthalmoplegia; the nuclei for the sphincter pupillse 
 and ciliary muscle being separate, they often escape involve- 
 ment of lesions affecting the origin of the exterior ocular 
 muscles; this form is generally of central (nuclear) origin. 
 
 Paralysis limited to the sphincter pupillse and the ciliary 
 muscle is known as internal ophthalmoplegia (p. 355). 
 
 Associated or Conjugate Paralyses involve associated muscles, 
 such as the external rectus of one eye and the internal rectus 
 of the other; they are due to lesions in the association centres. 
 
 Etiology. — The lesions causing paralysis may be situated 
 anywhere in the course of the nerve tract, from the cerebral 
 cortex to the muscle. According to its site, the lesion is dis- 
 tinguished as central and peripheral. Central lesions may be 
 situated in the cortical centres (cortical paralysis), the associa- 
 tion centres, the nuclei of origin (nuclear paralysis), or in the 
 fibres which connect these centres. Peripheral lesions may 
 affect the nerves in some part of their course, either between 
 the point where they issue from the brain and their entrance 
 into the orbit (basilar paralysis), or in the nerve or its 
 branches in the orbit (orbital paralysis). 
 
 The Differential Diagnosis between Central and Peripheral 
 Paralysis is not always easy; it is based on the character of 
 the paralysis and the accompanying symptoms. Complete 
 paralysis, unaccompanied by any other symptoms, is gener- 
 ally peripheral. When central, the paralysis is generally less 
 
370 DISTURBANCES OF MOTILITY OF THE EYE 
 
 complete, more than one muscle is usually involved, there are 
 apt to be cerebral symptoms, and there is commonly an ab- 
 sence of peripheral cause. 
 
 The Nature of the Lesion. — The lesion may be a neighboring . 
 exudation, hemorrhage, periostitis, timior, injury, or vascular 
 change, causing compression or inflammation of the nerves; 
 less frequently, primary inflammation or degeneration. 
 
 The most common cause is syphilis (late symptom), which 
 is responsible for one-half the cases. Other causes are rheu- 
 matism and gout, exposure to cold, diphtheria, locomotor ataxia 
 and other spinal affections, tuberculous meningitis and other 
 cerebral affections, diabetes, acute infectious diseases (espe- 
 cially influenza), toxic agents (including ptomain poisoning), 
 and injuries. Occasionally paralysis is congenital. 
 
 Prognosis varies with the cause. Peripheral paralyses due 
 to syphilis, rheumatism, and cold usually get well, but may 
 relapse. In the paralysis accompanying serious spinal and 
 cerebral disease, the prognosis is often bad. Long-neglected 
 paralyses present an unfavorable prognosis, on accoimt of the 
 atrophy of the paralyzed muscle and the contraction of the 
 antagonist. The course is always chronic, and even in favor- 
 able cases, several weeks or months are required to effect a cure. 
 
 Treatment should be directed to the cause. In syphilis, mer- 
 cury and large doses of potassic iodide are given. In rheu- 
 matism and gout, salicylate of sodium, iodide of potassium, 
 and colchicum, singly or combined, are prescribed. In diph- 
 theria, strychnine is indicated. In obscure cases, potassic 
 iodide with or without mercury is usually resorted to. Hot 
 baths and diaphoresis are sometimes employed. 
 
 Locally, we may use massage, electricity, muscle-stretching, 
 ocular-muscle exercises, prisms, and occlusion of one eye. In 
 incurable cases, operative intervention is resorted to. 
 
 Massage, applied either directly upon the affected muscle or 
 through the lids, is a simple procedure which is sometimes of 
 value, especially when a single muscle is involved. 
 
 Electricity may be tried; the constant current (2 milliam- 
 pSres) is used, the negative pole being applied to the back of 
 the neck, and the positive over the affected muscle. 
 
TREATMENT OF OCULAR PARALYSES 371 
 
 When the paralysis remains obstinate, muscle-stretching 
 may be used. Under local anaesthesia, the conjunctiva over the 
 insertion of the paralyzed muscle is seized with a fixation for- 
 ceps, and the eye forcibly rotated to and fro a number of times 
 during two or three minutes, so as alternately to stretch and 
 relax the affected muscle. 
 
 The paralyzed muscle may be exercised by allowing the pa- 
 tient to look through a prism which almost corrects the diplo- 
 pia, thus coaxing the muscle into action; or by having the 
 patient turn his head until the double images almost coalesce, 
 and then make a strong effort to fuse them without any fur- 
 ther motion of the head. 
 
 In chronic cases with moderate paresis, prisma may neutral- 
 ize the diplopia and thus add to the patient's comfort. 
 Prisms stronger than 5° for each eye (10° in all) cannot be 
 worn on account of their weight and chromatic aberration. 
 
 During the course of treatment, the deviating eye should be 
 occluded by a patch or a ground glass in an ordinary spectacle 
 frame, so as to prevent the annoying diplopia. 
 
 If the condition persists for a long period in spite of all 
 treatment, and the paralysis seems incurable, operative treat- 
 ment is indicated. This consists in an advancement of the 
 paralyzed muscle, combined in many cases with tenotomy of 
 the antagonist. The results of this operation are often disap- 
 pointing, but the cosmetic improvement may be satisfactory. 
 
 STBABISMTTS 
 
 Strabismus (Concomitant Squint or Heterotropia) is a mani- 
 fest deviation of the visual line of one eye, due to absence of bi- 
 nocular fixation, the two eyes maintaining the same faulty rela- 
 tionship of axes in every direction in which they are turned. 
 The power of the different muscles of the two eyes is usually 
 normal, and the squinting eye follows the other in all its move- 
 ments, always deviating from the correct position to the same 
 extent, and the visual lines remaining at the same angle; on this 
 account, the condition is known as concomitant squint; it is a 
 state of faulty co-ordination of the two eyes. The eye which 
 
372 DISTURBANCES OF MOTILITY OF THE EYE 
 
 is directed toward the object looked at, is known as the fixing 
 eye, the other as the squinting eye. 
 
 Strabismus differs from heterophoria as explained on p. 361. 
 It is distinguished from paralytic squint by presenting a nor- 
 mal range of movement of each eye, and the same deviation in 
 all parts of the visual field, while in paralysis the deviation is 
 present only in the sphere of action of the paralyzed muscle, 
 and there is limitation of movement in a certain direction; in 
 concomitant squint, the primary and secondary deviations 
 are equal, while in paralytic squint the secondary deviation is 
 greater than the primary; diplopia, a prominent symptom in 
 paralytic squint, is seldom present in concomitant squint. 
 
 Varieties. — Squint is said to be 
 
 1. Periodic or Occasional, when present only at times, as 
 after accommodating excessively, or when the system is de- 
 ranged. This variety may disappear with non-operative 
 treatment, or pass into the constant variety. 
 
 2. Constant, when always present. Either of these two 
 varieties may be alternating or monocular. 
 
 3. Alternating, when the patient fixes with either eye indif- 
 ferently, the vision in the two eyes being about equal; or else 
 one eye fixes for distance, and the other for near vision. 
 
 4. Monocular, when the same eye habitually deviates; the 
 vision in this eye is often below that of the other. 
 
 According to direction of deviation, squint is divided 
 into — 
 
 (a) Internal Squint (Strabismus Convergens, Esotropia), 
 the commonest form. 
 
 (6) External Squint (Strabismus Divergens, Exotropia). 
 
 (c) Vertical Squint (Hypertropia; Strabismus Sursum Ver- 
 gens, when upward; Strabismus Deorsum Vergens, when down- 
 ward); this form is uncommon. Some vertical deviation, 
 usually upward, frequently accompanies convergent squint. 
 
 Diagnosis can usually be made, qualitatively, by inspec- 
 tion; in slight degrees this cannot be depended upon. The 
 cover test is a simple method: The patient is directed to fix a 
 distant object and a card or the hand placed alternately over 
 one and then over the other eye; if, when one eye is covered, 
 
STRABISMUS 
 
 373 
 
 Fig. 337. — The Measurement 
 ofSquint by the Linear 
 Method. 
 
 the other has to move outward or inward in order to fix the 
 object, it was previously squinting inward or outward. 
 
 The Measurement of Squint. — The amount of strabismus 
 may be measured by (1) markings on the lower hd, (2) by 
 the strabismometer, and (3) by the perimeter. 
 
 The Linear Method presents a simple and fairly accurate 
 measure (Fig. 337). The patient is directed to fix a distant 
 object situated in the median line; the 
 position of the outer margin of the 
 cornea of the squinting eye is marked 
 upon the lower lid margin (S, Fig. 337). 
 Next, we cover the fixing eye and tell 
 the patient to look at the same distant 
 object with the squinting eye; the loca- 
 tion of the outer margin of the cornea 
 is again marked upon the border of the 
 lower lid (F, Fig. 337). The distance between the two marks 
 (FS) gives the linear measure of the squint. Thus we say 
 a squint of 2 lines, 4 mm., etc. 
 
 The Strabismometer (Fig. 338) is a small 
 ivory plate, having an upper margin curved 
 to conform to the lower Ud, and marked 
 with the inch or millimeter scale, by which 
 the deviation of the centre of the pupil in 
 the fixing and the squinting positions is 
 measured. 
 
 The Perimeter (Fig. 19) gives the angu- 
 lar measurement of squint: The patient is 
 seated with the squinting eye in the centre 
 of the instrument, and is directed to fix a 
 distant object placed in the median line, 
 with both eyes; the quadrant is placed 
 horizontal when the squint is convergent or 
 divergent; alighted candle is now moved 
 along the inside of the arc from the centre 
 outward, until its reflection on the cornea is seen in the centre 
 of the pupil of the squinting eye; the number of degrees on 
 the arc at this point indicates the size of the strabismus angle. 
 
 Fig. 338.— The Strabis- 
 mometer. 
 
374 DISTURBANCES OF MOTILITY OF THE EYE 
 
 Symptoms. — The disfigurement is the symptom which usu- 
 ally leads the patient to consult an oculist. There is no diplo- 
 pia except in the very early stages, the double images soon 
 disappearing owing to a psychical process of excluding the 
 image of the squinting eye. There is usually diminution in 
 the acuteness of vision of the deviating eye. This may or may 
 not have existed previous to the development of strabismus; 
 in either case, it increases with the duration of the squint from 
 disuse (amblyopia ex anopsia), and may finally become very 
 pronounced. There are no asthenopic symptoms. 
 
 Etiology. — Concomitant squint is generally the result of an 
 interference with the normal fusion of the macular images of 
 the two eyes, dependent upon a defect of the fusion faculty. In 
 the infant, the motor co-ordinations of the eyes serve to main- 
 tain an approximate parallelism of the visual axes. The 
 fusion faculty soon begins to develop and is complete before 
 the sixth year; this establishes a desire for binocular vision 
 which keeps the eyes straight. " Sometimes, however, owing 
 to a congenital defect, the fusion faculty develops later than 
 it should, or it develops very imperfectly, or it may never 
 develop at all. Then there is nothing but the motor co- 
 ordinations to preserve the normal relative directions of the 
 eyes, and anything which distiu'bs the balance of these co- 
 ordinations will cause a permanent squint " (Worth). 
 
 In the presence of a defect of the fusion faculty, the eyes 
 are in a state of unstable equilibrium, ready to squint on slight 
 provocation. Such exciting causes may be (1) disturbance in 
 the relation between accommodation and convergence by 
 errors of refraction, (2) anisometropia, (3) imperfect vision in 
 one eye due to congenital amblyopia, opacities of the media, 
 and intraocular diseases, (4) disparity in the length or thick- 
 ness of opposing muscles. 
 
 CONVBEGENT CONCOMITANT STRABISMUS 
 
 In this form of squint (esotropia) there is deviation inward 
 of the visual line of one eye (Fig. 339). It is generally asso- 
 ciated with hyperopia, with or without hyperopic astigma- 
 tism; rarely it occurs in myopia and in emmetropia. It usu- 
 
CONVERGENT CONCOMITANT STRABISMUS 375 
 
 ally commences in early life, between the first and fourth years, 
 when the child begins to use his accommodation for near 
 objects, such as toys and pic- 
 tures; rarely it is congenital. 
 At first the squint may be 
 noticed only at times (period- 
 ic), with near vision, or when 
 there is any interference with 
 
 - the general health; but it is Fig. 339.— convergent strabismus. 
 
 apt to become constant for 
 
 both near and distant vision; occasionally it disappears 
 
 spontaneously. 
 
 The acuteness of vision in the squinting eye often presents 
 considerable reduction, and there may be marked amblyopia. 
 Whether the squint precedes and is the cause of the amblyo- 
 pia, or whether the amblyopia is originally present and is the 
 cause of the squint, is one of the unsettled questions in oph- 
 thalmology; probably in most instances the amblyopia is ac- 
 quired from disuse of the squinting eye. 
 
 The frequent association of convergent squint and hyperopia 
 depends upon the close connection between accommodation 
 and convergence. A child who is hyperopic must use some ac- 
 commodation for distance, and more for near vision. Accom- 
 modation and convergence being associated, he must increase 
 his convergence with increase of accommodation. In looking 
 at a near object, the stimulus to converge corresponds not 
 only to the amount present in the emmetrope, but includes an 
 additional and abnormal amount called for by the extra ac- 
 commodation required to compensate for his hyperopia. 
 Hence the point of convergence is nearer than the distance 
 acconmiodated for and convergent squint results. 
 
 Treatment comprises (1) the correction of refractive errors 
 by glasses, (2) exercise of the squinting eye by occluding its 
 fellow, (3) instillation of atropine, (4) the training of the 
 fusion sense (orthoptic training), and (5) operation. 
 
 Non-Operative Treatment. — The eiror of refraction should 
 be estimated under homatropine or atropine, and convex glasses 
 correcting very nearly the total hyperopia (also the astigma- 
 
376 DISTURBANCES OF MOTILITY OF THE EYE 
 
 tism, if present) prescribed for constant wear. In slight cases, 
 especially if periodic, this sometimes effects a cure. Glasses 
 may be worn by children of two years and upward. It is 
 sometimes advisable to keep the eyes under the influence of 
 atropine for a week when the glasses are first worn. 
 
 The fixing eye should be covered by a patch or bandage for 
 one hour, three times a day, or the occlusion may be continu- 
 ous. This compels the squinting eye to fix, exercises it, pre- 
 vents amblyopia from disuse, and restores, as far as possible, 
 the sight of the deviating eye if amblyopia already exists. 
 
 Atropine should be instilled into the fixing eye so that the 
 latter cannot be used for near vision, thus compelUng the 
 child to employ the squinting eye for seeing close objects. One 
 drop of a 1-per-cent. solution or ointment is used every morn- 
 ing; the practice may be kept up for months. 
 
 Orthoptic Training of binocular perception and the sense of 
 fusion may be undertaken with stereoscopes, but most success- 
 fully with the amblyoscope (Fig. 340). 
 
 This instrument consists of two brass tubes joined by a hinge, each 
 provided with a mirror and a convex lens. The object-slides are devices 
 
 Fig. 340. — ^Worth's Amblyoscope. 
 
 drawn on translucent paper gummed on glass, or printed on celluloid 
 squares (Fig. 341). The two halves of the instrument can be brought 
 
TREATMENT OF INTERNAL SQUINT 377 
 
 together to suit a convergence up to 60°, or separated to suit a diver- 
 gence of 30°. Each object-slide is lighted by a separate electric lamp, 
 the briUiancy of which can be regulated, thus increasing or diminishing 
 the illumination of either of the pictures. 
 
 The Amblyoscope is used as follows: The instrument is 
 adapted roughly to the angle of the child's squint and the ex- 
 ercises are begun by an attempt to develop simultaneous per- 
 ception, by increasing the illumination before the squinting 
 
 V 
 
 Fig. 341. — Object-slides used with Worth's Amblyoscope. 
 
 eye and adjusting the relative briUiancy of the lights, until the 
 objects of both slides are seen simultaneously; then the child 
 is taught to fuse the images; finally the amplitude of fusion is 
 increased, and the sense of perspective taught. 
 
 Non-operative treatment is successful in a large proportion 
 of cases of convergent concomitant squint, if used sufficiently 
 early. The earlier such treatment is begun, the better the 
 results; after the sixth year it is not usually effective. 
 
 Operative Treatment. — If non-operative measures do not 
 overcome the deviation after a lengthy trial, operation is indi- 
 cated. It is not customary to operate before the seventh year; 
 it is generally advisable to postpone operation until the child 
 is old enough to allow local anaesthesia and to aid by its co- 
 operation, since the results are better and more certain under 
 such circumstances. In cases in which it was found impos- 
 sible to develop the fusion faculty, operation relieves the dis- 
 figurement but fails to give binocular single vision. 
 
 Two operative procedures, tenotomy of an internal rectus, 
 and advancement of an external rectus, are employed either 
 singly or in combination. Tenotomy of an internal rectus 
 consists in a division of this muscle at its insertion, allowing 
 the eye to rotate outward. In advancement, the tendon is sep- 
 
378 DISTURBANCES OF MOTILITY OF THE EYE 
 
 arated at its insertion, often shortened, and the cut end secured 
 to the eyeball nearer the cornea than the original insertion. 
 
 The choice of operation depends upon the amount of squint, 
 the lateral excursions of both eyes, the amount of amblyopia 
 in the squinting eye, and upon other conditions brought out 
 by careful examination. The relative advantages of tenot- 
 omy and advancement have been much discussed. Tenotomy 
 is much the easier operation, quickly performed, inflicting little 
 if any pain when done under local anaesthesia, and causing but 
 slight inconvenience to the patient. Advancement,, on the 
 other hand, is more difficult, takes longer, is not entirely free 
 from pain, may require a general anaesthetic, and the patient 
 is confined to the house for several days. A good general rule 
 is to resort to tenotomy when there is considerable overaction 
 of the internal recti with normal power of the externi, and to 
 advance one or both externi when there is relaxation of these 
 muscles with decided limitation in abduction; but advance- 
 ment has certain advantages over tenotomy which make it the 
 more satisfactory operation in general, and the one preferred 
 probably by most ophthalmic surgeons. Deviations of more 
 than 25° are best corrected by an advancement of the external 
 rectus and a tenotomy of the internal rectus. 
 
 The estimation of the result likely to follow operative treat- 
 ment requires considerable judgment and exjjerience. A free 
 tenotomy of one internal rectus will usually diminish an inter- 
 nal squint to the extent of about 13° (3 to 4 nmi.). An ad- 
 vancement, if successfully carried out, will produce any degree 
 of rotation of the globe. As a rule, only one internal rectus 
 should be divided at a time, unless the squint be very marked, 
 since it is difficult to gauge the after-effect correctly. The 
 full effects of such operations frequently are seen only after 
 several months; if too much has been done, there will be di- 
 vergence. In young children, a general anaesthetic is often 
 required; in older children, local anaesthesia will suffice. 
 
 DIVERGENT CONCOMITANT STBABISMTTS 
 
 This form of squint exists when one eye fixes an object and 
 the other deviates outward (Fig. 342). It is usually associated 
 
Fig. 342. — Divergent Strabismus. 
 
 DIVERGENT CONCOMITANT STRABISMUS 379 
 
 with myo-pia, but may occur with other errors of refraction. 
 It is also observed after tenotomy for the cure of internal 
 squint, and when the fusion 
 faculty is defective or the 
 sight in one eye is deficient or 
 abolished, as in opacities of 
 the media, ocular disease and 
 injury, and in blindness; in 
 these cases, binocular vision 
 being impossible, there is no need for convergence. Di- 
 vergent squint is much less frequent than convergent. 
 
 Association with Myopia. — In myopia little or no accom- 
 modation is needed for near vision; consequently, there is an 
 habitual deficiency of the stimulus for convergence, and a ten- 
 dency to relax the internal recti muscles. Again, the exces- 
 sive convergence necessary to see near objects within the far 
 point causes fatigue of the interni, giving rise to muscular 
 asthenopia (p. 348); to relieve this, one of the internal recti 
 muscles relaxes, and the eye turns out, especially if the sight 
 in this eye is defective. Another predisposing cause is the 
 increased antero-posterior diameter of the eyeball, which me- 
 chanically limits convergence. 
 
 Unlike convergent squint, the condition is infrequent in 
 very young children. It develops during youth, when near- 
 sightedness is established, and the tendency increases with the 
 degree of myopia; when the latter reaches a high degree, the 
 far point is so close, that it is impossible to maintain the neces- 
 sary convergence, and divergence becomes inevitable. At 
 first the squint is manifest only during near use of the eyes 
 {periodic) ; but it usually progresses and is present in distant 
 as well as with near vision {constant). 
 
 Treatment. — In recent cases, when the squint is still peri- 
 odic and the patient's vision is good, we may cure the squint 
 by giving the full correcting lenses. In other cases, especially 
 those of long duration, operation is indicated. The best results 
 are obtained from advancement of one or both internal recti. 
 
380 DISTURBANCES OF MOTILITY OF THE EYE 
 
 Fig. 344. — Toothed Forceps. 
 
 Fig. 345. — Eye Speculum. 
 
 r 
 
 Fig. 346. — Fine Curved and 
 Halt-Curved Needles. 
 
 Fig. 347. — Large and 
 Small Squint Hooks. 
 
 Fig. 348. — Curved 
 Strabismus Scissors. 
 
 Fig. 350. — Advancement Forceps. 
 
 Figs. 343 to 350. — Instruments Required tor Tenotomy and Advancement of the 
 
 External Ocular Muscles. 
 
OPERATIONS FOR STRABISMUS 
 
 381 
 
 TENOTOMY 
 
 The following description applies to tenotomy of the right 
 internal rectus. The methods of operating employed most 
 frequently are the siibco7ijiinctival and the open. 
 
 Instruments Required. — (1) Eye speculum (Fig. 345); (2) 
 fixation forceps (Fig. 343); (3) toothed forceps (Fig. 344); 
 (4) blunt-pointed, curved strabismus scissors (Fig. 348); (5) 
 two squint hooks (Fig. 347); (6) needle holder (Fig. 349); 
 (7) fine curved and half-curved needles (Fig. 346); and thin 
 black silk. 
 
 The Subconjunctival Method. — The speculum is introduced 
 and the eyeball drawn outward, if necessary, by an assistant. 
 The conjunctiva over the lowest portion of the insertion of the 
 muscle, together with the sub- 
 conjunctival tissue and Ten- 
 on's capsule, is seized with 
 the toothed forceps, raised 
 and divided with scissors; the 
 first cut divides the conjunc- 
 tiva, the second Tenon's cap- 
 sule. Keeping the fold raised 
 with the forceps, a strabis- 
 mus hook is introduced 
 through the opening, passed 
 beneath the tendon, and pushed upward until its point is seen 
 through the conjunctiva at the upper border of the muscle. 
 The hook is transferred to the left hand and raised so as to 
 lift the tendon. The scissors are taken in the right hand and 
 introduced, one branch between the tendon and conjunctiva, 
 and the other between the tendon and sclera; the tendon is 
 divided close to the sclera by two or more small cuts. The 
 hook is reintroduced to make sure that no portion of the ten- 
 don has been left undivided. If the tendon has been com- 
 pletely divided, the hook can be advanced to the cornea with- 
 out resistance; if not, the undivided fibres must be cut with 
 scissors. The hook is again introduced and swept from be- 
 hind forward, above, and below, to ascertain whether there 
 are any uncut fibres of attachment to the sclera which, if 
 
 Fig. 351. — Tenotomy of the Internal Rectus. 
 
382 DISTURBANCES OF MOTILITY OF THE EYE 
 
 found, must be severed. The conjunctival wound is closed 
 with one or two vertical sutures. 
 
 The Open Method. — The steps are the same as in the preced- 
 ing operation except that the muscle is exposed. The con- 
 junctiva is incised about 2 mm. from the corneal margin, and 
 dissected backward and downward beyond the lower border of 
 the muscle. The liook is inserted beneath the fully exposed 
 tendon, which is raised and divided close to the sclera (Fig. 
 351). The wound is closed by two vertical sutures. 
 
 After-Treatment. — The result of the operation should be 
 noted after completion (if done under local anaesthesia). It 
 may be necessary to lessen the effect by a suture which 
 stitches the muscle forward to the insertion of the tendon; or to 
 increase the effect by again introducing the hook and dividing 
 the upper and lower expansions of the insertion of the tendon. 
 
 There should always be some convergence (5°) left after the 
 operation suice, although the primary result usually dimin- 
 ishes for a few days, the subsequent effect increases for a num- 
 ber of months; hence if the immediate correction be perfect, 
 there is apt to be subsequent divergence. 
 
 If we desire to increase the effect of the operation, atropine 
 is instilled and both eyes bandaged for a few days; otherwise 
 this is urmecessary. There is usually no great reaction; the 
 eye will be congested, but not painful. The bandage can be 
 left off in a day or two. Sometimes there is slight deformity 
 caused by a sinking of the caruncle, the result of free division of 
 Tenon's capsule. Infection occurs in rare instances, emphar 
 sizing the necessity for strict asepsis. 
 
 ADVANCEMENT OF AN OCULAB. MUSCLE 
 
 Advancement brings the attachment of the muscle forward; a 
 considerable degree of rotation of the eyeball may be pro- 
 duced. For slight deviations, it will be sufficient to advance 
 the muscle without tenotomizing the opponent; for squints of 
 greater degree, it is best to include a tenotomy upon the oppos- 
 ing muscle. There are many methods of advancement; the 
 Worth operation, one of the best, is performed as follows: 
 
 The instruments required are the same as those needed for 
 
ADVANCEMENT OF AN OCULAR MUSCLE 
 
 383 
 
 tenotomy, with the addition of advancement forceps (Fig. 
 350). A general anesthetic is sometimes required, but in 
 most instances local ancesthesia is sufficient. After insertion 
 of the speculum, the conjunctiva is grasped with the toothed 
 forceps and a straight vertical incision made, the middle of 
 which is close to the cornea; a similar incision is made through 
 the capsule of Tenon; the conjunctiva and capsule retract or 
 are pushed back, so as to expose the insertion of the tendon. 
 
 One blade of the advancement forceps is passed under the 
 tendon, after the manner of a tenotomy hook and the forceps 
 closed, so that ten- 
 don, capsule of Te- 
 non, and conjunctiva 
 are firmly clamped 
 together, with their 
 relations undisturbed 
 (Fig. 352). The ten- 
 don is now divided 
 with scissors at its in- 
 sertion into the scle- 
 rotic. The exposed 
 and separated muscle 
 is now held by the 
 forceps, together with 
 the overlying capsule of Tenon and conjunctiva, and these 
 parts are secured in loops of thread, inclosing the upper and 
 the lower fourth respectively. After tying, one end of each 
 thread is passed through the tough circumcorneal episcleral 
 tissue. 
 
 The anterior part of the muscle, capsule, and conjunctiva 
 are removed, by cutting them through with scissors behind 
 where they are grasped by the forceps. The gap is then 
 closed by tightening and securely tying each suture at HH, 
 so that the eyeball is rotated in its correct position, and the 
 anterior end of the muscle is brought nearly up to the corneal 
 margin at GG (Fig. 352). 
 
 The eye is bandaged, and the patient kept in bed for twenty- 
 four hours, and confined to his room for two or three days. 
 
 Fig. 352.- 
 
 Worth's Operation of Advancement of an 
 Ocular Muscle. 
 
384 DISTURBANCES OF MOTILITY OF THE EYE 
 
 The stitches are usually allowed to remain in a week, unless 
 we wish to diminish the effect of the operation. If properly 
 performed, the inmiediate effect produced is the final result. 
 
 HETEBOPHOBIA 
 
 Heterophoria (Insufficiency) is a condition in which the 
 eyes have a constant tendency to deviate, but are forced into 
 simultaneous fixation of an object by special exertion. If this 
 effort were not made, there would be a slight deviation and 
 double images. So as to secure binocular vision and avoid 
 diplopia, an excessive amount of innervation is employed to 
 maintain proper thongh forced balance. When one eye is cov- 
 ered, diplopia cannot occur; hence the eye will deviate; its 
 direction now represents the position of rest. The condition 
 differs from concomitant squint; in the latter affection, the 
 deviation is due to an absence of the power of binocular fixa- 
 tion and cannot be overcome by increased innervation. 
 
 Varieties. — The following terms ate employed for designat- 
 ing the various forms of normal and faulty muscular balance: 
 
 Orthophoria, perfect muscle balance. 
 
 Heterophoria, imperfect muscle balance. 
 
 £^a;op/iom, tendency to deviate outward (latent divergence). 
 
 Esophoria, tendency to deviate inward (latent convergence). 
 
 Hyperphoria, a tendency of one eye to deviate upward; right 
 hyperphoria, when the right eye tends to deviate upward; left 
 hyperphoria, when the left eye tends to deviate upward. 
 
 Hyperexophoria and hyper esophoria, a combination of hy- 
 perphoria with exophoria and esophoria respectively. 
 
 Cyclophoria, want of equilibrium of the oblique muscles. 
 
 Etiology. — The chief cause is some error of refraction, espe- 
 cially when accompanied by some disturbance in the normal 
 relationship between accommodation and convergence. Another 
 very common cause is general lack of muscular tone seen in 
 delicate individuals and in convalescence. Much less fre- 
 quently, certain anatomical conditions, such as a defect or 
 weakness, or abnormality in size or insertion of one of the 
 muscles, is responsible. The condition is very common. 
 
 S3rmptoms. — In slight degrees of heterophoria, there are 
 
HETEROPHORIA 385 
 
 very often no symptoms whatever. In more pronounced forms, 
 the symptoms of muscular asthenopia are present: Headache, 
 various neuralgias, mental dulness, pain in the eyes, indis- 
 tinctness or " running together " of print, diplopia, vertigo, 
 and irritable condition of the lids. In exophoria, these symp- 
 toms are complained of most after use of the eyes for near 
 work, in esophoria with distant vision. Sometimes the patient 
 complains of one eye turning in or out. Not infrequently 
 there is a feeling of ocular soreness in the morning upon awak- 
 ening. The dependence of epilepsy, chorea, and other serious 
 nervous disorders upon heterophoria is extremely doubtful, 
 but neurasthenia and disturbances of digestion and nutrition 
 may be the result of the muscular error in predisposed 
 individuals. 
 
 Tests are usually carried out both at 20 feet and at 13 
 inches. The test object for distance is a candle flame, and for 
 near, a black spot (1 to 2 mm.) upon a white card. The deAa- 
 ation, being latent, is revealed only by certain tests. When 
 the eyes are in a state of perfect balance, there is orthophoria for 
 distance, and usually a slight exophoria (2° to 3°) for near. 
 
 The Cover Test. — The patient is directed to look at a distant 
 object (20 feet), placed in the median line on a level with his 
 eyes. A card is placed over one eye, and then over the other 
 alternately, and the examiner notes the position and move- 
 ment of the eye at the moment of imcovering. If on exposing 
 the right eye and placing the card over the left, the right eye 
 moves in, in order to fix the object, there must have been a 
 deviation outward when covered (exophoria). If on being 
 uncovered the eye moves out, there is esophoria. If when the 
 right eye is uncovered it moves down, there is right hyper- 
 phoria;, if it moves up, there is left hyperphoria. 
 
 The test is repeated for a near object held in the median line 
 and on a level with the patient's eyes, at about 13 inches. 
 
 The amount of movement of readjustment is proportional 
 to the degree of deviation. Deviations of 2° or more are 
 readily discovered by this test. 
 
 The Fixation Test. — The patient is directed to fix a small 
 object, held in the median line on a level with the patient's 
 
386 DISTURBANCES OF MOTILITY OF THE EYE 
 
 Pig. 353. — Maddox Rod. 
 
 eyes, and slowly advanced toward his nose, to within two 
 inches. If there is weakness of the interni (exophoria), one of 
 the eyes will deviate outward before this convergence near 
 point is reached. 
 
 The Maddox Rod (Fig. 353) is a 
 piece of glass rod set in a hard-rub- 
 ber disc, so as to fit into the trial 
 frame. It converts the image of the 
 flame perceived by one eye into a 
 long streak of light (Fig. 354), so 
 that there remains no desire to unite 
 it with the image of the other eye. 
 The line is always at right angle to 
 the axis of the rod. 
 The Maddox rod is placed horizontal before the right eye, 
 converting its image of the candle flame into a vertical streak. 
 If orthophoria is present, this streak appears to pass directly 
 through the im- 
 age seen with 
 the other eye 
 (Fig. 354). If 
 the line of light 
 appears to the 
 left of the flame, 
 there is crossed 
 diplopia, indi- 
 cating exoph- 
 oria (Fig. 355) ; if to the right of the flame, there is homony- 
 mous diplopia, indicating esopAona (Fig. 356). The amount 
 of heterophoria is measured by the prism, base in or out, 
 which serves to displace the streak until it runs directly 
 through the flame. 
 
 The rod is then placed vertical before the right eye, convert- 
 ing the image of this eye into a horizontal line of light, which 
 will pass through the image of the left eye (Fig. 357) if ortho- 
 phoria prevails. If this is below the image of the flame seen 
 with the left eye, there is right hyperphoria (Fig. 359) ; if above, 
 there is left hyperphoria (Fig. 358). The degree of hyper- 
 
 PiG. 354. 
 
 Fig. 355. 
 
 Pig. 356. 
 
 Fig. 354. — The Maddox Rod Test in Orthophoria. 
 Fig. 355. — The Maddox Rod Test in Exophoria. 
 Fig. 356. — The Maddox Rod Test in Esophoria. 
 
TESTS FOR HETEROPHORIA 
 
 387 
 
 
 H 
 
 1 
 
 L 
 
 1 
 
 L 
 R 
 
 Fig. 357. Fig. 358. Fig. 359. 
 
 Fig. 357. — The Maddox Rod in Orthophoria. 
 Fig. 358. — The Maddox Rod in Left Hyperphoria. 
 Fig. 359. — The Maddox Rod in Right Hyperphoria. 
 
 phoria is measured by the prism, base up or down, which 
 causes the light streak to pass directly through the flame. 
 
 Any strong convex cylinder answers the same purpose. The 
 Maddox rod is sometimes made of red glass, or a red glass is 
 held in front 
 of one eye, so 
 as to color one 
 image and thus 
 effect a still 
 greater reduc- 
 tion in the ten- 
 dency to fuse 
 the two images. 
 A piece of red 
 
 glass held in front of one eye is sufficient in itself to cause 
 diplopia, whenever the heterophoria is marked. 
 
 The Graefe Test consists in placing a prism of 8°, base up 
 or down, before one eye, thus causing vertical diplopia. If 
 
 there is orthophoria, one image of 
 the flame at 20 feet appears directly 
 below the other. But if there is a 
 lateral heterophoria, a lateral sepa- 
 ration of the images is added to the 
 vertical displacement caused by the 
 prism. A second prism, base in or 
 out, which brings one image exactly 
 over the other, is the measure of the 
 heterophoria. 
 
 This test is frequently used for 
 estimating the disturbance of equi- 
 librium with near vision. A black 
 dot (2 mm.), and a vertical line 2 
 or 3 inches long passing through its 
 centre, are drawn upon a white card. 
 The latter is held at 13 inches, and a prism of 8°, base up or 
 down, is placed before one eye. If there is orthophoria, the 
 double images of the dot will appear one above the other 
 (Fig. 360); if heterophoria, they will be displaced laterally, 
 
 R R R 
 
 \ \ \ 
 
 I I I 
 
 I I I 
 
 < I I 
 
 I I 
 
 I I J 
 
 i. L L 
 
 Fig. 360. Fig. 361. Fig. 362. 
 
 Fig. 360.— The Graefe Test. 
 Orthophoria. 
 
 Figs. 361 and 362.— The 
 Graefe Test. Heterophoria. 
 
388 DISTURBANCES OF MOTILITY OF THE EYE 
 
 and there will be two dots and two lines (Figs. 361 and 362). 
 The prism, base in or out, which brings them in the same ver- 
 tical line is the measure of the deviation. 
 
 The Phorometer (Fig. 363) furnishes a rapid and convenient 
 means of applying the Graefe test. It consists of a pair of 4° 
 prisms. The latter are first placed with their bases up and 
 down so as to produce vertical diplopia; if the double images 
 
 Fig. 363. — The Stevens Phorometer (the base and upright have been omitted from the 
 
 illustration). 
 
 do not appear one exactly over the other, there is exophoria 
 or esophoria; by rotation of the prisms, the images can 
 be brought in a vertical line, and the degree of rotation 
 required read off on an attached arc indicates the amount of 
 exophoria or esophoria. Hyperphoria is determined in a sim- 
 ilar manner, the prisms being placed with their bases in. The 
 test object for near is a small metal plate, in the centre of 
 which is a small cross with perforation. 
 
 Risley's Rotary Prism (Fig. 364) is another convenient in- 
 strument for the detection and estimation of muscular errors. 
 
 It is important to measure the power of the muscles in adduc- 
 tion, abduction, and sursumduction, as expressed by the 
 strongest prism which can be overcome. Adduction or prism 
 convergence is determined by ascertaining the strongest prism, 
 base out, which the eyes can overcome — i.e., converge so as to 
 prevent diplopia; in normal eyes this amounts to a prism of 
 20° to 30°. Abdud,ion or prism divergence is determined by 
 the strongest prism, base in, which the eyes can overcome; it 
 is represented normally by a prism of 6° to 8°. The usual 
 
TREATMENT OF HETEROPHORIA 389 
 
 relationship between adduction and abduction is about 3 to 1 ; 
 the power of adduction can, however, be increased by prac- 
 tice. Sursumduction or the power of vertical divergence is 
 measured by the strongest prism, base up or down, that can 
 be overcome; it is usually represented 
 by a prism of 2° or 3°. 
 
 Treatment consists in correction of 
 the error of refraction, attention to 
 the general health, prism exercises, 
 the wearing of prisms, and as a last 
 resort, operation. 
 
 1. Correction of the Refractive Error 
 is of the greatest importance, and ^°- ^^''^^^'^ ^"'""^ 
 frequently is curative. In esophoria 
 
 the full and constant correction of hyperopia and astigma- 
 tism is indicated, and sometimes an under-correction of 
 myopia. In exophoria, a partial correction of the hyperopia, 
 so as to favor accommodation and divergence, and a full cor- 
 rection of myopia are often advisable; and such glasses are 
 to be worn constantly, if possible. 
 
 2. Attention to the General Health is a necessary and valu- 
 able adjunct to local treatment. Tonics (especially strych- 
 nine), hygienic improvement, regulation of habits, and partic- 
 ularly plenty of outdoor exercise are indicated, especially in 
 neurasthenic and delicate individuals. 
 
 3. Prism Exercises strengthen adduction and abduction: 
 In exophoria, prisms with bases out are supported before the 
 
 patient's eyes, and he is directed to look at a lighted candle, 
 placed 20 feet distant. As soon as the double images come 
 together, the prisms are lifted, and after a rest of a few sec- 
 onds they are replaced. Commencing with 5°, the strength 
 of the prisms is increased every few days, until the patient 
 can easily fuse the double images produced by a pair of 20° 
 prisms. The exercises are continued for a few minutes, sev- 
 eral times a day. Whenever there is difficulty in bringing the 
 double images together, the patient must approach the light 
 until the fusion is easily accomphshed, and then gradually in- 
 crease the distance from the candle. 
 
390 DISTURBANCES OF MOTILITY OF THE EYE 
 
 In esophoria, if symptoms persist after suitable correction of 
 the error of refraction, prism exercises, bases in, may be tried; 
 they offer less chance of success than in exophoria. 
 
 In hyperphoria, prism exercises, base down or up, are some- 
 times beneficial. 
 
 4. The Wearing of Prisms is indicated if correction of the 
 refractive error, improvement in general health, and ocular 
 muscle exercises have failed to reUeve the symptoms. The 
 strength of the prisms prescribed should correspond, as a gen- 
 eral rule, to about half the deviation, though sometimes a full 
 correction gives comfort. The wearing of prisms does not 
 correct the deviation, but may remove the discomfort. Only 
 weak prisms can be worn, since those of greater strength than 
 5 ° are uncomfortable. In exophoria the bases are turned in, 
 in esophoria out, in hyperphoria up or down. The wearing of 
 prisms is frequently unsatisfactory and the relief is often merely 
 temporary. Such correction should not be continued for too 
 long a time, since it usually causes an increase in the deviation. 
 
 If glasses are worn, the effect of a prism may be obtained by 
 decentering — that is, displacing the optical centre so that it no 
 longer corresponds to the geometrical centre of the lens (Figs. 
 365 and 366). Decentering a convex lens in, or a concave lens 
 out, produces the effect of a prism with its base toward the nose; 
 decentering a convex lens up or a concave lens down gives the 
 effect of a prism with its base up. A lens of 1 D. must be de- 
 
 FiG. 365. Fig. 366. 
 
 Fig. 365. — ^The Prismatic Effect of Decentering a Convex Lens. A, Convex lens 
 
 decentered downward; B^ optical centre corresponds to geometrical centre. 
 Fig. 366. — ^The Prismatic Effect of Decentering a Concave Lens. A, Concave lens 
 
 decentered downward; B, optical centre corresponds to geometrical centre. 
 
 centered 8.7 mm. to produce the effect of a prism of 1 °. To 
 calculate the amount of decentering necessary to produce a 
 certain prismatic effect, we multiply 8.7 by the value of the 
 
OPERATION FOR HETEROPHORIA 391 
 
 prism, and divide the result by the strength of the lens in diop- 
 ters. For example, a + 4 D. lens O prism of 2 °, base in, 
 equals —^ = 4.3 mm.; such a lens should be decentered 
 inward 4.3 nam. in order to have the added effect of a prism 
 of 2° base in. 
 
 5. Operation should be resorted to only as a last resort, after 
 all other measures have been tried and the affection continues 
 troublesome, because we can never be sure of the result; dis- 
 appointment often follows, and occasionally an aggravation of 
 symptoms with added and annoying diplopia. As a general 
 rule, operation is contraindicated imless the deviation is con- 
 siderable, and unless the wearing of prisms has seemed to 
 prove the dependence of the s5Tnptoms upon the heterophoria. 
 A limited or partial tenotomy may be done upon one or both 
 muscles which seem to overact, or a limited or partial advance- 
 ment upon one or both antagonists; the latter operation is 
 less apt to prove disappointing and mischievous, and is, con- 
 sequently, the safer. 
 
 Partial Tenotomy and Partial Advancement. — In these op- 
 erations a small opening is made into the conjunctiva over the 
 insertion of the tendon. In tenotomy, the central portion of 
 the tendon is seized and cut, and this incision extended toward 
 both borders, leaving the peripheral portions intact; the effect 
 is measured after each cutting, until the result is sufficient. In 
 advancement, the central portion of the tendon is dissected 
 from the eyeball and stitched forward. The instruments used 
 resemble those employed for ordinary tenotomies and ad- 
 vancements, but are of more dehcate construction. These 
 operations, though practised quite frequently and occasion- 
 ally followed by brilliant results, are criticised unfavorably by 
 the majority of competent oculists; the effect is uncertain, and 
 the operation must often be repeated a, number of times before 
 a decided result is obtained; before resorting to such operative 
 procedures, we ought to be certain that other means have 
 proven unsuccessful. 
 
 NYSTAGMUS 
 
 Nystagmus is a; short, rapid, involuntary oscillation of the 
 eyeball, usually affecting both eyes and associated with imper- 
 
392 DISTURBANCES OF MOTILITY OP THE EYE 
 
 fed, vision; it may be congenital or acquired. The movements 
 are most frequently from side to side {lateral nystagmus) or 
 around the antero-posterior axis {rotatory nystagmus), some- 
 times up and down {vertical nystagmus). There may be a 
 combination of the lateral or vertical with the rotatory move- 
 ments {mixed nystagmus). The oscillations are similar in 
 kind, duration, and frequency in the two eyes. They may be 
 constant or present or exaggerated only when the eyes are 
 turned in certain directions. The patient is not, as a rule, irv- 
 convenienced by the existence of this condition; but when it 
 commences in adult life there may be much annoyance from 
 the apparent movements of objects. 
 
 Most cases exist from infancy, and depend upon diminution 
 in the acuteness of vision or amblyopia as a result of opacities 
 of the media, intraocular diseases, albinism and other con- 
 genital anomalies, and very marked errors of refraction; in 
 such instances the affection is due to defective vision, which 
 prevents the infant or child from learning to fix properly. 
 
 In adults it may develop with many cerebral affections, espe- 
 cially disseminated sclerosis, disease of the cerebellmn, and 
 Friedreich's disease. It is found in miners {miner's nystag- 
 mus); in these cases it is due to defective illumination and 
 strain and exhaustion of the ocular muscles, because the eyes 
 must be turned in uimatural directions, especially when pre- 
 disposed by errors of refraction. It occm-s also in labyrin- 
 thine irritation and disease {labyrinthine nystagmus). 
 
 The usual infantile cases are not amenable to treatment, 
 though the condition sometimes becomes less marked with ad- 
 vancing years; the correction of errors of refraction may be of 
 some benefit. Miner's nystagmus generally disappears when 
 the patient gives up this kind of work, and the labyrinthine 
 variety ceases after the cause has been removed. 
 
CHAPTER XXVI 
 
 OCULAR THERAPEUTICS 
 GENERAL RULES FOR EYE OPERATIONS 
 
 The eye being a very delicate and sensitive organ, it be- 
 comes necessary, in applying various therapeutic resources, to 
 limit the strength of local applications and to observe care in 
 the manner in which such remedies are applied. 
 
 Remedies employed in the treatment of diseases of the eye 
 may be divided into 1. constitutional, and 2. local. 
 
 Constitutional Remedies are frequently prescribed and 
 often exercise a marked influence on the progress of ocular 
 disease. Many systemic disorders present ocular manifesta- 
 tions; and an important part of the treatment of the latter 
 consists in general medication intended to correct the con- 
 stitutional disturbance. Syphilis, tuberculosis, anssmia, and 
 other disordered states give rise to well-marked eye symptoms 
 and diseases, which will yield only after proper internal treat- 
 ment. Some ocular diseases are dependent upon a lowering of 
 the general health, for which tonics are indicated. Rest in bed 
 is often absolutely necessary for the effective control of some 
 of the acute affections of the deeper structures of the eye. 
 Thus it is evident that the condition of the system cannot be 
 disregarded in the treatment of ocular diseases. 
 
 Local Remedies. — Drugs intended for local use to the eye 
 are most frequently dissolved in water; a saturated solution of 
 boric acid forms a very good menstruum. Such remedies are 
 also used in oily, ointment, powder, or solid form. 
 
 CLEANSING AND ANTISEPTIC SOLUTIONS 
 
 Solutions of this sort are employed for flushing the conjunc- 
 tival sac and removing secretion. They are used freely, are 
 bland and unirritating, and should be lukewarm. They are 
 allowed to run between the lids from a wad of absorbent cotton, 
 
 393 
 
394 
 
 OCULAR THERAPEUTICS 
 
 Fig. 367.— Undine for Irrigat- 
 ing the Eye. 
 
 from an eye-dropper (using 2 or 3 dropperf uls) , or poured out 
 very conveniently by means of tlie undine (Figs. 367 and 369), 
 or with a soft-rubber bulb syringe 
 (Fig. 368). 
 
 The eye-cup is very popular for this 
 purpose; before use, the edges of the 
 lids should be cleansed; otherwise the 
 fluid will become contaminated with 
 dust adhering to the lashes and in- 
 troduce this into the conjunctival 
 sac. 
 
 The cleansing and antiseptic solu- 
 tions which are used most frequently 
 are: 
 
 1. Boric Acid in saturated solution 
 (about 4 per cent.; 3ss. of the crystals to i. 
 
 2. Sodium Chloride in physiological strength (0.6 per cent.; 
 3i to Oi.). 
 
 3. Mercuric Chloride, from 1 : 10,000 to 
 1 : 6,000; gr. i. to i. 
 
 The following will be found useful when a 
 bland and cleansing solution is required : 
 
 R Sodii bicarb . . gr. x. I^ Ac. boric gi"- x. 
 
 Sodii bibor ... gr. x. Sod. bibor . . . gr.xv. 
 
 Aq. camphor . oi. Glycerin 5i- 
 
 Aq. destill . . . giv. Aq. destill . . . giv. 
 
 M. S. Eye wash. M. S. Eye wash. ,, „„„ 
 
 ■' . ■' Fig. 368. — Soft- 
 
 Rubber Eye Syringe. 
 
 Boric Acid (boracic acid) is used more fre- 
 quently than any other of these remedies. Though chemically 
 an acid, its solution is bland and soothing and is often em- 
 ployed for irrigation. It is frequently prescribed with white 
 vaseline, cold cream, or lanolin, in the form of an ointment, to 
 prevent adhesion of the lids overnight, when there is con- 
 siderable discharge. 
 
 ^ Acidi borici gr. iij. 
 
 Vaselini albi 3 ij- 
 
 M. ft. ungt. 
 
 R Acidi borici gi-. iij. 
 
 Ungt. aq. rosae 3 ij- 
 
 M. ft. ungt. 
 
ASTRINGENT AND STIMULATING SOLUTIONS 395 
 
 STIMULATING AND ASTRINGENT REMEDIES 
 
 The remedies of this class used most frequently are: Zinc 
 sulphate, tannic acid, alum, borax, thiosinamine, camphor, 
 silver nitrate, copper sul- 
 phate, yellow oxide of 
 mercury, ammoniated 
 mercury, calomel, and 
 ichthyol. Thej' are in- 
 tended to cure abnormal 
 conditions of the con- 
 junctiva, and are used 
 principally in various 
 forms of conjunctivitis. 
 For this purpose they 
 are prescribed in small 
 quantity. Two or 3 drops 
 are allowed to fall upon 
 the everted lower lid 
 from an eye - dropper 
 (Fig. 370); the latter 
 
 must not touch the lids or lashes, since such contamination 
 would infect the liquid contained in the bottle to which the 
 dropper is returned. Most of these remedies are used in 
 ivatery solution; copper sulphate and alum are frequently em- 
 ployed in solid form. 
 
 Zinc Sulphate is used very often in astringent collyria. 
 
 Fig. 369. — Method of Irrigating the Eye with a 
 Solution Poured from an Undine. 
 
 I^ Zinci sulph gr. i. 
 
 Aquae destill 5 i. 
 
 M. S. Two drops in each eye three 
 
 times a day. 
 
 I^ Zinci sulph gr. i. 
 
 Acidi borici gr- v. 
 
 Glycerini 5 ss. 
 
 AquiE destill § i. 
 
 M. S. Eye drops. 
 
 I^ Zinci sulph gr. i. 
 
 Acidi borici gr. v. 
 
 Aquae destill § i. 
 
 M. S. Eye drops. 
 
 I^ Zinci sulph gr. i. 
 
 Aquae camphor TU x. 
 
 Aquaj destill § i. 
 
 M. S. Two drops in each eye twice 
 
 a day. 
 
 Tannic Acid is frequently used in combination with other 
 astringents. It is often dissolved m glycerin, and solutions of 
 
396 
 
 OCULAR THERAPEUTICS 
 
 5 to 25 per cent, are painted on the everted lids in 
 trachoma. 
 
 I^ Acidi tannioi gr. ss. 
 
 Zinci sulph gi-. ss. 
 
 Aqiuf destill §1. 
 
 M. S. Two drops in each eye two 
 
 or three times a day. 
 
 I^ Acidi tannici gr. ss. 
 
 Acidi borici gr. v. 
 
 Aqua; destill § i. 
 
 M. S. Two drops in each eye two 
 
 or three times a dav. 
 
 ;-i. to o i .) . Long-continued use is said to inj ure 
 The stick of alum is applied to the everted 
 
 Alum (gr. 
 the cornea. 
 
 lids in chronic conjunctivitis, and in mild forms of trachoma. 
 
 Borax is used as a cleans- 
 ing wash ( 5i. to O i.), or in 
 combination with other rem- 
 edies : 
 
 I^ Zinci sulph gr. ss. 
 
 Sodii biborat gr. iij. 
 
 Aquae destill 5 '• 
 
 M. S. Two drops in each eye two 
 or tlii'ee times a day. 
 
 I^ Acidi tannici gr. J^ 
 
 Sodii biborat gi"- iij- 
 
 Aquae camphor 5 ij- 
 
 Aquae destill 5 vi. 
 
 M. S. Eye drops. 
 
 Thiosinamine is used in 10 
 p. c. ointment, with massage, 
 
 Fig. 370.— Method of Instilling Drops by . . 
 
 Means of an Eye-Dropper. tO TCduCe COmeal Opacities. 
 
 Camphor. — Though feebly 
 soluble in water, such solution (aqua camphorse) is stimulat- 
 ing and astringent, and is often incorporated in collyria. 
 
 Silver Nitrate, always dissolved in ditiliUed water, may be 
 used in the strength of gr. jjjto gr. g to 5 i., dropped into the 
 conjunctival sac. In stronger solution (gr. i. — v. to 5 i.) it is 
 hniKhcd u])on the everted lidn, in various forms of conjuncti- 
 vitis. Solutions of silver nitrate spoil upon contact with or- 
 ganic matter; the l)rush or cotton applicator should not be 
 dipped into the bottle, but some of the solution should be 
 
STIMULATING AND ASTRINGENT REMEDIES 397 
 
 poured into a small vessel for each use. Silver solutions, when 
 used repeatedly and frequently, may permanently stain the 
 conjunctiva (argyrosis); hence they should be applied by the 
 physician himself, and only for a limited period. When stronger 
 than 1 per cent., they act as disinfectants and caustics (p. 399). 
 
 Copper Sulphate (" bluestone ") may be employed in solu- 
 tion (gr. i. to 5 i.) ; but its chief use is in the form of the crystal. 
 A flattened pencil (Figs. 127 and 129) is rubbed across the 
 everted lids in trachoma, and the excess washed off with water; 
 the pencil should be flattened and have a blunt, rounded 
 extremity (p. 120). 
 
 Yellow Oxide of Mercixry, insoluble in water, is employed in 
 an ointment made with white vaseline, cold cream, or lanoUn 
 (1 to 2 per cent.), which must be thoroughly mixed and pre- 
 served in a jar coated externally with asphalt varnish so as to 
 be impervious to light. 
 
 I^ Hydrarg. oxidi flavi . . . gr. i. I^ Hydrarg. oxidi flavi. . . . gr. ij. 
 
 Vaselini albi 3 iJ- Ungt. aquse rosae • 3 ij- 
 
 M. ft. ungt. S. Eye salve. M. ft. ungt. S. Eye salve. 
 
 These ointments are often prescribed in blepharitis, chronic 
 conjunctivitis, phlyctenular keratitis and conjunctivitis, inter- 
 stitial keratitis, and opacities of the cornea. In blepharitis the 
 ointment is rubbed into the margin of the lid, after removal of 
 scales or crusts; in other affections, a small piece is transferred 
 from a glass rod or cotton-tipped applicator or tooth-pick, to 
 the everted lower lid, and thus into the conjunctival sac. 
 
 Ammoniated Mercury, a white, insoluble powder, is pre- 
 scribed in the same strength and under the same circum- 
 stances as the yellow oxide of mercury. 
 
 Calomel, in the form of a fine powder, is dusted into the eye 
 with a camel's-hair brush, or from cotton wound upon an 
 applicator, in phlyctenular keratitis and corneal ulcers; it is be- 
 lieved to be slowly changed to corrosive sublimate by contact 
 with the tears, and thus to keep the eye bathed in an antisep- 
 tic fluid; calomel should not be used if the patient is taking 
 iodine, since such a combination produces the very irritating 
 mercuric iodide in the tears. 
 
398 OCULAR THERAPEUTICS 
 
 Ichthyol in 5 or 10 per cent, ointment forms an excellent 
 application for obstinate examples of ulcerative blepharitis. 
 
 ^ Ichthyol gr. vi. I^ Ichthyol gr. x. 
 
 Vaselini 5 ij. Ungt. zinci ox 3 ij- 
 
 M. ft. ungt. S. Apply to edges M. ft. ungt. S. Apply to edges 
 
 of Uds after cleansing. of hds after cleansing. 
 
 Lead Acetate should not be employed since it deposits an in- 
 soluble salt of lead upon any corneal abrasion; this stain can- 
 not be removed. Lead and opium wash is not, therefore, a 
 desirable application for the eye. 
 
 DISINFECTANTS AND CAUTEBANTS 
 
 True disinfectants (capable of destroying germs) cannot be 
 instilled into the conjimctival sac under ordinary circum- 
 stances without injury to the cornea; they are, however, ap- 
 plied to circumscribed areas, the excess being washed off by 
 water. Corneal ulcers, especially when infected, and purulent 
 conjunctivitis furnish common indications for such use. Some 
 of the remedies classified under this head, though not, strictly 
 speaking, true disinfectants in the strength used, have an in- 
 hibitory action upon the growth of micro-organisms and thus 
 act as practical disinfectants. Those used most commonly in 
 connection with the eye are: mercuric chloride, chlorine 
 water, potassium permanganate, carbolic acid, formalin, 
 tincture of iodine, silver nitrate, argyrol, protargol, iodoform, 
 ethyl hydrocuprein, and the cautery. 
 
 Mercuric Chloride (Corrosive Sublimate) is often pre- 
 scribed in purulent and other forms of conjunctivitis. It may 
 safely be used 1: 5,000; when stronger, it injures the cornea, 
 and must consequently be limited to the everted lids, and the 
 excess carefully washed off. A strong solution, 1:500, is 
 rubbed into the conjunctiva in the final stage of the operative 
 expression of trachoma. Solutions of corrosive sublimate are 
 often used to flush the eye during operations; they attack the 
 metal of instruments and dull the cutting edges. 
 
 Corrosive sublimate is frequently used in 1:3,000 ointment 
 (often known as White's ointment) made up as follows : 
 
DISINFECTANTS AND CAUTERANTS 399 
 
 IJ Hydrarg. bichlor gr. ^ 
 
 Sodii Chlor gr. | 
 
 Alcohol dil q.s. 
 
 Petrolati albi 5 i. 
 
 Dissolve sublimate and salt in a few drops of dilute alcohol and mix 
 with the vaseline, which has previously been kept at a temperature of 
 212° F. for half an hour. Stir until cool. 
 
 This salve is bland, antiseptic, and very useful in various 
 forms of conjunctivitis, ulcers of the cornea, phlyctenular 
 affections, serving to keep the conjunctival sac filled with a 
 weak disinfectant and to prevent adhesion of the lid margins 
 overnight; some operators put a little in the conjunctival 
 sac after cataract extraction and other operations upon 
 the globe. 
 
 Chlorine Water (freshly prepared) diluted with 10 to 20 parts 
 of water is sometimes employed in purulent conjunctivitis. 
 
 Potassium Permanganate in 1 : 5,000, or stronger, aqueous 
 solution is used for irrigation in purulent conjunctivitis. 
 
 Carbolic Acid (3-per-cent. solution) is used only for disin- 
 fecting instruments. The pure acid is sometimes applied to 
 infected ulcers of the cornea. 
 
 Formalin. — Solutions of 1:1,000 and 1:2,000 are used in 
 purulent conjunctivitis; solutions of 1: 500 are applied to in- 
 fected ulcers; solutions of 1 : 200, and formalin vapor, are 
 sometimes employed for the disinfection of instruments. 
 
 Tincture of Iodine is an excellent remedy in the treatment 
 of infected ulcers (p. 143). 
 
 Silver Nitrate is a very efficient and popular disinfectant. 
 In 1 or 2 per cent, solution it is brushed upon the everted lids 
 in purulent and other forms of conjunctivitis, and the excess 
 washed off. In 2-per-cent. solution, one drop is instilled into 
 the eyes of the new-born as a prophylactic measure against 
 ophthalmia neonatorum. In stronger solution, and in solid 
 stick, it is applied to infected and indolent ulcers and the excess 
 neutralized by salt solution. Fused with potassium nitrate in 
 various proportions, it forms the "mitigated stick." For local 
 anaesthesia preliminary to silver applications, nitrate of cocaine 
 should be used instead of the customary muriate, since the 
 latter is incompatible and precipitates chloride of silver. 
 
400 OCULAR THERAPEUTICS 
 
 Iodoform is a feeble disinfectant which is sometimes dusted 
 upon corneal ulcers, or used in 2 to 4 per cent, ointment in such 
 lesions. It is not infrequently dusted upon wounds after 
 plastic operations upon the lids. Nosophen is an efficient and 
 odorless substitute for iodoform. 
 
 Arg3rrol, an organic salt of silver, soluble in water, forming a 
 brown solution, is used in 5 to 25 per cent, solution in the same 
 class of cases in which silver nitrate is indicated; it is penetrat- 
 ing, is not precipitated by fluids containing sodium chloride and 
 albumen, and is devoid oj the irritating qualities of silver nitrate; 
 it has the same tendency to stain the conjvmctiva, when used 
 for a considerable period, which is observed with silver nitrate, 
 and may also leave a brown discoloration upon the cornea 
 when ulceration exists; its germicidal effect is very limited. 
 
 Protargol (2 to 10 per cent.) has identical properties and 
 uses as argyrol with greater germicidal action, but produces 
 more irritation. 
 
 Ethyl Hydrocuprein (Optochin), a derivative of quinine, 
 is a specific for pneumococcus ulcer, in 1-per-cent. sol. or salve. 
 
 The Electro-Cautery (p. 143) gives us the most certain 
 means of limiting the spread of corneal ulcers, by destroying 
 the infecting micro-organisms. It is also used in conical 
 cornea, and in epithelioma of the lid. 
 
 MYDBIATICS AND CYCLOFLEGICS 
 
 Mydriatics are remedies which produce dilatation of the 
 pupil; cycloplegics are agents which cause paralysis of the 
 ciliary muscle (accommodation). Practically, these two 
 terms are interchangeable, since, with two exceptions, mydri- 
 atics also produce paralysis of the ciliary muscle. The drugs 
 commonly employed to induce mydriasis and cycloplegia are 
 atropine and homatropine; much less frequently duboisine, 
 daturine, hyoscyamine, and scopolamine. The remedies used 
 to dilate the pupil, without action on the ciliary muscle, are 
 cocaine and euphthalmin. 
 
 Indications. — These agents are used (1) in iritis, to dilate 
 the pupil, prevent adhesions, and exert a sedative action; (2) 
 in various diseases of the cornea and of the deeper structures; 
 
MYDRIATICS AND CYCLOPLEGICS 401 
 
 (3) after certain operations; (4) to paralyze accommodation in 
 estimating the state of refraction; (5) to dilate the pupil for 
 ophthalmoscopic examination; and (6) to enlarge the pupil in 
 lamellar and nuclear cataract. 
 
 Atropine, the alkaloid of Belladonna, the most commonly 
 employed mydriatic, is prescribed in the form of sulphate in 
 solutions varying from | to 2 per cent, (most often 1 per cent.) ; 
 occasionally in ointment or oil. 
 
 IJ Atropin. sulphat gr. i. I^ Atropin. sulphat gr. i. 
 
 Aquae destill 5 ij. Cocain. hydrochlor. . . . gr. ij. 
 
 M. S. Poison. One drop in each Aquse destiU 5 Jj- 
 
 eye every four hours. M. S. Poison. 
 
 Atropine paralyzes the sphincter of the pupil and stimulates 
 the dilator. After instillation of 2 or 3 drops at intervals of 10 
 minutes, pronounced action will have taken place in half an 
 hour after the last dose; the effects last a week. Atropine and 
 other mydriatics (except, generally, cocaine and euphthalmin) 
 increase intraocular tension. They are contraindicated in glau- 
 coma, and in persons who have a tendency to this disease; we 
 should carefully test the tension in persons past middle life 
 before instilling atropine. 
 
 Atropine Poisoning. — In susceptible individuals atropine 
 may cause general toxic symptoms: Dryness of the throat, 
 flushing of the face, headache, vomiting, quick pulse, cutane- 
 ous eruption, excitability, and even delirium; the antidote is 
 morphine. In persons who show such an idiosyncrasy, or . 
 when we wish to push the remedy, it is well to have the pa- 
 tient press the finger against the lacrymal sac for several 
 minutes after each instillation. When the susceptibility is 
 very great, one of the other mydriatics (mentioned below) 
 may be resorted to, or we may use a 10-per-cent. solution of 
 aqueous extract of belladonna in water ; ophthalmic discs, which 
 contain very small doses, may prove useful in such cases. 
 
 Atropine Irritation, — In some persons, when long contin- 
 ued, atropine may cause considerable local irritation, showing 
 itself in congestion, oedema, and eczema of the lids, and follic- 
 ular conjunctivitis. 
 When using atropine or other solutions for the local effects 
 
402 OCULAR THERAPEUTICS 
 
 upon the cornea or deeper parts, the drop is allowed to fall 
 upon the cornea or into the lower conjunctival sac, the, upper 
 lid being raised and the patient directed to throw the head 
 back and to look down (Fig. 370). Such solutions are pre- 
 scribed in small quantities ( 3ij-) and labelled "Poison." 
 
 Duboisine Sulphate (gr. | to 3ij.), Daturine Sulphate (gr. 
 J to 5ij-)) Hyoscyamine Hydrobromate (gr. 5 to 3ij-)) and 
 Scopolamine Hydrobromate (gr. | to 3ij-)) occasionally suh- 
 stitvied for atropine, have similar attributes, are contraindi- 
 cated in increased tension, and may also produce poisoning. 
 
 Homatropine Hydrobromate resembles atropine in its ac- 
 tion, but is milder. It is extensively used to paralyze accom- 
 modation during the examination for errors of refraction. 
 Though this effect is not so perfect as with atropine, it is suffi- 
 cient for all practical purposes, and lasts only 24 or 36 hours; 
 if, after the examination, 2 drops of a |-per-cent. solution of 
 eserine be instilled, the effects of homatropine will be neutral- 
 ized within 2 hours. For refraction cases, it is usually used in 
 2-per-cent. solution, one drop being instilled every few minutes 
 for 4 doses; 50 minutes after the final dose, the eye will be 
 ready for examination. Homatropine is frequently com- 
 bined with cocaine for this purpose: 
 
 I^ Homatropin. hydro- I^ Cocain. hydrochlor gr. i. 
 
 brom gr. i. Homatropin. hydrobrom. gr. ij. 
 
 Aquae destill 3 i- Aquae destill 3 ij- 
 
 M. S. Poison. M. S. Poison. 
 
 Euphthalmine is very useful for dilating the pupil for oph- 
 thalmoscopic examination; 1 or 2 drops of a 5-per-cent. solution 
 cause mydriasis in 30 minutes, and the effects pass off within 
 2 hours; it has but a feeble action upon accommodation, and 
 rarely causes increase in tension. 
 
 Cocaine Hydrochloride is frequently used to produce mod- 
 erate dilatation of the pupil for ophthalmoscopic examination. 
 One or 2 drops of a 4-per-cent. solution cause sufficient dilata- 
 tion in 30 minutes, produce insignificant interference with ac- 
 commodation, and the effects disappear within an hour. 
 Cocaine acts by constricting the blood-vessels of the iris; it 
 
MIOTICS 403 
 
 usually diminishes tension. It is sometimes combined with 
 other mydriatics, and then increases the action of the latter. 
 
 MIOTICS 
 
 Miotics diminish the size of the pupil, producing tonic con- 
 traction of the sphincter and of the ciliary muscle, and reduc- 
 ing intraocular tension. These agents are employed chiefly 
 in glaucoma; sometimes in ulcers of the cornea, especially 
 when peripheral. Eserine (| to \ per cent.) and pilocarpine 
 (§ to 2 per cent.) are prescribed; the former is stronger and has 
 a tendency to produce conjunctival irritation and iritis; the 
 latter is milder and free from these drawbacks. 
 
 I^ Eserin. salicylat gr.| — J. I^ Pilocarpin. muriat. . gr.ss. — ij. 
 
 Aquae destill Sij. Aquse destill 3 ij. 
 
 M. S. Poison. M. S. Poison. 
 
 LOCAL ANAESTHETICS 
 
 Cocaine Hydrochloride, in 2 to 4 per cent, solution, is the 
 most commonly employed remedy for producing local anaes- 
 thesia of the conjunctiva, cornea, and to a certain extent the 
 iris, during operations upon the eye; it is also used subcutane- 
 ously and subconjunctivally, with due regard for its poisonous 
 qualities. It serves as a temporary anodyne in corneal and 
 iritic affections, and as a mydriatic for ophthalmoscopic ex- 
 aminations. Combined with atropine and homatropine, it 
 enhances the mydriatic action of these agents. Cocaine pro- 
 duces dilatation of the blood-vessels, after a preliminary con- 
 traction, and lowers intraocular tension; it has a tendency to 
 cause desiccation with desquamation of the corneal epithelium; 
 hence after instillation the patient should be directed to keep 
 the lids closed; for the same reason it should not be used for 
 any length of time, and it is generally unwise to prescribe 
 cocaine for home use. 
 
 One drop of 4-per-cent. solution with a second drop after a 
 few minutes, is sufficient to anaesthetize the cornea for the 
 removal of foreign bodies; for more penetrating effects, the 
 instillations are repeated 3 or 4 times, at intervals of 2 min- 
 utes. Solutions of cocaine do not keep well, and should be 
 freshly prepared for operations. 
 
404 OCULAR THERAPEUTICS 
 
 Holocain Hydrochloride is an excellent local anaesthetic, 
 manufactured synthetically, which has supplanted cocaine 
 with many oculists; it is usually employed in 1-per-cent. solu- 
 tion. Its advantages over cocaine are: it is more penetrating, 
 does not dilate the pupil, has no injurious effect upon the cor- 
 nea, and its solution is mildly antiseptic and does not spoil; 
 there is, however, more preliminary conjunctival irritation 
 and, though perfectly safe for instillation, it cannot be vsed 
 hypodermically, since it causes toxic symptoms when em- 
 ployed in this way. 
 
 Alypin, another synthetically-prepared agent, has the same 
 advantages which holocain possesses over cocaine, and in ad- 
 dition is decidedly less poisonous; it is used in 3-per-cent. 
 solution chiefly for minor operations and hypodermically. 
 
 Novocain, eucaine B, tropacocain, acoin, and stovain are 
 other substitutes for cocaine and holocain. 
 
 OTHER THERAPEUTIC MEAStJRES 
 
 Adrenalin (Suprarenin), the active principle of the supra- 
 renal gland, available in 1 : 1,000 aqueous solution of the chlor- 
 ide which can be diluted with salt solution, is a valuable 
 astringent and hcemostatic. After instillation of solutions vary- 
 ing from 1: 10,000 to 1: 1,000, blanching of the conjunctiva 
 occurs as a result of contraction of the blood-vessels, begin- 
 ning in a minute and lasting half an hour. When the ocular 
 structures are much congested, cocaine and holocain produce 
 unsatisfactory anaesthesia; if combined with adrenalin, these 
 agents act better. Adrenalin is used in some cases of con- 
 junctivitis with marked congestion, in affections of the lacry- 
 mal passages to facilitate expression of retained contents and 
 the introduction of probes, in glaucoma, in congested condi- 
 tions in general, and in operations upon the eye to prevent 
 bleeding and to improve the action of local anaesthetics. 
 
 Dionin, a derivative of morphine, is an analgesic. It is used 
 in iritis and iridocyclitis, glaucoma, keratitis, and scleritis; 
 also for the absorption of pupillary exudates and corneal opac- 
 ities. This remedy is not a local anaesthetic, but it relieves 
 deep-seated pain, acting as a vasodilator and lymphagogue, 
 
VARIOUS THERAPEUTIC MEASURES 405 
 
 stimulating the vascular and lymphatic circulation of the eye 
 and producing marked dilatation of these vessels. It is em- 
 ployed in 2 to 10 per cent, aqueous solution, occasionally in 
 powder or ointment form; after instillation there is marked 
 chemosis and often swelling of the lids; the appearance of the 
 eye is occasionally alarming, but there is no danger of serious 
 consequences. Tolerance for the drug is established very 
 rapidly and then the eye fails to react; hence we must increase 
 the strength of the solution every few days or else intermit 
 from time to time. 
 
 Subconjunctival Injections are employed in episcleritis, 
 scleritis, iridocyclitis, choroiditis, keratitis, corneal ulcer, and 
 in detachment of the retina. After holocainization, the con- 
 junctiva about 10 mm. from the limbus is lifted up and punc- 
 tured by the needle of a hypodermic syringe; from 5 to 15 
 minims of fluid are injected under this membrane, the patient 
 looking downward or upward so as to facilitate the operation. 
 Various germicides — mercury bichloride 1 : 5,000-1 : 1,000, 
 mercury cyanide 1 : 5,000-1 : 1,000, cinnamic acid (hetol) 
 1 : 100— are used and 1-per-cent. acoin often added to reduce 
 the pain; but a solution of sodium chloride of physiological 
 strength is equally effective and much less painful. 
 
 Fluorescein, an orange-red powder, is used in 2-per-cent. 
 aqueous solution (with sodium bicarbonate, 3 per cent, 
 added) to detect abrasions, infiltrations, and ulcers of the cor- 
 nea and to define the limits of such lesions. A drop of the 
 solution is instilled into the conjunctival sac and after a 
 minute the excess is washed off with water; a green stain 
 indicates loss or disease of corneal epithelium. 
 
 Local Bloodletting is of great benefit in affections of the 
 deeper structures of the eye, especially in iritis and iridocy- 
 clitis, and sometimes in acute glaucoma. Leeches are fre- 
 quently prescribed; from two to four are applied to the 
 temple, midway between the outer canthus and the tragus. 
 Occasionally blood is taken from the mastoid region in cases 
 of papillitis. The artificial leech (Fig. 168) is sometimes used 
 as a substitute. 
 
 Salvarsan (or Neosalvarsan) is often used intravenously in 
 
406 OCULAR THERAPEUTICS 
 
 sj^jhilitic ocular affections. The results in iritis are brilliant 
 and in sympathetic ophthalmitis very encouraging; in other 
 diseases (choroiditis, retinitis, papillitis, paralysis of external 
 ocular muscles) the effects vary, but in obstinate cases the use 
 of the remedy is advisable; much difference of opinion exists 
 as to its efficacy in interstitial keratitis. It is not used in 
 atrophy of the optic nerve since no benefit has followed; but 
 there is no evidence that salvarsan has a harmful effect upon 
 the eyes or causes blindness even when inflammation or 
 atrophy of the nerve is present. 
 
 Vaccines and Sera are valuable agents in suitable cases of 
 ocular disease. When possible, an autogenous vaccine should 
 be made; when this is impracticable, stock preparations may 
 be used. Gonococcal vaccine gives excellent results in gonor- 
 rhceal iritis, less certain effects in purulent conjunctivitis. 
 Staphylococcal vaccine may be of service in obstinate examples 
 of phlyctenular affections. Autogenous vaccines sometimes 
 initiate a rapid ciu-e of ulcers of the cornea and hordeola, and 
 are occasionally useful in dacryocystitis and post-operative 
 infections. Antitoxin is indispensable in diphtheritic- con- 
 junctivitis, and anti-pneumococcus serum may be of service in 
 the early stages of infected corneal ulcers. Tuberculin is very 
 extensively used in tuberculous eye affections, often with 
 brilliant results. 
 
 Tuberculin is used both for diagnosis and treatment. 
 
 For diagnostic purposes an injection of 1 mgm. of old tuber- 
 culin (T.O.).is given, and then both general and local reactions 
 are looked for; the former manifests itself in a rise of tem- 
 peratiu-e and is of little importance in this connection; the 
 local reaction shows itself in redness and an increase in the 
 ocular manifestations and is a valuable indication of the tuber- 
 culous nature of the affection. If there is no reaction after 
 the first injection, a second (2 mgm.) and if necessary a third 
 (3 mgm.) are given at intervals of 3 days. Von Pirquet's test 
 may be employed but is much less conclusive; the conjunc- 
 tival tuberculin test is no longer used. 
 
 For treatment, new tuberculin (T.R. or B.E.) is usually em- 
 ployed. The initial dose is iosjo mgm.; the injections are 
 
VARIOUS THERAPEUTIC MEASURES 407 
 
 repeated every third day and the dose increased one-quarter 
 or one-third with each injection until it reaches^ mgm., care 
 being taken to avoid a reaction. Tuberculin treatment is 
 used in tuberculous iritis, choroiditis, episcleritis and scleritis; 
 less frequently in phlyctenular affections and rarer forms of 
 ocular tuberculosis. 
 
 Heat. — Hot, moist compresses are prescribed in affections of 
 the cornea, iris, ciliary body, sclera, and orbit; also to hasten 
 the formation of pus and to relieve pain in lacrymal abscess 
 and panophthalmitis. They are applied by means of flannel 
 or lint wrung out of water as hot as can be borne (115°), 
 placed upon the closed lids, and renewed every minute or two. 
 
 Cold. — Cold corn-presses are used in inflammatory affections- 
 of the conjundiva. Strips of lint, lintine, or similar material 
 are folded to make pads of four thicknesses, about 1§ inches 
 square, moistened and cooled upon a block of ice; they are laid 
 upon the closed lids and changed as soon as they become 
 warm. In theabsence of ice,thecompressesmay be wrung out 
 of cold water. Ice should never be applied directly to the lids. 
 
 Electricity is seldom used in ocular therapeutics, except in 
 the form of the electro-cautery for corneal ulcer (p. 143) and 
 conical cornea (p. 153); electrolysis may be employed for the 
 removal of distorted lashes (p. 47) and in xanthoma. The 
 galvanic current is occasionally resorted to in paralyses of oc- 
 ular muscles, optic-nerve atrophy, and corneal opacities, and 
 high-frequency currents in atrophy of the optic nerve. 
 
 The X-Rays and Radium are used with benefit in trachoma, 
 spring catarrh, and epithelioma of the eyelid. Carbon-dioxide 
 snow is recommended for the same affections. 
 
 Massage is sometimes prescribed in interstitial keratitis, 
 glaucoma, and in corneal opacities. A small quantity of oint- 
 ment is placed in the conjunctival sac; then the finger is ap- 
 plied to the closed upper lid, and' the cornea massaged gently 
 for a few minutes at a time. 
 
 Protective Measures of various sorts are applied to the eye 
 to insure rest, to keep out light, air, wind, and dust, and to 
 give support. The patient is sometimes kept in a dark or 
 shaded room during the course of diseases of the uveal tract 
 
408 GENERAL CONSIDERATIONS OF OPERATIONS 
 
 and retina. Various kinds of glasses intended to subdue the 
 light are frequently ordered; the colors generally used are 
 varying shades of smoke, amber, green, and amethyst ; such 
 
 glasses may be either plane or 
 curved (coquilles). Mica 
 spectacles are worn by work- 
 men engaged in stone-cut- 
 ting and similar occupations. 
 Black Patches (Fig. 371) are 
 made use of when imperfect 
 protection is sufficient. The 
 application of eye bandages is 
 described on p. 411 (Figs. 376 
 and 377). 
 
 GENERAL CONSIDERA- 
 TIONS OF OPERATIONS 
 
 The rules of asepsis and 
 antise-psis which govern gen- 
 eral surgery are also indicated 
 in ophthalmic operations, except that strong solutions of ger- 
 micides are not tolerated by the eye. In other respects, the 
 preparations connected with an operation are similar to those 
 employed by the general surgeon. 
 
 Preparation of the Patient. — The patient should enter the 
 hospital 24 hours previous to operation; he should receive a 
 bath and then take a cathartic the night before, followed by 
 an enema on the morning of the operation. He should be in 
 good physical condition; old age, albuminuria,. and diabetes are 
 no contraindications, but such patients require special care. 
 
 It is imperative to examine the conjunctiva and the lacrymal 
 region before deciding to operate upon the eyeball, especially 
 in iridectomy and cataract extraction; the presence of muco- 
 purulent secretion renders such an operation extremely hazar- 
 dous, on account of the danger of infection; in such cases, the 
 conjunctival or lacrymal affection must first be cured by ap- 
 propriate treatment. A cidture of the conjunctival secretion 
 should be made in every case in which an incision into the 
 
 Fig. 371.— Eye-Patch. 
 
PREPARATIONS FOR EYE OPERATIONS 
 
 409 
 
 globe is required; in cases of doubt, it is well to bandage the 
 eye for twenty-four hours, and then to examine the dressing. 
 
 Preparation of the Hands of the Operator comprises thor- 
 ough scnibbing with soap and warm water and immersion in 
 1 : 1,000 sublimate solution or alcohol. Rubber gloves are 
 not worn during eye operations. 
 
 Preparation of Instruments. — Blunt instruments should be 
 boiled in l-per-cent. solution of soda,, rinsed with sterile water, 
 and then kept in a sterile solution of salt (0.6 per cent.), or 
 allowed to dry in sterilized gauze. Sharp instruments should 
 be tested upon thin kid stretched in the testing-drum (Fig. 
 
 Pig. 372. — Drum Used to Test the Cutting Edges of Eye Instruments. 
 
 372). Knives with delicate cutting edges (such as cataract 
 knives, keratomes, knife-needles, and cystotomes) are 
 wiped carefully with benzin, dipped into pure carbolic acid, 
 then into alcohol, held in boiling water for 20 seconds, trans- 
 ferred to alcohol, next to sterile saline solution, and finally 
 allowed to dry; throughout this preparation great care must 
 be taken not to injure the point or edge. 
 
 Position of the Patient. — The patient may be operated 
 upon either in bed or on a table, occasionally upon a special 
 operating-chair (Figs. 373 and 374). Daylight answers very 
 well for the lids and external muscles; but in operations upon 
 the globe, especially cataract extraction, iridectomy, and the 
 like, artificial illumination is preferred, the light being con- 
 densed upon the field of operation by a strong convex lens or 
 better by means of an electric projection lamp. 
 
 Preparation of the Region of Operation. — The eyelids, in- 
 
410 GENERAL CONSIDERATIONS OF OPERATIONS 
 
 eluding the lashes, brow, and the surrounding skin, should be 
 cleansed thoroughly with soap and warm water, and then 
 washed with sublimate solution (1:5,000); sometimes the 
 
 Fig. 373. — The Author's Examining and Fig. 374. — The Same Converted into an 
 Operating Chair. Operating Table. 
 
 lashes are cut close to the lid-margins; some operators prefer 
 to have the eye prepared the day before or the morning of the 
 operation, and then covered by sterile gauze and a bandage, 
 which dressing is not disturbed until the operation. The 
 everted lids, eyeball, and conjunctival sac are flushed with a 
 large quantity of warm saline or boric solution preceding the 
 operation. 
 
 Anaesthesia. — In the great majority of adult cases, local an- 
 iEsthesia is sufficient in operations upon the eyeball: Two 
 drops of 4-per-cent. cocaine or 1-per-cent. holocain are instilled 
 every few minutes for 4 doses, the lids being kept closed in the 
 intervals. 
 
 Subconjimctival injection of a few minims of 4-per-cent. co- 
 caine will render operations upon the globe absolutely pain- 
 less, even to the cutting of the iris. A hypodermic injection 
 of mor-phine half an hour before operation is often useful in 
 allaying nervousness. 
 
 In children, also in enucleations, in glaucoma with very 
 high tension, in blepharoplastic operations, and occasionally 
 in other procedures, a general anae.sthetic is necessary. 
 
ANESTHESIA IN EYE OPERATIONS 
 
 411 
 
 In certain operations upon 
 the lid a l-per-cent. solution 
 of cocaine, or 2-per-cent. no- 
 vocain in 1 : 3,000 adrenalin, 
 may be used hypoder mi colly ; 
 or the infiltration method of 
 Schleich may be utilized, 
 though the cedematous and 
 altered appearance of the lids 
 following this procedure is 
 often objectionable. General 
 anaesthesia is usually resorted 
 to in lid operations. 
 
 Cleansing Solutions. — In 
 the course of operations upon 
 the eyeball, it is necessary to 
 cleanse the seat of operation, 
 and to irrigate the cornea frequently to prevent desiccation. 
 The solutions used for this purpose are horic acid 4 per cent., 
 
 Fig. 375.— Gauze and Absorbent Cotton 
 Dressing Retained by Plaster Strips. 
 
 Fig. 376. — Monocular Bandage. 
 
 Fig. 377. — Binocular Bandage. 
 
 salt 0.6 per cent., and mercuric chloride 1 : 10,000. These solu- 
 tions are applied either by means of an undine (Fig. 367), a 
 
412 GENERAL CONSIDERATIONS OF OPERATIONS 
 
 pipette or eye-dropper, or small wads of absorbent cotton 
 known as " cotton sponges." 
 
 Dressings vary with the nature of the operation. Sterilized 
 gauze and absorbent cotton, used dry or soaked in antiseptic 
 solutions (bichloride 1 : 5,000, or boric 4 per cent.) are gen- 
 erally applied next to the closed eyelids, covered by an addi- 
 tional layer of dry cotton, and retained by a bandage covering 
 one or both eyes, sometimes by strips of isinglass or rubber 
 plaster (Fig. 375). In cataract operations, additional protec- 
 tion from injury is secured by Ring's mask (Fig. 226), wire 
 gauze, or aluminum covers fastened over the dressings. 
 
 Eye Bandages are 1| inches wide, 5 or 7 yards long, and 
 made of gauze, muslin, or flannel. If for protection only, they 
 are applied lightly; if for pressure, they are put on firmly, and 
 care must be taken that the depression between supraorbital 
 margin and nose is properly filled. 
 
 The Monocular Bandage (Fig. 376) is applied as follows: 
 Begin at the temple of the affected eye (right, for example); 
 make one turn around the forehead, pass across the occiput, 
 below the right ear, and obliquely across the right eye; then 
 another turn about the forehead, below the right ear, across 
 the right eye, alternating in this way three or four times. 
 
 The Binocular Bandage (Fig. 377). — Begin at the temple — 
 the right, for example; make a full turn around the forehead 
 and continue to the left temple, then obliquely across the 
 occiput, below the right ear, across the right eye; around the 
 upper occipital region, above the right ear, downward over the 
 left eye, below left ear, across the occiput; below the right ear, 
 across the right eye, and alternate in this manner for three or 
 four turns. 
 
CHAPTER XXVII 
 
 THE OCULAR MANIFESTATIONS OF GENERAL 
 DISEASES 
 
 The ocular symptoms and diseases occurring with general 
 affections, in most instances merely mentioned in this chapter, 
 are discussed more fully in preceding pages, which must be 
 referred to for fuller information on any particular point. 
 
 The systemic diseases which give rise to ocular symptoms 
 and diseases most frequently are syphilis, tuberculosis, rheu- 
 matism, nephritis, diabetes, arteriosclerosis, cardiac affec- 
 tions, diseases of metabolism, chronic intoxications, infective 
 diseases, and affections of the nervous system. 
 
 DISEASES OF THE BLOOD 
 
 Anaemia (Simple) and Chlorosis give rise to pale pink con- 
 junctivae and pearly white sclerce. There may be pallor of 
 the disc and the rest of the fundus, the retinal vessels being 
 pale, tortuous, and the retinal veins broader than normal. 
 Occasionally retinal hemorrhages are found. 
 
 Anaemia (Pernicious) often causes retinal hemorrhages, oc- 
 casionally retinitis. The fundus exhibits great pallor. 
 
 Haemophilia predisposes to profuse hemorrhage after injury 
 to the eye, and under such circumstances may cause hy- 
 phsema, hemorrhage into the retina, or into the orbit. 
 
 Leukaemia. — Retinal hemorrhages are common, and a pecu- 
 liar form of retinitis, "leukcemic reiirdtis," is often present. 
 
 Purpura is often accompanied by hemorrhage beneath the 
 conjunctiva, in the retina, skin of the lids, and occasionally 
 into the orbit. 
 
 Hemorrhage (Severe) may be accompanied by amblyopia, 
 either temporary and accompanied by little or no ophthalmo- 
 scopic change, or permanent and followed by optic-nerve 
 atrophy. Such sudden and severe ansemia may cause retinal 
 hemorrhages. 
 
 413 
 
414 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 DISEASES OF THE CIRCULATORY SYSTEM 
 
 Heart.— Valvular heart disease and fatty heart are often 
 accompanied by hemorrhages into the retina, less frequently into 
 the vitreous. Aortic insufficiency causes pulsation of the re- 
 tinal arteries. Endocarditis may cause embolism of the cen- 
 tral artery of the retina. The oedema dependent upon cardiac 
 disease may involve the eyelids, being noticed especially upon 
 rising in the morning. 
 
 Aorta. — Aneurysm of the aorta may give rise to mydriasis, 
 enlarged palpebral aperture, and exophthalmos as a result of 
 irritation of the cervical sjonpathetic; or to miosis, slight 
 ptosis, and enophthalmos through paralysis of the same; this 
 condition may also cause thrombosis and embolism of the 
 central artery of the retina or of one of its branches. 
 
 Arteriosclerosis gives rise to characteristic changes in the 
 fundus which are described on page 264 and illustrated on 
 Plate XVIII. It is a predisposing cause of glaucoma. 
 
 DISEASES OF THE DIGESTIVE SYSTEM 
 
 Teeth. — The occurrence of ocular symptoms and diseases 
 dependent upon dental disease is not rare, and in such cases it 
 is not uncommon to have the ocular symptoms disappear and 
 the ocular disease improve when the offending tooth is filled or 
 extracted. Such symptoms include conjunctival congestion, 
 photophobia, epiphora, asthenopia, amblyopia, and weakness 
 of accommodation. Iritis, keratitis, cyclitis, and choroiditis 
 may be dependent upon dental disease giving rise to oral sepsis. 
 
 Stomach and Intestines. — Dyspepsia and chronic affections 
 of the stomach and intestines cause ocular symptoms by in- 
 terfering with nutrition and reducing the general tone of the 
 individual; thus we often find asthenopia, weakness of accom- 
 modation, and heterophoria. Absorption of septic matter from 
 the gastro-intestinal tract may give rise to iridocyclitis or 
 choroiditis. The loss of much blood from gastric or intestinal 
 hemorrhage may cause amblyopia with ansemia of the retina 
 without other ophthalmoscopic changes, or with subsequent 
 optic-nerve atrophy. Straining associated with constipation 
 may cause subconjunctival, retinal, and vitreous hemorrhage. 
 
DISEASES OF THE DIGESTIVE SYSTEM 415 
 
 Liver. — Diseases of the liver may cause ocular symptoms 
 such as asthenopia and weakness of accommodation as a re- 
 sult of general loss in strength. \t\ jaundice, the yellowish dis- 
 coloration of sclera and conjunctiva is one of the earliest signs. 
 
 DISEASES OF THE DUCTLESS GLANDS 
 
 Acromegaly exhibits many ocular manifestations. There are 
 hypertrophy of the margins of the orbit and thickening of the 
 skin of the lids. Disease of the hypophysis causes character- 
 istic bitemporal hemianopsia, though other abnormalities of 
 the field of vision are met with, and there is often reduction 
 in the acuteness of vision. There may be optic neuritis and 
 optic-nerve atrophy, and paralysis of one or more of the ocu- 
 lar muscles. Exophthalmos, hypertrophy of the lacrymal gland 
 with epiphora, and sluggish reaction of the pupils are also 
 seen. Pain in the eyes and brow is sometimes complained of. 
 
 Myxoedema and Cretinism give rise to swelling of the eyelids, 
 sometimes optic neuritis with consequent amblyopia, and may 
 be a rare cause of interstitial keratitis. 
 
 Exophthalmic Goitre (Graves' or Basedow's Disease). — 
 Though this is a constitutional disease and the ocular symp- 
 toms are not an essential part, the eye exhibits the most strik- 
 ing manifestations of the affection, some or all of the following 
 occurring in almost every case: 
 
 Exophthalmos is usually present; it varies in degree; it may 
 be slight or the proptosis may be so pronounced that the 
 patient cannot cover the cornea with the lids; it is usually bi- 
 lateral, but occasionally it affects only one eye. Von Graefe's 
 Sign consists in a failure of the upper lid to follow the eyeball 
 normally when the patient looks downward; the upper lid lags 
 behind. Dalrymple's Sign is the name given to the abnormal 
 widening of the palpebral aperture causing the staring look. 
 Stellwag's Sign is the diminution in the normal involuntary 
 power of nictitation as a result of which winking is imperfect, 
 less frequent, and more irregular than normal. Mobius' Sign 
 is the imperfect power of convergence resulting in asthenopic 
 symptoms. Clifford's Sign is the difficulty in everting the 
 upper lid due to retraction and rigidity. 
 
416 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 Vision is not usually involved. The cornea may suffer when 
 exophthalmos is extreme and causes much exposure; in such 
 cases the lower part may become vascular, dry, or ulcerated, 
 and occasionally destruction of the eyeball is the outcome. 
 
 There is a brownish pigmentation of the skin of the lids in 
 some patients. There may be arterial pulsation visible in the 
 fundus. Dilatation and inequality of the pupils may be 
 present. The extrinsic ocular muscles, especially the abdu- 
 cens, may be the seat of paresis. Epiphora is very common. 
 
 DISEASES OF THE EAR 
 
 Choked disc and congestion of the papilla are frequently 
 observed in sinus thrombosis complicating mastoiditis. Nys- 
 tagmus is common and of great diagnostic import in affections 
 
 of the labyrinth. 
 
 INFECTIVE DISEASES 
 
 Cerebrospinal Meningitis is often accompanied by ocular 
 symptoms. Conjunctivitis occurs frequently; oedema of the 
 lids and conjunctiva may be seen. There may be pareses of 
 the extrinsic ocular muscles causing strabismus and ptosis; 
 nystagmus is encountered. There may be abnormalities of 
 the pupils, keratitis, retinal hemorrhage, optic neuritis, and 
 optic-nerve atrophy. Iridochoroiditis, and purulent choroi- 
 ditis, leading to pseudo-glioma, are not uncommon. 
 
 Cholera. — Owing to the shrinkage of orbital tissues the eye- 
 balls are sunken, and the eyes surrounded by bluish circles; 
 the cornea is often dull and sometimes infiltrated or ulcerated; 
 there are subconjunctival, hemorrhages. 
 
 Diphtheria. — With the exception of diphtheritic conjuncti- 
 vitis, which is now rare, the ocular manifestations of diph- 
 theria occur after the acute stage of the disease has passed, 
 and are, therefore, post-diphtheritic symptoms. The latter 
 include paralysis of one or more of the extrinsic muscles of the 
 eye, usually the external rectus, and paralysis of acconamoda- 
 tion. Occasionally optic neuritis occurs. 
 
 Erysipelas, when it spreads to the eye, causes great swelling 
 and redness, so that the lids can be separated only with great 
 difficulty; following this, there may be abscess of the eyelids 
 
INFECTIVE DISEASES 417 
 
 with sloughing of the skin. When the disease extends into 
 the orbit, it causes orbital celluUtis; thrombosis of the retinal 
 veins, optic neuritis, and atrophy of the optic nerve may fol- 
 low; glaucoma sometimes results, and occasionally inflam- 
 mation of the lacrymal gland and sac. 
 
 Gonorrhoea is responsible for the local infection of the con- 
 junctiva resulting in purulent conjunctivitis in adults and in 
 ophthalmia neonatorum in the new-born. It also gives rise 
 to a form of iritis resembling rheumatic iritis, and much less 
 frquently to a type of conjunctivitis; both of these affections 
 are analogous to gonorrhoeal arthritis, and are due to metas- 
 tasis or the presence of toxins. 
 
 Influenza is almost always accompanied by congestion of the 
 conjunctiva or by acute catarrhal conjunctivitis. There is 
 frequently severe pain in and back of the eyeballs. Many ocu- 
 lar manifestations credited to influenza are probably depend- 
 ent upon the depression which follows the disease; in this 
 category may be placed weakness of accommodation and as- 
 thenopia. Infrequent ocular complications include corneal 
 ulcer, pareses of extrinsic ocular muscles, retrobulbar neuritis, 
 optic neQritis, optic-nerve atrophy, and orbital cellulitis. 
 
 Leprosy attacks the eyelids, frequently producing anaesthetic 
 patches of the skin, loss of lashes and eyebrows, deposit of 
 tubercles, and deformity of the lids. The conjunctiva often 
 presents chronic conjunctivitis, tubercles, and pterygia. The 
 cornea is a common seat of tubercles or leprous keratitis. More 
 rarely the iris and ciliary body present tubercles. 
 
 Malaria infrequently gives rise to the following ocular man- 
 ifestations: keratitis, optic neuritis, retrobulbar neuritis, 
 hemorrhages into the retina and vitreous, amblyopia, and 
 paresis of accommodation. 
 
 Measles is regularly accompanied by a catarrhal conjuncti- 
 vitis with subjective symptoms of greater or lesser severity. 
 In addition, there are very frequently blepharitis, phlydenulce, 
 hordeola, superficial corneal ulceration, and asthenopia. 
 
 Mtimps is complicated by dacryo-adenitis in a small number 
 of instances; this rarely leads to suppuration. CEdema of the 
 lids and chemosis may be present. 
 
418 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 Pneumonia may be complicated by herpes of the cornea 
 sometimes followed by corneal ulceration. 
 
 Relapsing Fever. — In a certain number of cases uveitis and 
 iridocyclitis follow this disease; these generally end in com- 
 plete recovery, but are sometimes succeeded by opacities of 
 the vitreous, atrophy of the globe, and even panophthal- 
 mitis. 
 
 Scarlatina. — Acute catarrhal conjunctivitis is an ocular com- 
 plication of scarlatina, but it is less frequent and milder than 
 in measles; corneal ulcer is sometimes seen; both of these 
 complications are more apt to be found in the convalescent 
 stage than early in the disease. When this disease is com- 
 plicated with nephritis, the characteristic fundus picture of 
 albuminuric retinitis may be seen. 
 
 Septicsemia and Pyaemia give rise to retinal hemorrhages and 
 sometimes to emboli in the choroid and retina; in the latter 
 case, the complication results either in purulent choroiditis, 
 followed by pseudoglioma, or in panophthalmitis. 
 
 Syphilis is frequently responsible for ocular disease. The 
 primary sore may occur on the lids or conjunctiva. Iritis is 
 due to syphilis in at least 25 per cent, of cases; it is an early 
 symptom of the secondary stage, at which time the anterior 
 segment of the eyeball is the vulnerable part; the later stages 
 are more prone to attack the posterior segment, causing cho- 
 roiditis, chorioretinitis, optic neuritis, and diffuse opacity of 
 the vitreous. In the tertiary stage, gummata may be depos- 
 ited in the iris, ciliary body, and the periosteum of the orbital 
 wall, and there may be optic neuritis and optic-nerve atrophy, 
 rarely interstitial keratitis. During this tertiary period paral- 
 ysis and paresis of the ocular muscles, both extra- and intra- 
 ocular, are quite common. Inherited syphilis is responsible 
 for the great majority of instances of interstitial keratitis, and 
 also for some congenital ocular defects. 
 
 Tuberculosis, though rather rarely involving the eye, may 
 affect the iris, choroid, and sclera, presenting characteristic de- 
 posits; still more infrequently the conjunctiva and lids present 
 tuberculous disease. In acute general miliary tuberculosis 
 and in tuberculous meningitis it is not uncommon to find 
 
INFECTIVE DISEASES 419 
 
 small tubercle deposits scattered over the fundus. Inequal- 
 ity of the pupils is seen in pulmonary tuberculosis. 
 
 In the so-called "scrofulous" or "strumous" diathesis, pre- 
 senting a well-known clinical picture but indefinite pathology 
 and association with the tuberculous state, there is a predis- 
 position to many common diseases of the anterior portion of the 
 eye, namely, conjunctivitis, blepharitis, phlyctenular con- 
 junctivitis and keratitis, and occasionally interstitial 
 keratitis. 
 
 Tj^hoid and Typhus Fevers are not particularly prone to 
 ocular manifestations. There may be catarrhal conjunctivi- 
 tis, herpetic ulcers of the cornea, and retinal hemorrhages. 
 During extreme prostration, there is enophthalmos from wast- 
 ing of the orbital tissues, and the cornea may suffer, becoming 
 dry, infiltrated, or ulcerated from imperfect closure of the lids. 
 During convalescence there may be paresis of accommodation 
 and of the extraocular muscles. 
 
 Vaccinia. — There have been examples of accidental inocu- 
 lation of the eyelids and conjunctiva with vaccine virus; in 
 such cases, the pustules excite marked swelling and indura- 
 tion, involvement of the preauricular glands, and tendency to 
 deformity of the lid from subsequent cicatrization. 
 
 Varicella may be complicated by conjunctivitis. The erup- 
 tion may involve the conjunctiva and cornea, resulting in a 
 superficial ulcer of little consequence. 
 
 Variola is responsible for destructive lesions of the lids and 
 eyeball. The lids and conjunctivae are often the site of pus- 
 tules and subsequent cicatrices may cause deformity. Though 
 pustules rarely appear upon the cornea, this part is not infre- 
 quently the seat of keratitis and of ulceration; the latter some- 
 times results in perforation and may present as sequelae, opac- 
 ities, adherent leucoma, or even destruction of the globe. 
 
 Whooping Cough. — Subconjunctival hemorrhage is often 
 seen as a result of the severe paroxysms of coughing; occa- 
 sionally such an extravasation of blood takes place in the lid; 
 rarely it involves the orbit, causing serious damage. 
 
 Yellow Fever, in its early stage, presents congestion of the 
 conjunctiva; this redness is modified by the addition of yel- 
 
420 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 lowish discoloration at a later stage. Subconjunctival and 
 retinal hemorrhages are also found. 
 
 DISEASES OF THE KIDNEYS 
 
 Nephritis presents many ocular manifestations. (Edema is 
 often present in the lids, and may also show itself in the con- 
 junctivae (chemosis). Albuminuric retinitis is common, oc- 
 curring most frequently with the chronic interstitial variety, 
 but liable to complicate any other form, including the ne- 
 phritis of scarlatina and pregnancy. Exophthalmos is often 
 seen. During an attack of urceniia, amblyopia without oph- 
 thalmoscopic changes may be present; the pupils are dilated 
 during this state. 
 
 ailSCEIiLANEOUS DISEASES AITD CONDITIONS 
 
 Consanguinity of Parentage presents examples of ocular 
 abnormalities in the offspring, especially retinitis pigmentosa 
 and congenital ocular malformations. 
 
 Diabetes. — The common ocular complications of diabetes 
 are cataract and hemorrhages in the retina. Less frequently 
 there occur retinitis, optic neuritis, retrobulbar neuritis, iritis, 
 pareses of the external ocular muscles, and paralysis of accom- 
 modation. Diabetics occasionally present sudden and marked 
 changes in the state of refraction of the eye, especially 
 myopia, but also hyperopia, accompanying an increase in the 
 amount of sugar in the urine. 
 
 Gout is sometimes responsible for a form of iritis, for 
 episcleritis and scleritis, and rarely for marginal ulcer of the 
 cornea, glaucoma, and hemorrhagic retinitis. Gouty individ- 
 uals often complain of "dry catarrh," a condition in which the 
 conjunctiva is congested, and the patient experiences a hot 
 feeling in the lids and a sensation as though a foreign body 
 were present; such patients are sometimes subject to attacks 
 of transient periodic episcleritis. 
 
 Headache, when persistent or frequently recurring, should 
 always prompt a careful examination of the eyes. Errors of 
 refraction are conunon causes of headache and neuralgia; not 
 infrequently we find anomalies of the extrinsic ocular muscles; 
 
MISCELLANEOUS DISEASES AND CONDITIONS 421 
 
 less often presbyopia and accommodation weakness. The 
 error of refraction which is most commonly responsible is as- 
 tigmatism; less often hyperopia; the amount of astigmatism 
 may be very moderate, even 0.25 or 0.50 D. The site of the 
 pain varies, but is often supraorbital and frontal. Deprecia- 
 tion of general health is, in many cases, a predisposing factor; 
 thus we often find that the glasses required to cure headaches 
 in individuals who were debilitated are no longer necessary 
 when the system has regained its normal tone after a vacation. 
 
 Migraine. — This affection, thought to depend upon some 
 disturbance in the circulation of the cerebral cortex, is charac- 
 terized by periodic or irregular attacks commencing with 
 blurring of vision with or without scintillating scotoma, often 
 more or less hemianopic in character. After a period varying 
 from several minutes to half an hour, vision again becomes 
 normal; then a very severe headache develops, accompanied 
 often by nausea and vomiting, and followed by marked gen- 
 eral depression. Though dependent, in part at least, upon 
 depreciation in general health and excessive use of the eyes, 
 the attacks are often aggravated by eyestrain; in such cases 
 the seizures are prevented or made less severe by correction 
 of errors of refraction or of heterophoria. 
 
 Rheumatism is responsible for a moderate number of ex- 
 amples of iritis and irido-cyclitis. It is the etiological factor 
 in some cases of gcleritis, episcleritis, tenonitis, and palsies of 
 the extrinsic ocular muscles. 
 
 Rickets. — The subjects of rachitis often present congenital 
 cataract (zonular), interstitial keratitis, and phlyctenular 
 kerato-conj uncti vitis . 
 
 Scurvy is accompanied by hemorrhages beneath the con- 
 junctiva, in the retina, skin of the lids, and occasionally into 
 the orbit. It not infrequently presents a form of night blind- 
 ness which disappears when the affection is recovered from. 
 
 Vertigo, with or without nausea, is often dependent upon 
 the same ocular errors which produce headaches and neu- 
 ralgia. In addition to insufficiencies of the extrinsic ocular 
 muscles, parcses of these muscles may be responsible. 
 
422 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 DISEASES OF THE KIIfD 
 
 Insanity (Functional) presents no ocular symptoms of any 
 importance. Pupillary alterations, including irregularity, are 
 found not infrequently, but are not pathognomonic. 
 
 DISEASES OF THE NERVOUS STSTEDI 
 
 The eye furnishes information of great importance in the 
 diagnosis of diseases of the nervous system, the intimate re- 
 lationship between this part of the human anatomy and the 
 visual organs being evident. Particulars regarding the condi- 
 tion of the optic nerves, the pupils, the eye muscles, the acute- 
 ness of vision, and the fields of vision are of great value. 
 
 Apoplexy gives rise to a nrnnber of ocular manifestations 
 varying according to the part of the brain involved. Retinal 
 hemorrhages may precede the cerebral affection and may serve 
 as a warning of impending danger. 
 
 Friedreich's Disease has no ocular disturbances excepting a 
 peculiar nystagmus consisting of irregular twitchings when the 
 eyes are fixed upon a moving object. Ocular palsies, optic 
 neuritis, and Argyll-Robertson pupils occur rarely. 
 
 Hydrocephalus is often accompanied by optic-nerve atrophy 
 and by strabismus; less frequently optic neuritis is found. 
 
 Meningitis often presents optic neuritis, abnormalities of 
 the pupils, and palsies or spasms of the ocular muscles causing 
 deviations. These ocular manifestations are seen most fre- 
 quently in tuberculous meningitis, in which variety tubercles 
 of the choroid are not infrequently found. 
 
 Myelitis is, in rare instances, accompanied or preceded by 
 optic neuritis, and this is followed by optic-nerve atrophy in 
 some cases. There are disturbances of the pupils, but these 
 are not common nor are they characteristic. If the cervical 
 cord be affected, there may be miosis, narrowing of the palpe- 
 bral aperture, and enophthalmos. 
 
 Paresis (General). — The subjects of this disease often pre- 
 sent inequaUty and irregularity of the pupils, also miosis, and 
 less frequently mydriasis. There is not uncommonly impair- 
 ment or loss of the light reflex {Argyll-Robertson pupil) ; later 
 there is added partial or complete loss of reaction to accommo- 
 
DISEASES OF THE NERVOUS SYSTEM 423 
 
 dation. Sometimes atrophy of the optic nerve with reduction 
 in the acuteness of vision and restriction of the field is noted. 
 Palsies of the third, fourth, and sixth nerves may occur. 
 
 Sclerosis (Disseminated) presents numerous ocular mani- 
 festations; the latter are found in fully one-half of the cases. 
 Nystagmus is a frequent symptom. The fields of vision often 
 exhibit irregular peripheral contraction and central scotoma, 
 either relative or absolute. An incomplete optic-nerve atrophy, 
 generally unilateral, is of common occurrence, resulting from 
 retrobulbar neuritis. There are also partial paralyses of the 
 extraocular muscles, giving rise to diplopia. 
 
 Tabes is accompanied by many ocular signs. The Argyll- 
 Robertson pupil, in which the reaction to light is lost, while 
 that of convergence and accommodation is preserved, is pres- 
 ent in the great majority of cases and usually exists on both 
 sides. A deviation from circular shape, inequality, and 
 marked contraction of the pupil (miosis) are very common; 
 much less frequently mydriasis is present, but it is then very 
 often associated with blindness. Atrophy of the optic nerve 
 occm's often, is an early symptom, is progressive, and gener- 
 ally leads to blindness; with this change in the optic nerve 
 there is reduction in the acuteness of vision and concentric 
 contraction of the field. Ocular palsies are very common ; they 
 often occur early in the disease, involve the third and sixth 
 nerves, rarely the fourth, appear suddenly in many instances, 
 are generally transient, and are accompanied by diplopia — if 
 the third nerve is involved, also by ptosis. Epiphora is some- 
 times observed; also incoordinated movements of the eyeballs. 
 
 Tumor of the Brain (including Abscess) gives rise to choked 
 disc in the majority of cases, generally bilateral, and in most 
 instances more marked on the side of the growth. There may 
 be palsies of the ocular muscles and alterations in the fi^ld of 
 vision. The characteristics of these changes are a great aid 
 in localization. 
 
 FUNCTIONAL NERVOUS DISORDERS 
 
 Chorea. — " True chorea," now generally regarded as an 
 acute infectious disease, is not caused by ocular anomalies. 
 
424 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 Patients with "Habit Chorea" or "Habit Spasm," having 
 choreic movements of the muscles of the lids and secondarily 
 of the face and neck, often suffer from errors of refraction, less 
 frequently from lack of equilibrium of the eye muscles; relief 
 of eyestrain by the wearing of glasses or the correction of the 
 muscular anomaly often effects a cure. 
 
 Coma. — Objective examination of the eyes may give im- 
 portant data in all forms of coma. If dependent upon organic 
 brain disease there may be choked disc, mydriasis, and devia- 
 tion of the eyes. If due to cerebral hemorrhage there may be 
 miosis, inequality of the pupils, and conjugate deviation. 
 With increased intracranial pressure, there may be dilated 
 pupils. If urcemic, albuminuric retinitis may be found. 
 When alcoholic, there may be dilatation of the pupils and 
 pareses of external ocular muscles. If due to poisoning by 
 opium or similar drugs, there will be extreme miosis. 
 
 Epilepsy. — The seizure frequently begins with a visual aura: 
 transient flashes of light, colored sensations, and hemianopic or 
 complete loss of vision. During the attack, there may be nar- 
 rowing of the retinal arteries, the pupils are generally dilated 
 and the light reflex is lost, and there is often spasm of the 
 extrinsic ocular muscles causing conjugate lateral deviation of 
 the eyes. After the seizure, there are distention of the retinal 
 veins, often alterations in size of the pupils, and not infre- 
 quently temporary concentric contraction of the field and re- 
 duction in vision. Not very often, but certainly in some 
 cases, epilepsy is excited by eyestrain, and the number and 
 severity of attacks are reduced by the wearing of glasses. 
 
 Hysteria is sometimes responsible for a great variety of 
 ocular symptoms, the principal ones being diminution in the 
 acuteness of vision (amblyopia and even blindness), concentric 
 contraction of the^eZd of vision for form and colors, becoming 
 more marked with each repeated examination, and reversal in 
 the relative size of the color fields. Other ocular symptoms 
 occurring in hysteria are scotoma, hemianopsia, photophobia, 
 blepharospasm, and monocular diplopia. The pupillary re- 
 flexes and the ophthalmoscopic appearances are normal. The 
 ocular manifestations are almost always referred to one eye. 
 
FUNCTIONAL NERVOUS DISORDERS 425 
 
 Neurasthenia is often accompanied by pain in or around 
 tiie eyes, or headaclie, usually aggravated upon close work, 
 also fatigue and discomfort in reading or near use. In many 
 cases these symptoms depend upon errors of refraction or het- 
 erophoria which in healthy individuals would give rise to no 
 discomfort. These patients often obtain comfort by the wearing 
 o£ correcting lenses or of prisms; but in some cases glasses are 
 ineffective or give only partial relief; then the asthenopia is 
 regarded as " neurasthenic " and is considered a neurosis de- 
 pendent upon a general asthenic condition of the system. 
 
 DISEASES OF THE NOSE, NASO-PHARYNX, AND 
 ACCESS0B7 SINUSES 
 
 The communication between nose and conjunctival sac by 
 means of the lacrymal duct explains the frequent occurrence 
 of ocular symptoms and affections as a result of nasal disease. 
 In coryza there is often conjunctival congestion or acute catar- 
 rhal conjunctivitis with marked lacrymation. In hay fever 
 these conditions are found, and also very annoying itching. In 
 chronic rhinitis, catarrhal or hypertrophic, conjunctivitis, ble- 
 pharitis, and phlyctenular affections are very common; in ad- 
 dition, the nasal swelling may obstruct the Jower end of the 
 lacrymal duct and produce stenosis, dacryocystitis, and lacry- 
 mal abscess. The lacrymal duct may convey infection 
 from the nose to the conjunctival sac and cause corneal 
 ulcer. 
 
 Adenoids not infrequently give rise to catarrhal conjuncti- 
 vitis, follicular conjunctivitis, epiphora, and asthenopia. 
 
 Diseases of the Accessory Sinuses (maxill&ry, ethmoid, sphe- 
 noid, and frontal) are not infrequently responsible for many 
 ocular symptoms and diseases, among which are orbital peri- 
 ostitis and cellulitis, exophthalmos, paresis or paralysis of the 
 ocular muscles (both extrinsic and intrinsic), asthenopia, re- 
 duction in acuteness of vision, changes in the fields of vision 
 including scotomata and increase in size of the blind spot, optic 
 neuritis, neuroretinitis, retrobulbar neuritis, and atrophy of 
 the optic nerve (see p. 83). 
 
426 OCULAR MANIFESTATIONS OF GENERAL DISEASES 
 
 POISONINGS AND INTOXICATIONS 
 
 These conditions are responsible for ocular symptoms and 
 disease, especially retrobulbar neuritis (less frequently optic- 
 nerve atrophy) which results from poisoning by alcohol, to- 
 bacco, wood-alcohol, chloral, iodoform, lead, arsenic (atoxyl), 
 bisulphide of carbon, nitrobenzol, and anilin. 
 
 CONDITIONS OF THE SEXUAL ORGANS AND 
 OBSTETRICAL CONDITIONS 
 
 Excessive sexual intercourse has been held responsible for 
 retinal hemorrhages and for optic-nerve atrophy in men. 
 
 M enstruation. — Ocular diseases often show an exacerbation at 
 the menstrual period, and at this time asthenopic symptoms are 
 often complained of and weakness of accommodation some- 
 times observed. Vicarious menstruation is occasionally rep- 
 resented by subconjunctival, vitreous, or retinal hemorrhage. 
 
 Pregnancy may be complicated by gravidic retinitis so 
 marked as to Justify premature delivery in order to save sight. 
 
 Parturition is accompanied by danger to the eyes of the child : 
 Conjunctival infection may give rise to ophthalmia neonatorum; 
 the use of the forceps during delivery has resulted in bruising 
 of the lids, injury to the cornea, orbital hemorrhage causing 
 exophthalmos, and even rupture of the eyeball. During this 
 period the eyes of the mother may present, on rare occasions, 
 retinal hemorrhages; and if there has been great loss of blood, 
 amblyopia without ophthalmoscopic changes, or reduction of 
 vision with subsequent optic-nerve atrophy may ensue. Pwer- 
 peral infection may result in metastatic choroiditis or in pan- 
 ophthalmitis with loss of the eye. Parturition may also be 
 followed by optic neuritis, atrophy of the optic nerve, retro- 
 bulbar neuritis, retinal hemorrhages, and embolism of the 
 central artery of the retina, though all of these are rare. 
 
 Lactation, if prolonged and causing impairment of the 
 mother's health, may be responsible for paresis of accommo- 
 dation, asthenopic symptoms, and ulcer of the cornea. 
 
INDEX 
 
 Abbreviations, 306 
 Abscess, corneal 141 
 
 lacrymal, 75 
 
 orbital, 79, 81 
 
 retrobulbar, 81 
 
 vitreous, 186, 223 
 Accommodation, 228, 310, 352 
 
 amplitude of, 311 
 
 and convergence, 313 
 
 anomalies of, 352 
 
 Helmholtz theory, 311 ■ 
 
 mechanism of, 310 
 
 paralysis of, 354, 369 
 
 range of, 311 
 
 spasm of, 355 
 
 Tscherning theory, 311 
 Achromatopsia, 281 
 Aooin, 404 
 Adrenalin, 404 
 Advancement of muscles, 377, 382 
 
 limited or partial, 391 
 Alum, 396 
 Alypin, 404 
 Amaurosis, 280 
 Amaurotic cat's eye, 196 
 
 family idiocy, 261 
 Amblyopia, 280 
 
 alcohol, 276 
 
 color, 281 
 
 congenital, 280 
 
 ex anopsia, 280 
 
 from disuse, 280 
 
 hysterical, 284 
 
 malarial, 286 
 
 methyl-alcohol, 286 
 
 quinine, 286 
 
 reflex, 286 
 
 simulated, 284 
 
 tobacco, 276 
 
 toxic, 276 
 
 UTffimic, 258 
 
 wood-alcohol, 286 
 Amblyoscope, 377 
 Ametropia, 309 
 Anaesthetics, local, 403, 410 
 Angle alpha, 309 
 
 gamma, 309 
 
 iris, 198, 206 
 
 meter, 314 
 
 of anterior chamber, 198, 206 
 
 Angle of convergence, 314 
 
 of incidence, 293, 295 
 
 of refraction, 293, 295 
 
 visual, 10 
 Anisometropia, 346 
 Ankyloblepharon, 58 
 Anophthalmos, 86 
 Antiseptic solutions, 393 
 Aphakia, 235 
 Aqueous chamber, 164, 191 
 
 humor, 7, 191 
 Arcus seniUs, 134 
 Argyrol, 400 
 Argyrosis, 397, 400 
 Artificial eyes, 90 
 Asthenopia, 329, 347 
 
 accommodative, 329, 348 
 
 hysterical, 348 
 
 muscular, 348, 385 
 
 nervous, 348 
 
 neurasthenic, 348 
 
 retinal, 348 
 Astigmatic dial, 341 
 Astigmatism, 310, 319, 337 
 
 against the rule, 340 
 
 compound, 339 
 
 corneal, 338 
 
 correction of, 345 
 
 etiology of, 338 
 
 irregular, 337, 347 
 
 lenticular, 338 
 
 mixed, 340 
 
 obhque, 340 
 
 regular, 337 
 
 simple, 339 
 
 symptoms of, 340 
 
 tests for, 341 
 
 treatment of, 345 
 
 varieties of, 339 
 . with the rule, 340 
 Astigmia, 337 
 Astringent remedies, 395 
 Atropine, 170, 401 
 
 Kritatidn, 401 
 
 poisoning, 170, 401 
 
 Background. 25, 33 
 Bandages, eye, 4i2 
 Beer's knife, 45 
 Bifocal lenses, 350 
 
 427 
 
428 
 
 INDEX 
 
 Black eye, 65 
 
 Blennorrhoea, conjunctival, 103 
 
 of the lacrymal sac, 69 
 Blepharitis, 39 
 Blepharophimosis, 58 
 Blepharoplasty, 56 
 Blepharospasm, 5, 62 
 Blind spot, 17 
 
 enlargement of, 84 
 Bloodletting, 405 
 Bluestone, 118, 397 
 Boracic (boric) acid, 394 
 Borax, 396 
 
 Bowman's membrane, 133 
 BuUer's shield, 105 
 Buphthalmos, 86, 218 
 
 Calomel, 397 
 Camphor, 397 
 Canal of Petit, 227 
 
 Schlemm's, 177, 199 
 Canalicuh, lacrjTnal, 66, 68, 69 
 Canaliculus dilator, 68, 71 
 
 knife, 68 
 
 slitting of, 72 
 Canthoplasty, 52 
 
 temporary, 53, 107 
 Canthotomy, 53, 107 
 Canthus, external, 38 
 
 internal, 38 
 Capsule of Tenon, 78, 158, 357 
 Capsulotomy, 238 
 
 preliminary, 234 
 Carbolic acid, 399 
 Carbon-dioxide snow, 407 
 Cardinal points of the eye, 308 
 Caruncle, 38 
 
 sinkmg of, 382 
 Cataract, 228 
 
 after-, 245 
 
 anterior capsular, 242 
 
 anterior polar, 138, 228, 242 
 
 artificial ripening of, 233 
 
 black, 232 
 
 capsular, 228 
 
 capsulo-lenticular, 228, 232 
 
 central, 244 
 
 chalky, 232 
 
 complete, 228 
 
 complicated, 244 
 
 concussion, 244 
 
 congenital, 241 
 
 cortical, 230 
 
 etiology of, 229 
 
 fluid, 228 
 
 fusiform, 244 
 
 hard, 228, 229 
 
 Cataract, hypermature, 232 
 
 immature, 231 
 
 incipient, 231 
 
 juvenile, 241 
 
 lamellar, 228, 243 
 
 lenticular, 228 
 
 mature, 231, 233 
 
 monocular, 235 
 
 Morgagnian, 232 
 
 nuclear, 230 
 
 partial, 228, 242 
 
 pathology of, 232 
 
 posterior polar, 228, .242 
 
 primary, 228 
 
 progressive, 228 
 
 punctate, 244 
 
 pyramidal, 242 
 
 ripe, 232 
 
 secondary, 228, 242, 244 
 
 senile, 229, 230 
 
 shrunken, 232 
 
 simple, 230 
 
 soft, 228, 229, 241 
 
 stages of, 231 
 
 stationary, 228, 242 
 
 swelling of, 231 
 
 symptoms of, 230 
 
 traumatic, 244 
 
 treatment of, 232 
 
 uncommon forms of, 228, 244 
 
 varieties of, 219 
 
 zonular, 243 
 Cataract extraction, 234, 236 
 
 combined, 234 
 
 complications of, 241 
 
 favorable time for, 233 
 
 indications, 236 
 
 in myopia, 247 
 
 linear, 240 
 
 of lens in capsule, 241 
 
 prognosis, 235 
 
 eimi)le, 234 
 
 suction method, 247 
 
 with iridectomy, 234 
 
 without iridectomy, 234 
 Catarrh, angular, 101 
 
 dry, 94 
 
 follicular, 99, 101 
 
 spring, 127 
 
 vernal, 128 
 Cauterants, 398 
 Cautery, 64, 127, 143, 400 
 Cavernous sinus, thrombosis of, 82 
 Cerebral decompression, 275 
 Chalazion, 43, 44 
 Chamber, anterior, 164, 198 
 angle of, 198 
 
INDEX 
 
 429 
 
 Chamber, anterior, sinus of, 198 
 aqueous, 164, 198 
 posterior, 164, 198 
 Chemosis, 4, 81, 103 
 Chiasm, 288 
 Chlorine water, 399 
 Choked disc, 271, 272 
 Chorio-capillaris, 182 
 Choroid, anatomy of, 182 
 coloboma of, 187 ■ 
 diseases of, 182 
 inflammations of, eee Cho- 
 
 roidUis 
 physiology of, 182 
 rupture of, 187 
 sarcoma of, 194 
 tubercle of, 187 
 vessels of, 35, 182 
 Choroidal atrophy, 183, 185 
 
 ring, 33 
 Choroiditis, 182 
 anterior, 185 
 central, 185 
 circumscribed, 184 
 diffuse, 184 
 disseminated, 184 
 exudative, 182 
 myopic, 185 
 non-suppurative, 182 
 senile, 185 
 suppurative, 186 
 sjTJhilitic, 185 
 Choroidoretinitis, 182, 259 
 Cilia, 2, 38, 46 
 CiUary body, 177 
 
 anatomy of, 177 
 diseases of, 177 
 inflammations of. see Cy- 
 
 cliiis 
 injuries of, 181 
 vessels of, 177 
 ganglion, 78 
 injection, 93, 135, 166 
 muscle, 177 
 nerves, 177 
 processes, 177 
 tenderness, 8 
 Circumcorneal injection, 93, 135 
 Cleansing solutions, 393, 411 
 Cocaine, 25, 402, 403 
 Cold compresses, 407 
 Color blindness, 281, 283 
 central perception of, 18 
 perception theories, 281 
 peripheral perception of, 18 
 scotoma, 18 
 sense, 10, 18, 281 
 
 Color vision tests, 282 
 Colored vision, 283 
 Colors, field for, 18 
 Conjunctiva, 2, 92 
 
 acute blennorrhoea of, 103 
 
 anatomy of, 92 
 
 bulbar, 92 
 
 burns of, 131 
 
 diseases of, 94 
 
 ecchymosis of, 94 
 
 foreign bodies in, 131 
 
 fornix, 92 
 
 hypersemia of, 94 
 
 inflammations of, see Conjunc- 
 tivitis 
 
 injuries of, 131 
 
 nerves of, 93 
 
 ocular, 92 
 
 palpebral, 39, 92 
 
 retrotarsal, 4, 92 
 
 vascular supply of, 92 
 Conjunctival folUcles, 92 101 
 
 injection, 93 
 
 papillae, 92 
 
 sac, 92, 199 
 Conjunctivitis, acute catarrhal, 96 
 
 acute simple, 96 
 epidemic, 98 
 
 angular, 101 
 
 catarrhal, in new-bom, 110 
 
 chronic catarrhal, 100 
 
 chronic simple, 100 
 
 croupous, 112 
 
 diphtheritic, 110 
 
 diplobacillus, 101 
 
 eczematous, 123 
 
 electric, 97 
 
 exanthematous, 98 
 
 foUicular, 99, 101 
 
 gonorrhoea], 103 
 
 granular, 113 
 
 infantile purulent, 107 
 
 lacrymal, 69, 98 
 
 membranous, 110 
 
 metastatic gonorrhoeal, 107 
 
 Morax-Axenfeld, 101 
 
 Parinaud's, 123 
 
 phlyctenular, 123 
 
 purulent, 103 
 
 of young girls, 110 
 
 pustular, 124 
 
 snow, 97 
 
 traumatic, 97 
 Conus, 185 
 Convergence, 313 
 
 amplitude of, 314 
 
 and accommodation, 314 
 
430 
 
 INDEX 
 
 Convergence, angle of, 314 
 far point of, 314 
 near point- of, 314 
 negative, 314 
 positive, 315 
 range of, 314 
 Copper sulphate, 118, 397 
 Coquilles, 408 
 Cornea, abscess of, 141 
 anatomy of, 133 
 bums of, 156 
 conical, 152 
 diseases of, 135 
 foreign bodies in, 154 
 infiltration of, 105, 134, 146 
 inflanunatiDns of, see Keratitis 
 injuries of, 154 
 opacities of, 5, 21, 117, 153 
 paracentesis of, 143 
 perforation of, 137, 144 
 protrusions of, 150 
 ring abscess of, 141 
 sensitiveness of, 5 
 staphyloma of, 117, 138, 150 
 tattooing of, 154 
 transverse calcar. film of, 149 
 ulcer of, 117, 135 
 wounds of, 156 
 Corneal corpuscles, 134 
 epithelium, 133 
 facet, 136, 140 
 fistula, 138 
 lacunae, 134 
 lamelte, 133 
 leucoma, 153 
 macula, 153 
 nebula, 153 
 reflex, 5 
 ulcer, 117 
 
 annular, 140 
 
 atheromatous, 141 
 
 catarrhal, 141 
 
 central, 139 
 
 deep, 139 
 
 dendriform, 141 
 
 herpetic, 140 
 
 indolent, 140 
 
 infected, 139 
 
 marginal ring, 140 
 
 Mooren's, 140 
 
 phytenular, 123 
 
 pneumococcus, 139 
 
 rodent, 140 
 
 serpent, 139 
 
 serpiginous, 139 
 
 simplej 139 
 
 sloughing, 139 
 
 Corneal ulcer, transparent, 140 
 Corrosive sublimate, 394, 398 
 Credo's method of prophylaxis, 109 
 Cyclitis, 168, 178 
 
 plastic, 179 
 
 purulent, 180 
 
 serous, 178 
 
 simple, 178 
 Cyclodialysis, 217 
 Cyclophoria, 384 
 Cycloplegia, 354 
 Cycloplegics, 349, 400 
 Cylinder, see Lenses, cylindrical 
 Cyst, Meibomian, 44 
 
 tarsal, 44 
 Cystoid cicatrix, 208 
 
 Dacbtoadenitis, 69 
 Dacryocystitis, 69, 75 
 Day blindness, 288 
 Decompression, cerebral, 275 
 Descemet'a membrane, 134 
 Descemetitis, 150, 178 
 Deviation, latent, 361, 384 
 
 manifest, 361 
 
 primary, 362 
 
 secondary, 362 
 Deviations, varieties of, 360 
 Diaphanosoopy, 36 
 Dilator pupillse, 164 
 Dionin, 404 
 Diopter, 303 
 Dioptric apparatus, 308 
 
 medium, 295 
 
 system, 303 
 Diplopia, 359, 363 
 
 crossed, 360 
 
 homonymous, 359 
 
 horizontal, 360 
 
 monocular, 248, 284 
 
 vertical, 360 
 Disc, see O'ptic disc 
 
 choked, 271, 272 
 
 diameter, 29 
 
 Placido's, 4, 344 
 Discission for after-cataract, 247 
 
 of the lens, 241, 246 
 Disinfectants, 398 
 Distichiasis, 46 
 Dressings, 412 
 Duboisine, 402 
 
 Ectropion, 46, 53, 117 
 cicatricial, 53 
 mechanical, 53 
 operations for, 54 
 paralytic, 53 
 
INDEX 
 
 431 
 
 Ectropion, senile, 53 
 
 spasmodic, 54 
 Electricity, 407 
 Electrodes, eye, 143 
 Emmetropia, 309, 319 
 Emphysema, 65 
 Enophthalmos, 4, 79 
 Entropion, 46, 47, 117 
 
 cicatricial, 47 
 
 operations for, 48 
 
 senile, 47 
 
 spasmodic, 47 
 Enucleation of eyeball, 86 
 
 indications for, 88, 190 
 
 with artificial globe, 89 
 Epicanthus, 63 
 Epilation, 46 
 Epiphora, 53 
 Episcleral tissue, 92, 94 
 
 injection, 94 
 Episcleritis, 159 
 
 transient periodic, 160 
 Erythropsia, 283 
 Eserine, 209, 403 
 Esophoria, 384 
 Esotropia, 372, 374 
 Ethyl hydrocuprein, 400 
 Eucain B, 404 
 Euphthahnin, 25, 402 
 Examination, dark-room, 21 
 
 external, 7 
 
 functional, 10 
 
 objective, 21 
 
 of media, 23 
 
 ophthalmoscopic, distant, 23 
 direct, 28, 318 1 
 indirect, 26, 318 
 for refraction, 24, 30, 317 
 
 subjective, 10 
 Exophoria, 384 
 Exophthalmos, 4, 79, 83 
 
 intermittent, 83 
 
 pulsating, 83 
 Exotropia, 372, 378 
 Eyeball, 77 
 
 associated movements of, 358 
 
 atrophy of, 186, 190, 203 
 
 congemtal anomalies of, 86 
 
 enucleation of, 86 
 
 evisceration of, 89 
 
 with artificial vitreous, 90 
 
 inspection of, 4 
 
 method of exposing, 7 
 
 movements of, 358 
 
 operations upon, 86 
 
 palpation of, 8 
 
 tension, 8 
 
 Eyecup, 394 
 Eyeglasses, 349 
 Eyestrain, 347 
 Eyes, artificial, 90 
 
 Far point, 311 
 Farsightedness, 326 
 Fibres of Gratiolet, 288 
 
 Mueller's, 251 
 Filtering cicatrix, 208 
 Fixation, field of, 358 
 
 line of, 309 
 Fluorescein, 6, 136, 405 
 Focus, conjugate, 294, 299 
 
 negative, 300 
 
 principal, 294, 299, 309 
 
 real, 300 
 
 virtual, 294 
 Polliculosis, 102 
 Fontana, spaces of, 199 
 Forceps, advancement, 380 
 
 chalazion, 45 
 
 cilia, 46 
 
 entropion, 48 
 
 fixation, 237 
 
 trachoma, 120 
 Form sense, 10 
 Formalin, 399 
 Fornix, 4, 92 
 
 Fovea centralis, 36, 250, 251 
 Fundus, 25, 33 
 
 physiological variations, 36 
 
 reflex, 24 
 Fusion, sense of, 374, 377 
 
 Ganglion, Ciliary, 78 
 
 Gasserian, 145 
 Gerontoxon, 134 
 Gland, lacrimal, 67 
 Glands, Meibomian, 38, 39, 44 
 
 of Moll, 38 
 
 Zeiss', 38, 43 
 Glaucoma, 198 
 
 absolute, 203 
 
 active stage of, 201 
 
 acute inflammatory, 200 
 
 chronic inflammatory, 203 
 
 congenital, 86, 218 
 
 congestive, 199 
 
 degeneration stage of, 203 
 
 differential diagnosis, 167, 207 
 
 etiology of, 205 
 
 fulminans, 203 
 
 hemorrhagic, 216, 218 
 
 malignant, 214 
 
 non-congestive, 199, 204 
 
 non-inflammatory, 199, 204 
 
432 
 
 INDEX 
 
 Glaucoma, occiirrence of, 205 
 
 pathology of, 206 
 
 primary, 198 
 
 prodromal stage of, 200 
 
 prognosis of, 208 
 
 secondary, 198, 218 
 
 simple, 199, 204 
 
 subacute, 199 
 
 symptoms of, 200, 204 
 
 treatment of, 208 
 
 varieties of, 199 
 Glaucomatous cup, 202 
 
 excavation, 202 
 
 halo, 203 
 
 ring, 203 
 
 state, 201 
 Glioma of the retina, 194 
 
 pseudo-, 186, 196 
 Gonococci, 103, 108 
 Gonorrhceal conjunctivitis, 103 
 metastatic, 107 
 
 iritis, 172 
 
 ophthalmia, 103 
 Graefe knife, 237 
 Grafts, Thiersch, 57, 130 
 
 Wolfe, 57 
 Granular lids, 113 
 Grattage, 121 
 
 Hand movements, 13 
 Hemeralopia, 288 
 Hemiachromatopsia, 291 
 Hemianopia, 290 
 Hemianopsia, 289, 290 
 
 absolute, 291 
 
 altitudinal, 291 
 
 binasal, 290 
 
 bitemporal, 290 
 
 complete, 291 
 
 crossed, 290 
 
 homonymous, 290 
 
 incomplete, 291 
 
 lateral, 290 
 
 relative, 291 
 
 transient, 292 
 Hemiopia, 290 
 
 Hemiopic pupillary reaction, 291 
 Hemorrhage, preretinal, 263 
 
 subconjunctival, 94 
 
 subhyaloid, 263 
 Herpes comese, 149 
 
 zoster ophthalmicus, 42, 149 
 Heterophoria, 361, 384 
 
 etiology of, 384 
 
 operations for, 391 
 
 symptoms of, 384 
 
 tests for, 385 
 
 Heterophoria, treatment of, 
 389 
 varieties of, 384 
 Heterotropia, 361, 371 
 Hetol, 405 
 
 Hole in the macula, 261 
 Holocain, 404 
 Homatropine, 26, 349, 402 
 Hordeolum, 43 
 Hot compresses, 407 
 Hyalitis, 220 
 Hyaloid artery, 220 
 
 J>ersistent, 220, 242 
 , 220 
 
 membrane, 220 
 Hydrophthalmos, 218 
 Hyoscyamine, 402 
 Hyperesophoria, 384 
 Hyperexophoria, 384 
 Hypermetropia, see Hyperopia 
 Hyperopia, 310, 319, 326 
 
 absolute, 328 
 
 axial, 326 
 
 etiology of, 326 
 
 facultative, 328 
 
 latent, 328 
 
 manifest, 328 
 
 ocular changes in, 327 
 
 of curvature, 326 
 
 symptoms of, 329 
 
 tests for, 329 
 
 total, 328 
 
 treatment of, 330 
 
 varieties of, 328 
 Hypertropia, 372 
 Hyphsema, 7, 173 
 Hjrperphoria, 384 
 Hypopyon, 7, 137 
 
 keratitis, 139 
 
 ICHTHYOIi, 398 
 
 Illumination, oblique, 20 
 Image, false, 359 
 
 true 359 
 Images, double, 359, 363 
 
 formation of, 300 
 
 negative, 294, 300 
 
 real, 294, 300 
 
 virtual, 293, 300 
 Imbalance, muscular, 361 
 Incidence, angle of, 293, 295 
 Inspection of the eye, 1, 5 
 Insufficiency, see Heterophoria 
 Intermarginal space, 38 
 Interpupillary distance, 349 
 Iodine, tincture of, 143, 399 
 Iodoform, 142, 400 
 
INDEX 
 
 433 
 
 Iridectomy, 209 
 
 indications for, 214 
 
 for artificial pupil, 215 
 
 for glaucoma, 211 
 results of, 213 
 
 optical, 215, 243 
 
 preliminary to cataract ex- 
 traction, 235 
 Iridocyclitis, 165, 168, 178 
 Iridodialysis, 173 
 Iridodonesis, 248 
 Iridoplegia, 173 
 
 reflex, 176 
 Iridosclerectomy, 217 
 Iridotomy, 174 
 Iris, anatomy of, 164 
 
 angle, 198, 206 
 
 bomb6, 169 
 
 coloboma of, 213 
 
 diseases of, 164 
 
 inflammation of, see Iritis 
 
 injuries of, 173 
 
 muscles of, 164 
 
 nerves of, 165 
 
 operations upon, 174, 209 
 
 prolapse of, 173, 240 
 
 tremulous, 248, 232, 235 
 
 tumors of, 173 
 
 vessels of, 165 
 Iritis, 165 
 
 acute, 165 
 
 chronic, 165 
 
 diabetic, 172 
 
 gonorrhoeal, 172 
 
 gouty, 172 
 
 idiopathic, 169 
 
 nodular, 165 
 
 papulosa, 171 
 
 plastic, 165 
 
 primary, 165 
 
 purulent, 165 
 
 rheumatic, 171 
 
 scrofulous, 172 
 
 secondary, 165 
 
 septic, 172 
 
 serous, 165, 178 
 
 spongy, 166 
 
 symjjathetic, 172 
 
 syphilitic, 171 
 
 traumatic, 172 
 
 tuberculous, 172 
 Irrigation of anterior chamber in 
 cataract extraction, 239 
 
 Jaeger's test types, 14 
 Jequiritol, 122 
 Jequirity, 122 
 
 Keratbctasia, 152 
 Keratitis, 134 
 
 accompanying herpes zoster, 
 42 
 
 band-shaped, 149 
 
 bullous, 149 
 
 dendritic, 141 
 
 desiccation, 145 
 
 e lagophthalmo, 145 
 
 fascicular, 124 
 
 from defective closure of lids, 
 145 
 
 herpetic, 140 
 
 hypopyon, 139 
 
 interstitial, 146 
 
 marginal, 123 
 
 neuroparalytic, 145 
 
 non-suppurative, 135, 149 
 
 parenchymatous, 146 
 
 phlyctenular, 123, 135 
 
 profunda, 149 
 
 punctate, 150, 166, 178 
 
 sclerosing, 149 
 
 superficial punctate, 149 
 
 suppurative, 135 
 
 vascular, 116 
 
 vasculo-nebulous, 116 
 
 vesicular, 149 
 
 xerotic, 145 
 Keratocele, 137 
 
 Keratoconjunctivitis, phlyctenu- 
 lar, 123 
 Keratoconus 152 
 Keratoglobus, 153, 218 
 Keratomalacia, 145 
 Keratoscope, 5, 344 
 
 Lacrtmal abscess, 75 
 
 apparatus, anatomy of, 67 
 
 diseases of, 69 
 canalicuU, 67, 68, 69 
 conjunctivitis, 69, 98 
 ducts, 67 
 fistula, 76 
 gland, 67 
 probes, 71 
 puncta, 67, 68, 69 
 sac, 2, 67 
 
 blennorrhcea of, 69 
 
 catarrh of, 69 
 
 chronic inflammation of, 
 69 
 
 destruction of, 75 
 
 extirpation of, 74 
 
 incision into, 75 
 secretion, 68 
 sound, 71 
 
434 
 
 INDEX 
 
 Lacrymal styles, 73 
 
 syringe, 71 
 Lagophthaknos, 62, 145 
 Lamina cribrosa, 270 
 
 vitrea, 182 
 Lashes, 2, 38 
 Lead acetate, 397 
 LelDer's disease, 279 
 Leech, artificial, 170, 405 
 Leeches, 107, 170, 209, 405 
 Lens, anatomy of, 227 
 
 anterior capsule of, 227 
 
 at different periods of life, 228 
 
 capsule of, 227 
 
 cortex, 227 
 
 crystalline, 227 
 
 diseases of, 227 
 
 dislocation of, 247 
 
 function of, 228 
 
 laminae of, 227 
 
 luxation of, 248 
 
 measure, 306 
 
 nucleus of, 227 
 
 objective, 26 
 
 opacities of, 21, 228 
 
 physiology of, 228 
 
 posterior capsule of, 227 
 
 reflex of, 228 
 
 sclerosis of, 228 
 
 sectors of, 227 
 
 stellate figure of, 227 
 
 subluxation of, 247 
 
 suspensory ligament of, 227 
 Lenses, oifocal, 350 
 
 converging, 297 
 
 cylindrical, 301 
 
 axis of, 302, 345 
 
 decentering of, 390 
 
 diverging, 298 
 
 estimation of strength of, 305 
 
 finding of centre of, 306 
 
 magnifying, 297 
 
 meniscus,. 297, 298 
 
 minus, 298 
 
 negative, 298 
 
 numeration of, 302 
 
 of ophthalmoscope, 23 
 
 pebble, 350 
 
 periscopio, 298, 350 
 
 plus, 297 
 
 positive, 297 
 
 recognition of kind, 305 
 
 reducing, 298 
 
 spherical, 297 
 action of, 298 
 concave, 298 
 convex, 297 
 
 Lenses, spherical, conjugate foci 
 of, 299 
 focal distance of, 299 
 foci of, 299 
 
 formation of images, 300 
 negative focus of, 300 
 positive focus of, 300 
 principal axis of, 298 
 real focus of, 300 
 secondary axes of, 299 
 virtual focus of, 300 
 toric, 350 
 
 varieties of, 297, 306 
 Leucoma, adherent, 137, 153 
 
 corneal, 5, 153 
 Levator palpebrse superioris, 38 
 
 advancement of, 62 
 Lid clamp, 45, 48 
 retractors, 7 
 Lids, anatomy of, 38 
 burns of, 65 
 diseases of, 39 
 ecchymosis of, 65 
 emphysema of, 65 
 epithelioma of, 64 
 eversion of, 2 
 examination of, 2 
 granular, 113 
 injviries of, 64 
 muscles of, 38 
 nerve supply of, 39 
 oedema of, 41 
 physiology of, 38, 39 
 syphilis of, 41 
 tumors of, 63 
 vaccinia of, 41 
 vascular supply of, 39 
 wounds of, 65 
 Ligaments, check, 357 
 
 tarsal, 39 
 Ligamentum pectinatum, 134, 198 
 Light difference, 19 
 minimum, 19 
 perception, 13, 19, 236 
 projection, 236 
 rays of, 252 
 sense, 10, 19 
 Limbus, 92, 133 
 Line of fixation, 309 
 
 visual, 309 
 LjTnph spaces, anterior, 199 
 posterior, 199 
 
 Macropsia, 183, 253 
 Macula, corneal, 5, 153 
 
 lutea, 29, 36, 250 
 Macular fibres, 275, 288, 291 
 
INDEX 
 
 435 
 
 Maddox rod, 386 
 
 Magnet extraction, 225 
 
 Magnets, eye, 225 
 
 Mariotte's blind spot, 17 
 
 Mask, ocular, 240 
 
 Massage, 407 
 
 Media, examination of, 20, 24 
 
 opacities of, 21, 24, 221 
 Mercuric chloride^ 394, 398 
 Mercury, ammomated, 397 
 
 yellow oxide of, 397 
 Metamorphopsia, 183, 253 
 Meter angle, 314 
 Methyl alcohol amblyopia, 286 
 Mica glasses, 408 
 Microphthalmos, 86 
 Micropsia, 183, 253 
 Milium, 64 
 Mind-blindness, 248 
 Miotics, 209, 403 
 Mirrors, 293 
 
 concave, 293 
 
 convex, 294 
 
 focal length of, 294 
 
 formation of images by, 294 
 
 plane, 293 
 MoUuscum, 63 
 
 Motility, disturbances of, 357 
 Mucocele, 69, 83 
 Muscse volitantes, 222 
 Muscle, Mueller's, 39 
 Muscle-stretching, 371 
 Muscles, eye, 357 
 
 action of, 357 
 advancement of, 382 
 anatomy of, 357 
 nerve supply of, 357 
 physiology of, 357 
 tenotomy of, 377, 381 
 Mydriasis, 173, 349 
 Mydriatics, 25, 349, 400 
 Myopia, 310, 319, 331 
 
 axial, 332 
 
 choroiditis of, 185 
 
 etiology of, 332 
 
 high, 333, 334 
 
 malignant, 333 
 
 operative treatment of, 337 
 
 ophthalmoscopic signs, 334 
 
 prognosis of, 335 
 
 progressive, 333 
 
 simple, 333 
 
 stationary, 333 
 
 symptoms of, 333 
 
 tests for, 334 
 
 treatment of, 335 
 Myopic crescent, 185, 334 
 
 Nasal accessory sinuses, disease 
 of, 83 
 
 duct, 67 
 
 probing the, 72 
 stricture of, 70 
 Near point, 311 
 Nearsightedness, 331 
 Nebula, corneal, 5, 153 
 NeedUng of the lens, 241, 247 
 
 for after-cataract, 246 
 Neosalvarsan, 405 
 Neuritis, descending, 271, 272 
 
 optic, intraocular, 271 
 
 retrobulbar, acute, 275 
 chronic, 276 
 Neuroretinitis, 253, 273 
 New-bom, catarrhal conjunctivi- 
 tis of, 110 
 
 purulent conjunctivitis of, 107 
 Night bhndness, 266, 287 
 Nodal points, 308 
 Novocain, 401 
 Nyctalopia, 268, 287 
 Nystagmus, 391 
 
 labyrinthine, 391 
 
 lateral, 391 
 
 miner's, 391 
 
 mixed, 391 
 
 rotatory, 391 
 
 vertical, 391 
 
 Old sight, 313, 353 
 Opaque nerve fibres, 36 
 Operation, Adam's, 54 
 
 De Grandmont's, 60 
 
 Elliot's, 216 
 
 Gaillard-Arlt,.52_ 
 
 Graefe's, for ptosis, 60 
 
 Heine's, 217 
 
 Herbert's, 208 
 
 Hess', 61 
 
 Hotz's, 50 
 
 Jaesche-Arlt, 49 
 
 Kronlein's, 91 
 
 Lagrange's, 217 
 
 Motais', 62 
 
 Mules', 90 
 
 Pagenstecher's, 60 
 
 Panas', 61 
 
 Saemisch's, 144 
 
 Snellen's, 54 
 
 Streatfeild-Snellen, 51 
 
 VY, 64 
 
 Wharton Jones', 54 
 Operations, gen. rules for, 408 
 Ophthalmia, 95 
 
 electric, 97 
 
436 
 
 INDEX 
 
 Ophthalmia, Egyptian, 118 
 gonorrhoea!!^^ 103 
 neonatorum, 107 
 phlyctenular, 123 
 pustular, 124 
 scrofulous, 123 
 sympathetic, 188 
 Ophthalmitis, sympathetic, 188 
 Ophthalmometer, 343 
 Ophthalmoplegia, external, 369 
 internal, 355, 369 
 total, 369 
 Ophthalmoscope, 22 
 electric, 23 
 theory of, 31 
 Ophthalmoscopic examination, see 
 
 Examination 
 Optic disc, 27, 33 
 
 congestion of, 271 
 cupping of, 34, 202, 250 
 excavation of, 34, 202 
 hyperaemia of, 271 
 physiological depression 
 
 of, 34, 202 250 
 temporal pallor of, 276 
 gangUa, primary, 288 
 nerve, 27, 33, 270 
 anatomy of, 270 
 lymph spaces of, 270 
 Optic-nerve atrophy, 277 
 
 choroiditic, 183, 278 
 gray, 277 
 inflammatory, 277 
 neuritic, 277 
 non-inflammatory, 277 
 postneuritic, 273 
 postpapillitic, 277, 278 
 primary, 277, 278 
 progressive, 277 
 retinitic, 254, 278 
 secondary, 277 
 simple, 277 
 central artery and vein of, 
 
 34, 250 
 diseases of, 270 
 head of, 33, 250 
 inflammation of, 271 
 tumors of, 270 
 Optic neuritis, 271 
 
 intraocular, 271 
 orbital, 275 
 
 retrobulbar, 271, 275, 
 276 
 radiations, 288 
 tracts, 288, 289 
 Optical axis, 309 
 Ora serrata, 250 
 
 Orbicularis muscle, 38 
 Orbit, abscess of, 79 
 
 anatomy of, 77 
 
 caries of, 80 
 
 cavities surrounding the, 77 
 
 contents of, 77 
 
 diseases of, 78 
 
 exenteration of, 91 
 
 fistula of, 80 
 
 injuries of, 85 
 
 necrosis of, 80 
 
 nerves of, 78 
 
 tumors of, 85 
 
 vessels of, 78 
 Orbital celluhtis, 81 
 
 fascia, 77 
 
 periostitis, 79 
 
 phlegmon, 81 
 Orthophoria, 361, 384 
 Orthoptic training, 376 
 
 Palpation op the eyeball, 8 
 Palpebral conjunctiva, 39 
 
 fascia, 39 
 Pannus, 116, 125 
 Panophthalmitis, 192 
 Papilla, 27, 33, 250 
 Papillitis, 271, 273 
 Papillcfidema, 271, 272 
 Paracentesis needle, 144 
 Paralysis, associatea, 369 
 basilar, 369 
 central, 369 
 conjugate, 369 
 cortical, 369 
 nuclear, 369 
 
 of association centres, 369 
 of external rectus, 364 
 of inferior obUque, 366 
 
 rectus, 365 
 of internal rectus, 364 
 of ocular muscles, 361 
 
 muscles, diagnosis of, 367 
 muscles, etiology of, 369 
 muscles, pathology of, 370 
 muscles, prognosis of, 370 
 muscles, symptomsof , 361 
 muscles, varieties of, 364 
 muscles, treatment of ,370 
 of superior oblique. 366 
 
 rectus, 365 
 orbital, 369 
 peripheral, 369 
 third nerve, 59, 368 
 treatment of, 370 
 Pebbles, 350 
 Perimeter, 16, 373 
 
INDEX 
 
 437 
 
 Periorbita, 77 
 Peritomy, 122 
 Phlyctenule, 123 
 Phlyctenular conjunctivitis, 123 
 
 keratitis, 123, 135 
 
 ophthalmia, 123 
 
 pannus, 125 
 Phorometer, 388 
 Photometer, 19 
 Photophobia, 125 
 Photophthalmia, 97 
 Photopsia, 267 
 Phthiriasis palpebrarum, 41 
 Phthisis bulbi, 192 
 Pilocarpine, 209, 403 
 Pinguecula, 93 
 Pink eye, 98 
 Placido's disc, 5, 344 
 Plate, horn or metal, 48 
 Plica semilunaris, 92 
 Potassium permanganate, 399 
 Presbyopia, 313, 353 
 Principal points, 308 
 Prism, 295 
 
 apex of, 295 
 
 base of, 295 
 
 centrads, 296 
 
 degrees, 296 
 
 diopters, 296 
 
 exercises, 371, 389 
 
 geometrical angle of, 296 
 
 rotary, 388 
 Prisms, numbering of, 296 
 
 position of, 296 
 
 refracting angle of, 295, 296 
 
 refraction by, 296 
 
 strength of, 296 
 
 uses of, 296, 371, 389, 390 
 Projection, 359 
 
 false, 362 
 
 light, 236 
 Proptosis, 4, 79, 83 
 Protargol, 400 
 Pseudo-gUoma, 186, 196 
 Pseudo-neuritis, 271 
 Pseudo-pterygium, 131 
 Pterygium, 130 
 Ptosis, 58, 63 
 
 mechanical, 59 
 
 operations for, 59 
 Pulsation of disc vessels, 35, 
 
 202 
 Puncta, lacrymal, 66, 67, 68 
 Punctum, eversion of, 68 
 
 proximum, 311 
 
 remotum, 311 
 Pupil, 174 
 
 Pupil, accommodation and conver- 
 gence reflex of, 175 
 
 Argyll-Robertson, 176 
 
 artificial, 174, 215 
 
 consensual contraction of, 175 
 
 contraction of, 174 
 
 dilatation of, 25, 175 
 
 dilator of, 164 
 
 direct reflex of, 175 
 
 exclusion of, 169 
 
 hemiopic, 291 
 
 indirect reflex of, 175 
 
 irregular, 166 
 
 occlusion of, 169 
 
 reflexes of, 175 
 
 seclusion of, 169 
 
 sphincter of, 164 
 Pupillary membrane, 165 
 persistent, 165 
 
 reflex paths, l76 
 
 Quinine amblyopia, 286 
 
 Radium, 407 
 Ray, axial, 298 
 
 incident, 293 
 
 reflected, 293 
 
 secondary, 299 
 Rays, absorption of, 293 
 
 convergent, 297 
 
 divergent, 293, 298 
 
 of hght, 293 
 
 parallel, 293 
 
 reflection of, 293 
 
 refraction of, 295 
 Reading-glasses, 353 
 Reflection, 293 
 
 by a concave mirror, 293 
 convex mirror, 294 
 plane mirror, 293 
 
 laws of, 293 
 Reflex, corneal, 4 
 
 fundus, 24 
 
 senile lens, 228 
 Refracting media of the eye, 308 
 
 surfaces of the eye, 308 
 Refraction, 295 
 
 angle of, 295 
 
 by prisms, 296 
 
 errors of, 326 
 
 index of, 295 
 
 laws of, 295 
 
 of the eye, 308 
 Refractive apparatus of eye, 308 
 Retina, ansemia of, 262 
 
 anatomy of, 250 
 
 angeoid streaks of, 261 
 
438 
 
 INDEX 
 
 Retina, arteriosclerosis changes 
 of, 264 
 
 changes due to excessive light, 
 261 
 
 circulatory disturbances of, 
 262 
 
 contusion of, 261 
 
 cyanosis of, 262 
 
 detachment of, 267 
 
 diseases of, 252 
 
 embolism of central artery of, 
 264 
 
 ghoma of, 194 
 
 hemorrhages in, 263 
 
 hjrpersemia of, 262 
 
 inflammations of, see Retinitis 
 
 ischsemia of, 262 
 
 oedema of, 255, 261 
 
 ophthalmoscopic view of, 35 
 
 perivasculitis of, 264 
 
 physiology of, 251 
 
 pigment degeneration of, 266 
 
 rods and cones of, 251 
 
 subhyaloid hemorrhage of, 263 
 
 symmetrical changes at mac- 
 ula of, 261 
 
 thrombosis of central vessels, 
 265 
 
 vascular changes in, 262 
 
 vessels of, 34, 250 
 Retinitis, 252 
 
 albuminuric, 256 
 
 circinata, 261 
 
 deep, 255 
 
 diabetic, 258 
 
 electric, 261 
 
 gravidic, 257 
 
 hemorrhagic, 260 
 
 leuksemic, 258 
 
 metastatic, 260 
 
 nephritic, 256 
 
 of Bright's disease, 256 
 
 parenchymatous, 255 
 
 pigmentosa, 266 
 
 primary, 252 
 
 proUferans, 221, 261 
 
 punctata albescens, 267 
 
 renal, 256 
 
 secondary, 252 
 
 septic, 260 
 
 serous, 255 
 
 simple, 255 
 
 solar, 261 
 
 striata, 261 
 
 syphilitic, 259 
 
 uncommon forms of, 260 
 Retinochoroiditis, 182, 253, 259 
 
 Retinoscopic mirror, 321 
 Retinoscopy, 321 
 Retractors, lid, 7 
 Retrobulbar abscess, 81 
 
 neuritis, 275 
 Retrotarsal fold, 4, 92 
 Rodent ulcer of the Uds, 64 
 Rotation, centre of, 309 
 
 Salmon patch, 146 
 Salvarsan, 405 
 Schlemm's canal, 177, 199 
 Sclera, anatomy of, 158 
 
 diseases of, 158 
 
 inflammation of, 158 
 
 injuries of, 162 
 
 rupture of, 162 
 
 staphyloma of, 161 
 
 trephining of, 216 
 
 wounds of, 162 
 Scleral ring, 33 
 Sclerectomy, 208, 217 
 Scleritis, 158, 160 
 Sclerochoroiditis posterior, 185 
 Sclerotic, see Sclera 
 Sclerotomy, anterior, 208, 215 
 
 posterior, 208, 215, 269 
 Scopolamine, 402 
 Scotoma, 17, 183, 276 
 
 absolute, 18 
 
 annular, 17 
 
 central, 17, 185, 276 
 color, 18, 276 
 
 motile, 17 
 
 negative, 17 
 
 paracentral, 17 
 
 peripheral, 17, 183 
 
 positive, 17 
 
 relative, 18 
 
 ring, 17 
 
 scintillating, 292 
 Semilunar fold, 92 
 Sense, color, 10, 18 
 
 form, 10 
 
 fusion, 374 
 
 light, 10 
 Septum orbitale, 77 
 Sera, 406 
 Shadow test, 321 
 Shield, Buller's, 105 
 Shortsightedness, 331 
 Sideroscope, 224 
 Siderosis, 224 
 Sight, 10, 288 
 
 old, 313,353 
 
 second, 230 
 
 weak, 347 
 
INDEX 
 
 439 
 
 Signs used in ophthalmology, 
 
 Silver nitrate, 396, 399 
 Skiascopy, 321 
 Skin-grafting, 57, 130 
 Smoked glasses, 408 
 Snow blindness, 97, 261 
 Sodium chloride, 394 
 Spectacles, 349 
 Spectroscope, 283 
 Sphincter pupiUse, 164 
 Spring catarrh, 127 
 Squint, see Strabismus 
 Staphyloma, anterior, 161 
 
 corneal, 138, 150 
 
 equatorial, 161 
 
 posterior, 161, 185, 334 
 
 scleral, 161 
 Stenopseic disc, 341 
 Stereoscope, 376 
 Stimulating remedies, 395 
 Stovain, 404 
 Strabismometer, 373 
 Strabismus, 361, 362 
 
 alternating, 372 
 
 concomitant, 371 
 
 constant, 372 
 
 convergent, 372, 374 
 
 deorsum vergens, 372 
 
 diagnosis of, 372 
 
 divergent, 372, 378 
 
 etiology of, 374 
 
 external, 372, 378 
 
 internal, 372, 374 
 
 latent, 361, 384 
 
 measurement of, 373 
 
 monocular, 372 
 
 occasional, 372 
 
 paralytic, 362, 372 
 
 periodic, 372 
 
 sursum vergens, 372 
 
 sjTnptoms of, 374 
 
 vertical, 372 
 Stye, 43 
 Subconjunctival hemorrhage, 94 
 
 injections, 405, 410 
 Subhyaloid hemorrhage, 263 
 Suprachoroid, 182 
 Suprarenin, 404 
 Sutures, Gaillard-Arlt, 52 
 
 Pagenstecher's, 60 
 
 Snellen's, 54 
 Symblepharon, 117, 129 
 Sympathetic, exsection of superior 
 cervical ganglion, 218 
 
 inflammation, 188, 189 
 
 irritation, 189 
 
 SjTnpathetic ophthalmia, 188 
 
 ophthalmitis, 188 
 Synechia, annular, posterior, 168 
 
 total posterior, 168 
 SynechisB, anterior, 7, 137 
 
 posterior, 7, 166, 169 
 Synchysis, 220 
 
 scintiUans, 221 
 Syphilis, inherited, signs of, 148 
 Syringe, eye, 394 
 
 Tannic acid, 395 
 Tarsal cyst, 44 
 ligaments, 39 
 tumor, 44 
 Tarsitis, 41 
 Tarsorrhaphy, 57 
 Tarsus, 39 
 
 Tattooing of cornea, 154 
 Tear sac, 2, 67 
 Temporal pallor of disc, 276 
 Tenderness, ciUary, 8 
 Tenonitis, 82 
 Tenon's capsule, 78, 158, 357 
 
 space, 78 
 Tenotomy, 377, 381 
 
 limited or partial, 390 
 Tension, notation of, 9 
 
 of eyeball, 8 
 Test types, distant, 10, 315 
 for ilUterates, 13 
 for near vision, 14, 317 
 Jaeger's, 14, 317 
 Snellen's, 10, 315 
 Thiosinamin, 396 
 Thrombosis of cavernous sinus, 82 
 
 of central artery, 265 
 
 of central vein, 265 
 Tobacco amblyopia, 276 
 Tonometer, 9 
 Toric lenses, 350 
 Toxic amblyopia, 276 
 Trachoma, 113 
 
 acute, 115 
 
 bodies, 118 
 
 cicatricial stage of, 115 
 
 follicular form of, 114 
 
 forceps, 120 
 
 granular form of, 114 
 
 granules, 114 
 
 mild, 116 
 
 mixed form of, 114 
 
 operations for, 120 
 
 non-inflammatory, IIS 
 
 papillary form of, 114 
 
 simple, 115 
 
 treatment of, 118 
 
440 
 
 INDEX 
 
 Transillumination, 36, 195 
 Transilluminator, 36 
 Trephining of sclera, 208, 216 
 Trichiasis, 46, 117 
 operations, 48 
 Tropacocain, 404 
 Tropometer, 359 
 Tuberculin, 406 
 
 Tuberculin conjunctival test, 406 
 Tumors, intraocular, 194 
 
 Ulcer op the cornea, see Cornea 
 
 rodent, of the lids, 64 
 Undine, 394 
 Uraemic amblyopia, 258 
 Uvea, 164 
 Uveal tract, 164 
 
 diseases of, 188 
 Uveitis, 178, 188 
 
 anterior, 146, 160 
 
 metastatic, 181, 187 
 
 plastic, 179, 189, 190 
 
 purulent, 192 
 
 serous, 190 
 
 sympathetic, 180, 188 
 
 Vaccines, 406 
 Vasa vorticosa, 182 
 Venae vorticosse, 182 
 Vernal catarrh, 128 
 Vision, acuteness of, 10, 11 
 
 binocular, 359 
 
 blue, 283 
 
 central, 10 
 
 color, 18, 282 
 
 colored, 283 
 
 direct, 10 
 
 distant, 10 
 
 field of, 14 
 
 alterations in, 16 
 contraction of, 16 
 
 Vision, field of, defects in, 17 
 extent of, 16 
 limitations of, 16 
 pathological alterations 
 
 of, 16 
 tests for, 14, 15 
 
 green, 283 
 
 indirect, 14 
 
 near, 10 
 
 peripheral, 10, 14 
 
 red, 283 
 
 white, 283 
 
 yellow, 283 
 Visual angle, 10 
 
 area of cerebral cortex, 288 
 
 impressions, 252, 288 
 
 line, 309 
 
 paths, 175, 289 
 
 purple, .251 
 Vitreous, 220 
 
 abscess of, 186, 223 
 
 anatomy of, 220 
 
 diseases of, 220 
 
 fluid, 220 
 
 foreign bodies in, 223 
 
 hemorrhage into, 222 
 
 opacities of, 221 
 Vossius' ring, 245 
 
 Watery eye, 68 
 Wernicke pupillary reaction, 291 
 White's ointment, 398 
 Word-blindness, congenital, 281 
 
 Xanthelasma, 63 
 Xanthoma, 63 
 Xerosis, 117 
 X rays, 64, 122, 407 
 
 Zinc sulphate, 395 
 Zoster, 42