^ THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA LOS ANGELES OPHTHALMOSCOPIC DIAGNOSIS OPHTHALMOSCOPIC DIAGNOSIS BASED ON TVPICAL PICTURES OF THE FUNDUS OF THE EYE WITH SPECIAL REFERENCE TO THE NEEDS OF GENERAL PRACTITIONERS AND STUDENTS BY Dr. C. ADAM ASSISTANT AT THE KGL. INIV. -AUGENKLINIK, BEKLIN TRANSLATED BY MATTHIAS LANCKTON FOSTER. M.D. OPHTHALMIC SURGEON TO THE NEW HOCHELLE HOSPITAL: MEMBER OF THE AMERICAN OPHTHALMOLOGICAL SOCIETY; MEMBER OF THE AMF.RICAN ACADEMY OF OPHTHALMOLOGY AND OTO-LARYNGOLOGY WITH 86 COLORED PICTURES ON J>8 PLATES AND 18 ILLUSTRATIONS IN THE TEXT ^ THE MEDICAL ART AGENCY Herai.I) Sgi arf. BcM.niNG 14i-14.,i WEST .'iihii STREET NEW YORK ( 1 TV REBMAN COMPANY SOLE AGENTS Copyright, 1913, by REBMAN COMPANY New York All Rights reserved PRINTED IN AMERICA Co THE MEMORY OF MY HOxNORED TEACHER, JULIUS V. MICHEL HI Preface This book is dedicated to tlie nieniory of Jidlus r. Michel, to wlioin is due the credit of its conception, its purpose, and its arrangement. I have sinijjly followed out liis idea in bringing into bold relief the relations that exist between diseases of the eye and those of the general organism. He had the satisfaction, which falls to the lot of few, to see the ideas, for which he had fought all his life, receive general recognition in his old age. His views concerning the material part played by tuberculosis in the etiology of diseases of the eye, as well as those in regard to the diagnostic importance of changes in the vessels of the fundus, are now generally accepted as correct. To a much less degree is this true of his theory concerning myopia, and the writer is well aware that he may excite disj)ute when he undertakes to present this conception in the present book. In the title the word "Atlas" has been intentionally avoided. l)ecause it emphasizes the illustrations; the words "Ophthalmoscopic Diagnosis" have been chosen instead in order to indicate that the real purpose of the book is to be a systematic guide to diagnosis, and that the illustrations are intended to serve simply as aids in the carrying out of this purpose. The manner in which the text has been written and arranged has also been made sub- servient to this point of view. A glance at the Table of Contents will show that the ophthalmoscopic pictures of hemorrhages, white spots, black spots, etc., have been utilized solely as a means of classification, and that the attemjit has been made to bring out the diagnosis, and to impress the clinical pictvire through the symptoms there depicted. The earlier text-books on ophthal- moscopy, such as those by Jaeger, Mauthner, Schiceiggcr, Dimmer, Sehmidt- Jtimpler, and others, started from the clinical concejitions of disease, and porti'aved these, with their details and symptoms. The first to take the ophthalmoscopic symptom as a basis for classification — at least in literature, for doubtless many besides ourselves had ])reviously used it in teaching — was Ehchnig, in his article on ophthalmoscopic differential diagnosis in Axenf eld's text-book. I have followed his lead in many places where his method of presen- tation seemed to be suitable for my purpose. Special attention has been paid to those diseases of the eye that are related to general diseases, and the greatest consideration has been given to the varied needs of the general practitioner, the neurologist, the gynecolo- vii vui gist, and tlu' sypliilolo^ist, in tlio ni.'inncr in wliicii tiiey arc presented. The reader will find in tlie Index not only the individual symptoms, l)iit also con- nected with them tile f^^neral diseases of wiiieii tliev form the oeidar sis^ns. Pathology is entered into only so far as seemed advisahle for the explana- tion of the ophthalmoscopic pictures. Brief space is likewise given to prog- nosis and treatment. Alost of the pictures were taken with the aid of Thonicr's demonstr.ition oplitlialmoscope, hut they ii.ivi' been reduced about two tliirds in size for i-cproduction until they ])resent the inverted image magnified about ten times. I cannot conclude without expressing my obligations to those who have helped me in this work. Above all I wish to show my gratitude to Prof. Krueckmann, who undertook the great labor of revising the manuscript, and to thank my colleagues who have been of great assistance by selecting and furnishing me with patients. Table of Contents PAGE The Technique of the Examination with the Ophthalmoscope 3 I. Invirled Imatje 3 1. Focussing upon the Papilla 3 •2. The Correct Distance -t 3. Correct Accommodation 5 4. The Question of Wearing Glasses 6 5. Avoidance of Reflexes from the Lens and Cornea 6 6. Indistinctness of the Image 7 7. Incompleteness of the Image 7 8. Investigation of the Macula 7 9. Examination of the Periphery S II. Upright Image 8 Determination of the Differences of Level in the Fundus (Paralactir Displare- ment. Perspective Displacement. Determination of the Refraction) 9 Place and Size of a Lesion in the Fundus lU The Dilatation of the Pupil for the Purpose of an Ophthalmoscopic Examination. . 10 The Normal Papilla and the Normal Fundus i j AxATOMiCAL Review 1 j The Ophthalmoscopic Picture of the Xormal Papilla 17 Form, Color 1 " Margins 18 Excavation of the Papilla 18 Vessels 23 Arteries and Veins 22 Venous Pulse 2:i Vascular Anomalies -3 The Fundzis OcuH 2i Types of the Normal Fundus 21 Retinal and Chorioidal Vessels 2.) Retinal Reflexes ; . . . . ^G Macula -(>' Conus and Staphyloma 33 Differential Diagnosis of the White Rings and Crescents to be Found in the Imme- diate Vicinitv of the Optic Xerve 33 The Conus 34 The Staphyloma 37 The Conus Inferior 39 Peripapillary Atrophy of the Chorioid 39 The Halo 40 Medullated Xerve Fibers 40 ix X PAOE Atrophy of the Optic Nerve 5i Differential Dia);Iul^i^ of the Xarious I'Drnis of .\tn)])liy 51 Atrophic Excavation 51 Total Atkophy 53 1. Simple Atrophy 53 2. Nutritional .Vtrophy 55 ,Vtro|)liy Due to Oeeliision of the .Vrteries 55 3. (jlaiieoniatons .Xtrojjhy 55 4. Neuritic Atrophy 57 5. Atrophy of the Papilla in Retinitis I'ijjnuntosa 58 Pahti.m., Teimi'Ohai,, ,\tiioi']iy of the Optic Nkiive 58 Neuritis, etc 7i I. Keuness of the Papilla by Itself 71 II. Optic Neuritis ^- Differential Diagnosis between Optic Neuritis, Choked Disk ami Pseudoneuritis.. 73 Course of Optic Neuritis 71 What Etiological Conrliisions can be Drairn from the Ophthnlmoscojiic Picture of an Optic I\'euritis 75 1. Syphilitic Optic Neuritis ( Neuro-retinitis sjjecilica) 75 2. Tuberculous Optic Neuritis 76 3. Albuminuric and Diabetic Optic Neuritis 76 i. Arteriosclerotic Optic Neuritis 77 5. Otogenous Optic Neuritis 77 6. Optic Neuritis Caused by Abscesses in the Orbit and Emiiyeinas of the Accessory Sinuses "i^ 7. Sympatlietic Optic Neuritis 78 Other Forms of Optic Neuritis 78 III. AxiM. Optic NErniTis (Neuritis fascicuM |)a|iilloiii.iciilaris; toxic neuritis; retro- liulliar neuritis) '8 Demonstration of a Central Scotoma by the Aid of //./i/;' Cliarts 79 I^". CiioKEU Disk '** Uliat Etioloi/ical Conchisioii.i can l>c Urairn from the Ophlhalmoscoiiic Picture of Choked Disk 81 Unilateral Choked Disk 81 Bilateral Choked Disk 81 Tumors 83 Hemorrhages on the Papilla 83 Wounds of the Optic Nerve 83 Vessels of the Retina 97 Preliminary Remarks on the Anatomy ^'^ Changes in the Vessels of the Retina ^8 Elaboration of the Above Summary ^8 A. The Caliber ^^ 1. Contraction • • ^8 2. Dilatation '^^^ a. Uniform Dilatation of the Veins and Arteries 100 b. Veinous Hyperemia with the .\rteries Normal or Contracted 101 3. The Differences in the Proportional Sizes of the Arteries and of the Veins.. 101 4. Unevenness of Caliber xi PAGE B. The Color of the Vessels 102 Color of the Blood Column 103 Color of the Vessel Wall 10-2 I Accompanying Stripes lOi Transformation into White Cords 103 Deposits in or over the Vessels 103 C. Changes in tlie Nnnilicr of the Vessels 104 D. The Course of the Individual Vessel 105 E. The Keflex 105 F. Phenomena of I'ulsation lOG \'enoiis and Arterial Pulse 106 Retina ill A. I'ltEI.I.MlNAUV KkmAHKS ON THE AnATOMY Ill The Nutrition of the Retina 113 B. General Diagnosis 113 Ophthalmosco])ic Differentiation of Diseases of the Inner and Outer Layers of the Retina and of the Chorioid 113 The Position of the Changes in the Retina 113 Retinitis , Ill Are Alterations in the Pigment Epithelium Present or Not? Ill C. Special Diac.nosis II j Retinal Lesions Which Exliibit Xo Alterations in the Pigment Epithelium (Dis- eases of the Inner Layers) 11 j I, Hemorrhages 110 a. Hemorrhages as the Only, or the Most Important, Change in the Retina IK! Is a Differential Diagnosis Possible, Based on These Findings? 117 Thrombosis of the Main Trunk of the Central Vein 117 The Causes of Retinal Hemorrliage 118 Differential Diagnosis 119 Recurrent Hemorrhage into the Vitreous 119 b. Hemorrhage into the Retina as an Accompanying Syinptiau of Disease of the 0])tic Nerve 1-0 II. While Spuls in the Fundus 1;25 Qucs/lon I. Is the White Spot in the Retina, or in the Chorioid? (Differential Diagnosis lietween Retinal and Chorioidal Spots) 135 1. Trustworthy Sym])toms 136 2. Adjuvant Symptoms 126 Cases in which the Diagnosis is Difficult 127 Question 2. Is this a Case of MeduUated Nerve Fibers or Not? 128 Diagnosis and Importance of Medullated Nerve Fibers 128 Question 3. Of What Nature are the Spots in the Retina? 128 Question ). In How Far Can the Pathological Construction of a Spot be Determined fnim the Ophthal- moscopic Picture? 129 XII PAGE nitfiTcntial Diafriiosis of White Spots from a PatliolDgical Stanclpoint (Connective Tis- sue; CKdenia; Varicose 'Ihickcning of the Layer of Nerve Kihers; Fatty Degen- eration ; I'ilirinoii.s Exudates) 129 In How Far Can a Conclusion he Drawn from the Oplithalmoseopic Picture Concerning the Etiology of White Spots? Differential Diagnosis of White Spots from the Etiological Stand;-oi:;t 131 a. Bedridden, Fehrile Patients ( Ketir.itis Teptica) 13:2 b. Xoufehrile Patients 133 1. lietinitis aibuminuriea 133 ■J. Ketinitis ilialietica 134 3. Ketinitis leucocytliainica 135 4. Ketinitis ana?inica 135 5. Retinitis syiihilitica 135 6. Retinitis proliferans 133 7. In Cases of Choked Disk 136 III, Diffuse Oiiacilii of the Jirllim 149 a. Without Great Differences of Level 149 1. CEdema 149 ■2. Diffuse Infiltration with White Blood C)rpuscles 150 3. Necrosis of the Inner Layers of the Retina 150 4. Vasomotor Di.'turhance with Transudation 151 5. Flat Detachment of the Retina 151 b. Diffuse Opacity of the Retina with Marked Differences of Level 152 1. Gibhous Detachment Caused by an Exudate 152 2. Detachment of the Retina Caused liv a Tumor of the Chorioid 152 3. Glioma cf the Retina 153 Concerning tlie Prognosis as to Life of Diseases of the Retina and Cliorioid 153 Chorioid 167 Prcliminiirii Remarks cii the A ikiIo-kii 167 General Diagnosis of Diseases of the Chorioid, so far as They are Caused by Diseases of the Vessels 168 Etiology cf Chorioid;ti3 170 Diagnosis 173 .(. Ccneral Dinflnosis 17:2 1. The Position of the Lesions in the Chorioid 173 -'. The Sort of Pigmentation and Depigmentation 173 3. Are Changes Present in the ^'essels or Not? 173 1. The Form of the Change 173 5. Differences of Level 173 B. SjirrinI Dkninosis 174 a. Changes in the Chorioid and Retina Which Occur Chiefly or Exclusively in • the Peri])hery 174 CoUerlions eif Pitjment 174 1 . Bone Corpuscles, etc 1 74 2. Masses of Pigment, \\'hich are often Annular 175 3. Snuff Fundus 175 4. Isolated Spots of Pigment 175 XIU PAGE Depigmentation in the i'erijilieri/ 175 1. Discrete Pigmentation 175 2. Superficial Pigmentation 176 b. Changes in the Chorioicl in the Region of tlie Macula 176 1. Arteriosclerotic Changes in the Macula 176 2. Changes in the Macula Caused by Contusions, or by the Presence of a Foreign Body in the Eye 177 3. Changes in the Macula Caused by High Myo])ia 177 4. So-called Coloboiua of the Macula 177 c. The Changes in tlie Chorioid about the Optic Nerve 177 Peri]>apillary Sclerosis of the N'esseN 178 Hujitures of the Chorioid 178 Coloboma of the Chorioid 178 d. The Disseminated Form of Chorioretinitis 179 Fresh Spots 1 79 Old Atrophic Sjiots 179 1. Atrophic Spots Without Visible Changes in the Vessels 180 2. Atrophic Spots with Changes in the \'essels 180 Changes in the Chorioid with Differences of Level 181 List of Figures in the Text FIG. PAGE A. — The Correct Distance 5 f5. — Correct Accommodation 6 C. — Examination of the l^ft Eye 8 D. — Microscopic Section Through a Normal Optic Nerve IG E. — Small Excavation in the Temporal Part of the Papilla 19 F. — Schematic Drawing of the Fundus, Upright Image 20 G. — Variety in the Courses of the Retinal Vessels 21 H. — Distribution of Pigment 21 I. — Head of the Optic Nerve in Myopia, after Ftichs 35 J. — Schematic Sketch to Show how the Papilla is Caused to Appear out of Drawing in High Myopia 38 K. — In this Case the Ectasia does not I.ie Exactly at the Posterior Pole, but rather Below it 38 L. — In this Case the Ectasia Lies to the Nasal Side of the Posterior Pole, so that the Pa- pilla Occupies the Bottom of its Cavity 38 M. — Glaucomatous Excavation 56 N. — Deep Physiological Excavation 56 O. — Neuritis Optica 77 P.— Choked Disk 82 Q. — Anatomy of the Retina, after Greeff 112 R. — Total, Funnel-shaped Detachment of the Retina 153 XV List of Plates PLATE FIG. PAGE I. 1. Normal Fundus of the Unifonn, Sti|ipli-il Typo -8 I. -2. N'ormal Fuuthis of the Tessehitecl Type, with Xiimerous Reflexes from the Retina -« 11. 3. Alliinotie Fundus 30 III. I. Coiius I'emporalis *^ III. 5. Conus Temporalis; Supertraetion in "Sehool" Myopia H IV. (i. Commencing Staphyloma Postieum in "Congenital" Myopia 46 IV. 7. Crescentic Sclerosis of the Chorioid Due to Arteriosclerosis 46 V. 8. Conus Inferior; Partial Alhiuism 48 V. 9. MeduUated Nerve Fihers 48 VI. 10. Simple White Atrojihy of the Optic Nerve Bi VI. 11. Simiile Gray Atrojihy of the ()])tic Nerve t'i Vll. l-\ Atrophy after Intlannnation of tlie Ojitic Nerve, Neuritie Atrophy ()4 VII. i:i. Atrojihy of the Optic Nerve after Clioked Disk (U VIII. 14. tllaucomatous Excavation and Atrojiliy : 66 VIII. 15. Large Physiological Excavation uminuric Optic Neuritis ( All)uminuric Choked Disk) 88 XI. -21. Optic Neuritis Undergoing Involution 88 XII. 22. The Optic Nerve in a Case of Sinus Tliromljosis Couijilicating an Otitis Media ^0 XIII. 23. Conuuencing Choked Disk 9- XIII. 2i. Conunencing Choked Disk 9- XIV. 25. Old Choked Disk with a Very Ahundant Develo])inent of Vessels 94 XIV. 26. Choked Disk at its Acme 94 XV. 27. Occlusion of the Central Vein of tlie Retina (Aiiojilexia Saiiguinea Retina') 1J2 XV. 28. Occlusion, or Thromhosis, of a Single Vein of the Retina 122 XVI. 29. Foreign Body in the Retina and Chorioid 1-H XVII. 30. Retinitis Albuminuriea 138 XVII. 31. Retinitis Albuminuriea 1-58 XVIII. 32. Neuroretinitis Albuminuriea '40 XVIII. 33. Neuroretinitis AUmminurica Ciravidaruin wilh net.u-luuent of the lietina.. 140 XIX. 34. Very Severe Neuroretinitis Alliuminurica 142 XIX. 35. Neuroretinitis Diabetica 142 XX. .36. Retinitis Proliferans in Diabetes 144 XX. 37. Retinitis Proliferans in Syjihilis 144 XXI. 38. Retinitis Luetica 1 i'' XXI. 39. The Same Case Six Weeks Later 1 16 XXII. 40. Sympathetic Optic Neuritis and Cliorioiditis 148 XXTI. 41. Colloid Deposits on the Vitreous Lamella of the Chorioid 148 XXIII. 42. Retinitis Luetica l-5'> XXIII. 43. Commotio Retina-, or Berlin'^ 0])acity 156 XXIV. 44. Sudden Total Occlusion of the Central Artery, the sivcalled Embolism.. 158 XXIV. 45. Occlusion of the Central .Artery in a Later Stage 158 XXV. 46. Flat Detachment of the Retina 1«0 xvii xviii PLATE FIG. \.\V. 17. XXVI. ■IS. XXVI. lil. XXVll. 51). XXVlll. :a. XXVIII. 5-'. XX I \. .5:5. XXX. 3i. XXXI. oo. XXXI. jli. XXXII. 57. XXXIII. 5S. XXXIW 59. xxxi\-. (iO. XXXI \. (U. XXXIV. G2. XXXV. 63. XXXV. 61. XXXVI. 65. XXXVI. 66. XXXVII. 67. XXXVII. 68. XXXVIII. (;<). XXXIX. 70. XXXIX. 71. XL. 7-'. XL. 73. XLL 74. XI.I. 75. XLII. 76. XLIL 77. XLIIL 78. XLIV. 79. XLV. 80. XLV. 8L XLVI. 8-2. XLV I. 83. XLVIL 84. XLVIL 85. XLVI 1 1. 86. I'AGE Partial Flat Dctaohmcnt of the lictiiia 160 Large CJilibous nctailiiiiciit of tin- Uctiiia liiJ Detachment of the Hetina Caused by a Tumor of the C'liorioid 1(U Small Glioma of the Uetiiia Kit Hetinitis I'ipmentosa, or I'ifimeiil Degein-ralioii of the lietiiia 181. Secondary Hetiuitis I'lgnieiitosa ISt Grossly I'ifrnuTitcil I'liiulus of Hereditary .Sy|hilis l^a Schematic Pictures of Diseases of the Chorioidal Vessels 188 The so-called Pepper and Salt I'uiidus of Ileret in the Periphery.. 210 Extensive so-called Chorioretinitis Disseminata with Scleroses of the \'es- scls of the Chorioid 212 So-called Chorioretinitis Disseminata with Scleroses of the Vessels of the Chorioid 212 Chorioretinitis Tuberculosa 211 Chorioretinitis Tiiberculosa 216 Healed Inflammatory (Tuberculous) Spot in the Macula 218 Fundus of the Eye in .-\cute Miliary Tulierculosis 218 Extensive Rupture of the Chorioid with I)evel()]]mcnt of Cormective Tis- sue in Places --0 Rupture of the Chorioid 220 Coloboma of the Chorioid 222 Extensive Coloboma of the Chorioid 222 Normal Fundus of a Rabbit 22i Alphabetical Index of Figures on the Plates The Numerals indicate the Numbers of the Colored Figures Alliinisni. partial, 8 Alluiiniiuiria, liil, 77 neuritis, ai'c Neuritis neuroretiiiitis. 32, 33, 34 occlusion of tlic central vein, '27 retinitis, 30, 31 Alliuniinuric choked disk, 30 AjiO]ilexia -.anguinea retina, 27 Arteriosclerosis, 7, 59-C'-', 64, 65, 67 macula, 59-62, 64 neuritis, xee Neuritis occlusion of tlie central vein, 27 Atrophy of the optic nerve, after choked disk, 13" after occlusion of the central artery, 16 glaucomatous, 14 gray, 11 in retinitis pigmentosa, 51 multiple sclerosis, 17 nenritic, 12 retinitic, 51 simple, 10, 11 syphilis, acquired, 75 syphilis, inherited, 56, 58 tahetic, 11 temporal paleness, 17 white, 10 yellow, 51 Birling o]iacity, 43 Central artery, occlusion of, 16, 39 sudden, 44, 45 Cherry red spot, 44, 45 Choked disk, albuminuric, 20 abundant development of vessels, 25 i.t its acme, 26 atrophy, see Atrophy ditl'iise, 26 hemorriiages of retina, 26 iiKi)>ient, 23, 24 knob-shaped, 2j Chorioid. changes of, 51-85 albuminuria, 69, 77 arteriosclerosis, 59-62, 64, 65, 67 colobonia, 84, 85 diffuse, 67, 68, 76, 77 heredosyphilis, 68 macula, 64 myopia, 6, 70-73 peripapillary, 65 ]ieripheral, 60, 75 rupture, 82, 83 schematic pictures, 54 syphilis, 66, 74, 75, 76 tuberculosis, 78-84 vessels, 64-77 Chorioretinitis, 76-80 albuminuric, 69, 77 Chorioretinitis, arteriosclerotic, 59-62, 64, 65. 67 heredosyphilitic, 53, 55-58, 63, 68 myopic, 70, 73 jiigmented, 51 proiiferans. 82 sympathetic, 40 syphilitic, 60, 74, 75, 76 tuberculous, 78-84 Cilioretinal artery, 4 Coloboma of the chorioid, 84, 85 Commotio retinae, 43 Connective tissue, chorioid, 82 retina, 36, 37 Connective tissue rings, 1, 2 Conus inferior, 8 temporalis, 4, 5 Depigmentation, 55, 57, 58, 63 Detachment of the retina, arteriosclerotic, 47 caused by a tumor of the chorioid, 49 flat, 46 glioma, 50 in nephritis gravidarum, 33 large gibbous, 48 partial flat, 47 Develo]inient of coiuiective tissue, 82 Diabetes, colloitl deposits on the vitreous lamel- la, 41 liemorrhage. 35 neuroretinitis, 35 varicosities. 36 white spots, 35, 36 Excavation, glaucomatous, 14 physiologic, 15 Foreign bodies in the retina, 29 Fundus, albinotic, 3 in myojiia, 70-73 normal, 1, 2, 3 sti])pled, 1 tesselated, 3 Glaucoma, 14 Cilaucomatous atrophy, 14 excavation, 14 halo, 14 Glioma of retina, 50 Halo, 14 Intravascular spaces, 2 Lamina cribrosa, meshes, 5, Macula, changes in, myopic, reflexes, 2 senile, 59-63 stT, 30, 34 15 70-73 XX McthiUated nerve fibers, !) in the rahhit, H(i M(■IliIl}riti^. sy])liilitic, atrojihy, 58 tiilnTC-iiloiis, neuritis, 81 Miliary tuherculosis, 81 iliiltiiile si-lerosis, see Atrophy Jlyopiiu, aequirecl (school), i, 5 conjrenital, H diseases of the vessels i)f the chorioid, 70-73 selereetasia, 7;5, 85 sta|)hyloma iiostiemn, (>, 70-73 venim, 73 Weiss-Olto shadow-ring, 73 Naeviis of retina, 31 Nephritis, sec .\lbnniin\iria Neuritis, see tilso Neuroretiiiitis alhuminurie, -'0 arteriosclerotic, 2\ defreneralion of retina, JO lieniorrhages of retina, -0 in otitis media, JJ interstitial, 18 migration of pigment, -21 miliary tnhercniosis, 84- jieripajiillary oedema, 18, 2-2 svpliilitic. 18 tuhereulous, 19, 81 undergoing involution, 21, 37 Neuritic atro|iliy, IJ Xeuroretiniti^, alliuminurica, 3:?, 33, 3i, 39 liiabetic, Sj, 3(j sjinpathetic, -10 Occlusion of the central artery, 45 Otitis neuritis, 22 Papilla, normal, 1, 2. 3, 15 transversely oval, 8 Peri]iapillary (inlema, see Neuritis Pigment, degeneration, 51, 52 migration, 75 rings, 1 Rabbit, mcdullated nerve fibers, 22i Retina, allniininuria, 20. 31, 32. 33, 34, 69 aneiiri^^m, 3(i atrophy of optic nerve, see Atrophy changes in arteriosclerosis, 21, 27, 28, 44, 45, ()7 diabetes, 34, 36 heredosvphilis, 56-58 s\7>hilis', 12, 18. 27, 28, 37, 38, 39, 42, 44, 45 congestion through nedema, 22. 78 through niedullated nerve fibers, 9 connective tissue, 3(i, 37 degeneration in neuritis, see Neuritis detachment, 49 disajipearance of vessels, 36, 56 dis|)ro])ortion of vessels, 24, 26, 28, 32 extravasation of vessels, 33 exudates, 38, 39 fatty degeneration, SO Retina, foreign bodies, 29 glioma, 50 hemorrhage, 27, 2ii, 31 in diabetes, 35, 36 striated, 32 injuries, 29, 43, 82, 83 migration of pigment, 12, 16, 21 , navus, .31 normal, 1-9 occlusion, 16 (Tdema, 9, 31, 42, 44 reflexes, 2, 30 retinitis pigmentosa, 51 vessels, i6-58 white spots in albuminuria, 30 in diabetes, 35, 36 Retinitis, see also Neuroretinitls albuminurica, 30, 31 pigmented, 51 jiroliferans, 36, 37 se<'oiuiary iiigmented, 52 syphilitic. I-' Schematic ]iictures of the diseases of the chori- oidal vessels, 54 Scleral ring. 1, 2 Scleral vessels, 84, 85 Sclerectasia, 73, 85 Sclerosis, see Retina uiiil Chorioid Senile changes in macula, 59-62 Snuff fundus, 63 Stajihylonia jjosticum, 6, 70-73 verum, 73 Stipjiled fundus, 1 Supertraction crescent, 5 S3^llpathetic inflammation, neuritis, 40 white spots, 40 Syphilis, atrophy of the optic nerve, 12, 75 "cordlike bundles of connective tissue, 37 diseases of the vessels of the chorioid, 66, 74, 75, 76 diseases of the vessels of the retina, 38 inherited, atrophy of the optic nerve, 56-58 depigmentation, 55, 56, 57, 58 diseases of the vessels of the chorioid, 58, 68 diseases of the vessels of the retina, 56-58 finely pigmented fundus. 63 grossly jiigmented fundus. 53 l)e))per and salt fundus. 55 snuff fundus. 63 occlusion of the retinal artery, 38, 39 retinitis. 42 Tem])oral paleness. 17 'iesselated fundus, 2 Thrombosis of the central vein, 28 '1 uberculosis, chorioretinitis, 78-84 Vena centralis, 27, 28 Vortex veins, 3 Weiss-Otlo shadow-ring, 73 Preliminary Remarks on Technique The Technique of the Examination with the Ophthalmoscope cannot be taught in full detail in such a book as this, but a few suggestions may be of aid to those who are inexperienced. I. INVERTED IMAGE 1. Focussing upon the Papilla. The light should be placed behind and to the side of the patient, so that it will not shine into his eye. The complaint is heard very often in every class in ophthalmoscopy that the student can focus quite well upon the papilla of the left eye of the patient, but not upon that of the right. The reason for this is that the patient obeys too literally the customary direction, that he should look at the corresponding ear of the observer. The object of this direction is to cause the patient to look past the eye of the observer, or the mirror, at a certain distance, i.e., 15 cm, with his own eye slightly inclined toward his nose, in order that the papilla, which lies to the nasal side of the macula, may confront the observer. But when the physician holds the mirror before his right eye, the distance between it and his right ear is considerably less than the requisite 1.5 cm: it is a hand- breadth, some 10 cm too short, while the distaiice from the left ear to the mirror is about right. It is therefore necessary that on the side on which the phA'sician holds the mirror the patient should look not at the car of the observer, but ])ast it at the distance of about a handbreadth. in order to bring his papilla into view. Furthermore, it is not advisable to have the patient look at the ear of the observer, because he then accommodates, and a contraction of the pupil accompanies acconnnodation : therefore it is better, even when the patient is sitting on the opposite side, to direct him to look not at the c;ir, but past it, as though at an object in the distance. The direction usually given should therefore be made more precise, so as to read: In order to present his papilla the patient is to look at a distance past tin- ear of the observer corresponding to the eye that is being examined; if the latter is on the side on ichirh the phi/sician holds the mirror, he shoidd look about a handbreadth aicaii from the ear, if it is on the other side, the line of i-ision should pass close to the ear. 3 The correct presentation of tlie pajiilla is a matter of tlie f^reatest iinpor- tjince, althougli it is generally uiulervahied by beginners. It is perhaps the most importiint point connected with the examination, for it may be said without exaggeration that in about three quarters of all the cases a failure on the part of anyone using the opiithalmoscope is to be ascribed to an incorrect, or inexact presentation of the papilla, or to an incorrect, or inexact direction to the patient where to look. Let it once be realized that the retina comprises an area of several square centimeters, that within that surface the papilla is only a minute point, not much larger than the head of a pin, and it will i)e appreciated that a considerable degree of accuracy is necessary to properly present this point in tlie relatively large surface. Hincc it should be tlic rule in nil cases in zs.'hich the attempt to see the papilla is not irnmediatel// successful, to interrupt the examination and to ascertain first of tdl -iciutlicr the position of the patient's ctjc is correct. After the patient has been told in what direction to look the observer at first closes the eye which is not :it the ophthalmoscope and throws light into the eye of the patient without the iiiter]>osition of a lens. By doing this he learns two things: 1, whether the refractive media are clear, or opacities are [)rescnt in the cornea, lens, or vitreous, which may interfere with the examination ; and, l!, whether the papilla is actuall}' before him. If the patient presents his papilla cori'ectly the pupil does not appear to be as red as it otherwise does, but is of a whitish yellow, Ixcause the tone of its color is determined by that of tlie papilla. When this has been ascertained to be the case a lens is placed before the eye and the observer tries to obtain a sharply- defined image of the papilla. To attain this end 2. The Correct Distance between the optical systems, eye — lens — ej-e, is of paramount importance. When a +13 D lens ^ is used the distances are as follows: The total distance between the physician and the patient is approximately 40 to \h cm (see Fig. A in the text), of which 7 cm are between the patient and the lens, 32 to 37 cm between the lens and the physician. This is pro- vided that both the physician and the patient are emmetropic. If either one f ^ The strenprth of a convex lens may be ascertained in a very simple manner b.v producing the picture of any source of light upon a piece of paper by means of the lens. The distance at which the latter must be hold from the paper in order to ob- tain a sharj^ly defined image corresponds in general to the focal distance, which is measured in centimeters. Then it is only necessai-y to divide 100 by this number (100 cm ^ 1 m; the lenses are numbered according to the metric system) in order to learn its strength in diopters. If the image is sharply defined at the distance of 100 5 cm the lens is r= 20 diopters strength. or both have over 4 D of myopia the pliysician must come closer; if either cne or both are quite hypermetropic the distance must be somewhat greater. We must proceed in a manner similar to that employed in tlie use of a micro- scope. First comes the gross presentation at the distances given above, and then comes the micrometer screw, by the movement of the head of the physician a little backward and forward until the image is sharply defined. In high degrees of hypcrmetropia, like such as are present after removal of the lens for cataract, the observer must increase the distance quite a good Fig. a. deal in order to obtain a distinct image of tlie fundus (see Detaclmient of the Retina, page 1-52). Next to faulty accommodation, incorrect distance is the most important cause of iiuiistinctness of the image (see under (>)• 3. Correct Accommodation. The image of the fundus produced by the convex lens lies in front of the latter at the distance of its focal point. 7 cm in front of it, at point B in Fig. U. The physician must focus his eye upon this point. This is done most easily when the point is at his ordinary reading distance, "2.5 to 30 cm, and the accommodation used for reading is called into activity. But begin- ners usually try to see the image in the ej'e of the patient, accommodate incorrectly, and so cause the image to be indistinct. An emmetrope can overcome this difficulty by substituting for the necessary accommodation a convex glass of from 2 to 4 D, preferably behind the mirror. A myope lessens his correcting glass by the same amount, so that myopes of less than 4 D do best without any correcting glass, while a hypermetrope has to increase the strength of his glass. It is well for the {)h_vsieiaii to euiaiieipnte iiiinself from tlie need of tliis glass by prolonged praetice. Anotiier trick is to have someone hold the ti|) of his finger at the place where the image must be formed, i.e., T em in front of the lens; the observer fixes his eyes on the tij) of the finger and maintains iiis ucconmiodation when it is witlulr.iwii. A corollary to what ha.s been said is tliat the observer must be certain in regard to his own refractive condition. 7cm~ Z5-30cm. Fig. B. 4. The Question of Wearing Glasses during an ophthalmoscopic examination has been answered by the above ri'inarks. As the image lies in front of him at the distance of 25 to 30 cm, the ordinary reading distance, the physician wears the same glass that he uses to read witli, particulaily if he is presbyopic. The most convenient way is to jilace a glass of the jjroper strength behind the mirror. 5. Avoidance of Reflexes from the Lens and Cornea. These reflexes can never be wholly avoided, even by the most expert. The student nnist learn to place them so that they do not fall directly on the place under observation. He may partially succeed in doing this by moving the lens a little to the right or left, so as not to look directly through its center, or by holding the lens in a slightly oblicjue jjosition. Much is won when he learns to look past the reflexes, for the disturi)ance they cause is due not only to the fact that they cover the image, but also to the fact that they distract the attention and consequently excite a faulty acconnnodation ill the eye of the observer. Sometimes the reflexes come from other sources of light ; this may be guarded against by seeing that the only light in the room is the one used for ophthalmoscopy, and that this is placed obliquely behind the patient, so that the eye to be examined is altogethei- in the shade. Finally, the lens itself must be perfectly clean, for a dirty lens increases enormously the reflexes that appear. 6. Indistinctness of the Image. AfttT sicrlit has huun caufrlit of the jiapilhi it often appears to be very indistinct. This may be due to a variety of causes. Cause 1. Tlie jiliysician or the patient may have high degree of astigmatism, or of some other error of refraction. 2. The distance may be incorrect. 3. His accommodation may be faulty. 4. Opacities may be present in the refractive media. 5. Tlie indistinctness may be due to disease of tlie optic nerve, retina, etc. Bemcdy He must therefore know the re- fraction of l)oth liimself and the pa- tient, and may need to correct it. Given under 2. Given under 3. Therefore lie throws light into the eye without using a lens before trying to see the fundus. The beginner should not make this diagnosis until he is positive that the cause lies neither in himself nor in his technique. 7. Incompleteness of the Image. If only a j)ortion, Init not the whole, of the papilla comes into view, the examiner moves himself toward the side which he wishes to see, wiiile the patient maintains his line of regard. For example, if only the left side of the papilla can be seen from the standpoint of the observer, the latter moves his head very slightly to the right. Of course the same result could be obtained by having the patient look a little more to the left, but the obsei'ver usually has his own movements under better control than those of tiie patient. //, in spite of (lU tliis, the observer Jias not siiceeeded in seeing tlie papiUii. or anfi portion of it. it is best for him to break off tite examination, to redireet the patient how to look (see under 1), and to try again. 8. The Investigation of the Macula is often difficult, even for the expert, so there should be no iiesitation to dilate tiie pupil wlien it cannot be seen clearly, and to examine the eye when in a condition of mydriasis. In doing this the rules should be observed that are given on page 11. The macula is so placed that in order to bring it into view eitiier the patient must look at the aperture in the center of the mirror, or the phvsician must move his own eye into the line of vision of the patient, while the latter remains looking in the same direction as during the presentation of the papilla. It is also possible, wliile tile eyes retain tlieir relative positions, for the physician to move the lens toward the patient's nose until the macula appears in its temporal margin. 8 9. For the Examination of the Periphery, which must ikvui- be omitted, tlie piitiout is told to look up. down, to the riight is thrown into the eye, and then the normal portions a))pcar to be bright while the detached parts are dark, or perhaps the detached bulla can be distinctly seen, especially if the observer draws rather near to the eye. We indicate the Place and Size of a Lesion in the Fundus by reference to the papilla and its diameter, which i> 1..") nnn. b'or example, we say that the size of a lesion is ^ •• a papillarv diameter, i.e., that its diam- eter is 0.75 nun, or that it lies 2 papillary diameters from the temporal margin of the disc of the optic nerve, i.e., 3 mm distant. THE DILATATION OF THE PUPIL FOR THE PURPOSE OF AN OPHTHALMOSCOPIC EXAMINATION is, under certain precautions, an absolutely harmless procedure, and it is to be recommended whenever the examination is rendered difficult by a small pupil. It is better to make an exact diagnosis with a dilated pupil than to make an incorrect or incomplete one because the pupil is too small. It is no confession of incompetence or ignorance. It is often almost essential for 11 the use of the direct method, or tlie examiiiiition of the macula. The only thin^ necessary is that certain precautions he ohservcd, and these are: 1- Never use atropine to dihite the ])uj)ils for this purpose, because it renders paretic not only the sphincter pupiUa', but also the acconnnodation for about 8 davs, so that the patient is unable to read or write for a week. What that means is readily appreciated by a pliysician who has once instilled atropine into his own eyes by way of experiment. 2. Care must be exercised in the case of old people, and if there is any suspicion of glaucoma. In the latter case it is best not to use any mydriatic at all ; it is often superfluous, as patients with glaucoma usually have pupils that are somewhat dilated and react badly to light. Not more than one drop of the mydriatic sliould he placed in the ej'e of an old person. The most suitable mydriatics are: It Homatropin. hych'obroni. . . . 0.1 1{ Cocain. hydrochlor 0.3 Aqu;e destil ad 10.0 Aqua- destil ad 10.0 !M. Sig. One or two drops to M. Sig. One drop to dilate the dilate the pupil. pupil. XoTK. — Not more tjian a single drop of cocaine should be used, because an exfoliation of the epithelium of the cornea may readih' be induced by the application of many drops ; and. while this is fairly harmless, it interferes with the view into the e3-e. Two, or even three, drops of homatropine may readily be used, except in cases of glaucoma and in old people. The method of instilling the drops is to draw down the lower lid with the forefinger of the left hand and to allow one drop of the solution to fall gently upon the inner surface of the lid from a dropper held in the right hand. It is of no use to instill a large number of drops, as they inmiediately escape. The patient is sent back into the waiting room and half an hour later we see if the pupil is dilated. Usually it is ; if it is not, another drop is instilled and the eye is seen again 15 minutes later. Tlie mydriasis begins after about 10 minutes and reaches its acme on the average in half an hour. Four or five hours later the pupil has usvially regained its normal size. The accom- panying disturbance of the accommodation is therefore comparatively slight, especially when cocaine is used. The Normal Papilla and the Normal Fundus Anatomical Review A brief review of the anatomy is essential in order to understand the ophthalmoscopic picture of the papilla of the optic nerve. This nerve enters the eyeball througli the lamina cribrosa of the sclera, to the inner side of and a little below the posterior end of the optic axis, and there forms the papilla. The optic nerve is to be considered as a portion of the brain that has been projected forward, and, like the latter, it is enveloped in 3 sheaths, the dural, arachnoidal, and pial membranes, the interspaces of which correspond to those of the brain and are furtlicrmore connected directly with the lateral ventricles. This fact explains how it is that an increase of pressure in the brain is transmitted into the optic nerve to produce a choked disc. The two outer sheaths pass over into the two outer layers of the sclera, while the inner one enters its innermost lamella, which forms the lamina cribrosa, and is connected with the cjiorioid. A number of vessels, which surround the optic nerve and are fed by the posterior short ciliary arteries, may be seen on transverse section in the neighborhood of the place where this change occurs. These vessels form Zinn's, or the sclerotic, vascular plexus. As this plexus gives off branches to the optic nerve a connection is formed between the vas- cular systems of the retina and the chorioid, but this union is of no practical importance. Two segments, the anterior and the posterior, need to be differentiated in the intraorbital portion of the optic nerve, because of the vascular supply. The anterior segment is supplied by the central artery and vein of the retina, which enter it in the lower medial quadrant, 10 or 12 mm from tiie eyeball, and then run axially in the nerve. The artery comes from the trunk, or a branch, of the ophthalmic artery, which in turn is a branch of the internal carotid. The vein empties into the cavernous sinus, or into tlic superior facial vein, and has numerous anastomoses with other veins in the orbit. The posterior segment receives its blood supply from a long, recurrent branch of the central artery of the retina and other branches of the ophthal- mic artery, and discharges its blood into the cavernous sinus. The optic nerve is circular on section ni its orbital portion and is about 4 mm thick. It is composed of nerve fibers and connective tissue. The nerve fibers form bundles that run parallel to one another, and are interlaced together by an interchange of fibers, the number of wliicli lias been estimated 15 16 at half a million. The nerve fibers have a medullary sheath, but no sheatli of Srincinni. ami a supporting- siibst.uicc composed of neuro^-jia tissue lies between tiiem. Tlie pial siuatli, uliieli is closely adherent to the surface of tlie lU'rve, sends numei'ous t i-aiiecul.-i' and srpla into it, wliiTe tliev .join to form a ni'twork, and to invelopi' the bundles of nerve fibcis. \\'itliin these are to be found the lymphatic and blood vessels. " ^gyi^^.j^r j^ry^^ 4. i ^- : ' f f Fit;. D. — ilicr(ise(i|iie Seelicni lhroiii;li a Xornial Ojitie Nerv'e. The lumina of vessels which form part of Zinn's vascular ]]le.xus can l)e seen at the place where the dural sheath bends over to join the sclera. The papilla is a flat surface in the drawing-, with no marked excavation. The caliber of the fibers of the 0[)tic nerve varies; the average is about 2 \f: The smallest are those of the papillomacular bundle, which supply the macula and form the medium oi tlie finest vision. This bundle is of a longi- tudinally oval form, situated in the center of the nerve at the optic foramen, from which j)oint it gradually approaches its temporal side, until at tiie place of entrance of the central vessels it lies wholly in its temporal margin and occupies the lower, outer sector of the disk in the form of a wedge with its apex inward. At the level of the inner surface of the sclera are numerous fibers of ccm- nective tissue cutting transversely through the nerve, whicli, together wltli other fibers of connective tissue from the sclera and chorioid, form the lamina cribrosa, through tlie numerous meshes of which passes the optic nerve, which at this point is 1.6 mm thick. The diminution of its diameter is due to its loss of the medullary sheaths that are retained as far as the posterior third of the sclera, and are lost just before the nerve reaches the lamina cribrosa. This loss not only diminishes the calibi-r, but also causes a change in its color; while the medullated fibers appear white, the nonmedullated look rather grayish. The fibers of the optic nerve bend outward in the papilla and arc dis- tributed in the layer of nerve fibers of the retina (see page 112). 17 A. THE OPHTHALMOSCOPIC PICTURE OF THE NORMAL PAPILLA The followinn; points luive to Ik- noted, one after another, in a systematic examination : 1. Form and size. 2. Color. 3. Margins. 4. Conditions of level, excavation or protrusion. 5. Vessels. 1. The Form of the normal papilla is usually round, or slio-htly oval vertically. Ia'ss often it appears to be horizontally, or obliquely oval, a peculiarity which does not usually correspond to an actual anatomical con- dition, but is produced by an astigmatism of the cornea. The variations in size are also only apparent as a rule; in hypermetropia the papilla seems to be larger, in myopia smaller, when examined by the indirect method, the reverse when seen by the direct. At the same time true differences in size are met with; sometimes the papilla is unusually small in the "little" hypermetropic eyes (see under Pseudoneuritis). Attention may be called here to a mistake often made by beginners, who sometimes include a circular staphyloma, in congenital myopia, with the nerve and are led to think that the papilla is enlarged. The color of the papilla is a delicate red which might aptly be compared to that of a peach blossom. The temporal side (upright image) is usually a little brighter than the nasal. In a large number of cases a specially bright spot is to be seen in, or a little to one side of, the center, which corre- sponds to the excavation about to be described. 2. The Color results from the combination of that of the lamina cribrosa and its meshes with that of the almost transparent fibers of the optic nerve. The former is almost white, except for the apertures, which have a gray appear- ance, while the optic nerve fibers, which are slightly gray, seem reddish from the presence in them of numerous capillaries. The observer sees through the almost transparent fibers to the lamina. At the places where the fibers are particularly' well developed and densely packed, for example at the nasal margin in the upright image, the paj)illa appears redder tlian where they are less in number, as at the temporal margin, over which pass the few and delicate fibers that supply the macula (see Papillomacular bundle). The brighter color of the temporal side is not, therefore, an indication of atrophy; this is indicated by a true white color. On the contrary, those places in which the optic nerve fibers are almost wholly wanting, as at the bottom of an excavation, must normally be white, the color of the lamina cribrosa. The color of the p;i})illa is also influenced by its environment. If this 18 is very dark, as in brunettes, the optic nerve will seem to he particularly bright from contrast, and, on the other hand, it looks redder when the fundus is particularly pale. The nature of the light, whether gas or electric, likewise exerts a certain influence, as the papilla appears to be paler or redder in proportion to the number of red rays it contains. It is also affected by age, as in youth the red prevails strongly, while a yellowish tone is apt to be acquired in old age. According to Elschnig, the size of the papilla, which is not always constant, has an influence on its color. As it must be supposed that there cannot be any excessive difference in the number of nerve fibers that reach the normal eye, small papillie are generally redder than large ones, because of the relatively denser layer of bundles of nerve fibers with the capillaries between them. 3. The Margins of the normal papilla are sharply defined. Special marginal rings are frequently present, one \jhite, the so-called connect ivi' tissue ring, or scleral ring, and one black, the so-called pigment ring, which is sometimes termed erroneously the chorioidal ring. The white ring may be due to two different anatomical conditions: it may be either a true connective tissue ring, separating the chorioid from the sheath of the optic nerve, or the sclera itself covered with rudimentary chorioiil and marginal tissue (see Fig. 1). The black ring is produced when the pigment layer of the retina in the neighborhood of the optic nerve is particularly thick and this thickening stands out prominently. If this ring lies close to the papilla a connective tissue ring cannot be seen, but otherwise there may be seen first a connective tissue ring and then a ring of pigment. It is only in exceptional cases that these circles are complete; segments only are visible, as a rule, and these are usually on the temporal side; frequently there is an accumulation of pigment instead of a black line, and sometimes one or both of the rings are entirely absent. Sometimes the chorioid, retina and sclera are pushed over the nasal mar- gin of the papilla, so that this appears thick and indistinct (see Fig. I iti the text and Fig. 5). This happens more often in myopic th;in in emme- tropic eyes. The margin of the papilla, that is, the portion of the optic nerve that is covered, shines quite weakly through the tissue as a yellow crescent, the supertraction crescent (see Fig. I in the text). The margin is more distinct on the temporal side than on the others for the reasons already mentioned. Age again plays a certain part, for the zone of pigment is usually devel- oped considerably more in infants than in adults. 4. Excavation of the Papilla. The name papilla dates back to the time when it was thought to be an elevation at the entrance of the optic nerve. This was an erroneous anatomical 19 idea; tlio p) in the intervascular spaces of the ehorioid. We distinguish, according to the quantity and distribution of the pig- ment in these two membranes, Three Types of the Normal Fundus. 1. The Uniform, Sfippki] Fundus (Fig. 1). The uniform aj)pearance of this type of fundus is brought about by the fact tiiat the layer of pigment epithelium contains so nuich and such dense pigment that the ehorioid beneath it is completely hidden from the eye of the observer. The tone of color is red, brown red, or black brown, according to tho quantity of pigment. 25 2. The Tessclated Fundus (Fig. 2). In this type the layer of pigiiicnt epithelium contains less coloring mat- ter; consequently' it is possible to see througli the almost transparent retina and to perceive the markings of the chorioid. TJie reddish chorioidal ves- sels are seen to form numerous anastomoses, and the pigment of the chorioid is massed in the interv^ascular spaces between them. The vessels appear as bright bands on a dark background. 3. The Albinotic Fundus (Fig. 3). In this t>'pe the layer of pigment epithelium contains little or no pigment, so the markings of the chorioid are again visible. But this membrane also has no pigment, and consequently the sclera is seen to shine through the retina and cliorioid. forming a yellowish white background, upon which the chorioidal vessels appear as dark bands. They can be distinguished from the retinal vessels by the absence of the light reflex, their abundant anas- tomoses, and their deeper position. Cases are often met witli which do not belong exclusivelv to any one type, but present the characteristics of two or more. The laver of pigment epithe- lium may be thick enough to hide the markings of the chorioid in some places, while in others it is thinner and allows the chorioidal vessels to appear on a dark (Type II), or a bright background (Type III). The pigmentation is usually densest about the papilla and in the region of the macula, so that even in an albinotic fundus the chorioidal vessels are not usually visible in the macula, although they can be seen in the less pig- mented places in the periphery. The abundance of pigment in the fundus is usually in keeping with that in the hair and skin of the individual, so that we speak of a blonde, and of a brunette fundus. The retinal vessels can easily be distinguished from the chorioidal. even in the albinotic eye, by noting the following characteristics : Retinal Vessels Chorioidal Vessels appear to be round, appear to be flat, have light streaks, have no liglit streaks, divide dichotomously, divide irregidarly, form no anastomoses, form many anastomoses, converge toward the papilla, have no uniform direction, or con- verge towai-d tlie periphery (vor- tex veins), are superficial. are deep. The Course of the Retinal Vessels varies according to the refraction of the eye. In myopia they are markedly drawn out, while in hypermetropia a marked tortuosity, especially of the veins, can often be seen. This tortu- osity is due to the growth of the eyeball being too little as compared with !2() the design of thu vessels. The normal conditions of circulation (for pressure pulse see page 107) juid tlic absence of any moriiid symptoms diflferentiate this from other forms of tortuosity, which are caused by morbid conditions of the vessels and intlannnations. The Retinal Reflexes form a very marked j)henomenon, especially in young persons, as they appear chiefly along the vessels and in the region of the macula (see Fig. 2). They appear in the forms of bandlike, or island- like spots, which can be recognized easily to be reflexes by the fact that tiiey change their forms and positions with movements of the head and mirror. They are particularly distinct when the vision is focussed on the deepest part of the vitreous, as when a -f"l) or a +- ghiss is used in looking at the fundus of an emmetropic eye; they are less distinct when the pupil is dilated than when it is contracted. The explanation of these reflexes is that, in con- sequence of the elevation of the surface of the retina by the vessels, concave grooves are formed which act like concave mirrors. A bright curved line can be seen in many cases on the nasal side of the papilla, running parallel to its margin at the distance of about one papillary diauRter. This is known as Weiss' reflex ring. It was thought by its discoverer to indicate a detach- ment of the vitreous, and to be pathognomonic of myopia, but this theory cannot be correct, as the line is met with in ennneti'opia and hypermetropia. It must not be confounded with the Weiss-Otto shadow ring, which is met with in high myopia and indicates the margin of a sclerectasia, the so-called staphyloma verum (see Fig. 73)- The Chorioidal Vessels have been described already, so it will suffice to say that they gather the blood into large veins, the vortex veins, which, to the number of four or more, usually lie in the periphery. In exceptional cases, oftenest in myopia, they lie at the posterior pole, as shown in Fig. 3- Macula. The macula deserves a special description. This portion of the fundus oculi has been termed the macula lutea because it contains a yel- low coloring matter; yet the area that contains this yellow coloring matter is considerably larger than the place that is designated ophthalmoscopically by this name. It mav' be recognized from the behavior of the blood vessels, which surround and direct their points at it without reaching it. The area thus surrounded by, but lacking in blood vessels, lies about ll/o papillary diameters from and a little above the papilla. It has the form of an oval, 5 papillary diameters (P. D.) broad, and 21/> P. D. high. Its center ap- pears rather dark. This, the macula lutea in the narrow sense, is surrounded in young people by a brilliant reflex ring 21/; P. D. broad and 1 P. D. high. This ring surrounds the part of the macula lutea which contains no nerve fibers. In the center of this ring the so-called reflex of the fovea can usually be seen in children, caused by the reflection of the light from the sides of the foveal funnel, and so it appears sometimes roiird, sometimes crescentic, some- times wedgeshaped, according to the way in which the lifht is thrown and the mirror held. PLATE I Fig. 1. Normal Fundus of the Uniform, Stippled Type Fig. 2. Normal Fundus of the Tesselated Type, with Numerous Reflexes from the Retina Fig. 1. Normal Fundus of the Uniform, Stippled Type (Sec page 2-i) If vrc study the papilla in tlie way repeatedly mentioned in the text, re- garding in turn its form, its margins, its diirerenccs of level, and its vessels, we sec the folliiwiiig details: The papilla is vertically oval, has sharply de- fined margins, very clearly marked connective tissue and ])igment rings, and a shallow excavation in its center. It is normal in color, the temporal por- tion distinctly brighter than the nasal. The j)igment epithelium is so dense that no details of the chorioid heneath it can he {)erceived. The pigment is jiarticularly concentrated about the pa])illa and in the region of the macula. The dark, larger vessels, without distinct light streaks, are the veins; the brighter, narrower ones, with distinct light streaks, are the arteries. Al- though their subdivision is not quite regular, yet the division above and below of both the arteries and the veins into 2 principal branches can be seen. A small branch of the artery and of the vein approaches the macula. Fig. 2. Normal Fundus of the Tesselated Type, with Numerous Reflexes from the Retina In contrast to Fig. 1 the markings of the chorioid can be seen over the greater part of this fundus. This is because the pigment layer of the retina is very thin and allows the tissue beneath it to show through. The dark, islandlikc places are formed by the pigment of the chorioid that lies between its vessels ( intervascular spaces, see page 25). As the vessels of the chorioid are brighter than the pigment lying in their vicinity, we say that the tes- selated fundus is characterized b^' bright chorioidal vessels on a dark back- ground. The papilla is vertical^ oval, and has a distinct connective tissue ring, but no pigment ring. Its temporal portion is brighter than its nasal. The pigment of both the retina and the chorioid is lacking in its vicinity, so there is a bright zone about the papilla. The macula and fovea can be seen quite distinctly because the reflections at their margins and along the courses of the vessels are verj"^ great. The bright spots in the vicinity of the macula can be recognized to be reflections from the fact that they change whenever the mirror is moved. This picture shows that there is little pig- ment in the retina, but plenty in the chorioid. 28 Tab. Fig. 1. Fig. 2. PLATE II Fig. 3. Albinotic Fundus Fig. 3. Albinotic Fundus This picture shows a complete absence of pigment in both the retina and chorioid. The vessels of the latter can be very plainly seen to unite into larger trunks, the vortex veins. The arteries and veins cannot be distin- guished from each other. The confluence of the vessels of the chorioid in the neighborhood of the papilla is rather unusual, in most cases this takes place in the periphery, in the region of the equator. The complete absence of pigment in the region of the macula is likewise not common ; more often there is a distinct accumulation of pigment at this place, even when the albinism is perfect otherwise. The papilla is bright red, but only in consequence of the effect of contrast with its pale surroundings, its margins are sharply de- fined, the excavation is vei-y shallow, the retinal vessels are normal. For the differentiation between the vessels of the retina and those of the chorioid, see page 2.5. A partially albinotic fundus is shown in Fig. 8- 30 Tab. a. Fig. 3. Conus and Staphyloma Differential Diagnosis of the White Rings and Crescents to be Found in the Immediate Vicinity of the Optic Nerve Conus and Staphyloma Differential Diagnosis of the White Rings and Crescents to be Found in the Immediate Vicinity of the Optic Nerve The head of thi? optic norvc affords a number of anoniiilics of tliis nature which are apt to be thought parts of the papilla by those who arc not expert, and to be grouped by them under the term "large papilla," but, with some attention and knowledge to the factors that enter into the problem, it is not difficult to differentiate the individual conditions, and to draw from them important conclusions with regard to the diagnosis. The principal conditions to be taken into account are : 1. Conus temporalis. 2. Staphyloma posticum. 3. Peripapillary atrophy of the chorioid. 4. Conus inferior. 5. Halo. 6. Medullated nerve fibers. I exclude here all inflammatory affections, such as optic neuritis, great fullness of the vessels, a?dema, and hemorrhage, and emphasi/.e the point that this classification serves a purely practical purpose. Conditions are grouped together which have nothing to do with one another, either anatomically or etiologically, but have only some features in common; they have a certain resemblance to one another in form, color, and ]>osition, which may lead those who are inexperienced into error, and, on the other iiand, one of them may appear alone in an otherwise normal fundus.^ The features common to all these contlitions are: 1, the color, which is usually a yellowish, or bluish white; 2, the position, in the innnediate neighborhood of the ]>apilla ; 3, the form, of which the crescent and the circle are the principal types ; 4, the absence of signs of inflammation. In order to differentiate the individual conditions we will group tlirin first with regard to their positions as respects the papilla, as they are seen in ' A number of other conditions mi.t;ht be inchnloJ, sueh as cololioniii of the sheath of the optic nerve, certain forms of ooloboma of the chorioid, abnormal developnient of the glia tissue and of connective tissue, but they have been omitted because of their rarity. 33 34 the upright imagu, rt'inombering that everything is reversed in the inverted image. («) On its temporal side lie, or may lie tlie conns temporalis, the st;ij)li\l()ma posticnni, the peripapillary atroi)iiv. (b) Belme it the conus inferior, niedullatcd ner\e fibers. (c) Surroitiiiliiig it the halo, the staphyloma posticum annulare, the peripapillary atrophy. (f/) Above it medullatcd nerve fibers, or the peripapiUary atrophy. Such an arrangement as this may seem at first glance to be rather risky, because other conditions may combine with those that have been mentioned and overthrow the artificial fabric ; thus the staphyloma posticum may appear in company with hemorrhages, or with diseases of the macula, or, in excep- tional cases, retinitis albuminurica may present an appearance which seems at first sight similar to that of these conditions. But I consider this differ- ential diagnosis to be of sufficient importance to introduce it at this place in spite of these objections. 1. The Conus (Figs. 4 and 5) is a uniformly yellowish white crescent that ordinarily lies to the temporal side of the nerve, to the nasal side in the inverted image, which rarely attains at its widest part the breadth of half the diameter of the papilla. Toward the retina it usually presents a more or less broad edge of pigment. Tiiis is the connnon form of conus, which, when typical, can be distinguished from the staphyloma by the fact that it exhibits no visible vessels of the chorioid. The conus inferior will be described a little later. Certain deviations from this typical form are met with. The conus may, though rarely, lie on the opposite side of the nerve, but then it extends, at least partially, toward the temporal side. In rare cases it may surround the papilla, but then the temporal portion is the broadest. The color may vary also. The crescent may be white only at the mar- gin of the optic nerve and may have a reddish yellow, or a reddish brown tone toward the retina, or the entire crescent may be of such a color. A change in the medial margin of the sheath of the optic nerve, the so- called supertraction, may be found comparatively often at the same time with the conus temporalis. This is due to the fact that the retina, chorioid, and it may be even the sclera, cover the optic nerve at this place, so that it can be seen only indistinctly through these membranes. 35 The conus may be the result of vai-ious anatomical conriitions, which dif- fer again as thev are congenital or accjuired. A. The congenital conus is due to tlie fact that the outer layers of the retina and of the pigment epithelium, as well as the chorioid, are rudi- mentary, or not formed at all, over the area that is white, so that the sclera shows through. This form differs only quantitatively from the scleral ring. It can readily be understood that this form of conus occurs in other than myopic eyes, and that it is not necessarily strongly marked on the temporal side. B. Acquired conus. This is the result of the stretching that takes place in the posterior part of the globe in myopia. It may be caused in va- rious ways, and it is necessary to recall the normal configuration of the Pig. I. — Head of the Optic Nerve in Myopia, after Fiichx. The upper drawing- gives the ophthalmoseopie appearance presented by the condition delineated in the lower. When compared with Fig. D the oblique course of the optic nerve is striking; it does not pass through the sclera thus / \. but thus \ \. Consequently the sclera is seen through the retiua and chorioid on the temporal side, on the left side in the drawing, which gives the picture of a white crescent, or conus. On the opposite side the optic nerve is covered by the retina and chorioid, partly also by the sclera, so that this portion of it is seen only through these membranes and appears as an indistinct, ill-defined crescent, which is called the supertraction crescent. sclerotic canal, the aperture in the sclera through which the optic nerve passes, in order to understand it. Normally this canal forms a funnel with its smaller opening forward, thus / ■ ■ ■ •\, hut when a conus is present the temporal side has been ground off so as to form an oblique canal vn\\\ parallel 36 walls, tlius \. • • •\. As the tissue covering the optic nerve is transparent the wall of the canal at this place can be seen, and forms the ophtiiahnoscopic picture of a conus, also called a dint ruction cnscint. Another form of conus, calkd the retraction crescent,^ is produc(>d in the following way : The retina antl the chorioid do not yield if|ualiy in the stretching at the posterior pole, the elastic lamina of the chorioid, in particular, not giving way in like manner as the retina. As it does not simply stop at the margin of the optic nerve, but is intimately united with its interstitial tissue, a fold of the optic nerve fil)ers is apt to be torn between the retina and the stroma of the chorioid. The latter then perishes, so the white color at this place is caused by the color of the sclera plus that of the glia fibers over it. With regard to the origin of the so-called supertraction crescent, see. Fig. I in the text and the accompanying explanation. Aside from the rare cases of congenital conus that may be met with in hypermetropia and enmietropia, we must consider the Conus as a Sign of Myopia. We may go even a step farther. There are two forms of myopia, the acquired and the congenital. 'i"he former develops during school life, espe- cially in children in the higher grades, and near work is an etiologic factor in its production. This is the benign form of myopia, which rarely exceeds 6 or 7 D, and is complicated only in exceptional cases by diseases of the macula, or detachment of the retina. The pathological condition in this form is a uniform stretching of the segment of the eyeball that lies behind the equator. As this process of stretching is very slow, uniform, and of comparatively slight degree, and as it usually stojjs when the body ceases to grow, its effect is exhausted in the formation of the conus which has been mentioned. It is otherwise with congenital - myopia. This ordinarily exhibits patho- logically a circumscribed stretching, confined to the region of the posterior pole, but one which is much more marked than that in the form just de- scribed. It is associated with a greater or loss degree of outward bulging of the sclera, and gives ophthalmoscopically the impression of a staphyloma posticiun. This is the malignant form, which is apt to be complicated by ^ The nomenclature of these crescents is not uniform. Many writers call the one here named the retraction crescent, the distraction crescent, and vice versa. Others make no distinction between conus and staphyloma, understanding by the latter only a true bulging outward of the posterior pole of the eyeball, and by conus the ophthal- moscopic appearance caused by that condition, indifferent to whether it presents obliterated vessels or not. - The expression "myopia to which the predisposition is congenital" is, perhaps, a better term than "congenital myojiia." for one that develops siwntaneously without any externa] provocation, like near work, must be taken into account. 37 changes in the macula and (litacliiiient of the retina, and to attain a high degree. Between tliese two extremes ari' t i-ansitioiial forms, !)ut in general it may be accepted as a fact tliat, the conus is an indication of acquired myopia, or "school my- opia," and the staphyloma is an indication of congenital myopia. 2. The Staphyloma (l""igs. 6, 70-73) appears ophthahnoscopically as a white crescent, usually larger than a conus, which is situated in most cases on the temporal side of the papilla. Less often it surrounds the nerve, but even then its broadest part is on the temporal side of the latter. In contrast to the condition presented by the conus, sclerosed chorioidal vessels arc found either in the crescent, or in its immediate vicinity. The name staplivloma deserves explanation. Properly speaking, the above-mentioned outward bulging of the posterior pole of the eye is to he understood when we speak of a staplivloma, but the term is also applied to the crescent, which is the ophthalmoscojiically visible evidence of its presence. Aside from an outward bulging and a thinning of the sclera, the same pathological conditions are to be found as in acquired conus, except that atrophy of the chorioid, particularly of its vessels, forms so prominent an addition to the symptoms that wc may say, cum grano salis: The presence of sclerotic r-es.icls of the chorioid, especiaU// ii) the vicinity of the crescent, is indicative of staphi/lonui, their absence of conus. Still, the breadth of the crescent and the presence of other changes nmst be taken into account in making the diagnosis. Fig. 6 shows a staphyloma posticum in tlie early stage of its develoj)- mcnt. The sharply defined crescent can be seen to contain chorioidal vessels, some of which are totally obliterated, while some contain blood, with the black pigment of the intervascular spaces distinctly visible between them. On the farther side of the margin of the staphyloma are to be seen chorioidal ves- sels that have undergone similar alterations, but these are still covered by the veil of pigment, which is absent over the area occupied by the crescent. This staphyloma may hasten through all the stages of atrophy of tlie chorioid until it is total, as shown in Fig. 54. Sometimes the time of the completitni of the atrophy varies in different parts of the staphyloma, so that breaks appear through which the pigment of the chorioid can still be perceived within it in some places, while in others it cannot (Fig. 70). In many cases, how- ever, these breaks are not caused by the unequal advance of the atrophy, but by shadows that are produced by irregular outward bulgings at the posterior pole. Such a shadow may also appear around the posterior pole, but it is usually to be seen only on its nasal side, and is frequently double, or nndti- ple, giving rise to a terraced appearance (Fig. 73). A fine, brilliant, re- flex curved line is frequently to be seen on the nasal side of the ])apilla. which was once thought to indicate a collection of fluid between the retina and the chorioid, and a commencing detachment of the vitreous, but this interpreta- 38 Fig. J. Schematic sketch to show how the papilhi is caused to appear out of drawinsr in hifrh myopia. The ectasia affects exactly the posterior pole of the eye; the papilla is situated in its nasal ■wall and is consequently seen in half profile with its horizontal axis fore- shortened. The white crescent, the staphyloma, is directed toward the center of the ectasia. Fig. K. In this case the ectasia does not lie exactly at the posterior pole but rather below it ; hence the papilla is not situated exactly in its nasal wall, but in its upper and nasal, and the foreshortening is consequently of its oblique axis. The white crescent, the staphyloma, is directed toward the center of the ectasia. Fig. L. In this case the ectasia lies to the nasal side of the posterior pole so that the papilla occupies the bottom of its cavity. Consequently we look directly at it, and it ap- pears to be of its natural, round form. The staphyloma is circular. £9 tion is not correct, as sucli a lino sometimes appears in other conditions of the refraction (see page 26). The papilla itself may appear eitlii'r normal, or reil(ii>h and indistinct when a staphyloma is present. The redness and indistinctness are due partly to the pulling, partly to the effect of contrast with its bright surroundings. The retinal vessels are very slender and drawn out (see page 105). The form of the papilla is quite interesting. As a rule it is not round, but oval, with its short diameter vertical to the broadest part of the staphyloma ; i.e., if the latter is broadest in the horizontal meridian the papilla appears to be vertically oval ; if the broadest part inclines somewhat downward from this meridian, the principal axis of the papilla is oblique. The explanation of this is that in the majority of cases we do not look directly at the papilla, in consequence of the ectasia of the posterior pole, but at it in half profile, as has been shown by Dimmer. The papilla lies to the nasal side of the pos- terior pole of the eye; the more this is stretched the more the papilla moves toward the inner side of the cavity formed by the ectasia ; if the ectasia is strictly on the temporal side of the papilla, the latter lies strictly on the nasal side of the former, and the foreshortening then affects only the hori- zontal axis (Fig. J), but if the ectasia is downward and outward, the papilla clings to the upper inner wall of its cavity, and the foreshortening takes place in an oblique axis (Fig. K). As the atrophy of the chorioid occurs chiefly in the places where the stretching is greatest, this relation between the form of the staphyloma and that of the papilla is readily understood. If the ectasia is situated on the nasal side of the posterior pole the papilla occupies the floor of tiie hollow and consequently we look directly at it, and as the hollow made by the ectasia is on all sides of the papilla, the staphyloma is circular (see Fig. L). 3. Conus inferior (Fig. 8)- This is a special form of conus which is to be regarded as a rudimentary coloboma of the chorioid. Like the latter, it lies l)elow the nerve, and is usually associated with a change in the form of the papilla, which is, in most cases, obliquely or transversely oval, and seems to be smaller than normal. The dividing line between the conus inferior and the papilla frequently is not as distinct as it is in Fig. 8. Anomalies in the nature of the excavation and in the subdivision of the vessels are often present. In almost all cases, though to a greater degree in some than in others, the color of the fundus is uniform in its upper part and almost alhinotic m its lower. Astigmatism and amblyopia are usually associated with this form of conus. The conus inferior differs plainly from the staphyloma posticum and the conus myopicus not only in its position, but also in the absence of scleroses in the vessels of the chorioid and in the form of the papilla. 4. Peripapillary Atrophy of the Chorioid (Fig. 65). Peri- and parapapillary atrophy of the chorioid, the result of arterio- 40 sclerosis, is quite siiiiilur in appciirancc to staphylomn. posticum. It is char- acterized l)y white cords formed by tiie sck'rotic vessels of the chorioid, while the sharply nut lined form of a crescent is generally absent. Its margins arc indistinct, and it sends out narrow projections, liihy (atrophy after choked disk) white indistinct normal ; after choked disk rather elevated papilla veins engorged, tortuous, and sheathed variable Ketinitic atrophy pale yellow, or dirty reddish to gray yellow obscured normal threadlike very great concentric contraction Atrophy of the ^^^^:'f,. papiUomacular .V, ."r bundle from toxic '"^|:' ;;;^'*'' causes and mul- , ..'^ ',?, tiple sclerosis ^^^^^ distinct normal normal central scotoma for green and red, later for all colors already exists it may .seem to become enlarf^ed by the rounding off of its margins, especially when tlie difference of color between the papilla and the ffoor of the excavation disappears as the atrophy progresses; but even in such a case it is better to speak of an atrophy with a large physiological excavation, than of an atrophic excavation. We have to distinguish between total and partial atrophies. This can apply naturally only to the completed condition characteristic of the clinical picture, for in commencing total atrophy the process will be most marked at the place where the nerve fibers ai-e weakest, where a brighter tone of color prevails, i.e., on the temporal side of the papilla, so that in this stage the total may present the appearance of the partial atrophy. On the other hand, a partial atrophy that has existed for years may become total. It follows from what has been said, and from xchat is yet to come, that we must nt)t be contented with the diagnosis "atrophi/," hut must trif to ascer- tain the specific diagnosis of simple, neuritic, and other forms, from the sijmp- 53 toms that are present. This uill not prove difficult to those zc-ho ore accus- tomed to consider the papilla always from the ^ points of view, to take into account its color, miiryins, level, and vessels. A. Total Atrophy 1. Simple Atrophy^ (Figs. 10 and 11). Simple atrophy presents the foHowing characteristics: Color: white to gray white. Margins : - normal. Level: normal. Vessels : normal. Hence, the color alone is changed. The retinal vessels may become smaller in the later stages, so as to resemble nutritional atrophy, but this does not belong to the typical picture. What etiological conclusions can be drawn from such a condition? Un- fortunately, very many. The atrophy may be of a true neurogenous origin, caused by cerebral disease, when it is primary, or it may be due to injuries or compressions, when it is secondary. We see the same picture in both cases. The true diagnosis will depend therefore on the findings in the general and neurological examination, unless we are able to find other points in the eye that are of diagnostic assistance. Primary atrophy is the same as that which has frequently been termed gray atrophy, but — we may almost say again unfortunately — the color has no signification in the differential diag- nosis. In the first place, the gray tone of color is met with comparatively seldom ; in the second, it has been seen many times in other forms ; in the third, it may disappear and give place to a white tone after it has once been observed, or the reverse may take place. As the other ophthalmoscopic details, the margins, level and vessels show no deviation from the normal in typical cases, we have to include under the caption of simple atrophy clinical pictures which are etiologically very different. This is why it is so important to notice all other ocular symptoms, and to investigate the general condition. Etiologically, tabes is the first disease to be thought of; then come general paralysis and syphilis. Syphilis of the optic nerve usually appears in the form of a neuritis, or of a neuritic atrophy, yet syphilitic diseases of parts that are situated more centrally, such as meningitis, gumma of the chiasm, and hydrocephalus, may cause a simple atrophy secondarily. Tabes surpasses everything else in importance. Tabetic atrophy begins, as a rule, very early in the disease and may be for years its only symptom. It rarely 1 A number of animals have perfectly white papillse. for example, the rhinoceros, the armadillo, the porcupine, the anteater, and the hedsrehog-. 2 When a eonus or a staphyloma is annexed to the atrophic papilla it may be differentiated from the latter by the fact that it presents a peculiar, ruther yellowish white, instead of the white of the papilla. 54 appears at the same time with the ataxia of tlie lower liiiihs. Out of the large number of patients tliat I Iiave seen who were hhiulcd by this disease, I can reeollect only a very few who had a high degree of ataxia. Althoiigii it is to be feared that a tabetic who closes his eyes will lose his balance and fall, because of his ataxia, these blind persons, in whom likewise the sense of sight for orientation is absent, go about quite well, antl present the same appearance as other blind persons. Tabetic atroj)hy almost always affects both eyes and leads to blindness, though with remissions. Tabes frequently causes an ocular triad; atrophi/ of the optic nerve, paresis of the ocular muscles, reflex imvtohflit// of the pupils. Differential diagnosis. When we find a reflex immobility of the pupil associated with a simple atrophy of the optic nerve, the case is one of tabes; when the immobility of the pupil is absolute, i.e., when the pupil does not react to either light or convergence, especially when the pupil is also dilated, general paralysis or syphilis is probably present. Meiosis occurs only in tabes. On the other hand, the reactions of the pupil may be preserved in syphilis, while this is almost never the case in tabes. A paresis of the abducens, or a paresis of a portion of the oculomotorius, is indicative of tabes, while a facial paresis, especially in connection with symptoms of hemi- plegia, points rather toward general paralysis. Sometimes syphilis appears quite like tabes in its accompanying symp- toms, and then the differential diagnosis may be very difficult, the more so as Wassermann\'i reaction is often positive in tabes. Atrophy of only one optic nerve, an accompanying hemianopsia, total internal ophthalmoplegia, bilateral paresis of the oculomotor nerve, or bilateral ptosis, generallv indi- cate that the disease is syphilitic rather than tabetic. The field of vision in tabes usually shows sectorlike, or concentric losses. A central scotoma with total atrophy is indicative of syphilis, with partial atrojihy of nniltiple sclerosis.^ None of the other causes are very frequent. Among them may be men- tioned as particularly important, interruption of the conductivity of the optic nerve (Fig. 10) by direct or indirect injuries, as in fracture of the base of the skull, compression in the optic canal, as in oxyccphalus, slowlv growing tumors at the base of the skull, hydrops of the third ventricle, and pressure of the arteriosclerotic carotid upon the intracranial portion of the nerve. Pathologically, simple atrophy of the fibers of the optic nerve takes place without material proliferation of connective tissue; both the vessels ^ In the rare cases of tabes with central scotoma there is a concentric contraction at the same time; this is not present in multiple sclerosis. Another dilTereuce be- tween tabes with central scotoma and multiple sclerosis is that in the former the papillae are pale at a time when the vision is still good, while in multiple sclerosis it is the vision that is lost first, it may be rather suddenly, and the papilla subsequently becomes pale. 55 and the capillaries are preserved. Hence the white or gray discoloration of the papilla cannot be caused in tiiis way. It is probably due to the changed optical conditions induced by tiie atrophy of the nerve fibers, whicli make it possible for the lamina cribrosa to reflect the liglit that falls upon it more sharply and in greater quantity than it can under normal conditions. 2. Nutritional Atrophy. The appearance of this may be extremely like that of the atrophy just described. Only the absolutely negative evidence of a neurological and internal examination, with the exception of an arteriosclerosis that is often moderate, together with the condition of the retinal vessels, proves the diagnosis. As is to be expected in arteriosclerosis, this form of atrophy is usually met with in old people. It is not rarely found in company with arteriosclerotic vessels in the chorioid, which often surround it like a staphyloma (see page 39). For this reason the margins of the papilla appear somewhat indis- tinct in many cases, but this is due only to the absence of contrast. Other- wise the margins in this form are sharply defined, the level is normal, tiie vessels alone are altered. In many of these cases the first things that can be seen by accurate observation are irregularities of caliber, thickenings of the walls, and obliterations of the smaller vessels, such as will be described later under "The Changes in the Vessels of the Retina," and are considered to be characteristic of arteriosclerosis of these vessels. The visual disturb- ances are comparatively trivial in these cases, and the atrophy caused by chronic disturbances of nutrition are differentiated by this fact from the Atrophy Due to Occlusion of the Arteries The picture of acute occlusion of an artery is shown in Figs. 44 and 45, and is described on page 150. After the acute symptoms have passed away a condition develops which is illustrated by Fig. 16. The arteries are threadlike, no longer visible in some places, the optic disk is white, with normal margins and level ; usually, though not always, small patches of degeneration are found in the macula, which are called coronuhe and are described on page 127. The vision is usually totall}- lost in these cases. 3. Glaucomatous Atrophy (Fig. 14). The color in this form of atrophy is a gray white rather than a pure white, as a rule; tlie margins of the papilla are sharply defined, but in many cases they seem to be obscured by a surrounding ring, tlie so-called halo. We should observe carefully where the papilla stops and the halo begins, the line of separation can usually be recognized plainly from the differ- ence in color between the two. The vessels are rarely quite normal, the veins are usually In'oad. sometimes varicose, while the arteries are engorged only at first, frequently pulsate, but later appear to be contracted. 56 This form is sli;ir])l_v (lillVrinl iaicil from all otliers by the behavior of the vessels at the mart^iii of thr jiapill.i. As can be phiiiily seen in Fig. 14, tlic course of the vi'ssels up to the marniii of tlie optic disk is perfectly ^ J .J Fin. M. — (ilaueomatiuis Exeuvation. The exeavation be.ains sharply at tlie margin of the papilhi. The optic nerve is laterall.v ponched out on its nasal side. When we look from in front upon a ves- sel that dips down at this place it will not be visible as it courses along this pouch, but will apparently come to an end at the margin of the papilla. The optic nei"ve itself is reduced by atroph.v. These pathological conditions correspond to what is seen ophthalmoscopically in Fig. 14. Fig. N. — Deep Physiological Excavation. In contrast to the preceding drawing the excavation does not begin at the margin of the papilla, but normal tissue lies between the margins of the disk and of the excavation. A vessel coursing over the margin of the excavation may bend in a manner similar to that followed by those in a glaucomatous excavation, but this bend does not take place at the margin of the papilla. The corresponding oishthal- moscopic picture is Fig. 15. 57 normal, but tlifre thuy Ix'nd suddenlj- and sucni to disappear in tlic cavity; it is only by a change of focus — in the direct method by the interposition of a concave glass — that they can be seen in the floor of the excavation. From the difference in focus and from the parallactic displacement (see page 9) between the vessels on the margin of the pajjilla and those on its floor, the difference of level between the excavated papilla and its surrnumi- ings can be determined. The floor of the ])apilla usually lies 1 mm behind the level of the retina. The fact that it is abrupt and extends to the margin distinguishes the glaucomatous from the physiological excavation. When- ever a vessel is seen to make a distinct hook over the margin of the papilla the diagnosis of glaucoma is justified. Usually the excavation is total. The markings of the lamina cribrosa are very plainly visible in fresh cases, but in older ones they are hidden by the proliferation of connective tissue. It may be said here that the color of the optic nerve need not be abnormal in the commencement of a glaucoma, but that the excavation and the behavior of the vessels suffice for the diagnosis. Moreover, under the influence of an antiglaucomatous treatment the excavation undergoes involution in many cases. In old glaucomatous eyes we find obliterations of the vessels throughout entire areas of the retina, as well as a new formation of large vessels at the margin of the papilla, or in the excavation; sometimes junctions between the retinal and chorioidal vessels, the so-called opticociliary vessels, are also to be seen (see page 10-i). 4. Ncuritic Atrophy (Figs. 12 and 13). Neuritic atrophy is clearly distinguishable from all of the other forms by the indistinctness of the margins of the papilla, and by the invisibility of the apertures in the lamina cribrosa. In the atrophy that follows neuritis, or choked disk, the papilla is at first white gray with striated or obscure margins, but this color changes pretty soon into a pure white. The margins remain indistinct and striated; no excavation and none of the details of the lamina cribrosa are to be seen. The surface of the papilla usually rises a little above the level of its sur- roundings, to a fairly high degree when the atrophy is due to choked disk. The vessels are always changed ; the veins are tortuous, engorged to a greater or less degree, while the arteries are smaller than normal. This difference is particularly marked in old choked disk (see Fig. 13). In the majority of cases the vessels are also accompanied by white stripes. Newly formed vessels, which are frequently twisted like corkscrews, or formed into loops, are not rarely seen on the papilla ; opticociliary vessels (see page 104) are also observed more often than usual. These phenomena become the more marked the longer the inflannnation has lasted. In cases that run a rapid course a neuritic may therefore some- times appear very like a simple atrophy, and inflammations that occur in 58 old age arc apt to have severer seciiula' tlian tliosc that affect younger persons. The differences between the atropines caused by inflammation and by choked disk equalize themselves in the course of time, especially in young people, so that it is sometimes impossible to make a differential diagnosis between these two forms. Tf the inflammation was not confined to the papilla, but involved its surroundings, discolorations and partial vascular changes of particularly high degree are iiccustomed to appear as sefpiehe. On tlu' other hand, there is in many cases an entrance of pigment into the atrophic retina, as shown in Fig. 12, which causes an uncertain grayness about the optic nerve. Pathologically, tlic indistinctness of the margins of the papilla, as well as the stripes that accompany the vessels, are to be ascribed to a jiroliferation of the glia tissue, though the stripes along the vessels may be caused in part by changes in the tissue of the walls of the latter. Etiologically, all of those factors have to be taken into account which can cause an optic neuritis. The so-called retrobulbar neuritis can never cause a neuritic atrophy. 5. The Atrophji of the Papilla 'ni lietinitis Pigmentosa (Fig. 51) is to be considered only as one symptom of a clinical picture, but, as it is usual for the glance of the observer to fall first on the pa])illa when he is making an ophthalmoscopic examination, its characteristics may be mentioned here. Retinitic atrophy has a certain resemblance to the neuritic form in that the margins of the papilla are indistinct : its color, however, is conmionlj- a yellowish gray, rather than a pure white. What is particularly marked is the great diminution of the size of the retinal vessels, which ordinarily .show no changes in their walls ; in this respect it may resemble nutritional ati-ophy, es])ecially when due to occlusion of the central artery, but it may be differentiatid from this by the condition of the margins, which usujillv are sharply defined in nutritional atrophy, indis- tinct in retinitic, and by the color, which is white in the former, yellowish in the latter. The condition of the retina, especially in the periphery (see page 174), is decisive as regards the diagnosis. B. Partial, or Temporal, Atrophy of the Optic Nerve The margins, level, and vessels are perfectly normal ; the only variation from the normal to be seen is the paleness of the temporal side of the papilla. As large physiological excavations situated in this portion may simulate a temporal paleness under certain circumstances, and. on the other hand, as the temporal portion of the disk is normally nuch brighter th.ui the nasal, it is evident that great care must be exercised in making the diagnosis. If the diagnosis cannot be made positively from the ophthalmoscopic 59 picture, the field of vision is to be investigated. If a central scotoma ' is found, with the outer portions of the field normal, which is at first only f(jr green and red, later for white also, a positive diagnosis of partial atrophy may be made. The determination of the etiology is of very great importance, as the temporal paleness may be caused by very different diseases. 1. Chr-onic iutoxicdtions. Preeminent among these is poisoning with alco- hol and tolnicco. It is still a question whether tobacco alone can produce such an eifect. Then follow the toxic effects of methyl alcohol, lead, bisul- phide of carbon, atoxyl, quinine, filix mas, and arsenic, as well as of auto- intoxications, particularly in diabetes. 2. Multiple sclerosis. The visual disturbance caused by this condition is present in about half of the cases of multiple sclerosis, and may precede b^' years all other signs. Nystagmus when the eyes are turned as far as possible to one side or the other is frequently present as an accompanying symptom, paresis of the ocular muscles are less common, and an immobility of the pupil is almost never seen (see page 54<). 3. The inflammatori/ diseases of the posterior ethmoidal cells and of the sphenoidal sinus may bring about a similar picture through an extension of the inrtammation to the optic nerve, or through the influence of toxines some time after its subsidence. It follows from the nature of the cause that the disease regularlv aff'ects both eyes in Case 1, while in Cases 2 and 3 only one eye may be affected. Pathologically this is to be considered as a secondary atropiiy of the papillomacular bundle of optic nerve fibers, which passes over the temporal margin of the papilla and supplies the macula ; hence the central scotoma. The disease actually begins in the ganglion cells of the retina. ^ The stereoscopic method of Haitz for the determination of a central scotoma is very simple and valuable (see page 79). PLATE VI Fig. 10. Simple White Atrophy of the Optic Nerve Fig. 11. Simple Gray Atrophy of the Optic Nerve Fig. 10. Simple White Atrophy of the Optic Nerve (Sec page 5:3) When wc study systematically the color, marn^ins, level and vessels of the jiapilla wc see that its color is white, except for some sHppling which indicates the apertures in the lamina cribrosa, that its margins are distinct, that its level is the same as that of the retina, and that its vessels are normal. Therefore everything about it is normal except its color, so that, by applying our schedule, we are led to the diagnosis of simple atrophy. Hence we have to think first of tabes, but in this case the result of the neurological exam- ination was negative. The history stated that a stick had penetrated the orbit of the patient at a time when he was stooping, and that the eye had been made blind innncdiately. The diagnosis therefore was atrophy after interru])ti()n of conductivity (see page 54). The fundus is of the tesselated type, the retina is more strongly pig- mented in the region of the macula, distinct reflex stri.e are visible along the vessels. Fig. 11. Simple Gray Atrophy of the Optic Nerve (See page 53) As in the preceding picture the color of the disk is the only deviation from normal ; the margins, vessels and level are normal. The dark spots in the fundus are caused by the pigment in the chorioid showing through the retina (tesselated fundus). This patient had tabes. In the later course of the disease the gray became brighter, and the vessels smaller. 62 Tab. 6. Fig. 10. Fi- 11. PLATE VII Fig. 12. Atrophy after Inflammation of the Optic Nerve, Neuritic Atrophy Fig. 13. Atrophy of the Optic Nerve after Choked Disk Fig. 12. Atrophy after Inflammation of the Optic Nerve, Neuritic Atrophy (See page 57) The papilla is white, its margins indistinct, the excavation and tiu' mark- ings of the lamina crihrosa are erased, the vessels are bordered hy white stripes. The indistinctness of the papilla is due to a proliferation of glia which does not cease exactly at its margin and fills the cavity of the excavation. The stripes along the vessels are caused partly by a proliferation of glia, partly hy changes in their walls (see page 58). Pigment has migrated into the retina, which has been rendered atrophic by the inflammation, and has produced the gray halo about the jiapilla. The cause of the optic neuritis in this case was syphilis, which had been acquired 3 years before. Fig. 13. Atrophy of the Optic Nerve after Choked Disk (See page 57) As in the preceding case, the margins of the papilla are indistinct; it can be seen from the ring surrounding the disk how far the swelling extends into the retina. The papilla is distinctly elevated, as is shown by the mounting of the vessels at its margin ; the vessels themselves show the disproportion in size between the arteries and veins characteristic of choked disk. The vision was much impaired in this case. The otiier eye of the patient, who died of gliosarcoma of the cerebellum soon after the completion of tho picture is shown in Fig. 25. 64 Tab. 7- Fig. 12. Fig. 13. PLATE VIII Fig. 14. Glaucomatous Excavation and Atrophy Fig. 15. Large Physiological Excavation Fig. 14. Glaucomatous Excavation and Atrophy (Seu payc 55) The color of the pjipilla is gray in the center, with a gray green shadow tone in tlie ninrgiiial i)ortions, especially on the nasal side, which varies some- what with tlir way in which the mirror is held, and is caused by the over- hanging of the in.iigins. Tlu' papilla is encircled by a sliarply defined scleral ring, to wiiich is added a yellowish gray ring wliich blends with its surround- ings in a less distinct margin (iialo glaucomatosus, see page 40). Its level is much deeper tlian that of the retina. The retinal vessels are not mate- rially altered, but they break off and disappear exactly at the margin of the disk, and from this we conclude that the excavation is abrupt and extends to the margin of the nerve. Comj)are with this the pathological drawing, Fig. M in the text. The rest of the fundus is uniform and sti])pled. The vision in this case had fallen to one sixth of the normal, and there was a considerable concentric contraction of the visual field, particularly marked on the nasal side. Fig. 15. Large Physiological Excavation (See page 50) In contrast with the preceding picture we see here a narrow zone of normal tissue between the margins of the papilla and of the excavation. The color, margins and vessels of the papilla are normal. The vessels of the retina do not stoj) at the margin of the excavation, but can be plainly traced, although their direction is changed. We conclude from this fact that the sides of the excavation are not precipitous, as in the last picture, but that thoy slope gradually, like the sides of a cup. The holes in the lamina cribrosa can be seen very distinctly in the floor of the excavation. Compare with this the pathological drawing. Fig. N, page 56. 66 Tab. 8. Fig. 14. Fie. 15. PLATE IX Fig. 16. Atrophy of the Optic Nerve after Occlusion of the Central Artery Fig. 17. Partial, or Temporal, Paleness of the Optic Nerve Fig. 16. Atrophy of the Optic Nerve after Occlusion of the Central Artery (Sue JKlgL' 55) The papilla is white, its margins arc fairly distinct, its level is the same as that of the retina, its veins are of apj)roxiinately normal size, its arteries are tlireatilike. In the vicinity of tlie optic nerve is to he seen again un uneven coloriiif^ of the fundus as the consequence of an immigration of pigment into the atrophic retina. In the macula is to be seen, framed in pigment, a coronula of little bright points, which is characteristic of an occlusion of tlie artery that took place at some previous time (see page 127). The vision of this eye was totally lost. As a general rule the arteries are completely empty of blood for a few days after the occlusion, and then gradually refill from the ciliary vessels by way of Zinn's arterial plexus (see page 168). » Fig. 17. Partial, or Temporal, Paleness .of the Optic Nerve (See page 58) The margins, vessels and level of the papilla are normal, but its temporal half exhibits an abnormal paleness that far surpasses the ordinary difference in color of the temporal from the nasal portion. This patient had at the same time a central scotoma. The neurological examination revealed that he was suffering from nmltiple sclerosis. The loss of vision caused by the central scotoma was the only subjective symptom of which he complained. The discovery of the temporal paleness led to the neurological examination that disclosed the presence of this serious disease. 68 Tab. 9. hi", in Fiar. 17. Abnormal Redness of the Papilla. Optic Neuritis, Retrobulbar Neuritis, and Choked Disk Abnormal Redness of the Papilla, Optic Neuritis, Retrobulbar Neuritis, and Choked Disk I. Redness of the Papilla by Itself without any other symptom is a condition that must be considered with ex- treme care, just the same as paleness, because the color of the papilla varies phi/aiologicaUi/ within rather wide limits and, moreover, is dependent on a number of secondary factors, with which it is necessary to be acquainted in order to estimate correctly the influence they exert. A papilla always appears redder in a blonde than in a brunette fundus ; it appears to be redder when the light used is saturated with red rays, as for example that from a kerosene lamp; it looks rodder in young than in old persons. It must also be remembered that a hyper<-emia of the papilla may be induced by a pro- longed examination with the ophthalmoscope, or by severe accommodative efforts in hypermetropes and presbyopes. Aside from these causes, which may be termed physiological, there is a hyperajmia which appears as an accompani/ing symptom of morbid processes, as in inflammations of the anterior and posterior segments of the eye, espe- cially in iritis and iridocyclitis, in injuries of the eyeball, in empj'emata of the accessory sinuses, and in such circulatory disturbances as are caused by heart disease, or by tumors of the mediastinum, although the optic nerve itself is not diseased. The bearing of all these possibilities nmst be recog- nized and correctly estimated before a hypenfmia can be decided to be the iorcrunner of an optic neuritis, or of a choked disk. Finally, a particular form that is extremely apt to give rise to mistakes, and consequently has been termed pseudoneuritis, demands a special consideration. Pseudoneuritis may appear with an obscuration of the margins of the disk, with engorgement and tortuosity of the vessels, and even with a slight prominence of the papilla, anil yet the condition is not pathological, but congenital. Hypermetropia, or hypermetropic astigmatisni, is commonly present in these cases, ana, as these conditions of refraction sometimes impair the vision, another symptom of true optic neuritis may be added, viz., the impairment of the vision. But pseudoneuritis can be positively differentiated from optic neuritis by the absence of the oedema about the pajiilla. which is present in almost all cases of optic neuritis and is always absent in pseudoneuritis. The presence of hemorrhages, or of disturbances in the field of vision, renders the diagnosis of optic neuritis certain, but these symptoms are absent in many cases. 71 II. Optic Neuritis The difTcrentiiition of pseudoneuritis from optic neuritis is of so much the greater ini])ort- red i and cloudy par- tially or wholly ob- scured little or no eleva- tion arteries little changed ; veins broad and tor- tuous always present rarely present usually much inii>aircd a central scoto- ma often present Choked disk great elevation arteries small, veins enlarged; great dispro- jxtrtion in size between the veins and the arteries always present usually present normal for a long time, of- ten with tran- sient obscura- tions variable; nor- mal, concentric contraction, sectorlike sco- tomas, hemian- opsia . Pseudo- Deuritis little or no eleva- tion arteries normal, veins often broad and tortuous never present never present normal, or im- paired in conse- quence of hypernietropia or hypermetro- pic astigmatism normal ' For albuminuric choked disk, see page 79. Aside from the forms of disease which even the expert finds difficult to ditferentiate, the diag- nostic difficulties that arise may be avoided easily by proiier techiii(|ue and attention. 1. Inaccurate focussing upon the ophthalmoscopic picture. No one makes the diagnosis of optic neuritis more often than a neo])hyte in ophthalmoscopy, who has not yet learned to accommo- date correctly upon the picture of the fundus and mistakes the papilla, which seems to him in- distinct because of his faulty accommodation, for one that is pathologically changed. Usually the examiner is easily able to change the indistinct i)icture into a distinct one by moving his head back- iiard or forirarrl, keeping his accommodation unchanged (see page 5 •. 2. Delicate, diffuse opacities of the cornea and lens may likewise cause confusion by making the papilla api)ear indistinct. 'I'his errnr is e.isiiy avoided by an examination of the eye by oblique illumination, or by throwing light into the ei/e u-ith a mirror, which should be made in every case previous to an attempt to see the fundus. The source of error is not so easily to be detected in ,S. Diffuse opacities of the vitreous. Usually it is extremely difficult to see these, but we may be aided if we examine the peripherv of the fundus, as we alwaj-s should. The cloudiness and obscuration caused by the oedema in optic neuritis extends at most one or two papillary diameters into the retina, which then assumes its normal character. The periphery of the fundus is normal in optic neuritis, although it may be obscured by opacities in the vitreous. When the latter are present, together with an optic neuritis, we have to take very careful note of the vessels, of any hemorrhages that may be present, of little patches of degeneration, and of the condition of the field of vision, as, for example, of the presence of a central scotoma, in order not to err in the diagnosis. 4. Detachments of the Retina that are situated not too far from the papilla may give rise to a confusion with a partial, or a total optic neuritis, through an accompanying oedema that reaches to the papilla, a cloudiness of the retina, and a tortuosity of the vessels, but this error also may be avoided by an examination of the periphery and of the field of vision (see page lol). This possibility must always be borne in mind. 5. Commotio retinae, when it affects the vicinity of the optic nerve, may sometimes give rise to an error (Fig. 43). at l( ast at first glance. The abs influeiice on the prof^nosis. Under proper treatment it usually runs a l)enign course. 6. The forms of optic neuritis that are caused by abscesses in the orbit and empficmxis of the accessory sinuses show a marked contrast to the otoge- nous in that the disturbance of vision, a central scotoma which is often very large, mav be (juite considerable at a time whiii scai-crly anytiiiiiir wrong can be seen on the optic nerve. The prognosis is usually good when the diseased cavities are opened at the proper time, yet it must be made with some reserva- tion. Sometimes these forms of optic neuritis resemble in their course tlie axial, which is described below, sometimes a marked choked disk. In many cases of abscess of the orbit a thrombosis of the retinal vessels is produced, which can be recognized by the deep black color of the colunms of blood and the absence of the pressure pulse (see page 107). 7. Si/mpatJtctic optic neuritis is a very rare phenomenon, but when it is met with it is usually in company with the characteristic roundish patciies in the ciiorioid illustrated in Fig. 40. 8. No other forms of optic neuritis have anv distinctive characteristics; it is necessarv to relv whollv on the results of the general examination in order to determine their etiology. III. Axial Optic Neuritis ' (Neuritis fasciculi papillomacularis ; Toxic neuritis; Retrobulbar neuritis.) An ophthalmoscopic picture of this condition is not presented in the atlas, because no change is produced in the appearance of the head of the optic nerve in 95% of the cases of the disease in question, and in the re- maining 5^ the only change is a little hypera'mia and engorgement, at least in the chronic cases. In acute poisoning with methyl alcohol more marked symptoms are to be seen, some resembling a partial atrophy, some a choked disk. Individual cases present an atroph}' of the head of the optic nerve that is demonstrable on tiie third day. The diagnosis is possil;le in all chronic cases only through the demonstration of certain subjective symptoms. The disease usually begins suddenly with a visual disturbance which permits the patient to orientate, but precludes the distinct perception of fixed objects, and especially renders it impossible for him to read. If he is then examined with the perimeter, or with Haitz" charts, the demonstration of a central scotoma is fairh' eas3^ The examination with colors is particularly impor- tant ; the color of small green and red objects cannot be recognized centrally, but they appear to be gray or "dark," while it is perceived at once by periphe- ral vision, i.e., as soon as the patient looks to one side of the object. The ' The neuritis may be considered to be secondary, or ascendincr in this disease, the origin of which is a destruction of the ganglion cells of the retina, as has been proved by the pathological examination of persons poisoned with methyl alcohol dur- ing the past year in Berlin. 79 perception of yellow and of blue is also lost in the later stag's, hut the de- monstration of a central scotoma for green and red in the beginning is decisive as regards the diagnosis. The size of the central scotoma is not absolutely dependent on the extent of the area of distribution of the paiiillomacular bundle; it ma}^ be smaller than this, as in diabetes, or it may be considerablj' larger when the adjacent parts of the optic nerve are involved, especially in diseases cf the accessory sinuses. At first there is usually nothing to be seen with the ophthalmoscope; it is not until the process passes over into atrophy that a paleness of the temporal side of the optic nerve is to be seen (see page •58). The same diseases are to be taken into account etiologically, as in par- tial, or temporal, atrophy of the optic nerve, diseases of the accessory sinuses, intoxications, and multiple sclerosis (see page .59). It should be remembered that a number of diseases, such as empyema of the accessory sinuses, lead poisoning, and diabetes, may induce the picture of either true optic neuritis, or of axial optic neuritis. The prognosis depends on the cause and the stage of the disease. When it is possible to induce an alcoholic to abstain from liquor his vision may return, otherwise his optic nerves will become permanently atrophic. The prognosis is not so good, though it is not absolutely bad, in cases of poisoning with sulphuretted hydrogen and carbonic oxide: it is ratlier better in diabetes. Note. — The charts devised by Haitz are extremely useful for the de- monstration of a central scotoma. These charts consist of symmetrical halves with graduated lines and can be used in an ordinarv stereoscope. The two halves of the chart are superimposed by tlie action of prisms so that they fuse into a stereoscopic picture and appear as one. This enables the healthv eve to maintain an accurate fixation while the other is tested for the presence of a central scotoma. IV. Choked Disk There is as yet no universally accepted theory as to the nature of the origin of choked disk, it is still uncertain whether it is caused purely by engorgement, or by inflammation. This question is of comparatively little importance to tlie clinical picture of at least one form, the so-called albuminuric choked disk. It deserves to be particularly mentioned, on account of its great etiological Importance, that in exceptional cases albuminuric neuritis may assume a form that can scarcelv be differentiated from a clioked disk witli patches of degeneration. Arterio- sclerotic optic neuritis also has the appearance of a choked disk in many cases. The most essential points of difference between an optic neuritis and a choked disk consist in : 1. The behavior of the vessels. In clioked disk there is a verv consid- erable difference in the fullness of tlie veins and of the arteries; the veins 80 are distended, the arteries contracted, wliile in optic neuritis tlie arteries are almost normal and the veins overfilled. 2. The elevation of the juad of the optie nerve.' A choked disk is accus- tomed to rise more than 1 nnn, *i D, above the level of the retina, while a disk that is the seat of a neuritis seldom reaches such a height. 3. The beh.ivior of the vision. In optic neuritis the vision is usually much impaired at a very early stage (central scotoma), while in choked disk it may remain nearly, or (juite, normal for a long time. The course of a choked disk is ;is follows, according to v. Miclirl: At fir>t the arteries are seen to become .small and to be provided with broad reflex stripes u})on the papilla. The large venous trunks are much broadened, tortuous, of a dark red color, and are destitute of jiulsation. The smaller veins become more distinct bcc.-iuse of their greater fullness. The vessels in general, but particularly the veins, appear to be bent and broken on the other side of the margin of the papilla ; a large number of small vessels very often become visible on the pa])illa itself (I'ig. 25), and give it a reddish gray tone of color that often inclines to violet. The papilla forms a marked elevation with a precipitous descent to the retina, and exhibits an increasing opacity with radiating lines, which covers its margins, extends out beyond them, and is bordered by ;i gray edge. The excavation may persist for a while (Fig. 24), or only a part of the papilla may be affected (Fig. 23)- In its further course the elevation and swelling of the pay)illa increases, the retina in its immediate neigliborhood becomes more and more opaque, and consequently gives the impression that the papilla has become broader, because as the result of its indistinct contour its margins seem to lie where the opacity ceases. The opacity of the papilla and of its immediate vicinitv exhibits more and more a striated and reddish white appearance cor- responding to the normal course of the bundles of nerve fibers in the retina. Often the vessels can scarcely be perceived in the center of the papilla, but come into view first in its periphery, or at the margin of the opacity, from the swollen tissue. The arteries appear to be still more contracted than at first, drawn out and ])ale. the veins, beginning with pale, pointed ends, show a deep, dark red color, have diameters tliat vary a great deal according to the depth at which they are situated, and l)i'nd about with great windings in the plane of the retina, in which they run tortuous courses. Frequently the vessels ai-e hidden, or obscured, for a distance by a gray opacity, and hemor- rhages are often found arranged in radi.il stria', usually in the retina at the margin of the p;ipilla, as well as here and there in the latter itself. Fine, brilliant white lines, ordinarily arranged radially, on and also outside of the papilla, or small, brilli-mt white spots, which appear at a very early period, are chiefly to be observed in cliildi'en or young people. These lines and spots often extend beyond the margin of the papilla and maintain such ' Coneerninfr the way to estimate ditTcrences of level, see page 9. 81 an extent and groupiiitr tliat tlio retina may present the same condition as in albuminuric retinitis. Sometimes the veins are accompanied by white stripes. Gradually tlic papilla loses its reddish tone of color, which is replaced by a white, or yellowish white opacity, inclining to gray, but its margins remain obscured and the swelling continues to be plainly demonstrable. The onset of these changes ushers in the so-called atrophic stage (Fig. 13) of clioked disk, in which the protrusion of the papilla subsides. The opacity and swell- ing do not undergo complete involution, the arteries remain small, the veins engorged. Just as only one half, or one sector, may be swollen at first (Fig. 23), so in the involution of the swelling the subsidence may take place in the same way. Not infrequently the pigment epithelium in the region of the opaque margin of the optic disk is decolorized. What Etiological Conclusions can be Drawn from the Ophthal- moscopic Picture of Choked Disk? Unilateral Cliol'id Dislc occurs in affections of the orbit, such as tumor, abscess, cysticercus, and gumma, and in diseases of the accessory sinuses. It must be remembered that tumors or abscesses in the middle fossa of the skull may protrude into the orbit. Bilateral Chohed Disk occurs in all conditions of the brain that reduce the amount of space in the cranial cavity. Chief among these are all kinds of tumors of the brain. including not only the true tumors, but also cysticerci, aneurysms, gum- mata, and tubercles (about 70 to 80"^). Choked disk is absent in onh' from .5 to 10% of the cases of tumor of the brain, and these are mainly tumors of the frontal brain and of tlie hypophysis. The fartiier back the tumor lies the more certain is a choked disk to appear. A very rapid onset of visual disturbance, with a high degree of choked disk and severe pains in the back of the head, is indicative of a gumma in the cerebellum ; a clioked disk with disturbances of the auditory and facial nerves, of a tumor in the angle between the cerebellum and the pons. A disturbance in the field of vision, like a hemianopsia, frequently gives an indication as to the situation of the tumor. A choked disk with horizontal hemianopsia may bo caused by a hydrocephalus internus with a bulging outward of the recessus infundibuli and pressure of the same upon the chiasm. A localization of a brain tumor from the greater development of the choked disk in one eye or the other cannot be made, but it may perhaps be possible from the accom- panying faults in the field of vision, such as a homonymous hemianopsia. The cause of choked disk next in importance to tumor of the brain is serous meningitis, or h/jdroccphalus internus. None of the other causes, such 82 as oxjccphalia, abscess of tlio hrain, sinus tluomljosis, and liLinorrliagic pachymeningitis, art' of iqual c'oiisi([iuiice. In the disease last mentioned the choked disk is sometimes unihiteral and associated witli dilatation of the pupil. The affections of the optic nerve observed in hemorrhages into the sub- dural, or subarachnoidal space, do not correspond entirely with the {)ieturc of choked disk, inasnuieh as the dispropoi'tion between tiu ai-terii's and the veins is not apt to be so marked. The aft'ection is usually more ])ron()uneed on the side of the lesion than on the other. Finally, a choked disk may result from an obstruction to the outflow of Fig. p.— Choked Disk. In this picture, taken from the textbook by Roemer, the mushroomlike elevation of the papilla into the vitreous, and the great distention of the sheath of the optic nerve, are to be seen very distinctly. the venous blood into the cavernous sinus. Concerning the thrombosis of the vessels of the retina see pages 78 and 102. Such a cause is supposed to be present in the choked disk of chlorosis. In conclusion it remains to be said that albmninuric and arteriosclerotic optic neuritis may present the picture of choked disk, in consequence of the engorgement that takes place at the same time. Therefore the urine should be examined and Wassermann'.i test he made in every case. The vision may remain normal for a long time, and therefore be at variance with the great ophthalmoscopic changes. When the choked disk passes into the atrophic stage the vision gradually disappears, but from the first the patients are tormented by temporary, fleeting attacks of blindness, or of obscuration. 83 The field of vision shows various forms of contraction. Tlic defects may be peripheral, or in the form of sectors, or of hemianopsia, but such a central scotoma as accompanies oj)tic neuritis is almost never seen. Tumors are rarely met with on the papilla ; the most common are gummata and tubercles. A conglomerate tubercle is shown in Fig. 19. Sometimes developments of connective tissue are seen to extend out from the papilla; these may be the remains of fetal structures, the results of injuries, or the products of organization of hemorrhages. Hemorrhages on the Papilla may appear in optic neuritis, or in choked disk, or when the vessels of the retina are sclerotic. Sometimes they result from injuries to the .eye, or to the optic nerve. Tlie demonstration of a hemorrhage, when it is not of traumatic origin, is always of great diagnostic importance. For example, it immediately decides the question in a doubtful case of optic neuritis or pseudoneuritis in favor of the former (see page 71). ]\ our, (Is of tlie Optic Nerve in the orbit produce an ophthalmoscopic picture that varies accordingly as the nerve is severed in the portion that contains the vessels, or in the part that does not. In the former cases the signs of an occlusion of the central artery are present (see Fig. 44, ;uul page 150). in the latter case the optic nerve appears to be perfectly normal in spite of the blindness, until atrophy gradually develops, in the course of about 6 weeks (see Fig. 10, and page 54). PLATE X Fig. 18. Optic Neuritis Fig. 19. Tubercle at the Entrance of the Optic Nerve Fig. 18. Optic Neuritis (See pages 72 and 75) The margins of tlic optic disk arc quite indistinct, tlic disk itself is much reddened and is surrounded by a gray areola, due to a'dema. The veins are much distended and are slightly hazy in the gray zone caused by the retinal oedema. They are acconijj.uiicd l)y whitish stripes on the papilla. A slight elevation of the disk can be made out by parallactic displacement, or by de- termining the refraction with the ophtiialmoscope. Tiie condition was due, in this case, to syphilis. The gray ring about the papilla is of sjx'cial value in the diagnosis (see page 72). Fig. 19. Tubercle at the Entrance of the Optic Nerve (See pages 76 and 83) The larger part of the papilla is obliterated, its margin on one side is completely hidden. At that jjlace is a whitish mass, nearly as large as the papilla, which is shown by j)arallactic disj)lacenicnt to be distinctly elevated. It is surrounded by a slightly gray discoloration of the fundus, caused by an a'dema of the retina. The retinal vessels that end at this place y)lunge into the mass and their terminal portions are invisible. It is striking that no superior temporal artery cm l)e seen. The fundus is of the albinotic type and is normal, except for the gray discoloration in the vicinity of the lesion; the retinal vessels elsewhere are normal. The diagnosis in this case was that of a tumor at the entrance of the optic nerve. The specific diagnosis of a tubercle, or of a conglomerate of tubercles, in the head of the optic nerve, was based upon the local reaction that followed an injection of tuberculin. 8fi Tab. lO. Fig. 18. Fig. 19. PLATE XI Fig. 20. Albuminuric Optic Neuritis (Albuminuric Choked Disk) Fig. 21. Optic Neuritis Undergoing Involution Fig. 20. Albuminuric Optic Neuritis (Albuminuric Choked Disk) (See page 7G) Tlic papilla is very red and swollen, its margins arc obliterated, its arteries reduced in size. It was mistaken at first for a choked disk caused by a tumor of the brain, but, as the result of the neurological examination was negative, and the urine presented the characteristics of chronic nephritis, that diagnosis liad to be abandoned and replaced by that of an albuminuric neuritis (sec page 79). At some distance from the papilla may be seen hemorrhages phiced radially, therefore superficial, and some stipplings that indicate patches of degeneration on the temporal side. These patches of degeneration are not inconsistent with a typical choked disk, for the}' arc sometimes found in asso- ciation with it, but they are to be seen more commonly with neuroretinitis albuminurica. The fundus, which is on the whole of the uniform, stipjiled type, approaches the tessehited in its nasal portion. Tile absence of the stellate figure in the iiiaculn is in no way contraiiidi- cative of albuminuria, for it is present in by no means all cases of albuminuric diseases of the retina. Fig. 21. — Optic Neuritis Undergoing Involution (See pages 7-i and 76) The margins of the papilla have already become rather more distinct. The color is a cold red in the center, while the marginal portions are paler. The vessels are distinctly sheathed. Pigment has migrated into the retina around the optic nerve, which accounts for the dark gray discoloration. Such a picture as this may also be indicative of the so-called arterioscle- rotic optic neuritis, a form of inflammation of the optic nerve that is met with in old people, and is characterized by a verj' sluggish course of little intensity, in which the changes in the retinal vessels stand in the foreground. 88 Tab. II. Fig. 20. Fig. 21 PLATE XII Fig. 22. The Optic Nerve in a Case of Sinus Thrombosis Com- plicating an Otitis Media Fig. 22. The Optic Nerve in a Case of Sinus Thrombosis Com- plicating an Otitis Media (See piigc- 77) A slitrlit liypei-.Tiiiia of tlic papillu is soiiictinu's seen in iincomplic.itcd cases of otitis media, but as soon as a ciTcbral complication takes place, such as a sinus tlironibosis, an extradural abscess, or a meningitis, the redness of the papilla becomes greater without causing the margins to become particularly indistinct. The veins show only a trifling congestion. What is specially no- ticeable is the enormous (rdema of the retina which surrounds the head of the optic nerve and hides evirything that lies beneatli it. The retinal vessels may rise through the (edema and show a distinct parallactic displacement; when they are placed more deeply they are partially covered by the oedema, as is the case with the vessel situated above in the picture. The (edema is very clearly visible in this case because it is quite extensive, and because tlie almost albinotic fundus shows up many details that are lack- ing in the o'deniatous portion. The wdema cannot be seen as well when the color of the fundus is uniform. As soon as changes that are to some degree distinct have appeared in the head of the optic nerve it becomes the duty of the aural surgeon to open thq skull. This operation is sometimes followed by an exacerbation of the intra- ocular condition, but the prognosis of this is not bad. 90 Tab. 12. Fig. 22. PLATE XIII Fig. 23. Commencing Choked Disk Fig. 24. Commencing Choked Disk Fig. 23. Commencing Choked Disk (Sl'u pa^re 80) It is important to be rJilc to recognize tiie early stage of a clioked disk on account of its significance in diagnosis. It can be seen from the course of the vessels that the temporal portion of the papilla, where the nerve fibers are feebler, has not yet been driven for- ward, while the nasal is distinctly elevated. The oedema that causes the ele- vation has already invaded the vicinity so as to make the papilla appear to be enlarged and to completely obscure its margins. The veins are distended, while only a part of the arteries show tliat their caliber is diminished. Fig. 24. — Commencing Choked Disk (See page 80) This picture shows another form. The entire periphery is protruded, while the center still remains at its old level. The disproportion between the arteries and the veins is clearly marked, as well as the oedema that surrounds the papilla. 92 Tab. 1». Fig. 23. Fig. 24. PLATE XIV Fig. 25. Old Choked Disk with a Very Abundant Development of Vessels Fig. 26. Choked Disk at Its Acme Fig. 25. Old Choked Disk with a Very Abundant Development of Vessels (Sec page 81 ) Two forms of cliokc'd disk can be distin^iished in well-marked cases, one distinctly knob-shaped, the other more diffuse. The former is shown in this picture. The delimitation of the swollen portion from the retina is comparatively tlistiiict. althoiiirji the protrusion is considerable, as may be seen from the course of the \essels. and (edema is also certainly present. The disproportion between the arteries and tlic \eins forms the principal ground for the diagnosis. On the papilla are to l;e seen a large number of newly formed vessels; this indicates that the choked disk has lasted a long time. The oilier papilla of the same patient, which was distinctly atrophic, is shown in Fig. 22. The lesion in this case was a ii'liosarcoma of the eei'(l)elluni. Fig. 26. Choked Disk at Its Acme (See page 80) The more diffusi' foi'in is shown in this picture. Scarcely a trace can be seen of the margins of the j)apilla. hut the latter seems to send tonguelike processes into the retina. The ])aj)illa is distinctly elevated, as can be seen from the course of the vessels, and exhibits a radiating striation. A num- ber of hemorrhages, also striate in form, give the disk quite a specific appear- ance. The disproportion between the arteries and the veins is so great at the acme that tiie former are scarcely visible, while the latter leave the papilla as broad, tortuous bands. Some white patches of degeneration are visible in the retina. There ai'e only a few retinal hemorrhages in this case, but they are often much more numerous. The vision in this ])atient was normal. The neurological examination revealed the existence of a tumor in the angle between the cerebellum and the pons, the so-called acusticus tumor. 94 Tab. J4. Fio. 25. ¥U'. 26. Vessels of the Retina Vessels of the Retina Tlie great diagnostic inipoi-tanci' of changes in the vessels of tlic retina has already been pointed out in the study of the diseases of the optic nerve. Nowhere else in the hodv can the lilood vessels be seen so clearly, nowhere else are they so accessible to direct observation, nowhere else is our duty so imperative to study the minutest details of the picture, as in the vessels of the retina, the more so that they are offshoots from the vessels of the brain, and that certain conclusions can be drawn from their condition with refer- ence to that of the cerebral vessels. Bouchut termed ophthalmoscopy direct cerebroscopy, and, although this expression overshoots the mark, it indicates how highly ophthalmoscopy is to be valued (compare page 153). A special chapter is devoted here to changes in these vessels in order to indicate their importance in the most forceful manner, and to lead to their careful observation. In many cases the sequela of diseases of the vessels stand forth in such a manner, as, for example, in Fig. 44, that a certain schooling is needed to think of, and correspondingly to investigate, the cause of such changes ; in others, as in Fig. 28. the changes in the vessels themselves are so prominent that they explain tjie clinical picture. Wc should therefore not he content to cast a brief glance at the papilla in an ophthalmoscopic examimition, but shauld accustom ourselves to investigate the vessels of the retina very thor- oughly. The changes relate chiefly to the caliber and walls of the vessels, more rarely to their contents, and. uiukr certain circumstances, pulsatory phe- nomena are to be taken into account tliagnostically. Preliminary Remarks on the Anatomy It must he remembered that tlie walls of the retinal vessels are perfectly transparent, and therefore invisible, when they are in a normal condition: also that under some pathological conditions, as, for example, in hyaline de- generation, they may be perfectly transparent in spite of a considerable thick- ening that is made evident only by a narrowing of the blood column. Tlm^ what is seen ophthalmoscopically is not the entire vessel, but only its eon- tents ; the wall has to be added mentally, so that the vessel is really twice as thick as it appears to be in the ophthalmoscopic picture. On the other hand, defects a])pear in the transparency of the vessel wall which may be observed in all ilegrees, from a scarcely perceptible veiling to a 07 98 coiiipk'tc opacity. Tlio color ussiiiiud \)\ tlic noscI may then he a j)urc wliitc, a »'rav wliitc, ii yellow white, or a liirht hrown ; lioth the o|)acity and the reflection iiwiy be fairly variable. In the observation of the transverse iliainetcr of the vessel the observer is subject to many illusions, which are due not only to the optical conditions presi'iit in the eve, but also to thi' more or less dee[) situation of the vessel in the retina. The apparent size of the ])apilla must serve as the unit of measure. The Changes in the Vessels of the Retina take place in A. The caliber: T^ifferentiation must be made between 1, Contractionn, up to total disappearance of the vessels, 2, Diliifiitions, 3, Dijfcrciiccs in the projiortioinitc ciililiir of the arteries and of the veins, ■i, Vncvcrnuxscs in the caliber of individual vessels. B. The color: Tlie chancre of color may be tlue to (a) the color of the blood column, (b) the color of the k'iiU of the vessel; in regard to this are to be noted 1, accompanying stripes, 2, transformation into white cords, 3, infiltrates in or over the vessels. C. The number and arrangement. D. The course; drawn out, tortuous, wavy, broken. E. The reflex; its breadth and intensity. F. The phenomena of pulsation. ELABORATION OF THE ABOVE SUMMARY A. The Caliber 1. ConiracHon. A change in the length of a vessel is usually associated with a decrease of its transverse diameter; at first it is drawn out, later it is distinctly short- ened. The refiex and the color are also apt to be changed. Four forms are to be distinguished ctiologically : (n) That which is produced pathologically, commonly termed sclerosis; (?>) that which is functional, caused by contraction of the muscular tissue in the wall of the vessel ; (r) that which is due to compression, the cause of which is to be sought in a compression of the afferent vessels ; (J) that which is due to an imperfect filling of the vessels with blood. 99 The first form, .sclurosis, is tliu most coimiion. x\s appears from tlie above remarks on tlie anatomy, the contraction is usually only an apparent one; of such a nature that the transjjarciit, and therefore invisible, wall of the vessel is thickenetl so as to render the blood tohunn within it smaller, but true diminutions and atrophies of the vessels themselves are met with. It is not usually possible to distinguish the two forms opiitliahnoscopifully. As considerable differences occur normally in the caliber of the vessels in different persons, and as the vessels in the same person vary in size one from another, it is often quite difficult to determine whether a commencing sclerosis is present or not. In such doubtful cases attention has to be paid to fiuctua- tions in caliber,' to abnormally distinct pulsation, and to the sheathings that may perhaps be present. These conditions are almost always to be held to indicate a commencing sclerosis of the vessels, the extremely rare congenital sheathings being excluded. If the sclerosis is more advanced, for example, as in Fig. 67, no further difficulties are encountered in its diagnosis. As may be seen in Fig. 56, the change may go so far as to render the vessels no longer visible. The changes may take place in both the arteries and the veins, cither in- dependently of each other, or together. In the latter case the physiological difference in the breadth of the veins and the arteries is maintained to the last, so that when the vessels disappear the arteries are the first to become invis- ible. In the majority of cases the arteries alone are affected, while the veins at first seem to be rather broadened on account of the elasticity of their walls. As complications, or sequela?, may be named atrophy of the optic nerve (see page 53 and Fig. Q), acute occlusion of the arteries with its consequences (see page 1.50 and Fig. 44), thrombosis of the veins (see page 117 and Fig. 27), iind extensive disease of the retina in the form of retinitis albuminurica (see page 133 and Fig. 31), or diabetica (see page 131- and Fig. 35). Etiologically, the first disease to be taken into account is syphilis, either acquired (Fig. 38) or hereditary (Fig. 56), then arteriosclerosis (Fig. 67), chronic nephritis and diabetes. The high degree of contraction of the vessels found in retinitis pigmentosa (Fig. 51), which afifects both the arteries and the veins, depends on similar causes to all appearance. Contrac- tion of the arteries alone is to be observed as a sequel of an old occlusion (Fig. 16), and sometimes also in old cases of glaucoma. A uniform functional contraction of both the arteries and the veins is found in cases of poisoning with quinine or ergotin, in chronic alcoholism and in commencing syncope. A compression of the arteries is associated regularly with a compression of the veins, but while it shows itself in the arteries by a diminution of the blood column due to an insufficient supply of blood, it causes an engorgement ^ The apparent diminution of the vessel to a point at the place where it leaves the papilla is not to be understood as a fluctuation in caliber in this sense. 100 of the veins by obstructing tlic escape of tlie blood. We iiuct uitli coniprcs- .sion cbicfly in cases of tumor of the orbit and affections that ri(hiee the space within tile skulh In tiie former it is unilateral, in the latter bilateral. As the venous entjorgenient forms tlie most conspicuous jiart of the picture, this con- dition will be described below, under Dilatation of the \'es.sels. A contraction of the arteries takes place in cases in which there has been a great loss of blood, as in labor, from ulcer of the stomach and from wounds, but this usually passes off very quickly after the hemorrhage has been checked, ,ilt hough a more or less severe functional disturbance of the vision persists in many cases, which is due to a partial or total atro])hy of the optic nerve. 2. Dilatations of the Vessels. Just as a straightening accompanies the contraction of a vessel, so a marked tortuosity is commonly associated with its dilatation. The reflex and the color of the blood column arc also accustomed to undergo a change, the former becoming broader, the latter darker (see Fig. 28)- Both arteries and veins may be dilated at the same time, or the veins alone may be affected. A dilatation of the arteries alone is not likely to be ob- served. If the dilatation involves both the arteries and the veins the normal difference between their transverse diameters is maintained. The color of the fundus is not changed by the increased fullness of the vessels, on the con- trary the papilla takes on a livelier color. The vessels seem to be increased in number because the smaller ones, which are usually invisible, come into view. At the same time it must be remembered that under certain circum- stances the number may seem to be smaller than normal, as is the case when there is coincidently a great deal of oedema ; for example, as in a neuro- retinitis ; the smaller and deeper branches may then be buried completely in the oedema. (rt) Uniform Dilatation of the Veins and Arteries is met with as a local symptom of general plethora in fevers, in constitutional anomalies, such as plethora, or the apoplectic habit, and in overindulgence in alcohol. Ocular causes to which it may be due are the sudden relaxation of tension caused by operative or accidental wounding of the eyeball, the relief from pressure, as in operations for strabismus, and as the result of local conges- tion produced by contusions, by a downward inclination of the head, by too nnieh light, as when an ophthalmoscopic examination is prolonged unduly, or by too great demands having been made on the acconmiodation. It is likewise met with in inflammation of both the anterior and posterior segments of the eyeball. In this respect inflammation of the optic nerve is to be mentioned as of special importance (see Optic Neuritis, page 72), 101 It is considered by sonic authors to be an early symptom of disease of the accessory sinuses which may be tlie very first to appear. It is also to be noticed as the first sign of a cerebral complication, or of a sinus involve- ment, in diseases of the ear. In Ieucoc3'thffmia the veins are apt to be enormously dilated, while the dilatation of the arteries is only moderate. The color of the fundus in these cases is orange red. (Ii) Venous Hyperaemia with the Arteries Normal or Con- tracted A'enous hyperaemia is present in general cyanosis due to congenital, rarely to acquired, heart disease, as well as in pneumonia, emphysema, and poly- cyth.Tmia. It is due to local causes: (a) In the early stage of plilebosclerosis ; contraction ensues in the later stages. (/3) In acute glaucoma (Fig. 14, pulsation of the arteries, varicosities of the veins), and in secondary glaucoma, for example, from an intraocular tumor (Fig. 50)- (y) In thrombosis of the veins (Figs. 27 and 28)1 the most essential and most prominent symptom in which is the enormous hemorrhages. (S) In inflammation of the head of the optic nerve (albuminuric choked disk) and of the retina (Fig. 20, page 79). (e) In compression of the vessels, either directly by tumors of the orbit, when it is unilateral, or by processes that increase the pressure in the brain, when it is bilateral (Fig. 26). The dilatation of the veins may be so considerable as to make them appear to be from one quarter to one and one half times as broad as normal. It is to be noticed in those affections which are accompanied by an oedema of the retina that the vessels are sometimes so embedded in the oedema that only a portion of their transverse sections can be seen. 3. The Differences in the Proportional Sizes of the Arteries and of the Veins have been dealt with in the preceding chapter, and tlie only thing necessary is to call attention again to the great importance of this point in the differ- ential diagnosis of optic neuritis from choked disk (page 79). 4. Unevennesses of Caliher in the course of individual vessels may be real or only apparent. Real inequalities may be caused by uneven scleroses of the walls; uneven in both the sense that the sclerosis is more marked in some places than in others, and the sense that the wall of the vessel is thickened more on one side than on the other, so tliut the Uinieii is displaced from tlie center of the vessel, or is made oval. As scleroses may affect tlie wall of the vessel witiiout producing any opacltv in it, and as the breatitli of the vessel fluctuates within fairl}' wide limits under physiological conditions, especial weight is to be placed on such tmevennesses of cuUbcr in tlie diagnosis of commencing sclerosis. Secondly, the inequality of caliber may lead to greater or less pouching i out of the wall of the vessel, as siiown in those that course upward in Fig. 36, forming aneurysms of the arteries, phlebectasiie of the veins. Thrombi may readily form in the places where the vessels are pouched out. An apparent change of caliber may be produced by the embedding of the vessel in the swollen or oedematous retina (see Fig. 33), or in the tissue of tlif tumor ( Fig. 50)- A variation in caliber may also be simulated by the presence over the vessel of such tissues as medullated nerve fibers (Fig. 9). bands of connective tissue (Fig. 37), and masses of exudate (Fig. 38)- Partial interruptions in tiirombosed vessels may also simulate such an appearance. B. The Color of the Vessels is dependent on the color of the blood, of the vessel wall, and of its surround- ings. Ceteris paribus a vessel appears to be darker on a bright than on a dark background. A vessel that is buried very deeply In the retina appears to be darker than one that is superficial. The vessels are pale in ana-mia, chlorosis, and, to a very marked degree, in leucocytha'mia. In the latter disease the color of the veins is almost the same as that of the arteries, so that the former can be distinguished only by their greater breadth and tortuosity. The vessels are dark in thromboses (Fig. 28), and in venous engorge- ments of either general or local origin. In these cases the ordinary difference in the color of the arteries and the veins is particularly distinct. In cases in which the thrombosis is secondary, for example, to an orbital cellulitis, the I'essels are very dark and seem to be almost black. The change of color sometimes affects only the sides of the vessels, when it produces the appearance of accompanying stripes, sometimes its entire breadth, somctiincs only certain portions of it. The accompanying stripes may be due to various causes. Sometimes they indicate a commencing sclerosis; in these cases the blood colunui is commonly narrowed. Although they are to be seen most plainly in the neigh- borhood of the papilla they are to be found there least often, because the smaller vessels are usually diseased before the larger.^ In most cases they ^ The sheathinps of the vessel confined exclusively to the vicinity of the papilla are usually the results of neuritic changes (see under Proliferation of glia). i();3 spread out irregularly' and may have sharply defined edges, or may blend gradually with the transparent portion of the retina. Sometimes these stripes can be seen to accompany the vessel tiiroughout its entire length. In very marked cases the whole vessel may finally be transformed into a white cord (Fig. 56). The very first sign of such a disease is usually a broadening of the central, reflex light streak, after which the changes develop that have been described and the entire vessel becomes gradually transformed into a slender, white cord. Generally the color is pure white, but it may be gray, or reddish gray. The pure white color prevails in the sheathings to be described below. Pathologicallv, we find cellular and connective tissue proliferations of the intima and adventitia. The latter may lead to the so-called retinitis proliferans (Fig. 37). The sequeL-e consist of diseases of the retina and of the optic nerve, the same as in simple sclerosis, and the same etiological factors take part. As a rule the two forms of disease cannot be recognized as distinct, as the one passes over into the other ; they are spoken of here under two heads simply for the sake of clearness. Secondly, the accompanying stripes may be caused by a proUferaiion of the gVui, (IS the consequence of an optic neuritis (Figs. 12 and 21). It has already been mentioned that the indistinct margins and the white color of the papilla in an atrophy that results from an optic neuritis are caused by a proliferation of the interstitial glia tissue and, in harmony with such an etiology, this sort of sheathing is found only on tlie optic nei-ve, or in its immediate vicinity, or at least it is most pronounced in this locality. The demonstration of such a change is therefore valuable evidence in favor of the neuritic nature of an atrophy of the optic nerve. The color is commonly a pure white, in which it varies from other forms of sheathing. A third form is shown in Fig. 42. This is the one that is met with in those cases in which an acute sheathing of the retinal vessels appears simul- taneously with signs of retinitis ; it can be explained only as a filling of the lymph spaces of the adventitia with white blood corpuscles. The bright bands along the upper vessels in Fig. 33 have to be explained in a similar manner, except that here the fluid has already left the sheaths of the vessels. The white deposits of lime, and other concrements, that occur here and there, need only to be mentioned. The complete interi-uption of a vessel with the signs of a sudden occlusion (see Fig. 45) indicates the presence of an embolus, or a thrombus, within it. Sometimes the accompanying stripes are only simulated by the reflection of light along the vessels. This sort of reflection is seen very often (see page 26), especially in young persons in whom the fundus is dark. They can be recognized from the fact that they change as the mirror is rotated. Such reflections are shown in Figs. 2 and 30- 104. C. Changes in the Number of the Vessels The numbiT of vessels may be diminislied or increased. A diminution is met with in marked sclerosis (Fig. 56)) as well as in injuries and diseases of tlie retina, especially those that are associated with a development of connective tissue (Fig. 36). An .apparent diminution, due to some being rendered invisible, is to be observed when tiie optic nerve is suddenly severed througli the portion that contains the vessels, wlien arteries are occluded (Figs. 44 and 45), and when great u-dema is present, as well as in cases of tumor and of detachment of the retina. A smaller iuiihIht of vessels than lun-mal may be present congenitally, but such a condition is connnonly associated with other anomalies in the fundus. An increase in the number of vessels may likewise be real or only apparent. A true increase is caused by a new formation of large veins, or of loops of small vessels. These are to be observed when gross circulatory disturb- ances are present in the eye, as in comjiression, or partial obliteration of the central vein, i.e., in such conditions as favor the origin of a choked disk, as well as in glaucoma and after thromboses of the veins. As a rule the newly formed veins are the so-called opticociliary veins (see page 23), yet some can be seen in the retina alone. The loops of small vessels are ])articularly connnon in choked disk (Fig. 25) ; they are to be seen more rarely in diseases of the retina which are associated with a proliferation of connective tissue. They have also been observed after injuries to the optic nerve and retina. In most cases the^' lie on the papilla itself. An apparent increase is seen when vessels that are otherwis(> invisible come into view as the result of distention, or of the fact that their walls have been made visible. Such an apparent increase is seen in commencing sclerosis of the vessels, in vascular engorgement from compression of the veins or glaucoma, in leucocytha^mia, and in detachment of the retina. When the central artery is occluded the veins about the macula, which are otherwise scarcely visible, come plainly into view (Fig. 45). A surplus of vessels may be congenital, yet in most cases there is no oversupply, but the deceptive appearance is caused by the fact that the vessels which usually divide on the papilla, or after they have left it, have divided before they leave the hilus (see page 22). The presence of opticociliary, or retinociliary, vessels can scarcely be regarded as pathological ; they arc rather to be considered to be physiological variations (see page 23). The vessels which are to be observed in connection with other disturbances in the fundus, for example, with a coloboma of the chorioid. are rarely of a retinal, but usually of a chorioidal or scleral nature (Figs. 84 and 85)- 105 The division of tlie retinal vessels may present certain deviations from the normal. Thus it can be seen in many cases that some parts of the fundus usually provided with vessels are destitute of them, while other parts on the contrary show a superabundance. This condition may be either congenital, or be brought about by certain pathological processes, for example, by connective tissue formations which jiull the retina in one direction or another. The subdivision may also deviate froiii the normal as the result of the destruc- tion, or the new formation of vessels. D. The Course of the Individual Vessel shows some typical peculiarities. The vessels in myopia, especialiv when it is of high degree, seem to be nmch stretched, or drawn out (Fig. 72). On the contrary the course of the vessel is very crooked in hypermetropia, so much so that we sometimes speak of a tortuositas vasorum. The disproportion between the size of the eyeball and the surface of the retina is the cause of this peculiar behavior, but in other cases the size of the caliber, i.e., tlie fullness of the vessel, is tlie actuating cause, so that a marked tortuosity is associated with a distention of a vessel, and a stretciving, due to a simultaneous tension in its long axis, with its contraction. The careful study of the course of the retinal vessels is of extremely great importance in the determination of differences of level within tiie eve. As we look into the eye of a patient witli only one eve we cannot make use of our stereoscopic perception of depth, as tliis is dependent on binocular vision. We can perceive differences of level only by the aid of secondary means, among which the course of the vessels is a very efficient one. A number of fresh tubercles are shown along the course of the inferior temporal vein in Fig. 78; the wavy course of the vessel enables us to perceive wiiere the elevations are. In Fig. 47 is pictured a detachment of the retina: tlie folds of the detached retina may be recognized from the wavv courses of the retinal vessels. We judge in like manner concerning the conditions of level in a choked disk, in a commencing tumor, and in a proliferation of connective tissue (Fig. 23). How important the observation of the course of the vessels is in the diagnosis of glaucoma has already been pointed out on page 56. ■ E. The Reflex of the retinal vessels comes from those places that are vertical to the line of direction of the observing eye. It is strongest and liroadest on the large vessels, yet it is visible, especially in young persons, on the minute branches, although it is weak and narrow ; it is absent, however, even on vessels of medium size in senile ej'es. On the arteries it is generally brighter, more intense, narrower, and more lOf) sharply defined than on the veins, yet the reverse condition is sometimes met with. The reflex may undergo great individual iliutiiat ions, uiuln- physiological conditions, witii i-eganl to intensitv, unitoiinil \ , l)r(adtli, margins, color, aTul its comparative condition on the arteries and on the veins, whih' it cainiot be determined in the individual case what has brought about the change. Still a few important points may be noticed. The reflex is almost as useful as tlie wavy course of the vessels m the determination of differences of level, for at any elevation, no mattei- how slight, of the vessel above the level of the retina, tiie reflex disappears at the place wliere tlie bend takes place (Figs. 23, 24)- The reflex from the vessels is totally absent in detachment of the retina (Fig. 46)- The slightest extravasation or (wlema in the neighborhood of the vessel causes its reflex to disappear. Under certain pathological conditions tlir coloi- of the arteries approaches that of the veins, or the reverse, and tlun thi' reflexes will be similar to each other. The more superficial the situation of the vessel, tlie more distinct and sharply defined is tlie reflex; the dee])er the vessel, tlie less clear its light streak becomes. When the blood pressure is decreased tlie reflex becomes broader, when increased it becomes narrower. In the beginning of an arteriosclerosis the particularly intense, strikingly bright reflexes on certain parts of the vessel are the only signs of the disease. In the later course of the sclerosis, as atrophy sets in, they gradually dis- appear. There is no agreement among authors as to the cause and place of origin of this reflex. Originally it was tliougiit that the surface of the vessel itself reflected the light, hut this idea has been abandoned, as tiie result of experi- ments and discussion. The theory that meets with the most favor is the one advanced by Dimmer, that the reflex comes from the surface of the column of blood in the veins, and from the place of the axial current in the arteries. Yet objections can be raised against this theory ; Elschnig, for example, has shown that the reflex remains visible on the arteries after the circulation has ceased. F. Phenomena of Pulsation Venous and Artrrwl Pulse. Pulsation of the retinal veins is a normal phenomenon which is to be seen most distinctly in the large vessels at the iiiius, at the place where they descend into the excavation. The veins best suited for observation are the large ones that end in a point or beak at the hilus. The blood column seems to be driven backward, toward the periphery at each stroke. Two different pulsatory phenomena are included under the term pulsation 107 o/ the refined arteries: 1, the coniprussion pulse, wliicli manifests itself in a greater and less fullness during the systole and the diastole; 2, rhythmic fluctuations of caliber. The peculiar behavior of pulsation in the eye, that a venous pulse is nor- mal and that an arterial pulse is not, is explained by the fact that the vessels are subjected to an external pressure, the so-called intraocular tension, while the vessels in other parts of the body are not. The ])ulsation of the arteries is prevented by this, and the veins, which have walls that affortl little resist- ance, are compressed by it while they are less filled during the diastole. It is only when the relative conditions of pressure are changed, for example, wlien the intraoruhir tension is increased, or when the intra-arterial pressure rises abnormally high, or falls abnormally low, that an arterial pulse can be observed. The elevation of the intraocular tension can also be brought about by compression of the eyeball. If pressure is made with the finger upon the eyeball during an ophthalmoscopic examination, a venous pulse is seen at first and then, as the pressure is increased, an arterial pulse; finally, if the pressure is sufficiently forceful, the retinal vessels become completely empty of blood. The venous pulse is met with frequently in normal eyes, but usually only in young people. In old age a distinct venous pulse is indicative of a com- mencing phlebosclerosis. Absence of the pulse when the eyeball is gently pressed by the finger is a symptom of thrombosis of the central vein. An arterial pulse is always to be regarded as pathological. It indicates either an abnormally high blood pressure, an abnormally high pressure wave in the ai-terial svstem, as in cardiac hypertrophy, aortic insufficiency, aneu- rysm of the aorta or carotid, and exophthalmic goitre, or an abnormally low blood pressure, as after great loss of blood and in syncope, or, finally, an increased intraocular tension, as in glaucoma. Absence of the aortic pulse when the eyeball is pressed upon by the finger has been observed in occlusion of the central artery of the retina. Retina Retina A. Preliminary Remarks on the Anatomy In an eye that has been cut open the retina presents itself as a gray, cloudy membrane about Vs mm thick, which separates easily from the pig- ment layer and is closely connected with the subjacent tissue in only two places,^ the entrance of the optic nerve and the foyea centralis. When the retina is seized with forceps and removed from the eye the pigment layer remains in close connection witii the chorioid. Nevertheless the layer of pigment epithelium belongs embryologically and physiologically to the retina, it is the outer layer of the secondary optic vesicle. The center of the retina appears yellowish, the macula lutea, with a dark brown point, the fovea centralis. In the living, normal eye the retina is perfectly clear and transparent, so that its presence can be perceived only by means of the vessels that course in it.- The color of the fundus is therefore not influenced by that of the retina itself, but is due essentially to the greater or less abundance of the pigment contained in the pigment layer and in the chorioid ; the color of the chorioidal vessels plays a subordinate part. The peculiar color of the macula is suppressed by tliat of the subjacent tissue; it appears only a little darker than its surroundings. Its center, the fovea centralis, is still darker, because the retina is very thin at that point and consequently the chorioid and pigment epithelium show through with special clearness. The contrast with its surroundings becomes particularly marked wlien the retina in the vicinity of the macula is cloudy, as in occlusion of the central artery (see Fig. 44). The layers of the retina are known as the outer and the inner, ac- cording to their positions relative to the contents of the eye. Those lying nearest to the vitreous are called the inner layers, those more distant the outer. The outer layers, i.e., the layer of rods and cones, the outer granular layer, and the membrana limitans, which lies between them, form what is known as the layer of sensory epithelium, while the others, which occupy the inner portion of the retina, are grouped together as the cerebral layer. This is a division which is not simply anatomical, but is of great clinical and diagnostic importance, as the two layers receive nutrition from different sets of vessels. • The retina is also attached to the chorioid at the era serrata. — F. -A delicate striation, radiating from the papilla, is visible in many normal eyes; this is to be referred to the color of the retina itself. m \V2 A full and precise dcscri})Hon of the anatomy would nquin- too nuich space, so onlv thoso points will l)i' iiuntioned which ;n\- of c^)n^i(l^■^;d)lc clin- ical importance. Thr layers of nerve fibers consist of hundles of naked iiei'vc fibers which lace, as it were, into a plexus. It is only in exceptional cases tliat the}'^ have medullary sheaths and form a white s[)ot (meduUated nerve fibers, sec Fig. 9). The til)ers radiate from the papilla, with the exception of those Layer of pigment epithelium Layer of rods and cones Membrana Hmitans (. externa I Outer granular layer Outer molecular layer Inner granular layer Inner molecular layer Layer of ganglion cells Layer of optic nerve fibers ^B^S^PS^QI j Layer of pigment I epithelium j Layer of rods and I cones 3 Layer of granules / and visual cells f ^ J Outer plexiform ^ ( layer ■ '^ \ Layer of horizontal w \ cells J Layer of bipolar I cells _^ S Layer of amacrine 3- \ cells nner plexiform layer I Layer of ganglion \ cells J Layer of optic [ nerve fibers Fig. Q. Anatomy of the Retina, after Oreeff. cnniinw from its temporal side, wliicli circle in a great arch about the macula. The macula itself is supplied by particularly fine fibers which run directly to it from the temporal margin of the paj)illa (the papillomaculai- i)un(lle, see pages 1(5 and .58). The construction of the retina undergoes changes l)oth at the macula and at the periphery, which are of clinical interest. The macula is situated about ll^ papillary diameters (i mm) outward and a little downward from the entrance of the optic nerve, in the inverted image of course inward and upward, is usually transversely oval, less often rounil, and measures in its horizontal diameter l.T to 2 mm. Its margins are a little raised, and in its center is a depression with level margins, the fovea centralis. The number of the cones increases toward the fovea at the expense of the rods. To give a verv rough idea of the anatomy it may be imagined that the cone fibers, and with them their connections, are combed apart, or parteil like hair, at the fovea, so as to lav bare the cones at the bottom of the part. The peripheral portions. While the number of the cones increases as the macula is ai)])r(i.ulu(l, it decreases toward the periphery, where the rods preponderate in mnnher considerably. IJoth cease at the ora serrata. The other layers also blend at this place until only a single layer of cylin- 11 !3 driccil cells is left, hcnuatii which lies the pigment layer, with whicli it forms an intimate connection as it passes over to the iris. The nutrition of the retina is derived from two sources: 1, the central artery, 2, tlie vessels of the chorioid. The former supplies the cerebral layer, the latter the layer of nerve and pigment epithelium. 1. The principal branches of the central artcr/j of the retina run close to the inner surface of the layer of nerve fibers, or project above this into the vitreous, but are always covered by a few bundles of nerve fibers. 2. The layer of nerve epithelium is entirely without blood vessels and re- ceives its nourishment by diffusion from the capillary network of the chorioid ; the fovea centralis is likewise nonvascular, the fine retinal vessels end in a circle of capillary loops on its margin. Physiology. The percipient organs of the retina are the rods and cones, but these lie in its outer layer, toward the sclera. This gives the peculiar condition that the rays of light must first pass through the entire thickness of the retina in order to reach the organs of perception. Hence the necessity of the perfect transparency of tlie retina, and of the absence of vessels in the region of the macula. & B. General Diagnosis Ophthalmoscopic Differentiation of Di.seascii of the Inner and Outer Layers of the Retina and of the Chorioid As the pigment epithelium as well as the neuroepithelium receives its nu- trition from the choriocapillaris of the chorioid, the appearance of pigment changes is the characteristic symptom of the ophthalmoscopic picture pro- duced by a disturbance in this vascular region. On account of the simul- taneous involvement of the retina and the chorioid we do not speak in these cases of a retinitis, but of a chorioretinitis. Although in rare cases a pig- mentation of the retina may take place as the result of a retinal hemorrhage, yet in the majority the following statement is correct: The appearance of pigment stains, and of abnormal accumuhition>t of pig- ment, in the retina indicates a disease of its outer lai/ers. or of the chorioid. a chorioretinitis: diseases of the retina uithout invohement of the pigment are, on the contrary, of its inner layers. The Position of tlie Cliaiiifcs in tlir lleliiin. i.e., the depth at which they lie, can be determined ophthalmoscopically : 1. From their relations to the retinal vessels. If the latter pass over the former the changes are deeper than the vessels and therefore ai'e in the deeper laj'ers of the retina (Fig. 31 )• If. on the contrary, the vessels are partly or wholly covered, the changes lie in the superficial layers (Fig. 33). Should the vessels be completely hidden, as by a hemorrhage, the change must be upon the retina, and the hemorrhage, in the example cited, is called preretinal. 114 2. From their form and arrangement. Sti'iatid putclies or liemorrhaf^es (Fig. 32), especially such as extend in the foi-iii of rays from the papilla, or accompany the larger vessels (see Fig. 28), He in the most superficial layers and follow in them the course of the nerve fibers. When tliey are irrefrular, or inclined to be round, they usually lie in the deeper layers (Fig. 35)- An exception to this rule is formed by the stellate patches in the macula seen in albuminuric retinitis (Fig. 34), which lie, in spite of their i-adiation, in the deeper layers of the retina. 3. From the presence or absence of anomalies of pigment. The presence of these shows that the changes lie, in part at least, in the deepest layers of the retina. Betiititis. The name retinitis is used to indicate things with which infiammation has nothing to do. A reform of ophthalmological nomenclature is greatly needed here. As soon as hemorrhages, or bright spots, or dark spots are visible in the fundus, the patient is said to have retinitis, no matter whether they are foci of inflammation, products of dei)-ener;ition, or the results jjroduced by altered vessels. To be sure, inflannnation and detruneration can scarcely bo discriminated in the ophthalmoscopic picture, and the pathological condi- tions that have been found in other similar cases must be taken into account in order to be able to determine the disease in any particular case. Usually that which is called retinitis, and is manifested in the form of diffuse, or cir- cumscribed bright spots, or of hemorrhages, is the result of diseases of the vessels. The extremely sensitive tissue of the retina, with its very small capillaries, reacts with great ease to any disturbance of circulation, and likewise any change in the composition of the blood or tissue juice leaves its trace in the retina. Often the very first signs of a general disease are made visible in the retina because it is so very sensitive. Unfortunately the manifestations in the eye of the various constitutional diseases are remarkably alike, so that it is only in rare cases that the exact etiological diagnosis can be made from the ophthalmoscopic picture alone, it usually has to be learned from the results of a general examination. Even though it is not always possible to make the etiological diagnosis from the ophthalmoscopic examination, yet this much can be learnid. tliiit a (jrii- crtil disease is present in oil cases in xehicli fresh changes arc found in the form of white or black spots, opacities, or hemorrhages. In such a case it is our imperative duty to submit the body to a very thorough examination, pay- ing particular attention to the urine. Are Alterations in the Pigment Epithelium Present or Not? The inner layers of the retina are nourished by the central artery, while the outer, together with the pigment epithelium, derive their nutriment from 115 the chorioid, us has been already pointed out. Disturbances in the central artery of the retina therefore are made manifest by chanjfes in the inner layers, those in the chorioid by changes in the outer layers and particularly in tlie pigment epitlielium. This is the reason why the question, whether alterations are present or not in the pigment epithelium, is of such great im- portance, for the answer to this question is decisive with regard to the seat of the disease and the vascular system that is affected. The alteration of the pigment epithelium may manifest itself in two ways, either as a depigmentation, i.e., an atrophy of tlie j)igiiient layer, or as an abnormal accumulation of pigment. Depigmentation lays bare the tissue of the chorioid and allows the chorioidal vessels, which are more or less changed in such cases, to be seen, when the sclera itself is not laid bare by the sim- ultaneous atrophy of the chorioid. This gives rise to white spots, which need to be differentiated from the white spots of the retina. For the differential diagnosis see page 125. C. Special Diagnosis We have made quite a digression into a rather theoretical field and will now return to the practical diagnosis. We liavc studied the papilla and its vicinity with tlie greatest care, wo have observed the retinal vessels from the various points of view, and now we turn to the diagnosis of the special diseases of the retina. We will be guided first by the question. Are Pigment Changes Present or \ot? and will deal first with Retinal Lesions Which Exhibit No Alterations in the Pigment Epithelium (Diseases of the inner la^'ers.) These are mainly Hemorrhages, White Spots, and Diffuse Opacities. These will guide us further. Naturally all three disturbances niaA* be present at the same time. Hemorrhages and wliite spots occur together very often. So, too, are diseases of the optic nerve often combined with these changes in the retina. Hence we will make the following subdivisions in order to proceed in the differential diagnosis: 116 /. Hemorrhages: («) As the onl/j, or the most importiint change in the retinii. perhaps in combination teith changes in the retinal vessels: {!)) in connection :dth diseases of the optic ner-ee and its r^icinil//. II. \\ liite spats uitli or uithout lictnorrliat/es or diseases of the oiitic nerve. III. Diffuse opacities. I. HEMORRHAGES (a) Hemorrhages as the Only, or the Most Important Change in the Retina. Aftor wliat has heuii said it may scxiii uiimctssarv to call attention to thu significance of hcniorrhaircs in the fundus, hut this definite statement may be repeated on account of tlic importance of the subject: 117((7( injuries, high myopia, and glaucoma can he excluded hemorrhages are alzca//s signs of a general disease. They form a siuiial of warniri"-; there is somethiiiii- out of order in the organism ; make a general examination. Even when the hemor- rhage is as sliglit as that to be seen in Fig. 20. it may and must be made the starting-point of the diagnosis of a serious dise.ise. After hemorrJiage.s have been found special questions arise cojtcerri' ing their size, abundance, and position. Hemori-hagcs may be of the most varied e.xtent ; sometimes we find little, circumscrii)ed })atches, which can be seen only after a very careful search with the pupil dilated, and in the upright image alone. The only advice that can be given the physician — and this implies no question as to his skill — is to dilate the pupils in a doubtful case in order to be able to make a more accu- rate examination. The only precautions to be observed are those given on page 11. On the other hand, the hemorrhages may be so massive as to form the most prominent feature of the ophthalmoscopic picture, as to cover every detail, and to make the fundus look like a single lake of blood (see Fig. 27). The number also of the hemorrhages may vary extremely. As regards the depth at which they are situated it has already been said that fine, striated hemorrhages which radiate from the papilla lie quite super- ficially in the layer of nerve fibers, while roundish, or lumpy ones are to be sought in the middle or deep layers. Hemorrhages that cover the retinal ves- sels lie in front of the retina and are called preretinal ; they are usually round, or oval, in form, and are found for the most part in the region of the macula. Topograj)hically the following points have to i)e noted: the position of the hemorrhages relative to the papilla, to the macula, and to the large vessels, whether they are diffusely distributed, and whether they are in the vitreous. 117 Small hemorrliagcs come from tlie capillaries, large ones fioiii tlic larger vessels. It is often impossible to differentiate between a venous and an arterial hemorrliaee, and the differentiation is of little use. When ditt'ei-eiues in color are to be seen they are to be ascribed to the different ages of the iieniori-hages, as fresh ones are of a bright, blood red, while old ones are of a dark, l)rown red. Note. The absorption of hemorrhages takes place pretty slowly as a rule. The spots gradually become darker, until they finally disappear witiiout leaving any traces, or tiiey become transformed Into wiiite sjiots, wliicli in turn become invisible; it is only in rare cases that masses of connective tissue and pigment remain as traces of a hemorrhage. On the other hand, hemor- rhages may last for months. The impairment of the functions of the retina depends on the situation, the force exerted at the time when tiiey occurred, and their size. An attack of glaucoma may be mentioned as one of the pos- sible consequences of a severe intraocular hemorrliage, but, inversely, glau- coma may also be the cause of iiemorrhage (see page 120). Is a Differential Diagnosis Possible, Based on These Findings? It is in many cases : 1. From the extent. If we find as extensive a hemorrhage as that shown in Fig. 27 we can confidently base upon it the diagnosis of thrombosis of the main trunk of the central vein. This clinical picture was named by V. Michel apoplexia sanguinea and compared by iiim with corresponding hemorrhages in the brain. When we study the details of the picture we are struck by the fact that we cannot actually see tlie vessels, except above and very close to the papilla. The veins are dark red, almost black, and tortuous in places, while the only visible artery is small and exhibits a strikingly dis- tinct reflex lijjht streak, which indicates a commencing sclerosis of the vessel wall. The papilla is still fairly visible in this case, but frequently it is in- volved in the area covered by the hemorrhage, wlien its margins are totally hidden. The thrombosis is a consequence of arteriosclerosis, or perhaps of syphilis, or of nephritis, and therefore its prognostic signification is grave (see page 153). •2. From the position. If the hemorrhages are not spread all over the fundus, but only occur along one or more vessels, as shown in Fig. 28, we may speak of a partial thrombosis, especially when tlie vessel itself shows alterations. The vascular changes could not be studied in the last picture on account of the enormous number of liemorrhagcs, but in this one they can be studied very well. The thrombosed vein is broadened on the wiiole, its caliber varies in different places, it is accompanied by abnormal reflexes, and is filled by a very dark, almost black, cohnnn of blood. The cause is arteriosclerosis, syphilis, or nephritis. 118 Isolated hemorrhages in the niiU-iiln are usually <>f an arteriosclerotic nature when a high degret' of myopia is not present, ami an injury can l)e excluded. 3. From the form. Little shuttlelike hemorrhages, each with a white spot in its center, are connnonly caused by such diseases of the blood as anaemia and leucocythaMnia. No definite etiological conclusion can be drawn in any other case from the condition of the hemorrhage. In all other cases the result of the general examination must be awaited. Such an examination must be made in those cases that have been mentioned as well, because the arteriosclerosis that may exist may be complicated by other diseases. The causes of a retinal hemor- rhage are very many. The Causes of a Retinal Hemorrhage The first cause to be mentioned is an injury. It is by no means neces- sary that the eyeball itself shall be wounded, hemorrhages result from con- tusions, and are particularly common when the eye has been struck by a ball. In these latter cases special attention should be paid to the macula in the examination. They are also found after severe injuries of the body, such as compres- sions of the thorax. They may appear congenitally as the result of trau- matism during labor. More rarely they are to be seen as the result of the penetration of a foreign body into the eye, as shown in Fig. 29. Emphasis is to be laid on the word "seen" in this connection, as they are often present though invisible because of the hemorrhage that takes place into the vitreous at the same time. Their most important cause is arteriosclerosis, and in these cases they are of very great prognostic value because, in at least .507c, they are forerunners of hemorrhage into the brain (see page 153). These hemor- rhages have been studied already under the forms of total and partial throm- bosis of the central vein, and of the isolated hemorrhage in the macula, but they are also found distributed about in the retina as diffuse spots, which give a very bad prognosis with regard to the later onset of apoplexy, from 80 to lOO'/c, while a thrombosis is followed by apoplexy in only about 50/i . Finally, it may be mentioned, for the sake of completeness, that arterioscle- rosis may manifest itself through a hemorrhage into the vitreous. Reference is to be made to the chapter on "The Changes in the Vessels of the Retina," and the very careful study of these vessels is urged upon the reader. Diabetes and nephritis, especiaUy tke form of the latter characterized by the granular atrophy of the kidney, are very important causes both of little, stippled hemorrhages, and of 'large, lakelike ones ; both forms usually appear at the same time with white spots, or disease of the optic nerve, so 119 the description of them is reserved for a later cliapter. This etiology is always to be borne in mind when the hemorrhages are isolated. Syphilis is likewise one of the principal causes of retinal hemorrhages, but other manifestations of the disease are usually present. All of the remaining causes are much less frequent. First among tluin come tlie diseases of the blood. It has already been said tiiat these hemorrhages often present a special form, a spindle, or shuttle shape with a white spot in the center, yet they may not have this peculiarity, but may appear simply as small spots and stripes. Hemorrhages are rarely met with in chlorosis, they are more common in pernicious ana'mia, and occur most often in leucocytha-mia, chiefly in the form of stri.-e. In well marked cases of the last mentioned disease the orange tone of the fundus and the great breadth of the vessels arc diagnostic. Similar hemorrhages are also observed in simple an- case whether a certain white spot in the fundus is in the retina or in the chorioid. The reason why is apparent wlien we consider that in many cases, as in the case of miliary tuberculosis pictured in Fig. 81, we do not see the chorioidal affection itself, but have to be satisfied with the observation of the secondary symptoms which are produced b}' a lesion in the chorioid upon the retina that lies over it, for example, of a circum- scribed oedema. Still, in spite of the fact that we can see onh' the secondary symptoms in the retina, we can make the diagnosis of tubercle of the chori- oid in this case, because our clinical and pathological experience is that under certain conditions of high fever and stupor the appearsuice of circum- scribed patches of I'etinal (rdema in tile fiuidus are inilicative of tubercle of the chorioid. We nmst be guided many times in this way by our general clinical and pathological experience in deciding whether the lesion is in the retina, or in the chorioid, but this may fail if we do not use at the same time our special ophthalmological knowledge. Spots may appear in sepsis, and therefore be attended by quite similar general symptoms, which may seem very like those of miliary tuberculosis, but they are situated in tjie retina, as has been proven by pathological examination. Hence the general symptoms may guide us wrongly in these cases if we do not know that hemor- rhages occur far more often in septic retinitis than in miliary tuberculosis, while on the other hand, a simultaneous involvement of the optic nerve points rather to the latter. I do not wish to make a cai-cful observer timid, or to stump a young ophthalmologist with such an unsatisfactory case, but only to show him by this example that the answer to the question xchethcr the lesion is in the eho- rioid or in the retina, is not to he learned through the vision alone: it is to he ohtained only from the most careful consideration of the other conditions in the eye and the utilization of genercd clinical and pathological knozcledge. A number of SA-mptoms can always be found whicii will make the diagnosis certain in one way or another in any given case. When we sec, for example, in Fig. 38, that the white spot lies partially over a vessel in the retina, we know positively that the lesion is retinal, and when, on the other hand, we see in Fig. 74 that the patch is surrounded by a beautiful wreath of pigment, we need nothing more to prove that the disease is of the chorioid. Unfor- tunately these positive signs are not always present ; in Fig. 31 the vessels \26 of tlio iTtina run over the vhite spots, and in Fio-. 81 tlic wliite s])()ts have no [jignientcd borders, yet in the one tlic lesion is in the retina, and in the other ill the cliorioid. Therefore we lia\e to ditl'erentiate hetween tiiose symp- toms that are trust wortiiv, or nearly so, and those that are adjuvant. Differentiation hettreen Lesions in tlie Cliorioid (ind the Retina. 1. Trusixcortliii sijmptoms. These can he accepted only in sense, i.e., their absence does not prove thi' contrary. Ncti/itil Lesion Chorioidal Lesion 1. The partial covering of a leti- nal vessel by a white spot ( Fit;-. 38 ) ■ 2. A stellate form in the macula (Fi-. 34). |>ositivc 1. Pigment deposited about or on the sjwt (Fig. 71). 2. The demonstration of chori- oidal vessels, whether sclerosed or not, in the spot (Fig. 64). .3. A markedly cresccntic form, as in Fig. 83. 3. The demonstration of liemor- rhages in the retina, and of changes in the retinal vessels is relatively cer- tain (Fig. 35). N. B. — If both varieties of spots are found in any case, changes are probably present in both membranes; thus, in Fig. 50, the retinal vessels are partly covered by the spot, and yet there are heaps of pigment at its upper margin. In this case there was a fresh disease of the retina, glioma, and an older disease of the chorioitl, perhaps due to hereditary syphilis. 2. Adjurinit St/mptoms: Uctinal Lesion Chorioidal Lesion Bright, often brilliant white. Fresh: yellowish, reddish yel- Color: more rarely yellowish or low, slightly gray. Old: reddish. Edematous spots white, but with pigment, gray. formed by of smaller Size: Position : Visibility of the vessels of the cho- rioid : Usually small, or the confluence spots. A'ariable. A large white patch below (in the invert- ed image above) the optic nerve indicates a coloboma of the chorioid. Very rarely in the periphery. Often in the j)eriphery. In the case of a tesselated or In the case of a uniform, albinotic fundus the vessels of the chorioid are usually invisible in the vicinity of the change in the retina because of the opacity of the elsewhere transparent membrane (Fig. 22). stippled fundus the vessels of the chorioid stand forth and indicate early changes in that membrane. Notice the partially albinotic fun- dus in Fig. 57. 127 In spite of all this hulp there remains quite a number of cases in which the diagnosis may be doubtful, and it is necessary that wc should be acquainted with these in order to avoid falling into error. (a) Changes in ihc Hi-thui. 1. The coronnhi, in a case in which a total occlusion of the central artery took place at some former time. A number of fine bright, yellow or reddish spots are to be seen arranged in a circle in the macula, and are usuilly surrounded by a slight pigmentation (Fig. 16)- The coi-rect diagnosis i; indicated by the atrophy of the optic nerve and the extreme smallness of the retinal arteries. (b) Changes in the Chorioid. 1. Aside from this circular arrangement, arteriosclerotic changes in the macula (Fig. 62) may form an ophthalmoscopic picture which is quite similar to that presented by the corcnula. The results of the general examination, the other arteriosclerotic changes in the eye, and the age, must all be taken into account in making the diagnosis. These changes arc due to a circum- scribed Jiyaline degeneration of the choriocapillaris. 2. Colloid Formations on the Vitreous Lamella (Fig. 41). These appear as little, bright points, of a yellowish, or yellowish gray color, which can be differentiated from the typical spots in the retina by their color and by the indistinctness of their outlines. Pathologically, they are small, knoblike thick- enings of the vitreous lamella of the chorioid, which mechanic;dly destroy the pigment epithelium at the places where they exist. But, as this leads in turn to accunudations of pigment, little black lumps can generally be seen in their vicinity. 3. Little Foci in Sympathetic Inflammation (Fig. 40). Little sharply defined spots, whitish, yellowish white, or reddish yellow in color, are to be seen sometimes in the periphery of the fundus of an eye that is sympathet- ically inflamed. They are usually round, more rarelv oval, and have little tendency to blend. Sometimes there is a brownish tesselation in their vicinity? although a true pigmented edge, or a marked accumulation of pigment, is absent. For this reason, which indicates a retinal affection, some authors believe these spots to belong in fact to the retina, but we must look upon them as appertaining to the chorioid because of the nature of the disease as a whole, and because of the anomalies of pigment occasionallv to be ob- served. When other symptoms of sympathetic intlannnation are jiresent at the same time the diagnosis cannot fail to be made. N. B. — Attention must be called to a possibility of error that arises from mistaking reflections from the retina for pathological changes. These may appear just like little yi'llowisli patches in the macula, but thev disappear when the pupil is dilated and the examination is made by the direct method. They also change their forms when the mirror is rotated. After the diagnosis of a disease of the retina has been established in the above manner there arises 128 Question 2 Is This a Case of Medullated Nerve Fibers or Not? Mc'dulliiti'd nerve fibers occupy ii unique position anion^ the .iffVctions of the retina, so it seems best to deal with them separately. The entire nature of tlie condition is expressed by the term nuchiMatrd nerve til)ers, wiiilc all other white spots in the retina are only symptomatic of causes that must be ascertained through other conditions. DiagnoKis and Imporlaiirc of Mfdullaii'd Nei've Fibers. Medullated nerve fibers (Fig. 9) are quite superficial, in hai-niony with their anatomical development, and thus partly cover the vessels of the retina. They radiate from the papilla and show a more or less distinct fii)rillati(in, corresponding to the course and the construction of the fibers, which is particularly evident at the margins of the patches that they form, where they often terminate in a fiamelike figure. They are for the most j)art slightly yellowish in color, and connnonly are in immediate connection with the papilla, though occasionally separated from it, when they follow the course of the large vessels. The diagnosis is somewhat more difficult in the latter cases, but the difficulty is removed by observation of the markings of the fibers and, above all, by the absence of any other lesion. The great stress that is to be laid on the latter condition is shown by the lesion pictured in Fig. 32,' which agrees throughout with the description given of medullated nerve fibers, although it rarely happens that such fibers overlap the entire margin of the papilla, but is proved not to be such by the little hemorrhages at the margin of the lesion. Medulhited nerve fibers foi-m a congenital anomaly and are therefore of no other clinical importance. After these lia\e been excliidid conies Question 3 Of What Nature Are the Spots in the Retina? This question must lie divided into two: 1, with regard to the pathology; 2, with regard to tiie etiology of the spots. The spots may differ greatly ill their pathological construction, and yet arise from the same causes, or, on the other hand, they may be due to quite different causes and present the same pathological picture. 129 Question I/. In how far can the Pathological Construction of a Spot be Deter- mined from the Ophthalmoscopic Picture? Differential Dtugnosis of White Spots from a I'atIii)lo(/iriiJ Standjioiin Leaving mcdullatud iktvl' fibers out of consideration, white spots may be due to connective tissue, to proliferation of the glia, to varicose thickening of the layer of nerve fibers, to fatty degeneration, to wdema, to fibrinous or serous exudates, to deposits of calcareous matter, or to hyaline degeneration. 1. Connective Tissue (Figs. 36 and 37)- — The presence of connective tis- sue always indicates that a serious disturbance has taken place in the retina, except in the rare cases in which it is present congenitally. In the majority of cases it starts from the vessels, or from their adventitial sheaths, and consequently is almost always seen in connection with vessels that are either pathologicalh' changed or newly formed. These are cases of retinitis pro- liferans. The development of connective tissue is caused by hemorrhages, or, in a small number of cases, by lacerations of the chorioid and retina. Tliese naturally present no typical arrangement (Fig. 82). The color is like that of medullated nerve fibers, except that it is rather duller, and thev often have a similar striated structure. Usually it can be determined by parallactic displacement that they project above the level of the retina. Aside from the tilings already mentioned, arteriosclerosis plays the most important part in tiieir etiology, then comes syphilis, and, in the third place, diabetes. In the latter disease the masses of connective tissue are particularly well marked and project far into the vitreous, as in Fig. 36. 2. (Edema. — Only those cases in which the a?dema is circumscribed are included here; those in which it is diffuse, as it usually is, do not enter into the question (for these see page 149). The diagnosis is particularly difficult when wdema occurs at the same time with other affections of the retina, but its presence may be suspected in every serious retinal disease. The diagnosis is easy only when it occurs in isolated patches. It is then usuallv found over fresh choriorctinitic lesions, especially tubercle nodules, wiien it manifests itself in the form of medium-sized, roundish spots of a light gray color, with obliterated margins and a distinct elevation, wiiich can be determined particularly well when retinal vessels pass over it (Fig- 78). Although only the oedema of the retina is to be seen in such cases we are accustomed to make from it tlie diagnosis of a lesion in tlie chorioid. 3. The varicose thickening of tlie lai/er of nerve fibers has the same sub- stratum as the medullated nerve fibers and often resembles the latter very 130 closely. The altcnd fibers are of i\ light, golden wliite, have a certain liril- liancv in places, and radiate in striie from tlie papilla. This chantre is met with in tile greatest variety of diseases, as a local piienomenon of neiii'o- retinitis of albuminuric and other origin, in choked disk, in diseases of the vessels, and so on. It often covers or envelops the vessels of the retina as it is quite superficial in its situation (Fig. 32). 4. Fdttt) Degeneration. — This is certainly the principal cause of the whit" spots. To it are to be ascribed the white spots ordinarily to- be seen in albuminuric retinitis. They appear ophthalmoscopicaliy as yellowisii, or pure white (Figs. 30 !ind 31)) small, roundish patches which often blend, and so produce large spots. They lie mainly in the intei-granular layer and have a special predilection for Mueller's supporting fibt'rs. The vessels of the retina may be seen to glide over these patches. The granules of fat are also to be found iti the layer of nerve fibers, the layer of ganglion cells, and the internal granular la^-er, but to a much less degree; they are never present in the layer of yisual cells, or in the outer granular layer, which have a different nutritive supply (see page 113). The stellate figure in the macula is brought about by the fatty degenera- tion of the supjjorting fibers, or, according to others, of Henle's layer. This fattj' degeneration is met with in all manner of diseases, but chicfiy in nephritis and diabetes. 5. Fibrinous exudates may lie in any or the inner layers of the retina and consequently may be in various relations to the blood vessels. The spots thus produced are larger than those caused by fatty degeneration, and some- times they induce a slight elevation of the ])art affected (Figs. 38 and 39). When they are superficial they are of a light blue white color and look as if they ^vere loosened up, like bits of cotton. N. B. — Sometimes little glittering points or needles can be seen in the retina. These are crystals of cholesterin, such as are to l;e seen sometimes floating in the vitreous. When tlie latter are situated in the most posterior layers of the vitreous they may perhaps simulate s])ots in the retina, but their great parallactic displacement, and the fact that they can be seen when we simply throw light into the eye, prove them to be what they are, the so-called synchisis scintillans. None of the otiier pathological changes mentioned above can be recog- nized with certainty from the ophthalmoscopic picture. The Course of the changes that have been mentioned is usually very slow. In mild cases the symptoms undergo involution after some weeks and the eye may return to its normal condition, both functionally and ophthalmoscopicaliy. The little white spots caused by fatty degeneration gradually become redder, ill defined, and tin n blend with their surroundings. Fresh spots are therefore bright white and nIku ply defined, while older ones are reddish and ill defined. 1.31 A prolonged duration of tlic distiisc finally injures the nervous elements moi-e or less, so that at least an impairment of the functions remains, and in many cases changes are left that can he seen with the opht h;ihiic)--ciipi', such as a migration of j)igment into the atrophic retina, changes in the vessels, and atrophy of the optic nerve. In other cases atrophy of the papilla results from atroj)hy of the nerve fibers. A case is pictured in Fig. 16 in which a destruction of the nerve fibers, and, as a result, an atrophy of the optic papilla, was caused by an occlusion of the central artery. Pigment cells have migrated into the atrophic retina around the papilla and in the region of the macula. In other cases the change may be located very near the papilla, as in Figs. 32 and 33, when the consequently atrophied disk will probably show very indistinct margins. In still other cases such a picture may finally be produced by the increase of the changes, as that shown in Fig. 34. Sometimes bands of connective tissue may be seen to appear together with the advancing atrophy of the retina, as in Fig. 36- A description of these that is generally applicable cannot be given. Question 5 In how far can a Conclusion be Drawn from the Ophthalmoscopic Picture Concerning the Etiology of White Spots? Differential Diagnosis of White Spots from the Etiological Standpoint As the etiology of the white spots may vary greatly, and as, on the other hand, the cause of the spots cannot be ascertained in this way alone, the final decision as to the etiology must be left to the results of a general examination. It must always be borne clearly in mind that the eye is not an organ standing alone by itself, but that it is a part of the entire body, and that, with few exceptions, the diseases of the fundus arc simply symp- toms of general diseases. It is as true of white spots as it is of hemorrhages that they are signals of warning to show us that danger threatens. The retina, with its very complicated structure and its highly developed func- tions, is a specially fine reagent to a great many disturbances of the general organism. Our duty is therefore imperative, just as it is in cases of hemorrhage into the retina, to make a thorough examination of the bod?/, particularli/ of the urin£ and of the blood. If nothing is found on the first examination, some- tliing may be detected on the second, for the change in the retina precedes the other symptoms in many cases, but it is rarely misleading. Von Michel frequently told of a case in which he made the diagnosis of albuminuric retinitis, although the family physician could discover no albumin in the urine in spite of repeated examinations; it was not until after the urine had been precipitated that some granular casts were found, and yet V.V2 tlie patient died two years later with tlie syiiiptonis referalili^ to a eoil- tracted kidney. What was said above, tliat in tlie determination of the etiology of a disease of tlie retina reliance must be placed exclusively on the results of the general examination, must not be taken literally, for I he expert can certainly make the etiological diagnosis in many cases from the oplithalinoscopic picture — provided that the change in the retina is typical. This is, unfortunatel}', not always the case, so the statement generally holds good, even for the expert. VVe will now try to ascertain what characteristics are jieculiar to the '^dividual forms, but it must be stated again that, of the wiiole number of changes described, none may perhaps be present, except one or two minute white s[)()ts, or a small hemorrhage. We will first di\ ide the cases, according to an outward clinical symptom, into (a) Bedridden, Febrile Patients (Retinitis Septica) The internist knows that typhoid fever, miliary tuberculosis, tuberculous meningitis, and sepsis can be dittereiitiated with the ophthalmoscope. T.et us suppose that we have been called into consultation over such a patient, who has high fever and no characteristic symptoms. What is to be expected from us.-* In sejisis we find in the fundus near the papilla, never in or near the macula, mediuni-si/ed, roundish, or oval white spots, and similar hemor- rhages, but they do not lie regularly in the vicinity of the vessels, as in thrombosis. In many cases the hemorrhages are very large and extensive, often so as to cover the blood vessels. In typhoid fever wo never find such white spots and rarely luinorrhages. It is self-evident that these may sometimes be absent in sepsis, so it is only the positive condition that is diagnostic. In tuberculous meningitis we generally find an optic neuritis, like that shown in Fig. 81- In niiliai-y tubi-rculosis, on the contrary, we find yt'llowish, or yellowish gray spots, as rejireseiited in the same picture, and as they have been de- scribed under tubercle of the chorioid (page 180). The picture was taken from a case of miliai'v tuberculosis which j)rovetl on autopsy to be also one of a severe meningitis. The importance of ophthalmoscopy in the difll'erential diagnosis of the above diseases has been decreased a good deal by the introduction of such specific reactions as that to tuberculin and Wiihil's. 1:53 (b) Nonfebrile Patients 1. Retinitis cilhnminuricn. This comes first in importance. The beautiful picture of the stellate pgure in the Jiuieula (Fig. 34) is so impressed on the minds of most students that iliet/ expect to find it in everi) case of tliis disease, and ijet it is met xcith only exceptionalli/; ordinarUi) ice sec onlij single u-hite spots of the form and size depicted in Fig. 31. Tile characteristic signs of an albuminuric retinitis are as follows: (a) Signs on or about the papilla, such as an optic neuritis with a large or a small white r'uiij; (Figs. 32 and 33). but these may be absolutely absent, as in Figs. 30 ami 31. {/^) Hemorrhages, both striated (Fig. 32) and punctate (Fig. 31)- These likewise may be lacking in any given case (Fig. 30)- (y) Little white spots in and about the macula (Figs. 30 and 31 )• These also may not be present. (5) The stellate figure in the macula (Figs. 30 and 34), but this is by no means always present and it may be met with in other diseases. These pictures are shown for the purpose of demonstrating that those things which give the characteristic appearance to one picture may be com- pletely absent in another, and that the same cause may give rise to the most diverse pictures. An idea of the protean character of this disease can be obtained by combining the different forms, strengthening (Fig. 34) or weak- ening the individual factors. There are other signs in addition to those that have been mentioned, but they are of less diagnostic importance. (t) Changes in the blood vessels, in the form of accompanying stripes (Fig. 33). interruptions of the column of blood, and spindle-shaped pouch- ings (Fig. 34). (C) Detachments of the retina (Fig. 33)- ('/) Changes in the vessels of the chorioid (Fig. 69)- (6) Increase of the signs on the papilla to such a degree that it is difficult to differentiate it from a choked disk with patches of degeneration (Fig. 20). The diagnosis is finally made from the general condition (see page 82). It still remains for us to consider the details of these signs, referring to the various pictures and the accompanying text. There is one point that needs to be brought out again, the behavior of the vessels in albuminuric retinitis ; the arteries are much underfilled, while the veins, on the contrai-}-, are distended. A choked disk may be simulated very readily b}' an increase of the symptoms in the optic nerve, especially when there is at the same time an cedema of its luatl, the more so as choked disk sometimes occurs together with these patches of degeneration in the retina. r\ Michel used to say humorously that he knew a certain high oflicial to be a smart fellow. 134 because lu' li:ul in.'uic a tiimlv I'fcoiriiitioii of the alhiiiniiiuric cliaractLT of an optic neuritis that Irul liccn mistaken elsewhere for a choked disk. AH of the forms which were mentioned in the description of tlie patliohigy of the white spots are to he found in the picture of alhuniinuric ri'tiiiitis. We see the deg-eneration of the niTve fibers in l''ig. 32, the fatty (U'dcma, it is not tlif only one. 'riii^ affictions of tlii' optic iutvl", due to diseases of tlie ear, are verv imi)ortant (see page 77). In these cases tlie oedema may precede the changes in the optic nerve, and may he at times tl»e only symptom present. It seems to lie in the deeper layers of the retina, as striations are almost never seen. It inav also he ohserved in choked disk, especially in the alhuiiiiniiric va- riety, hut hemorrhages and white spots are seldom wanting in such cases. 2. Another, very much rarer, form of diffuse o])acity of the retina is the diffuse infiltration with white blood corpuscles, an outspoken inflammation. This is characterized hy the very marked sheathing of the vessels of the retina shown in Fig. 42, which is to be ascribed to a distention of the adventitial sheaths of the vessels with white blood corpuscles. This form is likewise met with in syphilis, and sometimes in leucocythaMiiia. Considerable accumula- tions of leucocytes in circumscribed places make themselves evident as white spots. 3. A necrosis of the inner layers of the retina in connection with recur- rent oedema (Figs. 44 and 45) underlies the opacity of the retina in occlu- sion of the centred arteri/. In these cases the demonstration of the cherry red spot (see also page 72), which is sometimes surrounded by a particu- larly cloudy halo, hut usually lies in its opaejue surroundings without such a special border, is of diagnostic value. The opacity itself is brighter in these cases than it is in purely infiannnatory oedema, and sometimes it is perfectly white. The arteries are usually, though by no means always, invisible, or considerably diminished in size. The eroded place in the vessel itself can be seen in many cases as a w-hite spot, as in Fig. 45 on the papilla. Pulsation is absent when pressure is made on the eyeball (see page 107). The opacity gradually retrogresses (compare Fig. 45 with Fig. 44) until finally the normal color of the fundus returns, with a uniform whiteness of the papilla and an extreme contraction of the arteries, but intermixed with a gentle dark gray tone, due to a migration of pigment cells into the atrophic retina ( Fig. 16). This migration of pigment is particularly distinct in the region of the macula, where it takes part in the formation of the coronula (see page 127). The occlusion sets in with sudden amaurosis, which commonly is irre- parable. Sometimes it is not the entire trunk of the artery that becomes occluded, but one or more of its branches (see Fig. 38, P'lying "o attention to the white spots). Then the amaurosis is not total, but affects only certain por- tions of the field of vision. It also may happen that the trunk of the artery is occluded behind the point where certain branches are given off. The region supplied by these branches is then seen to be of a normal red color, while the rest of the retina is opaque. The vision appertaining to this place is j)reserved. 4. The opacity in cases of conmiotio retina' (Fig. 43) if^ to be looked 151 upon as due to x-asomotor disturlxincc -idfh transudation. The opacity may- have a close resemblance to the one just described. It is usu.iily i'ounil near the macula or the papilla. The condition of the vessels, which are normal or dilated, and the other signs of traumatism frequently to he observed, such as hemorrhages and ruptures of the chorioid, taken together with the his- tory, generally enable a ditt'erential diagnosis to be made from other forms of opacity. Usually the vision is harmed little if at all. The transudate j)asses away in a few days. 5. Another cause of a diffuse opacity is the flat dctachnu-nt of the retina (Fig. 46). The wt)rd "Hat" must be emphasized in this c(mnection, because the chief and most striking symptom in the eye when the detachment is gib- bous is the difference in level. The color of the detached portion is gray, sometimes gray green or gray blue. The detachment may be total (Fig. 46). '>r ])arti.d (Fig. 47). P'lr- ticular attention is to be paid in the differential diagnosis to the white cords, in the vicinity of which the vessels of the retina often show abnormal bends. These are the apices of the folds formed in the retina. A very valuable symj)tom is the absence of the markings of the chorioid in the detached portion, which are visible elsewhere. The vessels of the retina throughout the same area are vei-y dark and have no reflex. The local elevation of tlie retina may frequently be perceived by parallactic displacement and by determination of the refraction. In cases of total detachment of the retina the loss of vision is very great; when the detachment is partial the loss is greater or less, according to the position it occupies. The field of vision usually exhibits a contraction that corresponds to the detached part. Ordinarily the detachment begins in the upper part of the retina and causes a defect in the lower part of the field of vision, so that when the pa- tient looks at a person the latter may seem to have no legs ; later it moves downward and causes a defect in the upper part of the field, so that the per- son looked at may seem to have no head. When a detachment connnences the patients complain of siihjective sensa- tions of light, the so-called photopsias, which are described as scintillations, flashes, balls of fire, sparks, or circles. Objects also appear to be distorted, bent, or jagged ( metamorphojisia), and sometimes they seem to be of a pro- nounced green. The detachetl places are blind to blue, i.e., blue is perceived by them as green or gray, and the patients suffer from hcmeralopia, .i.e., their vision becomes disproportionately bad as the light is reduced. The etiology varies. It may be 1, purely ocular, or local, as when the detachment is caused by an injury, either a perforating wound, or a contusion, hemorrhages, tumors, or a high degree of myopia ; 2, general, as when due to nephritis, arteriosclerosis, or syphilis. In many cases the diagnosis of these diseases as the cause can be determined from 152 other ocular signs, as from sck'roscd vessels, whiti.' spots, or black spots, but in others the differentiation must be made by means of a general examination. Ai'tcriosclerosis is the etiological factor in l-'ig. 47, as sliown by the sclerotic vessels in the vicinity of the pajiilla. (b) Diffuse Opuiitii of the UctiiKi xdtli Mdrkcd D'ltfcrcncca of Level. A difference of level is indicated wliiii some parts of tiie fundus are plainly visible during an ophthalmoscopic exaiiiinatii)n, while others arc indistinct. Detachment of the retina shares this symptom with quite a number of other diseases, sucii as a great amount of (I'deiiia, and opacities in the vitreous, but it is cliaracteristic of detachiiunt of I lie lutina wluii it disappears as soon as the observer makers his examination from a greater distance than usual, and the portions that were indistinct become clear, while those which were clear at first become indistinct. The reason of this phenomenon is that the detached portions of the retina lie farther forward than the rest and conse(|uently have a different refraction. In most cases the diagnosis of a detachment of the retina can be made more conveniently by simply casting light into the eye with the mirror of the ophthalmoscope than by an examination of either the inverted, or the upright image, as the detached portions then look much less red than the others. When the detached retina lies very far forward it may sometimes be seen by oblifjue illumination. Figures 48 and 49 therefore do not give pictures tliat are true to nature of a detachment of the retina, they are, rather, composite pictures which assume the ciianges to be made in the position of the examiner. Figures 48. 49. and 50 exhibit types of such a detachment. 1. Fig. 48 shows a (jibbous detaehment caused hi/ an exudate. The arch- ing of the retina can be seen, in addition to its changed color and the forma- tion of folds. The papilla has a slight haziness, which might perhaps cause it to be mistaken for an optic neuritis (see page 72). A distinct movement of the bulla back and forth ma}- be seen during movements of the eye. 2. Fig. 49 shows, in contrast to the above, a detachment of the retina caused hi/ a tumor of the chorioid. Its margins are sharply defined. No movement can be detected; on the contrary, the detacjiment gives the impres- sion of a solid, firm mass, which is increased by the fact that a reddish shim- mering from the tumor beneath the detached retina can be seen in certain places. The difference is not so distinct as it is in these pictures in many cases, and then the differential diagnosis is best undertaken with the aid of Hert- zell's lamp, which, when introduced into the mouth, transilluminates the globe from behind. A dark spot is to be seen when a tumor is present, while a serous eirusion allows the light to pass through freely. This method is par- ticularly useful when tumors are situated in the posterior segment of the eye- 153 ball, while for those in the antei-ior seginent better service is obtained from Sach's lamp, wiiich transilluniiiiiites the eyeball laterally. 3. Fig. 50 shows a gliamu of the retina. Tlie diagnosis rests chiefly on the facts that an embedding of the vessels of tiie retina can be seen in the tumor, and that the patient is young. In a total, funnel-shaped detachment of tlic retina no picture of tlie fundus can be obtained, as can readily lie understood if we look at P'ig. R. If the lens is transparent the detached retina can often be seen by ol)ii(iue illumina- tion, and the rounded protrusion can sometimes be seen by simj)ly throwinti; light into the eye with tlie mirror of the ophthalmoscope, but when these means fail a conclusion as to the condition of tlie retina can bo drawn from the pro- jection, as a large hemorrhage into the vitreous may pro- duce a similar picture. Loss, or limitation of the projec- tion is indicative of detachment, correct projection of a y.^^ j^ hemorrhage. Concerning the Prognosis as to Life of Diseases of the Retina and Chorioid Geiss lias drawn conclusions, of which the following is an abstract. I Arteries of the Retina. 1. Marked Arteriosclerosis oi the Retinal Vessels. All of the patients observed, to the number of IT. ranging in age from 40 to 7() years, suffered from an attack of apoplexy within 4 years at the most. 2. Sudden Occlusion of the Central Arter//. (a) Seventeen patients, between 40 and 70 years of age. with arterio- sclerosis, but without heart elisease. Of these 14 had an attack of apoplexy within 2 years, the other 3 died from arteriosclerosis in from 1 l/o to 7 years. (b) Si:: patients, between 40 and 70 years of age. with heart disease. One died of apoplexy 3 years later, 4 from heart disease within 2 or 3 years, and one was still alive at the end of 4 years. (c) Nine patients, 39 years or less of age, with heart disease. Prog- nosis not so liad. 3. Syphilitic diseases of the retina do not have the same bad prognosis as arteriosclerotic changes. II. Veins of the Retina. Thrombosis of tlie veins of the retina has not the bad prognosis of the dis- eases of the arteries. It is a purely local disease in .50% of the cases, and in only 50% is a forerunner of a sclerosis of the cerebral vessels, wiiich may not make itself manifest until a long time afterward. III. Vessels of the Chorioid. No coiu-lusioiis ;i.s to tile coiulitioii of tlic vessels in the brain can he drawn from sclerosis of those in the chorioid. I\ . Retinal Hemorrhages in arteriosclerosis, diabetes, and chronic ne[)hritis are, as a rule, harbinfrcrs of hemorrhages into the brain, which yet may not occur until after the lapse of years. Hemorrhag'es into the vitreous in young persons, isolated hemorrhages in the macula, and the retinal hemorrhages caused by syphilis do not partake of this bad j)rognosis. V. Retinitis Albuminurica. Of .'{« patiints, '2!) died within 1 year: -i died in from 1 to 2 years; 2 died in from 2 to 4^ yeai's. Three jiatients with retinitis albuminurica gravidarum recovered. VI. Retinitis Diabetica. Diabetic retinitis has a different prognosis from the isolated hemorrhages in the retina met with in diabetes, which are to be considered as precursors of cerebral apoplexy. Apoplexy supervened in only ^ of the cases. Half of the patients died within 2 or 3 years. PLATE XXIII Fig. 42. Retinitis Luetica Fig. 43. Commotio Retinae, or Berlin's Opacity Fig. 42. Retinitis Luetica (Sec pago 150) Primary sypliilitic retinitis, wlieii not a local plicnomenon of a ncuro- rctiiiitis, is a fairly rare disease in comparison with the secondary syphilitic diseases of the retina due to an atteetion of the capillaries of the choiioid. In the case presented here the papilla is comparatively little involved; its color is almost normal, its margins are fairly distinct, Init the vessels that lie upon "it exhibit a distinct obscuration and sheathing. The retina, on the contrary, is cloudy over a large extent, and only a few of the vessels of the chorioid can be seen through the opacity. The vessels of the retina look ha/y throughout the entire extent of the opacity and are y)artly sheathed everywhere. \o hemorrhages are visible; only a few, striated, wiiitish spots can be seen. In a similar case, which was studied pathologically by Buck, partial and circular inflammations of the adventitia and intima, together with obliterations of the capillaries, were found to he tlie cause of the trouble. Fig. 43. Commotio Retinae, or Berlin's Opacity (See page l.jO) This opacity received its name not from the city, but from the ophthal- mologist Berlin, who was the first to describe the condition, and to differ- entiate it froin detachment of the retina. The condition depicted here was produced by the blow of a ball against the eye of a boy 12 years old: tiie picture was taken a few hours after the injury. The papilla is much reddened, its margins are slightly hazy, enough so as to.be suggestive of a commencing optic neuritis, but the vessels, especially the veins, are normal. A light gray ring, with a rather darker center, can be seen in the region of the niacida. Such a lesion can be mistaken for a connnencing detachment of the retina when the vessels do not run smoothly over it and there is any sign of a fold. The changes, which caused only a slight impairment of the vision, disappeared completely after a few days (.sec page 72). The color of the opacity may be more intense than it is in this case, it may incline more to yellow, or to white, and it need not be situated exactly in the region of the macula. The nature of this change has not ^et been learned. 156 Tab. 23. Fig. 42. Fig. 43. PLATE XXIV Fig. 44. Sudden Total Occlusion of the Central Artery, the So-called Embolism Fig. 45. Occlusion of the Central Artery in a Later Stage Fig. 44. Sudden Total Occlusion of the Central Artery, the So-called Embolism (See l)ayt' 150) Occlusion is caused by n true einhoius only in extremely rare cases, and is usually due to a slowly developincr, hut sudtlenly becoming total, closure of the lumen of the artery by a proliferation of the intima, endarteritis pro- liferans. The papilla is very red, its margins completely hidden, the arteries can scarcely lie seen. A large area of the fundus, about 6 V. D. across and including both the papilla and the macula, is whitish gray and opaque. The well-known cherry red spot can be seen in the macula. In this case it is surrounded by a white areola (see pages 72 and 119), but this is not alwa^fs present. The white color of the fundus is the consequence of a rapid necrosis of the cerebral layer, which receives its nutrition through the central artery, in combination with an oedema. The red spot is brought out by the fact that the cerebral la3'er is absent at the fovea, so that the cedematous tissue is wanting and the dark color of the fovea stands out in marked contrast to its surroundings. The arteries gradually refill through the mediation of Zinn's arterial plexus (sec page 168), and the minute branches in the vicinity of the macula become strikingly prominent (Fig. 45). but the retina remains incapable of performing its functions and the papilla atrophies (see Fig. 16) • Fig. 45. Occlusion of the Central Artery in a Later Stage The margins of the papilla have become in part sharply defined again, its redness has passed away. The arteries have become refilled. The oblit- erated place can be plainly seen in the lower artery on the papilla. The white color of the fundus has passed off to a considerable extent. The cherr}' red spot is no longer so conspicuous, and there are signs of the coronula, which can be seen distinctly in Fig. 16. An area attached like a wing to the papilla has regained approximately its normal color. The vision remained lost in spite of the improvement in the objective symptoms. 1.58 Tab. 84. Fiir. 44. Fig. 45. PLATE XXV Fig. 46. Flat Detachment of the Retina Fig. 47. Partial Flat Detachment of the Retina Fig. 46. Flat Detachment of the Retina (See page 151) TIk' papilla is normal in every respect, as regards its color, margins, level, and vessels. The fuiulus lias, instead of its normal reddish color, a green gray appear- ance with bright and dark bands here and there. The vessels have many little tortuosities, such as are scarcely to be seen in any other condition. An artery makes a marked bend as it passes over the very white band. The entire picture seems quite dull, because the vessels have no light streaks, as is almost always the case in detachment. This is a picture of an almost total, but flat detachment of the retina. The detachment does not extend quite to the papilla, for if it did the mar- gins of the latter would be obscured, and then the picture would look like one of optic neuritis (see page 72). Naturally the vision is badly impaired. Fig. 47. Partial Flat Detachment of the Retina The papilla is normal. The retina in its vicinity presents discolored islands over which the vessels pass with a distinct bend. Outward and upward from the papilla is a large discolored place, which shows plainly several folds, over which the vessels of the retina deviate from their courses. On the other side of the papilla the retina is still attached and allows the markings of the chorioid to be seen distinctly through it. Some of these vessels are sclerosed, so we will make no mistake if we diagnose this as an arteriosclerotic detachment of the rttina. The retinal vessels have no light streaks, except in the portions that lie on the papilla. 160 Tab. as. Fig. 46. Fig. 47. PLATE XXVI Fig. 48. Large Gibbous Detachment of the Retina Fig. 49. Detachment of the Retina Caused by a Tumor of the Chorioid Fig. 48. Large Gibbous Detachment of the Retina (See page 152) This is a composite picture, wiiicli depicts wliat the observer may see at varying distances from the eye of the patient. Wlicn he focusses on the papilla the detached portion of the retina will be obscured, and, on tiie other hand, when he leans backward in order to see distinctly the detached portion, the region of the papilla becomes indistinct. The margins of the papilla are not (juite sharply defined. On its tem- poral side is a distinct conus. The vessels of the retina are in part accompanied by broad, white bands, which have been jiroduced by transudates that, in turn, are due to an existing nephritis. The detached retina protrudes very far forward, shows depressions and elevations, and exhibits distinct wavy movements whenever the patient moves his head. These are to be ascribed to the fluctuations of the fluid accumulated behind the retina. The detached portion was clear on transillumination with HirtzdV.s lamp. Fig. 49. Detachment of the Retina Caused by a Tumor of the Chorioid (See page 15'2) This is also a composite picture. Although it has a certain resemblance to the preceding, yet it presents certain characteristic differences. The line of demarcation of the detached portion is (juite sharp. The surface is smooth, tensely stretched, and in certain places the reddish color of the tumor can be seen shining through the retina over it. When the eye was transilluminated with HcrtzdVs lamp the region of the detachment appeared as a dark shadow. No fiuctuatinff movement could be seen when the head was moved. 162 Tab. 26. I'm. -IS. 1 1-. 4't. PLATE XXVII Fig. 50. Small Glioma of the Retina Fig. 50. Small Glioma of the Retina (See page 153) Such a picture as this is rarely to he seen, hecause glioma occurs in earlj childiiood and is not noticed in most cases, on account of tlie iihsenci' of sul)jective comphiints, until nearly the entire space of the vitreous has heen filled hy it so as to produce the so-called amaurotic cat's eye. But, as the tumor frequently appears in both eyes, it occasionally happens to those who habitually examine both eyes with the ophthalmoscope that they are able to see a glioma of the size here depicted. Tiie tumor apparently starts from the vicinity of the papilla, which is overlaid by it, and measures Sl^X^J^L) !'• D., i.e., 5ViX6% mm. It is therefore in reality about as large as a pea. This picture was taken in January, 1910; in ]March the tumor was as large as a bean, by October it had filled the entire vitreous, in December, 1911, it broke through the eye- ball, and then tlie proliferation advanced very rapidly, so that at the time of the death of the child, in jMay, 1912, the tumor was as large as an apple and protruded from the orbit. The similarity of the picture to the preceding ones is very great, but it is to be noticed that some of the vessels of the retina lie in the tissue of the tumor itself. At the upper pole of the tumor may be seen several black spots and one large patch of atrophy, which indicate a simultaneous disease of tile chorioid : whether or not this h;id anv etiolr)gical connection with the tumor could not be determined. The liemorrhages near the papilla are uncommon. The bright zone about tlie tumor shows that the pigment epi- thelium of the retina is also involved. 164 Tab. 27. Fig. 50. Chorioid Chorioid Preliminary Remarks on the Anatomy The chorioid is rightly named, for it consists essentially of vessels whicli furnish nutrition to the macula and the outer layers of the retina. On account of the great abundance of blood vessels the thickness of this membrane varies in proportion to the degree to which they are filled, and varies also in different places, from 0.05 or 0.08 mm, at the place where it passes over into the ora serrata, to 0.1 or 0.2 mm about the posterior pole. It is very loosely connected with the sclera (Fig. 54, S) through 1, the lamina suprachorioidea (Su). The space between the two mem- branes, which is demonstrable only under pathological conditions, is known as the perichorioidal space. This lamina contains many pigment cells and elas- tic fibers, hut no vessels. Then comes 2, the lamina vasculosa, the layer of the larger vessels. Next is 3, the choriocapillaris, the layer of capillaries, which is of the greatest importance in the pathology of the diseases of the chorioid and the retina. Adjoining this is 4, the lamina vitrea, also called the lamina elastica and the lamina basalis. Finally comes 5, the layer of pigment epithelium, which appertains to the retin;i (see page 111), but must be mentioned in this place on account of its intimate pathological relations to the chorioid. The vascular supply is through the so-called ciliary vessels, which come from the ophthalmic artery. They consist of from -t to 6 short, and 2 long posterior ciliary arteries, which enter the eyeball near the optic nerve, and 4 anterior, which enter near the limbus. The anterior ciliary arteries run first in the four recti muscles, which they supply, and divide, each into two branches, before they reach the limbus. The short posterior arteries branch very quickly after they have passed through the sclera and the lamina suprachorioidea, and form the main part of the arteries of the chorioid. The long posterior arteries pass without branching in the layer of large vessels to the ciliary body, where they empty into the circulus arteriosus iridis together with the anterior ciliary arteries, but before doing so they give off recurrent branches which unite with the capillaries of the short posterior arteries. The short posterior ciliar}' arteries likewise form a circulus arteriosus in 167 168 the scli'Di, wliic'li surrouiuls the papilla ,uhI forms a coiiiicction between tlie ciliary and the retinal vessels. Tiiis is known as the ciriniliis artei-iosus iiervi optic'i, or the circle of Zlnn. This connection is of but little practical im- portance because it never happens that a central artery of the retina which is obstructed in its central j)()rti(>n is sufficiently supplied with blood throuf;-h this means. The chorioid may be divided into two very uneciual portions, according to the arterial supply, the posterior and lai-(^er of which extends from the ])apilla into the region of the eijuator, tlu' anterior from this point to its transition into the ciliary body. The former is sup])lied by the short posterior ciliary arteries, which therefore form the jirincipal source of the nutrition of the chorioid, while the second receives its blood throufrji the recurrent branches of the long posterior ciliary arteries. The anterior ciliary arteries arc of importance to the chorioid only in so far as they unite with the long posterior, through the eirculus arteriosus iridis major, and thert'by with the short posterior ciliai'y arteries, but this indirect connection with the nutrition of the globe is of practical value, for it is able to preserve the latter when all of the posterior arteries have been divided, as when the retrobulbar space has been exenterated in the removal of a tumor. The equatorial portion has the poorest supply, which comes only through the terminal filaments of the short posterior, and of the recurrent branches of the long posterior arteries. It is therefore not an accident that this por- tion is the first, or the main one to be affected when degenerative processes take place in the eye, as in chorioretinitis pigmentosa, and hereditary syphilis. The venous outflow of the chorioid is quite different from its arterial supply, as its veins carry away not only tlu' blood from the chorioid itself, but also that from the ciliary body and the iris. C'onse(iuently they are far more numerous than the arteries and have many more anastomoses. They connnonly pass from the chorioid into the sclera behind the etjuator of the eye in the form of from i to 6 large vessels. In rare cases they end at the posterior pole (Fig. 3), principally in eyes that are higlily myopic. The chorioid contains besides vessels many collagenous fibrils and elastic fibers, as well as a great (juantity of cliiomatophores laden with pigment. The latter are to be found in all of the layers of the chorioid, with the exception of the choriocapillaris, and naturall}' of the lamina vitrea, but especially in the spaces between the vessels. General Diagnosis of Diseases of the Chorioid, so far as They are Caused by Diseases of the Vessels The schematic drawing. Fig. 54, is, with r material changes, the same as that used by Krueckmann in Axcnfcld's text-book. The pictures in the circles show typical changes that are to be ol)seryed 16!) in diseases of the vessels of the cliorioid. A glance !it the succeeding plates, whicli arc not schematic, for example, at Fig. 74, reveals at once a resem- blance to tiie distiirhanees here delineated schematically. Near each cliange is presented the corresponding microscopical picture. The retina is absent from all except Number \'l, for tliis must be understood to be changed in all, with tiie exception of Number I of course, because, as has been said repeatedly, the outer layers of the retina receive their nutrition from tlie cliorioid, anil disturbances in the vessels of tiiis membrane nmst naturally manifest themselves tiirough nutritive derangements of the corre- sponding portions of the retina. I. Picture I shows oplithalmoscopically a perfectly normal condition, which is likewise normal microscopically. S indicates the sclera ; Su the lamina suprachorioidea ; V the layer of large vessels; Ch the choriocapillaris ; L the lamina vitrea; E tlie pigment epitlielium of the retina, or at least its layer of basal cells. The latter is in tiiis example perfectly uniform and no*: trans- parent, so that the cliorioid cannot be seen. II. In picture II the pigment epithelium is destroyed to a considerable extent as tlie result of disease of tlie subjacent choriocapillaris; it is made homogeneous, if one may use such an expression. In consequence of the break- ing down of this layer the larger vessels of the cliorioid can be seen in the form of a relatively bright network on a dark backgrouiul, because of the pigment tiiat lies between them. Tlicy appear to be of a normal color and they are found to be normal under the microscope. III. The process has extended fartiier. The pigment epithelium and the choriocapillaris iiave coiiiplettly disappeared. Portions of the larger vessels also are obliterated (A) (a), and conse(]uently appear in tiie ophthalmoscopic picture as white cords. The vessel B on the otiier liand is in a normal condition. I\ . This presents a still further advanced stage. The vessels of the cliorioid are almost totally obliterated (C), the vessel D alone still contains a slender column of blood within its thickened walls. \. The cliorioid has almost wliollv disa])peared ; tiaces only of the intra- vascular pigment can be seen. As there is no pigment in the places formerly occupied by the chorioidal vessels the spaces formed by their absence have their forms and courses. When these traces of pigment disappear the pure white sclera is laid bare. VI. This shows the way in which tlie black spots are brought about. Here, as in II, tlie choriocapillaris lias been destroyed, but at the same time bands of tissue have been formt'd wiiit'ii iiave in their spaces newly formed pigment cells, and as these lie one behind another they give oplithalmoscopically the impression of a dark, black spot. Further, the picture shows the second- ary pigmentation of the retina that appears in diseases of the chorioid. This is brought about by tju' likiiding of the processes of the pigment cells with the glia tissue, especially with MitclU-r'.i supporting cells, so that 170 the brown frraniilcs of fiisciii pcnetnifc into the retina. It is solf-o\ idcnt that neuli) fornud pigment epithelium can also proliferate into the degenerated chorioid. ]Vliiit 7CC learn from these schematie pictures in that not onhi abnormal pigmentations, btit depigmentations as uril, are to he looheil upon as signs of disease of tin clmrioid. It may he empliasi/ed again that pigment is to be seen normally in the fundus in two jilaces : 1. The pigment laijer of tlw retina, wiiieh covers the chorioid and limits tiie viiw with the ophthalmoscope. It is only when tiie nutrition of this layer is impaired by a disease of the ehoriocapillaris, and is thus caused to atrophy, that the markings of the chorioid can he seen. Hut it must he remembered that similar ])icturcs may be ijrought about by a congenital partial or total abscnci' of this pigment layer, as in albinism. In such cases, however, there is none of the abnormal heaping of pigment and disease of the vessels that is to be seen in every pathological case. Compare the periphery of Fig. 57 "ith l''ig. 8. 2. The pigment of the ehorioid, whicli lies in the spaces between the vessels of this membrane and may last very long in spite of serious chorioidal disease. The general statement may be made that an abnormal heajiing of pigment takes place at the same time 7cherever pigment is destrot/ed. Pig- ment can migrate into the retina only when the lamina vitrea has been injured, lu ncc it is that colloid deposits can fretjuently be seen on this lamina (Fig. 41) ill association witii pigmentations of the retina. Etiology of Cliorioiditis. Almost all diseases of the chorioid are sijmjitomatic of general diseases, with the exception of those that are due to traumatism and some conditions that are congenital. Therefore a very thorough general craniination is indi- cated in all such cases, just the same as in retinitis. Although certain con- clusions can be drawn in a number of cases from the position, color, size, and appearance of the lesion, yd the etiology must be determined mainly by such an examination. This is particularly true for the general practitioner, who can sec the black s])ots with the ophthalmoscope, but may not perceive or interpret the nu'nuter dift'erences, on account of his lack of special practice. The following proposition is particularly applicable to him: // black or white spots are present in the fundus a thorough examination must be made of the organism, zehich is not to he confined to the ordinary physical and chemical methods (done, but in which the tuberculin and Wassermann tests are to be made. A guide to the etiology is fre(iuently to be found in other ocular symptoms; for example, if the cornea is investigated with the binocular loupe and tleeply situated vessels, or fine, central, parencliymatous opacities are found, which indicate a past interstitial keratitis and may persist for years after the subsidence of such an inflammation, wc have obtained an almost 171 positive proof of the syphilitic origin of the disease. Dots of pigment in tlie pupils of young persons, whicli are to he considered as traces of a bygone iritis, point toward the same etiology, because iritis is usually of sy])hilitic origin in yoinig persons. The following conclusion can be drawn from the ophthalmoseojjic picture if we look for changes in the vessels. // sclerosed vessels tire present in the chorioid the probable cause of the disease is cither st/phiUs, arteriosclerosis, or nephritis; if no such vessels arc present the probabje cause is tuberculosis. In a small number of cases the ilisease in the chorioid is of a metastatic pysemic nature, but these are usually associated with a sinmltaneous disease of the iris and ciliary body, and, as tiiese ordinarily induce a great opacity of the refractive media, the lesions in the chorioid are not to be seen with the ophthahnoscope as a rule. Consequently they do not come into con- sideration in this place. DIAGNOSIS A. General Diagnosis After the diagnosis of a disease of the chorioid has been made the following points need to be taken into account in order to establish its etiology: 1, the position of the lesions in the chorioid; 2, the sort of pigmentation, or depigmentation ; 3, whether changes are present in the vessels or not; 4, the form of the change in the chorioid; 5, the differences of level. Although we cannot duduce tlic ctiolo. A wvy had casu of tliis nature is shown in Fitic nerve is atropiiie. 2. Superficial Dcpigmcntdt'toiis, as tlie result of thi' destruction of thi' chorioeapillaris, ari' likewise often due to hereditary syphilis. The peripheral part of the fundus is hrightencd and the large vessels of the chorioid can be seen, although they are invisible in the central j)ortion. This can lie distinguished from a partial albinism, such as is shown in Fig. 8, by the smallness of the arteries of the retina and the presence of detached spots of pigment. These depigmentations, which are usually found only of the extent and intensity depicted in Fig. 57, may spread more or less over the fundus in exceptional cases, but even tlun they are most marked in the periphery. Fig. 58 is a picture of such a case, in which the retina and optic nerve were involved as well as the chorioid. (b) Changes in the Chorioid in the Region of the Macula The tliffuse changes in the chorioid, which will be desci-ibed lati'r, may involve the region of the macula under certain conditions, as shown in Fig. 80, but it is proposed to deal in this place only with the typical diseases of the macula that are characterized by certain peculiarities. It may be stated here that in the beginning of a disease of the macula the region of the latter appears to be slightly hazy, and that the reflex ring about it is abolished. 1. Arteriosclerotic Changes in the Macula. This is often called senile degeneration, yet it is by no means confined to old age, for premature arteriosclerosis may occur in young persons occa- sionall}^ the same as senile cataract. The varying types and intensity of such changes are depicted in Figs. 59 to 62. The markings of the chorioid stand out with vuiusual distinctness, perhaps with abnormal touches of pig- ment, or little bright, yellowish, or reddish yellow points may be seen with a more or less abundant proliferation of pigment between them. Colloid deposits are sometimes found in their vicinity. The changes are very trivial ivnd cause no symptoms at all, unless they happen to be situated in the center of the macula. Aside from these relatively insignificant changes in the macula, which arc not infrequently associated with a development of connective tissue, scleroses are to be found in the large vessels, as shown in Fig. 64. Such an arteriosclerosis can be simulated, in rare cases, by a nephritic disease of the vessels of the chorioid, but it rarely happens, in such cases, that such lesions of the retina as oedema and hemorrhages are lacking (see the nasal side of the papilla in Fig. 69)- 177 2 ..Changes in the Macula Cauxid by Contusions, or b/j the Presence of a Foreign Body in the Eye resemble closely those that have just been described. For tliis reason, and because it is quite seldom that they are to l)e seen, it does not seem best to devote a picture to tiiem. 3. The Changes in the Macula Caused by High Myopia have been thus described by r. Michel: "Sometimes little brigiit spaces are found in the layer of pigment epithe- lium, and at the same time small heaps of pigment, or short bright stripes, arranged in rows or formed into a network. In many cases whiti.sh band.s or lines, not edged with pigment, extend out from tlie margins of the staphy- loma, which are joined in the region of the macula l)y transverse lines (Fig. 71), or yellowish points may be visible near one another. In other cases a hemorrhage, or a dirty gray, or greenish little elevation, or a deep black spot of pigment, takes the place of the macula, when hemorrhages may be present in the vicinity, and it sometimes happens that a thrombosed vein of the chorioid is to be seen, running near the entrance of the optic nerve and toward tiie macula. Aside from the possibility of an innnediate extension of the staphyloma to the region of tiie macula in cases of high myopia, tlie place of the macula may be occupied by a single white, sharply defined large spot (Fig. 72), or several smaller ones of the same nature, bordered by a more or less broad, often irregular, fringclike edge of pigment, frequently in the form of a ring."' The changes that take place on the papilla, as well as the shadows ef the so-called stapjiyloma verum (Fig. 73), have been mentioned on page 37. These changes in myopia are to be ascribed to the eft'tct of the stretching exerted upon the vessels of the chorioid, and upon the tissue of both this memlu'ane and tlie retina, in the temporal portion of tlie posterior segmenb of the globe, which sometimes causes ruptures and apertures in the elastic lamina, as well as disease of the chorioidal vessels. 4. Tlie So-called Coloboma of the Macula. This is a roundish, or transversely oval spot in the region of the macula, which measures 3 P. D. horizontally by from 1 to 3 P. D. verticallv, has an edge of pigment, and usually present a network of tlie same. Its comparatively large size and its regular margins differentiate this from other spots in the chorioid, with which it is frequently associated. (c) The Changes in the Chorioid about the Optic Nerve, such as the conus, the staphyloma, the halo, and jieripapillary atrophy of the vessels, have been dealt with for the most part on page 33. 178 Peripapillary Sclerosis of the Vessels may be nientiontd afraiii. Arteriosclerosis affects two regions, tliat of the macula, and that of the entrance of tlie optic nerve. In Fig. 65 may he seen plainly sclerosed large vessels, some of them still containing .slender columns of blood, which resemble those shown in the schematic drawing in Fig. 54. Tiiis form of atrophy of the chorioid is commonly progressive, and may spread from this place over the entire fundus (Fig. 67). More or less abundant, irregular heaps of pigment appear at the same time. The vessels of the retina may, or may not be involved in the sclerosis. The prognosis of sclerosis of the vessels of tlie chorioid is by no means as bad as that of sclero.sis of those of the retina (see page 1.'53). Such an extensive vascular sclerosis may be cau.sed by hereditary syphilis in exceptional cases. Fig. 68 portrays a case of this nature in which the vessels of tiie chorioid were sclerotic over almost tlie entire fundus. It is only in the region of the macula tiiat a place can be seen which, although changes are present, is still capable of performing its functions. Ruptures of the Chorioid are characteristically situate'! about tlie entrance of tlie optic nerve (see page 12(5 and Fig. 83). Tliis is true also of the typical Coloboma of the Chorioid (Figs. 84 and 85). Colobomata of tlie chorioid lie behiw tlie })a]jilla, in the inverted image above, and have the form of an egg, or of a shield. The greater diameter is always vertical. The color is a brilliant white, with which a gray blue tone is often mixed, and sometimes some brownish ])laces can be seen. A special tinting is given by irregular excavations which form little hills and valleys. In many cases the coloboma is bordered by a sharply defined, black edge of pigment, and flecks of pigment can often be seen in the coloboni.i itself. In addition to the vessels of the retina, which run smoothly over the white surface, branches of the ciliary vessels that pierce the sclera can usually be seen ; these are often twisted like corkscrews. The size of the coloboma varies; in many cases it is situated quite peripherally and can be seen only when the patient looks far downward, in oth( rs it begins just below the papilla (Fig. 84), and it may extend above the disk and involve the macula (Fig. 85). The extent of a coloboma does not necessarily accord with a correspond- ing defect in the field of vision ; on the contrary, the latter may sometimes be perfectly normal; this depends on the extent to which the retina is involved. A coloboma is to be considered as a true arrest of development, due to a faulty closure of the fetal ocular cleft. Frequently it is met with in com- 179 pany witli othor inalforinations of the eye, such as colohonia of tlic iris, micropiitiiahiios, straliisimis, ami nystafrimis, as well as of other parts of the body. An ophtiialiiioseo|)ie picture wiiich is seldom seen is known as coloboma of the optic nerve. The papilla is doubled in size and appears as a roundish, or vertically oval hollow. (d) The Disseminated Form of Chorioretinitis is characterized by the fact that it appi'ars in multiple spots, little if any larger than the papilla, wiiich are usually situated at the posterior pole of the eyeball. These spots may be fresh or old. Fresh spots are small, roundish, rarely elongated, gray, and about a quar- ter of the size of the papilla when they are not confluent. The spots them- selves cannot be seen, the accompanying a?dcma of the retina alone is visible. They can be perceived most readily when a vessel of the retina happens to pass over them (see the vein running downward and inward in Fig. 78); the vessel is raised at such a place, is wavy, and in many ca.ses is covered partly or wholly by the oedema. These spots are usually caused bv tuberculosis or syphilis. The latter dis- ease is particularly to be suspected when they lie in the anterior segment of the chorioid, and when the diagnostic signs mentioned on j^age 170, deep ves- sels and central opacities of the cornea, dots of pigment on the lens, and sclerotic vessels of the chorioid, are present. But syphilitic diseases of the chorioid very often manifest themselves from the start through a sclerosis of its vessels (compare with the schematic drawings in Fig. 54)- With regard to the differential diagnosis from spots having a similar ap- pearance, see page 126. Old atrophic spots are found in a great variety of forms. The develop- ment of a fresh spot into an atrophic one can be watched in comparatively few cases. We usually see the picture produced by the bygone process and have to try to draw conclusions from it. It is clear at once in most cases that the spot is chorioiditic and not retinitic, for a pigmentation characteris- tic of a chorioiditic spot is almost never lacking cither in the spot itself, or in its immediate vicinity. Syphilitic spots are usually nnich more abundantly pigmented than the tuberculosis, so that a weak pigmentation is indicative of tuberculosis. The color may be j^ellowish, yellowish graj', or pure white; this depends on whether portions of the choi'ioid are present, or the mem- brane has been completely destroyed. The white color is brought about either by the sclera shining through the atro[)hic chorioid. or by the forma- tion of a hyaline, cicatricial, connective tissue in the place of the membrane that has been desti-oyed. Atrophic spots are divided i:ito two varieties: 1, Those that are •without visible changes in the vessels; 2, Those that are Kith visible changes in the vessels. Tuberculosis is the principal cause in cases that belong to the first group, 180 while svpliilii^, iirtcTio.sck'rosi.s, and iRphritis must be taken into account in those that belong to the second. 1. Atrophic Spots Wittioiit Visilile ('liaiificft in the Vt'sacls. One of the most important services rendered to the world by v. Michel was to call attention to tul)erculosis as one of the main causes of chorio- retinitis. Altliollfi'ii this idea met at first with the stron^rest opposition, he had tlie satisfaction of seeing it adopted by almost all ophthalmologists. It was he also who pointed out the diagnostic importance of the changes in the vessels. Although we nnist generally leave the final determination of the etiologv o"^ ^ ^^^ft^':^ -^^^-^^^ %^l:;;::fe Fiu. 54. . =»-- ' _ - -_-• <^- - r Chorioid !• Retina / PLATE XXXI Fig. 55. The So-called Pepper and Salt Fundus of Hereditary Syphilis Fig. 56. Very Severe Chorioretinitis Due to Hereditary Syphilis, with Atrophy of the Optic Nerve Fig. 55. The So-called Pepper and Salt Fundus of Hereditary Syphilis (Sec page 175) The papilla and tlie vessels ol' the ri'tina are normal. The density "f the pigment epitluiiinn varies in ditt'erent parts of the fundus. In some ))laces it hides the chorioid completely, in other.s the markings of the latter arc plainly visible. A j)atch of distinctly sclerosed vessels is to be seen in the vicinity of the optic nerve. The characteristic feature in this fundus is the presence of mnnerous little, roundish depigmentations, which arc often sur- rounded by lialos of denser pigment. Fig. 56. Very Severe Chorioretinitis Due to Hereditary Syphilis, with Atrophy of the Optic Nerve This picture was taken from the eye of a hoy l.'J years old. The most striking feature is the almo.st total absence of retinal vessels, of which onlv very small, sclerosed traces can be seen in the innnediate vicinity of the papilla. The papilla itself is perfectly white. On account of the total absence of an excavation and the invisibility of the meshes of the lamina cribrosa, the atrophy must be supposed to be of inflammatory oi'igin in spite of the fairly sharp margins. Sharp margins are rather frequently found in cases of niuritic atroj)hy that develop iluring childhood. Near the papilla can be seen some sclerosed vessels of the clioi-ioid. The rest of the fundus is of a dirty gray color, in which few details are visible, with the exception of a few dots of pigment and some bright spots that faintly remind one of the depigmentations si^en in the preceding picture. Some of the vessels of the chorioid are also visible in the uppermost })art. This boy had suffered from an attack of syphilitic meningitis in early childhood, which caused an optic neuritis with a subsequent atrophy, and at the same time the serious disease of the vessels of the retina and chorioid asserted itself. The vision of this eye naturally was nil. 190 Tab. 31. Fig;. 55. I'ig. 56. PLATE XXXII Fig. 57. Chorioretinitis Due to Hereditary Syphilis Fig. 57. Chorioretinitis Due to Hereditary Syphilis Tliis picture presents anotlier type of hereditary syphilis of tlie eye. The papilla is rather paler than normal, especially in its temporal half. The arteries of the retina are very small. Some of the veins of the retina have well marked mantles of pigment in their peripheral portions. Only a few spots of pigment surrounded by bright areola* can be seen in the periphery. The markings of the chorioid can be seen very plainly in the periphery. This is because the pigment epithelium and the choriocapillaris have been destroyed (sec page 176). 192 Tab. 32. PLATE XXXIII Fig. 58. Chorioretinitis Due to Hereditary Syphilis, with Atrophy of the Optic Nerve Fig. 58. Chorioretinitis Due to Hereditary Syphilis, with Atrophy of the Optic Nerve As in tln' case depicted in Fig. 56, Hh' condition here presented was preceded by a meningitis, a consequence of which was tlio atropliy of the papilhi, which is surrounded b_v a very distinct ring of glia tissue. The vessels of the retina arc very small and drawn out. The entire funilus shows a iiigh degree of depigmentation, with the remains of the {)ignient grouped about separate roundish foci, whicli call to mind Fig. 55. It cannot lie determined with certainty whether the crescentic reddish spot in the macuLa is a hemorrhage, or a deposit of pigment, because many of the small spots of pigment exhibit a reddish tone of color. 194 Tab. 3»- Fig;. 5S. PLATE XXXIV Fig. 59. Early Stage of Arteriosclerosis of the Vessels of the Chorioid in the Region of the Macula Fig. 60. Senile Degeneration of the Macula Fig. 61. Senile Degeneration of the Macula Fig. 62. Senile Degeneration of the Macula Fig. 59. Early Stage of Arteriosclerosis of the Vessels of the Chorioid in the Region of the Macula (S(v \mgv lT(i) In this picture, taken from tlic eye of a man fiO years old, some of the vessels of the chorioid can be sien plainly in the macula. The fundus is otherwise normal. 'I'lie place is surrounded hy a circle of very minute bright spots. Tile explanation of this picture is that a portion of the pigment epithe- lium has !)een caused to atro[)hy by a disease of the ciloriocapillaris, and tliat consi'([uen( ly the rionnally colored large vessels of the chorioid have become visible. The white spots are due to colloid deposits on the viti'eous lamella. The vision in this case was y^ of the normal. Fig. 60. Senile Degeneration of the Macula (See page 17()) In this case also some large vessels of the chorioid arc visible, with a number of fine points of pigment mar them; otherwise the fundus is normal. Vision was reduced to ^s- The {)igment epithelium of tl-.e retina and the ciloriocapillaris must have been destroved, for otherwise the markings of the chorioid could not be seen. Fig. 61. Senile Degeneration of the Macula (See })age 17()) Another form of degeneration in the macula is shown in this picture. A number of very minute, bright points are to be seen lying in a bed of pigment gramiles. Some areas of depigmentation are visible in the peri()hery. The ])aj)illa is too red in the picture, and the conus is too white, it should in fact be rather yellow. The spot of pigment is a portion of the pigment ring and denotes nothing pathological. Fig. 62. Senile Degeneration of the Macula (Sec page 176) The changes in this picture arc similar to, but grosser than those seen in Fig. 61. The papilla is surrounded by a white band that is too broad to be a physiological connective tissue ring. It must be su])posed to be a senile halo, although its color is not quite right for this condition. The pigmented edge is likewise broader than the physiological pigment ring, and must be considered to be jiathological. 196 Tab. :H. Fig. 59. rig. 60. i ]". 61 hig. 02. PLATE XXXV Fig. 63. Finely Pigmented Fundus of Hereditary Syphilis, the So-called Snuff Fundus Fig. 64. Sclerosis of the Vessels of the Chorioid in the Region of the Macula Fig. 63. Finely Pigmented Fundus of Hereditary Syphilis, the So-called SnufF Fundus (See page 175) Tliis is till' siiiifl' fundus, :\. (iiK'ly pigiuriilrd tv])c wliicli is met with in liei-editarv svpiiilis, in addition to the grossly pitiincnti'd one shown in Fig. 53. Such a typical and distinctive picture as the one depicted lierc is seen comparatively rarely, but a less pronounced form is mot with very often. Tlu' papilla and retina arc intact, the chorioid alone presents lesions, which ai'e seen with the microscope to i)c a disease of tiie choriocapillaris with secondary disturhancis of tiie pigment, and manifest themselvi^s ophthalmo- scopicalij as finely granular heaps of pigment and round foci of degeneration. Fig. 64. Sclerosis of the Vessels of the Chorioid in the Region of the Macula (Sec page 178) This could also be called a senile degeneration of the macula if we were not accustomed to designate by this term sucii insignificant changes as those depicted in Figs. 59 to 62. The fundus is of the tessellated type, so tiiat the vessels of the chorioid, with the deposits of pigment between tiiem, are plainly visil)le in consequence of the thinness of the ])igment ej)ithelium. The vessels of the chorioid in the region of the macula are sclerosed, i.e., their wails have become thickened. 'I'lie thickening of the walls is so great in places that a cokunn of blood is no longer visible in some of the vessels, while only a slender column can be seen in the center of others. The papilla is normal, the retinal arteries are rather small. The reduction of vision is naturally very great in such cases; in this case the patient could only count fingers at 2 meters. 198 Tab. 35. Fie. f>3. Fig. 64. PLATE XXXVI Fig. 65. Peripapillary Sclerosis of the Vessels of the Chorioid Fig. 66. Peripheral Patch of Sclerosis of the Vessels of the Chorioid Fig. 65. Peripapillary Sclerosis of the Vessels of the Chorioid (See pages 39 and 178) Tlie vicinity of the papilla, as well as that of the macula, is a favorite place for sclerosis to attack the vessels of the chorioid. In several places the vessels may tie seen to he wholly obliterated, while in others they are only ])artly filled with blood. Fig. 66. Peripheral Patch of Sclerosis of the Vessels of the Chorioid This might be mistaken at first glance for a coloboma of the ciiorioid if the intervascular spaces could not be seen so plainly. The vessels them- selves are wholly obliterated and invisible. The reason why they still seem to be present is that the pigment which is normally situated between them still remains visible after they have disappeared, and outline the empty spaces left by them (comjiare with Plate XXX). If this pigment also should disapj)ear a uniform white surface would be left. The lumps of pigment on the margin are due to proliferations of pigment. The presence of newly formed vessels renders it very probable that this condition was one of inflam- matory origin (see page 104), 200 Tab. 3«. Fisi. 65. f-i". tiO. PLATE XXXVII Fig. 67. Great Sclerosis of the Vessels of the Chorioid, and Less of Those of the Retina Fig. 68. Extreme Sclerosis of the Vessels of the Chorioid Fig. 67. Great Sclerosis of the Vessels of the Chorioid, and Less of Those of the Retina (Sec page ISO) All of the vessels of the cliorioiil that arc \isii)l(' are sclerosed, and only a few of thuiii contain slender colunnis of blood. The pigment epitheliinn must have been destro^'ed very extensively; the heaping up of pigment in various places is in harmony with such a destruction. The papilla is rather ]).iler than normal (see page .55), and the vcssejs of the retina, particularly the arteries, are evidently contracted (see page 98). Fig. 68. Extreme Sclerosis of the Vessels of the Chorioid (See page 176) The sclerosis is still more extensive in this case, and has reached a nmch greater intensity. While the intervascular pigment of the chorioid was pre- served throughout its normal extent in the jireceding case, in this one it is so atrophic that the time seems to he not far distant when the entire fundus will he transformed into a white surface. The region of the macula shows a trace of pigment epithelium, vet this also is changed. The papilla and the vessels of the retina are normal. This vision was comparatively good, ^(i of the normal, hut the visual field was concentrically contracted to an extremely small trace. This case was met with in a girl 13 years of age who had hereditary syphilis. Her sister had a similar condition. 202 Tab. 37. f-'ig. OS. PLATE XXXVIII Fig. 69. Chorioretinitis Albuminurica Fig. 69. Chorioretinitis Albuminurica (See page lli'S) A picture similar to the preceding one may be produced by renal disease. In such cases, which are pretty rare, the signs of inflammation on the papilla and in the retina can scarcely be missed. In the present case the nasal side of the papilla is distinctly hazy. The retina shows plain signs of oedema by the haziness of its vessels, and contains some hemorrhages. The vision is greatly impaired in such a case; in this patient it was reduced to counting fingers at 2 meters. 204 Tab. 38. Fig. 6Q. PLATE XXXIX Fig. 70. High Myopia; Temporal Staphyloma; Change in the Macula Fig. 71. High Myopia; Circular Staphyloma; Sclerosed Vessels of the Chorioid Fig. 70. High Myopia; Temporal Staphyloma; Change in the Macula (Seepages .'J7 imd 177) The papilla, which is vertically oval in this case, has a strikingly indis- tinct temporal margin; it seems to blend at this place with the staphyloma, which is situated altogether on its temporal side. See page .'38 for the rela- tions l)etween the form of the papilla and that of the staphyloma. The latter is divided into 2 portions, one situated near the papilla, in wiiich piimtatc markings can be seen, the other farther away, which is pure white. The punctate markings are due to traces of chorioidal pigment that have been left after destruction of the vessels of the chorioid (see page 37). The vessels of the chorioid can be seen plainly in this very pale fundus, as well as some chorioidal hemorrhages to the nasal side of the papilla. In the region of the macula is a maze of white cords, which are explained by some as sclerosed vessels of the chorioid, by others as fissures in the pigment epithelium (see page 37). Fig. 71. High Myopia; Circular Staphyloma; Sclerosed Vessels of the Chorioid (See pages 37 and 177) This picture presents all of the characteristics of a myopic eye; staphy- loma, pale fundus, stretched vessels of the retina, sclerosed ones of the chori- oid. The papilla is normal, and is surrounded by a circular staphyloma, in the nasal side of which some traces of chorioidal pigment and one normal chorioidal vessel can be seen; all the other details have been destroyed. The rest of the chorioidal vessels can be seen very well in the pale fundus. The region of the macula, which is rather richly pigmented, shows a peculiar maze of white cords with little processes that remind one of the frosted branches of a tree. Some dots of pigment and some rather superficial depigmentations are also to be seen. It cannot be told with certainty whether all of the white cords are sclerosed vessels of the chorioid, or a part of them are due to fissures in the pigment epithelium (see page 37). The myopia in this case was 12 diopters. 206 Tab. :J9. Fig. 70. -ig. i\ PLATE XL Fig. 72. High Myopia with Circular Staphyloma and a Very Great Change in the Macula Fig. 73. High Myopia with a So-called Staphyloma Verum Fig. 72. High Myopia with Circular Staphyloma and a Very Great Change in the Macula (Sec pages .'57 aiul 182) Tlu' I'uiulus is Vfi'V pale, and soiiir of the vessels of the ehoriold can he seen (jiiitt' plainly, as often ha])])(iis in myopia. This is hecaiise of the stretching of the layer of pigment epithelium. The vessel.s of the retina arc extremely drawn out and are smaller than normal. The papilla is surrounded by a circular staphyloma which is broadest upward and outwaid. A very careful examination re\eals some remains of ehoi-ioidal pigment, uhicli is the last trace of the ehorioid that has vuidergone atropiiy. The staphyloma is surrounded by a more or less strongly pigmented zone. Some small atrophic spots may be seen to its nasal side. The region of the macula is occu])ied by a large, kidney-shaptd spot, measuring 2X21/^ papillary diameters, in the liilus of which is a spot as large as the papilla, composed of numerous dots of pigment. Above and below the latter lie several smaller spots of pigment, which are to be distinguished from the remaining chorioidal pigment by the intensity of their color. Sclerosed yessels of the ehorioid, intermixed with white and black spots, lie to both the temporal and the nasal sides of this principal spot. The vision in this casi- was counting fingers at 2 meters with the correcting glass, — 1(5 U sph. ^ — 2 D cyl. Fig. 73. High Myopia with a So-called Staphyloma Verum ( See })age 2() ) The papilla appears to be remarkably small, an optical illusion caused by the high degree of myopia (see page 17). It is surrounded by a circular staphyloma, which indicates tliat the vicinity of the papilla is pouched out rather luiiformly (see page 38 concerning the form of the staphyloma). Parallel to the nasal margin of the papilla are to be seen one large and two small gray, or rcdtlish gray, curved lines, in the region of which the vessels of the retina plainly bend. They are shadows cast by the margins of the protrusion of the posterior pole, sclerectasia, and consequently this has been termed staphyloma verum. Throughout its area the fundus is considerably brighter than it is elsewhere, because of the great stretching of the pigment epithelium. The vessels are extremely small, partly because of the stretching, partly because of an optical illusion. The arteries are drawn out, the veins are very tortuous, an unusual symptom in myopia, which may perhaps indi- cate a threatened detachment of the retina. Part of the vessels of the ehorioid are very clearly visible and some con- verge toward the papilla (compare with Fig. 3). In the region of the macula these vessels are distinctly sclerosed in places, a preliminary stage of a greater change in the macula, such as may be seen, for example, in Fig. 71. The myqpia in this case was ap])roximately 35 diopters. 208 Tab. 40. t^iii. 72. Fi". 73. PLATE XLI Fig. 74. Atrophic Spots in the Chorioid with Plainly Sclerosed Vessels Fig. 75. Neuritic Atrophy of the Optic Nerve; Atrophic Spot in the Periphery Fig. 74. Atrophic Spots in the Chorioid with Plainly Sclerosed Vessels (See page 180) Two .sli;ir])ly circumscribod spots of atrophy arc to be seen in an otlier- wise normal fundus, one in, the other beh)w tiic macuhi. The lower one resembles very closely one of the schematic drawings on Plate XXX. Scler- osed chorioidal vessels are to be seen with some pigment between them, hut the latter has begun to disappear, so it is to be expected that the spot will be perfect!}' white within a short time, as the sclera will then be laid bare. Two of the vessels still contain blood, liut the others are completely sclerosed. The spot is bordered by a ring of pigment. The upper spot, which is due to the same cause as the lower, exhibits an abundant development of pigment, which forms a mass so shaped as to divide the spot into ■! smaller ones. The pigment epithelium has begun to become lighter in its neighborhood. As soon as sclerosed vessels are noticed in the fundus we have to think chiefly of arteriosclerosis, syphilis, or nephritis as the cause, in the absence of niyoj)ia. Syphilis was the cause in this case. Fig. 75. Neuritic Atrophy of the Optic Nerve; Atrophic Spot in the Periphery The atrophy of the papilla is shown to be neuritic by the indistinct mar- gins and the great haziness of its surroundings. The latter indicates that the retina was involved to quite a considerable degree, and that the case was a very severe one of neuroretinitis. This corresponds to the actual conditions, for a choked disk preceded the atrophy and was caused by a gumma of the orbital portion of the optic nerve. The absence of any sheathing of the retinal vessels is noticeable. The pigment epithelium is denser in the upper part of the fundus than in the lower, so that the markings of the chorioid arc not as clearly visible above, but otherwise the rest of tlie fundus is normal, except for a peculiar change to be seen in the extreme periphery, where a whitisli spot with sharp outlines stands out amid normal surroundings. It is formed from more or less sclerosed vessels of the chorioid, between which traces of the pigment can still be seen. It is bordered by a beautiful ring of pigment. See Plate XXX for the pathology. The lesion in this case was due to a quite circumscribed syphilitic disease of the vessels. 210 Tab. 41. Fit:. 74. •ig. (3. PLATE XLII Fig. 76. Extensive So-called Chorioretinitis Disseminata with Scleroses of the Vessels of the Chorioid Fig. 77. So-called Chorioretinitis Disseminata with Scleroses of the Vessels of the Chorioid Fig. 76. Extensive So-called Chorioretinitis Disseminata with Scleroses of the Vessels of the Chorioid The fundus shows serious changes througliout its entire extent, so fur us it is depicted here, partly by jiatches of ilecoloratioii, partly by heaps of pigment. I'he papilla and the vessels of the retina are normal; the latter pass smoothly over the lesions, hence the inner layers of the retina are likewise normal, and the lesions must lie in the outer layers of the retina and in the chorioid ; they are changes in the pigment epithelium and scleroses of the vessels. The larger part of the fundus to the nasal side of the jiapilla approaches the normal, yet, even in this part, lumps of pigment and sheathings of the vessels can be seen. Not a normal vessel of the chorioid is visible any longer in the rest of the fundus ; above there are some vessels that are filled with blood, but even these are sheathed. Where the pigment epithelium between them has already been lost pure white places are to be seen, produced by the sclera covered with remnants of tissue. A disappearance of the pigment epithelium of the retina is the first requirement in order that these details of the sclera may become visible, but when the pigment leaves it settles else- where and gives rise to pictures that resemble this one. Of the three causes of disseminated chorioretinitis with vascular sclerosis, syphilis, arteriosclerosis and nephritis, the first was the agent in this case. Fig. 77. So-called Chorioretinitis Disseminata with Scleroses of the Vessels of the Chorioid This picture exhibits changes that are quite similar to those shown in the preceding one, so much so that a separate description is not needed (see page 182). The cause in this case was a nephritis gravidarum. The symptoms ap- peared chiefly in one eye during the first pregnancy and became much worse during the second. As the second eye was seriously affected in a third pregnancy premature labor was induced, after which both the albuminuria and the changes in the eye retrogressed. When the patient became pregnant a fourth time an abortion was induced at once. 212 Tab. 42. Fig. 76. Fig. 77. PLATE XLIII Fig. 78. Chorioretinitis Tuberculosa Fig. 78. Chorioretinitis Tuberculosa (See page 181^ This picture sliows tlie typical condition of a tuberculosis of the chorioid that is fresh in some places, old in others. The fresh tubercles cannot be seen, they make themselves manifest bv the effect they produce on the retina; for tlio little, circumscribed spots are islands of retinal oedema. It can be perceived that these are raised wherever a vessel of the retina passes over one; the vessel exhibits a wavy course at that place, as well as the loss of the light streak in the depressions, charac- teristic of changes of level. The oedematous places are also a little hazy. Part of the older places are marked by depigmentations, part by accumu- lations of pigment. The wreathlike appearance is produced by the confluence of various individual foci. An im})ortant point to be noted is that no vascular changes are to be seen in the picture. 314 Tab. 4». Fig. 78. PLATE XLIV Fig. 79. Chorioretinitis Tuberculosa Fig. 79. Chorioretinitis Tuberculosa (See page 181) Tliis picture is one of an old tuberculosis. The hritrht spots arc, almost without exception, produced by the confluence of individual tubercles. In the vicinity of these spots is to be seen a depigmentation that looks "as though a chemical fluid had been poured over them." The heaping of pigment in the vicinity is considerably less than in diseases of the chorioid that accom- pany sclerosis of the vessels. Pigment gradually migrates into the retina as it liecomes atrophic (compare with Plate XXX). The vessels of the retina and the papilla are normal. 216 Tab. 44. n-. 79. PLATE XLV Fig. 80. Healed Inflammatory (Tuberculous?) Spot In the Macula Fig. 81. Fundus of the Eye in Acute Miliary Tuberculosis Fig. 80. Healed Inflammatory (Tuberculous?) Spot in the Macula (Sec page 181) An inflammatory spot about twice as largo as the papilla liad formed in the macula of a girl 14 years old. Its etiology was obscure, but there were no signs of accjuired or lurcditary sypiiilis. ]V, 179 iilliiiininiirica, ^04< ilisseniiiKita, 179, 2\2 pignifiito.sa, 58, 99, l(i8, ITl, 184 sei'oiithiry, 175, 181 ])r()lit('r:n',s, 17;}, 18J .syiM]>.itlictic. 1J7, 118 svi'liilitic, .« (' .'Svjiliilis ■ confifiiital, 175, 18(i, 190, 191, 198 tuberculous, 179, -'U, -'Hi Ciliary vessels, 1()7 Cilio-retinal vessels, 33 Circulus arteriosus iri7 Cocain, 11 Coiobonia, see Chorioid Commotio retinae, 73 Connective tissue, proliferation of, in the diorioitl, 18J, )iJO in tlie retina, lOJ, 105, 131 in tile retinal vessels, 1U3, 105 ring, IS Contraction, concentric, 51 Conns in atro|iliic |>a]>illa, 51 inferior. 33, 39. 18 temporalis. 3:i, 31. H Cornea. o]>acities, 73, 170 reflexes of, 'J Cyanosis, 101 Cvsticercus, 81 Depiginentation of tlie <'liorioi(l, 168, 175 Detaclinient of the chorioid, 181 retina. 73. lU(i. 157. KiO alliuniinuric, 133. 1 10, 15-2 funnel-sha])eil, 153 gibbous, 15J, l&j tumor, 153, 163 Diabetes, 59, 73, 77, 79, 139, 134, 154 clianges in vessels in chorioioi)hysis, 81 Image, inverted, 3 upright, 8 Infectious diseases, 119 Influenza of retina, 119 Injuries, 33, 71 iirain. 81 elicn-ioid. 176, 183 commotio, retinal, see Commotio detachment, 151 oiitic nerve, 54, 63, 83 retina. 104, 118, 134, 151 ruj)ture of chorioid, 330 Interrujition of conductivity, 54 227 Intervasciilar spaces, 25, 28 Intoxications, 52, 59, 79 Iridocyclitis, 71 Iris, colol)onia, 179 Iritis, 71, 171 Keratitis parenchymatosa, 170, 175 Labor, 100, 118, 212 Lamina basalis, l(i7, 169 cribrosa, Ki, 21, (Hi elastica, l(i7, 109 supracborioidea, IfiT, 1G9 vasciilosa, 1()7, 169 vitrea, 167, 169 Lead, 59 79 Lens, opacity of, 73 Leucocytba?niia, 102, 10+, 118, 119 retinitis, 135, 150 Level, differences, 9, 102, lOl, 105, 106, 130, 152, 173, 181 Light, snbjective sensations of, 151 Lymph spaces of adventitia, 103 Macula, 26, 112 changes, 176, 20-1. arteriosclerotic, 127, 176, 204 myo]iic, see Myopia colobonia, 177 color, '25 coroniila, 55, 137 hemorrhage, 118 investigation, 7 oedema, 1+9 star, 130. 133, 138, U3 traumatic i>crforation, 120 Malaria, neuritis, 73 retinal hemorrhages, 119 Mediastinal tumors, 73 MeduUatcd nerve fibers, 35, 40, 48, 102, 128 Meiosis, 54 Meningitis, 73, 76, 77, 90 serosa, 81 syphilitic, 53, 76, 190, 19+ tiiberculous, 76, 218 retinitis, 138 Metamorphn]isia, 151, 181 Methyl alcohol. 59, 78 Micro|)bthalmos, 179 Miliary tuberculosis, 125 retinal hemorrhages. 119 Ilueller's supporting fibres. 130, 169 Multiple sclerosis, 52. 54, 59, 68, 79 Mydriasis. 11. 52, 76 Myelitis (neuritis), 73 Myopia, .35, etc., 44, etc., 105. 118, 181, 182, 206, etc. changes in macula, 176, 206 course of vessels, 25 detachment, 151 Naevus of retina, 138 Nephritis, see Albuminuria Nerve fibers, varicose thickening of the lavcr of, 129 Neuritic atrojiby of the optic nerve, seg Atro])hv Neuritis. 71, 86," 100. 120 albuminurica, 75. 76. 88, 134 arteriosclerotica, 77, 88 axialis. 78. 135 bilateral, 72, 75 Neuritis, course of, 74 diabetica. 70, 142 diffrrcMtial diagnosis, 73 etioi(»gy. 75 in otitis, see Otitis interstitial, 70 ojjtic, otogenous, 72, 77, 88 otogenous, 77, 88 retrobulbar, 58, 78 sympathetic, 78, 148 sy])liililic, 75, 86 tuberculous, 70, 86, 218 Neuroneuritis, see Neuritis and Retinitis Nicotin, 52, 59, 81 Nystagmus, 59, 179 Ocular muscles, paresis, 15+ CEdema of retina, see Retina O])hthalmoplegia, 54 Optic nerve, anatomy, 15 atro])hy. ,iei Atrophy colobonia, 33, 178 hemorrhages, 83 infiammation, see Neuritis injuries, 83 interrujition, 103 tubercle, 76, 83 tunuirs, 83 Optico-ciliarv vessels. 2.3. 57, 105 Orbit, absces's, 81 neuritis, 72, 77 tumor, 81, 100, 101 venous engorgement, 102 Otitis, neuritis, 72, 77, 90 dilatation of retinal vessels, 100 Otogenous neuritis, see Neuritis Oxycephalus. 54, 72 choked disk, 81 neuritis, 72 Pachymeningitis, 82 Papilla, development of connective tissue, 83 hemorrhages, 83 hy|)era'mia, 71 indistinct, 73 large. 17, 33 normal, 16, 17, 28 small. 17 Papillo-macularv bundles, 16, 59, 78 atrophy, 52," 59 Paralactic displacement. 9 Paralysis, 5+ Paresis of ocular muscles, 54, 59. 76 Pepper and salt fundus. 175 Perineuritis, 76 Peri]ia]iillarv atrophy of chorioid, see Chorioid Perspective dis])lacenicnt, 9 l'hoto|isias. 151 Phthisis bulbi. see Uctacbinent of chorioid, 181 Pigment of chorioid, 23 changes, 172. etc. degeneration of retina, see Chorio-retinitis entrance of retina, 58, 64, 8S. 131. 150. 210 eiutliclium, layer of 24, 112, 167, 169 rins:. 18 sjiots. 109 Pigmentation, sort, 172 Plethora, 100 Pneumonia, 101 neurit's. 72 PolMxtlia-Tuia. 101 Porcupine, eye of, 53 I'rejiMiiiH'y, 212 I'rogiiosi.s ill changes of retina ami ehorioid, 153 Pseudo-neuritis, 71 differential diagnosis, 73 Ptosis, 51 Pupilla, dilation, 10 innniil)ilily, ,j:i, 51, 59, 76 Purpura, retinal lieniorrliages, 119 Quinine, 59 Raliltit, 11, 234. HeHex light streak, 103 Keflex of retinal vessels, 105 Uefraction, determination of, 10 Uetina, anatomy, 11 1 atrophy, see Atroj)hy changes, jjosition of, 113 Jirognosis, 153 delacliment, see Detachment differential diagnosis, 119 diffuse opacities, IW fatty degeneration, 130, 133, 138 fibrinous exudates, 130, 1 Ki hemorrhages, 115, IKi, 122. 133, 138 intiltration with white hlood corjniscles, 150 injuries, 118, 121 oedema, 72, 73, 75, 7S, 8fi, 101, 102, 10«, 129, U9, 150, 178, 214. otitis, 77, 150 pigment invasion, see Migrating Pigment prognosis, 153 reflexes, 26, 104, 105, 128 ruptures, 119 tumors, 152 veins, pheboselerosis, 101 thrombosis, 81, 99, 101, 102, 103, 117, 122, 153 vessels, 22, 25, 55, 97, 113, 117, 122, 126, 152, 190, 202 acconipan\ing stripes, 57, B4, 75, 99, 102, 150, 156 aneurism, 102, 144 color, 102 contraction, 98 dilatation, 57, 73, 79, 92, 100, 117 dnuinution, 104 embolism, see Central Artery fluctuations in caliber, 99 glaucoma, see Glaucoma increase, 104 lime deposits, 103 lym]>h sjiaces, 103 new formations, 57, 101 obliteration, 57, 104, 129, 153, 190 phlebectasia, 102 jihvsiological differences, 99, 104, 208 pulsation, 23, 99 reflexes, 20, 103, 105 sclerosis, 55, 99, 102, 106, 153, 190, 202 thrombosis, see Retinal Veins tortuositv, 100, 105 Retinitis, alb'uminnrica, 34, 99, 131, 133, 138, etc. prognosis, 134, 154 ana?mica, 135 circinata, 134 definition of, 114 diabetica, 99, 135, 144. prognosis, 153 Retinitis, diffusa, 149 Icncirniica, 135, 150 jjiguuiitosa, see Chorioretinitis I)rolilera, 103, 129, 135, 136, 144 sei)tica, 125, 132 syphilitica, 135, 146, 156 Retraction crescent, 36 Rctriibnibar neuritis, 58 Rhinoceros, eye of, 53 Sdelis' lamj), 153 Scarlet fever, lU'Uritis, 72 (S'(7iirf(«n's sheath, 16 Scleractasia, 26, 181, 208, 223 Scleral ring, 18 \'essels, 222 Sclerosis of retinal vessels, see Retinal Vessels multiple, see Multiple Sclerosis Sclerotic vascular ]ilexus, 15 Sclerotico-chorioideal canal, 19, 35 Scotoma, central, 54, 59, 68, 77, 181 Scurvy, 119 Secondary glaucoma, 101 Sepsis, retinal hemorrhages, 119 white spots, 125 Sinus cavcrnoMis, 15, 82 thrombosis, neuritis, 77, 90 Small))<)x, neuritis, 72 Snuff fundus, 175, 198 .S)ihcnoidal sinus, 59, 79 Spots, l)laek, 114, 169, 174 white. 115, 125, 138, 169 Sta]ihvlonia, 55 posticum, 33, 37, 38, 46, 206 changes in chorioidal vessels, 35 veriini. 26, 174, 181. 208 Stijipled fundus, 24, 28 Strabismus, 179 .Stri])es, accompanying, 102 Supertracti(ui crescent, 19, 35, 44 Svmpathetic inflammation, chorioidal spots, 127, 148 neuritis, 78 Synchysis scintillans, 130 Synco|ie, 99 Syphilis, see Chorioretinitis, 53, 64, 73, 86, 117. 129, 150, 171, 180, 210, 212 atrophy, 53, 57, 76 changes in retinal vessels, 100, 122, 130, 153 choked disk. 81 congenital, 73, 76, 174, 186, 190-202 detachment. 152 gunuiia, see Ciunima neuritis. 72. 75, 86 retinal hemorrhages, 118, 119 retinitis. 135, 146, 149, 150, 156 proliferans, 129, 144 Tabes. 54, see Atrophy Technique, 3 Temporal detachment, see Atrophy of Optic Nerve Thrombosis of central vein 78, 99, 101. 103, 117, 122 Tortuosity of vessels. 25 Transverse gunshot wounds, 173. 182 Trunk, thrombosis of. 117 Tiilicrcle of ehorioid, 76, 130, 149, 179, 214 of brain. 81 of optic nerve. 76. 82, 86 229 Tumor, brain, see Brain chorioid, 15:?, 181 detachment, 151 intraocular, luO, 105 retina, 153 Typhoid, hemorrhages of retina, 119 neuritis, ~-2 retinitis, 133 Ulcus ventriculi, 100 Uraemia, 134 Varicose thickening of the laver of nerve fibers, l-'9 Vena centralis, thrombosis, see Thrombosis ophthalmica, 15 Venous pulse, 23, 106 Visual field, concentric, 54 loss of sectors, 52, 54 purple, 34 Vitreous, hemorrhage into, 118 opacities, 73 prognosis, 154 recurrent, 119 Weiss-Otto shadow ring, 26 Weiss' reflex ring, 36 Werlhoff's disease, retinal hemorrhages, 119 Wounds, transverse gunshot, 173, 1»3 Zinn's sclerotic vascular plexus, 15, 23, 44, 68, 168 Ill il li; 1,; ^ D 000 141 974 6