Technique of Eye Dissections

Part 1

Transcriber’s Notes

Italics text has been transcribed between underscores. Small capitals have been replaced with ALL CAPITALS.

More Transcriber’s Notes may be found at the end of this text.

The eye--it cannot choose but see.

--Wordsworth.

TECHNIQUE OF EYE DISSECTIONS

FREDERIC A. WOLL, Ph.D.,

Associate Professor, Department of Hygiene, College of the City of New York; Optometry Courses, Columbia University; Member of New York State Board of Examiners in Optometry; Honorary Member: American Optometric Association; State Societies--Alabama, California, Connecticut, Kentucky, Maine, Massachusetts, North Carolina, Rhode Island; Local Societies--Lehigh Valley Society of Optometrists, Mahoning Valley Optometrists’ Society, and Optometrists’ Club of Brooklyn.

SECOND EDITION

NEW YORK FREDERIC A. WOLL 1924

COPYRIGHT, 1914, BY FREDERIC A. WOLL Printed in the United States of America First Edition, July, 1914 Second Edition, April, 1924

SCHLUETER PRINTING CO., NEW YORK

DEDICATION

THIS LITTLE BOOK IS DEDICATED WITH AFFECTION AND ESTEEM TO MY FIRST TEACHER IN OPTICS, MY FRIEND FOR YEARS

ANDREW JAY CROSS

WHOSE RESEARCH IN THE FIELD OF APPLIED OPTICS HAS WON FOR HIM RECOGNITION AND HONOR

CONTENTS

PAGE

Preface 13

Introduction 17

Removal of Hyaloid Membrane with Contents and Attachments Intact 25

Canal of Petit, The 35

Interior of the Eye, The 38

Posterior Half, The 40

Optic Nerve, The 47

Anterior Half, The 49

Iris, The 51

Cornea, The 52

Part 2

Crystalline Lens, The 53

Choroid, The 62

Retina, The 74

Sagittal or Vertical Section of the Eye, The 86

Papilla, Puncta Lacrimalia, and Nasal Duct, The 92

Meibomian Glands and Ducts, The 96

Enucleation of the Orbital Contents, The 97

Ophthalmoscopic Examinations 106

Lacrimal Ducts, The 112

Lacrimal Gland, The 114

Capsule of Tenon, The 115

Superior Oblique Muscle and its Pulley 117

Other Extrinsic Muscles, The 118

Three Tunics of the Eye, the Hyaloid and its Attachments, The 120

ILLUSTRATIONS

PAGE

0. Brain showing eyes with muscles removed, optic nerves, and chiasm Frontispiece

1. Glassware and tools 22

2. The first cut 28

3. How the point of the scissors is kept away from the underlying tissues 29

4. Half of the sclerotic separated 30

5. Picking up the choroid 31

6. Emptying the eye of its contents 32

7. Isolated hyaloid, contents and attachments intact 33

8. Petit’s Canal 36

9. Cutting eye into anterior and posterior sections with safety-razor blade 39

10. Posterior half showing retinal vessels and choroid 40

11. Showing network of vitreous 42

Part 3

12. Tearing retina away from posterior half of eye 44

13. Posterior half of eye with retina removed 45

14. Excavated posterior half of eye 46

15. Split optic nerve 47

16. Ciliary processes and the lens 48

17. How to pull off vitreous 50

18. Processus Zonuloe 54

19. Onion-like layers of lens removed 56

20. Cross section of lens 57

21. Lenses showing the results of different kinds of treatment 60

22. Puncturing the cornea 63

23. Removing the cornea 64

24. How to separate the choroid from the sclerotic 65

25. Cutting away the separated sclerotic 67

26. Scraping the choroid free from the sclerotic 68

27. The isolated choroid 69

28. Inserting scalpel to loosen lens and cut through vitreous 70

29. Taking out lens and “core” of vitreous 71

30. Squeezing out remaining part of vitreous 72

31. Cutting through the iris 75

32. Cutting around the ciliary ring 76

33. Lens, iris, and part of vitreous removed 77

34. How to force blowpipe into the vitreous 78

35. Bulging out of vitreous caused by blowing air through glass blowpipe 79

36. Showing vitreous removed 80

37. Folding the retina by blowing air at it through blowpipe 81

38. Suspended retina. Sclerotic ready to be cut away 82

39. Showing sclerotic nearly all cut away 83

Part 4

40. Isolated retina 84

41. The beginning of the cutting of the eye for sagittal sections 87

42. Method of cutting through the crystalline lens 88

43. Cutting through cornea to complete the sagittal sections 89

44. Sagittal section enlarged 90

45. Part of calf’s head showing knitting needles inserted in puncta 93

46. Course of knitting needles showing the course of the canaliculi 94

47. Initial cuts to be made in the skin 98

48. First cut in bones of orbit 99

49. All the cuts to be made in bones of orbit 100

50. How to pry bone loose 101

51. Dissecting close to bones of orbit 102

52. Excavated orbit 103

53. Anterior view of enucleated eye 104

54. Side view of enucleated eye. All parts in situ 104

55. Enlarging pupil for ophthalmoscopic inspection 107

56. How to get rid of the pucker in the cornea 108

57. Window cut in the eye 110

58. Pins inserted in lacrimal ducts 112

59. Capsule of Tenon blown up 115

60. Showing the extrinsic muscles of the eye 118

61. Cutting through the iris 120

62. Scraping ciliary processes free. Choroid cut around ciliary ring 121

63. Cutting away choroid 122

64. Three tunics, hyaloid, and lens 123

PREFACE

The aim of this booklet is to present to the eye-specialist, the teacher, the student, and others interested in the study of the anatomy and physiology of the eye, some definite methods to follow in the dissection of that organ.

Most dissections of the eye are not made with the same degree of care and skill used in the dissections of other organs. In following the usual method of dissecting eyes, much of the important detail is lost. Often certain membranes are confounded with others, and wrongly demonstrated. Furthermore, an eye is merely divided by some demonstrators into an anterior and a posterior half, a very short time is spent by the students scrutinizing each half; then the text-book is turned to, and the anatomy is studied descriptively.

Part 5

Not enough time has been given to thoroughly dissecting all parts of the eye. As much time should be given as is necessary to bring out prominently all its parts. Other organs of the body are more thoroughly dissected, and, therefore, the student has better opportunity to gain a clearer comprehension and better understanding of the anatomy and physiology of those organs. Also, as much time should be given, proportionately, to the learning of the technique of the dissection of the eye as is given to the learning of the technique of dissecting other organs of the body.

Many now make a direct specialty of ministering to those suffering from errors of ocular refraction, ocular diseases, and ocular reflexes, and for those specialists, principally, this book is written. It is to fulfil its mission to them by acting as a guide and as a complement to the descriptive matter in the text-book. It is sent forth in the hope that it will tend to create more interest in the study of the practical anatomy of the eye. It is written with a desire to stimulate the ability to make careful and intelligent observation. It carries with it, as a final end, an earnest wish that it may, in some small way, be the means of opening up to the original researcher, a larger field for the further study of the most important of the senses--the eyesight.

Most of the dissections explained in the following pages are original; some, however, are only revisions of old methods.

This opportunity is taken to acknowledge the many helpful suggestions that were made by Dr. Ivin Sickels, of the College of the City of New York, and by the late Dr. Edward C. Spitzka, of New York. Thanks are due Mr. E. F. Howes, of Messrs. Swift & Co., for furnishing the necessary supply of beef eyes; to Messrs. Lee & Beach, photographers, of New York, for their painstaking efforts in producing good photographs of the actual dissections; and to Schlueter Printing Company, of New York, for their many courtesies and interest in the production of the book.

FREDERIC A. WOLL.

New York, July 21, 1914.

INTRODUCTION

In eye dissections it is unnecessary to have either a large equipment of instruments or a special room. To have a laboratory at one’s disposal is but a small added convenience. Not to have it, is no serious hindrance. The work may be carried on and successfully done in one’s office or in the home, as well as in class-room or laboratory. If it is true that the atmosphere of a laboratory adds zeal to the efforts of a worker, but there is no laboratory available, then reverse the order; let the zeal of the worker add to the atmosphere of the place in which he is doing his work.

Two things, among others to be mentioned later, are essential; a table of convenient height, and a good light, natural or artificial. Both are but modest needs. Compared with other dissections, there will be found an absence of offensive odors. Neither are there any repulsive sensations experienced. Such experiences are quite common when making other kinds of dissections. This work is clean and attractive. Indeed, one may even develop a rather keen sense of the æsthetic. Many of the various parts of the eye, when separated and properly preserved, then viewed and inspected, are bound to bring forth exclamations of appreciation and wonderment. One can then better understand the statement: “When Nature perfected the first eye she took a day off so she could admire the result of her finest piece of handiwork.”

Continue reading Technique of Eye Dissections free in the Wunder reader →