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Experimental Production of Detachment of the Retina
EXPERIMENTAL PRODUCTION OF DETACHMENT OF T H E RETINA HERMAN W E I S S ,
M.D.
AND J O H N N. EVANS, BROOKLYN
M.D.
Placing of a tight ligature about the optic nerve produced edema of the nerve head, peripapillary detachment of the retina and in some cases balloon-like detachments. From the research department of the Brooklyn Eye and Ear Hospital.
through the openings so as to carry the ligature around the posterior third of the globe in the form of a loop, the ends of which ultimately protruded through the original conjunctival incision. The large venous sinus back of the globe was slightly injured during manipula tion but the bleeding quickly ceased. The eyegrounds were then examined, there being no apparent difference be tween the two eyes. The vessels and margins were normal. The margins of the nerve head were seen with a —2 sphere. The nerve was then compressed with a single tie and without much pressure. (We assumed that this liga ture included the optic nerve and its immediately adjacent structures—later this was verified by histologic studies.) There was an almost instantaneous change in the appearance of the papilla. The lower margin assumed a shelf-like appearance, protruding directly out into the vitreous. At the end of the first minute, the dome of this shelf was seen with a plus 5 sphere. This apparently was a peripapillary detachment of the retina involving first the lower margin of the nerve head and then gradually ex tending around either side. The suture was then drawn tighter and there was a rapid production of edema which com pletely obscured all the margins of the nerve head. The detachment then ap On August 22, 1933, a rabbit was in parently increased in height and area jected intraperitoneally with 2 cc. of a until the dome was seen with a plus mixture containing 70 percent ether, 30 12 sphere. The animal died about two percent albolene, and 10 gms. of chlore- hours after the operation and the eye tone to 100 cc. of this mixture. Deep was removed for histologic study. anesthesia developed in 20 minutes. The There were certain modifications of lids were then separated with the fin gers and a suture was passed through the above procedure. These were: the superior oblique muscle which 1. Use of #3 surgical black silk for served for traction. Openings were then ligation of the nerve when it was de made in the conjunctival fornix and in sired to produce the "shelf" like detach Tenon's capsule above. An aneurysm ment involving the lower peripapillary needle threaded with 18 lb. test braided area. Japanese silk fishing line was passed 2. Use of 18 lb. test braided, Japan627
In the Spring of 1933, we attempted experimentally to reproduce variations in ocular tension in accordance with the theory suggested by Salzmann 1 that a certain type of obstruction to the return flow through the central vein was re sponsible for some of the phenomena in glaucoma. Accordingly, as a prelim inary step, we attempted to place liga tures around the optic nerves in rab bits' eyes to simulate conditions postu lated by this theory. The ensuing events were so bizarre and so different from anticipated results, that we hasten to record them as they occurred, insofar as they might possibly offer new ma terial for speculation as to the pathogenesis of such conditions as detach ment of the retina, choked disk and ret inal edema. The fact that the same pro cedure was carried out with similar re sults in a patient whose eye was enu cleated for sarcoma of the choroid, makes more intimate the relation of this experimental data to the clinical pic ture. Approximately thirty rabbits were used. A detailed record was kept of sev enteen rabbits. Both eyes were carefully examined for disease or anomaly, one eye being reserved as a control while the other served for experimentation. The following summaried protocol will serve to illustrate the technic:
628
HERMAN WEISS AND JOHN N. EVANS
ese silk fishing line to produce wide spread retinal detachment. 3. Passing the suture around the nerve was sometimes performed by multiple punctures of the conjunctiva and repeated rethreading of the aneurysm needle, while at other times it was possible to pass the suture en tirely about the nerve and withdraw it from the same conjunctival open ing through which it had entered. 4. When it was desired to maintain pressure about the nerve temporarily, the standard snare for enucleation was used—the wire however being replaced
Fig. 1. (Weiss and Evans). The above photomicrograph is from one of our prep arations in which the ophthalmoscopic pic ture was that of an extensive "balloon de tachment." The fluid beneath the retinal folds appears to be a transudate.
by the above silk. After the suture had been on the required length of time, the pressure of the snare was released. This permitted the retina to reassume grad ually its normal position, (at times in twenty minutes). 5. In order to study the effects of ligation over varying periods of time, we terminated the animals or released the ligature at intervals varying from a few minutes to several weeks. The optimum time seemed to be in the neighborhood on one hour. It is our impression from our oph thalmoscopic studies, and also the im 1
pression of numerous ophthalmologists to whom we have demonstrated the phenomena, that the various stages of this picture can be interpreted as (1) edema of the nerve head, and (2) of the adjacent retina; (3) peripapillary de tachment of the retina; (4) spreading of edema and detachment mostly below and in the retinal vessel streak; (5) complete balloon detachment of the ret ina which involved in its last stages all the retina. Note: In our series of rabbits, we were able to produce this complete balooning in onlyfour instances. Albino rabbits seemed de cidedly the best subjects.
The question naturally arose as to the nature of the fluid beneath the detach ment. The most obvious answer to this question was to collect some of the fluid. This was done in one case of marked ballooning and found to be a clear, watery fluid which did not coagulate on standing, and which contained no flocculi. It did however produce flocculation on boiling. More elaborate studies of this fluid are under way. The next question of importance was to determine by histologic study whether the picture had its origin in a detachment or in simple edema of the retina. In this we encountered more dif ficulty than we expected because of un satisfactory fixation, as the fluid was apparently extracted in the hardening process. Various forms of fixation are being studied at this time and a report on histologic findings is reserved for a later note. This note is submitted at this time because of the interest in surgical treat ment of retinal detachment, the fact that the technic is applicable to human eyes about to be enucleated for various reasons, and the hope that application of the method herein outlined—both in the laboratory animal and in the hu man eye—will aid in an understanding of the mechanism of similar clinical pic tures and in the adaption of therapeutic measures for their control.
Reference
Salzmann, Prof. Dr. Maximilian. Glaucoma and retinal circulation. (Abhandlungen aus der Augenheilkunde und Ihren Grenzgebieten. Edited by C. Behr and J. Meller, Hamburg and Vienna. Part IS. (monograph).
M.D.
AND J O H N N. EVANS, BROOKLYN
M.D.
Placing of a tight ligature about the optic nerve produced edema of the nerve head, peripapillary detachment of the retina and in some cases balloon-like detachments. From the research department of the Brooklyn Eye and Ear Hospital.
through the openings so as to carry the ligature around the posterior third of the globe in the form of a loop, the ends of which ultimately protruded through the original conjunctival incision. The large venous sinus back of the globe was slightly injured during manipula tion but the bleeding quickly ceased. The eyegrounds were then examined, there being no apparent difference be tween the two eyes. The vessels and margins were normal. The margins of the nerve head were seen with a —2 sphere. The nerve was then compressed with a single tie and without much pressure. (We assumed that this liga ture included the optic nerve and its immediately adjacent structures—later this was verified by histologic studies.) There was an almost instantaneous change in the appearance of the papilla. The lower margin assumed a shelf-like appearance, protruding directly out into the vitreous. At the end of the first minute, the dome of this shelf was seen with a plus 5 sphere. This apparently was a peripapillary detachment of the retina involving first the lower margin of the nerve head and then gradually ex tending around either side. The suture was then drawn tighter and there was a rapid production of edema which com pletely obscured all the margins of the nerve head. The detachment then ap On August 22, 1933, a rabbit was in parently increased in height and area jected intraperitoneally with 2 cc. of a until the dome was seen with a plus mixture containing 70 percent ether, 30 12 sphere. The animal died about two percent albolene, and 10 gms. of chlore- hours after the operation and the eye tone to 100 cc. of this mixture. Deep was removed for histologic study. anesthesia developed in 20 minutes. The There were certain modifications of lids were then separated with the fin gers and a suture was passed through the above procedure. These were: the superior oblique muscle which 1. Use of #3 surgical black silk for served for traction. Openings were then ligation of the nerve when it was de made in the conjunctival fornix and in sired to produce the "shelf" like detach Tenon's capsule above. An aneurysm ment involving the lower peripapillary needle threaded with 18 lb. test braided area. Japanese silk fishing line was passed 2. Use of 18 lb. test braided, Japan627
In the Spring of 1933, we attempted experimentally to reproduce variations in ocular tension in accordance with the theory suggested by Salzmann 1 that a certain type of obstruction to the return flow through the central vein was re sponsible for some of the phenomena in glaucoma. Accordingly, as a prelim inary step, we attempted to place liga tures around the optic nerves in rab bits' eyes to simulate conditions postu lated by this theory. The ensuing events were so bizarre and so different from anticipated results, that we hasten to record them as they occurred, insofar as they might possibly offer new ma terial for speculation as to the pathogenesis of such conditions as detach ment of the retina, choked disk and ret inal edema. The fact that the same pro cedure was carried out with similar re sults in a patient whose eye was enu cleated for sarcoma of the choroid, makes more intimate the relation of this experimental data to the clinical pic ture. Approximately thirty rabbits were used. A detailed record was kept of sev enteen rabbits. Both eyes were carefully examined for disease or anomaly, one eye being reserved as a control while the other served for experimentation. The following summaried protocol will serve to illustrate the technic:
628
HERMAN WEISS AND JOHN N. EVANS
ese silk fishing line to produce wide spread retinal detachment. 3. Passing the suture around the nerve was sometimes performed by multiple punctures of the conjunctiva and repeated rethreading of the aneurysm needle, while at other times it was possible to pass the suture en tirely about the nerve and withdraw it from the same conjunctival open ing through which it had entered. 4. When it was desired to maintain pressure about the nerve temporarily, the standard snare for enucleation was used—the wire however being replaced
Fig. 1. (Weiss and Evans). The above photomicrograph is from one of our prep arations in which the ophthalmoscopic pic ture was that of an extensive "balloon de tachment." The fluid beneath the retinal folds appears to be a transudate.
by the above silk. After the suture had been on the required length of time, the pressure of the snare was released. This permitted the retina to reassume grad ually its normal position, (at times in twenty minutes). 5. In order to study the effects of ligation over varying periods of time, we terminated the animals or released the ligature at intervals varying from a few minutes to several weeks. The optimum time seemed to be in the neighborhood on one hour. It is our impression from our oph thalmoscopic studies, and also the im 1
pression of numerous ophthalmologists to whom we have demonstrated the phenomena, that the various stages of this picture can be interpreted as (1) edema of the nerve head, and (2) of the adjacent retina; (3) peripapillary de tachment of the retina; (4) spreading of edema and detachment mostly below and in the retinal vessel streak; (5) complete balloon detachment of the ret ina which involved in its last stages all the retina. Note: In our series of rabbits, we were able to produce this complete balooning in onlyfour instances. Albino rabbits seemed de cidedly the best subjects.
The question naturally arose as to the nature of the fluid beneath the detach ment. The most obvious answer to this question was to collect some of the fluid. This was done in one case of marked ballooning and found to be a clear, watery fluid which did not coagulate on standing, and which contained no flocculi. It did however produce flocculation on boiling. More elaborate studies of this fluid are under way. The next question of importance was to determine by histologic study whether the picture had its origin in a detachment or in simple edema of the retina. In this we encountered more dif ficulty than we expected because of un satisfactory fixation, as the fluid was apparently extracted in the hardening process. Various forms of fixation are being studied at this time and a report on histologic findings is reserved for a later note. This note is submitted at this time because of the interest in surgical treat ment of retinal detachment, the fact that the technic is applicable to human eyes about to be enucleated for various reasons, and the hope that application of the method herein outlined—both in the laboratory animal and in the hu man eye—will aid in an understanding of the mechanism of similar clinical pic tures and in the adaption of therapeutic measures for their control.
Reference
Salzmann, Prof. Dr. Maximilian. Glaucoma and retinal circulation. (Abhandlungen aus der Augenheilkunde und Ihren Grenzgebieten. Edited by C. Behr and J. Meller, Hamburg and Vienna. Part IS. (monograph).