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Memphis Eye, Ear, Nose and Throat Society
SOCIETY PROCEEDINGS EDITED
BY
DONA
MEMPHIS EYE, EAR, N O S E A N D T H R O A T SOCIETY March 1 4 , 1 9 6 1 BILATERAL
HETEROCHROMIC
CYCLITIS
D R . A L I C E R. D E U T S C H presented Mr. H. R. who was seen for the first time in May, 1 9 5 9 , when he was 2 0 years of age. He gave the history of having had some blurring of vision for severeal months. A prescription for drops was given to him when he consulted his local physician at that time. The drops, which proved to be cortisone, had been used ever since.
On examination both eyes were without injection. The posterior surface of both corneas was studded with numerous small grayish white precipitates. The irises were blue and showed a delicate structure and a diminution of the radial markings. There was a mild flare in the anterior chambers. Fine dustlike opacities were located immediately under the posterior capsule of both lenses. A mild color-chagrin was also present. The fundi were subalbinotic. No choroidal lesions could be seen. Physical examination was entirely negative including old tuberculin tests and tests for toxoplasmosis and histoplasmosis. The corrected vision was 2 0 / 2 0 in each eye and the intraocular pressure was normal. Mr. H. R. did not return for a follow-up examination until December, 1 9 6 0 , at which time he complained of impairment of vision. Again both eyes showed no external signs of inflammation. The posterior corneal surface was still studded with keratic precipitates with fine grayish threads between them. The irises had lost their normal architecture, the pupillary margin appeared moth eaten and some dilated vessels were visible in the chamber angle on gonioscopy. The pupils dilated easily. Both lenses showed a typical
)
J.
LYLE,
M.D.
complicated posterior cortical cataract. No fundus lesions were visible and apparently no lesions were present over the pars plana of the ciliary body which, however, was difficult to see so that localized lesions could have been missed. The corrected vision was 2 0 / 4 0 J 4 , in each eye.
The clinical impression of the irises in both eyes, the appearance of small vascular twigs in the chamber angle of both eyes, the lack of posterior synechia and the complicated cataracts resembled the clinical picture of Fuchs' heterochromic cyclitis, a rare monocular eye disease of obscure etiology, which seldom has been observed in both eyes. Some authors refer the iris and ciliary-body anomalies to a disturbance of the cervical sympathetic nerve supply. Others considered it a development of a nonspecific low-grade uveitis and not a specific entity. Secondary cataracts, frequently seen, have mostly been removed without complication and good visual results ; certainly with a much better prognosis than the complicated cataracts with some other types of uveitis. Differential diagnostic tests for this specific cyclitis have been described. French authors found a specific globulin in the anterior chamber fluid; others believe a localized bleeding in the anterior chamber after puncture to be significant. Those and other tests, however, are very difficult to interpret. Mr. H. R. is 2 2 years of age, a chemical engineer, whose professional skill depends on good eyesight. The prognosis of heterochromic cyclitis after cataract extraction is good and this disease should not preclude a continuation of his profession. The only complication, which is, however, not common, is secondary glaucoma. A s the future of eyes with complicated cataracts of other causes is uncertain, complete evaluation and possible advise for a change of profession might be indicated.
SOCIETY COMPLICATIONS DR.
PHILIP
FROM
PROCEEDINGS
TREPHINATION
MERIWETHER
LEWIS
re-
ported a case having some interesting complications after trephination. A white woman, aged 80 years, had advanced chronic open-angle glaucoma with incipient cataracts in both eyes when first seen in March, 1960. The tension remained high, 40 mm. Hg, O.U., and the fields continued to deteriorate in spite of strong miotics, epinephrine bitartrate and carbonic anhydrase inhibitors. In spite of her age, trephination was selected as the operation of choice because a definite hypotony was desired. The trephinations were done below in the 5-o'clock meridian, so as to preserve the upper limbus region for cataract extraction later. The left eye did well at first but the right had a flat anterior chamber due to a leaking flap. Air was injected into the anterior chamber and the flap was resutured on the fifth postoperative day. The conjunctiva had become quite necrotic so that it tore at each suture hole. N o healing occurred and the chamber again became flat. The anterior chamber was reinjected with air and the flap repaired again, but the wound continued to leak and the chamber became flat. On the 14th postoperative day, a thick flap of Tenon's capsule and conjunctiva was dissected down into the lower fornix so that it could be pulled up easily over the limbus. It was fastened securely to the lower (denuded) cornea with 6-0 silk mattress sutures. The anterior chamber was reinjected with air. A s the air absorbed, the anterior chamber became shallow again. Dr. Rychener, who saw the patient in consultation, suggested giving Diamox, which was done. Apparently this was helpful. The anterior chamber reformed and so remained. A s it was impossible to dilate the pupil while the chamber was flat some posterior synechias formed and vision decreased because of increased lens clouding. The tension gradually rose so that miotics and Diamox are necessary. The cause of failure of this operation was a leaking flap, which once more illustrates
465
the extreme care with which these flaps must be prepared and sutured. The left eye, which had done beautifully in the hospital, showed a rise of tension from a hypotony of 6.0 mm. H g to a hypertony of 38 mm. H g five weeks after operation. This was obviously due to the fact that the filtering bleb had become quite small. The trephine opening was normal in appearance. After topical anesthesia with pontocaine an injection of procaine with adrenalin was given lateral to the bleb. The procedure described by McCulloch was then performed. This procedure is important enough to describe and I, therefore, quote directly from McCulloch's article (Tr. Canad. Ophth. S o c , 1958). " A thin cataract knife is entered in the conjunctiva, approximately 10 mm. lateral to the bleb. The knife is passed through the area of conjunctival infiltration into the bleb, across the bleb and out the other side. Care is taken that the tip of the knife does not come out through the conjunctival epithelium but remains deep in the subconjunctival connective tissue. Then, by a sawing movement, the knife is carried upward through the bleb and up under the conjunctival epithelium above. Finally, when the bleb has been incised widely under the conjunctiva, the knife is carefully withdrawn through the small opening where it entered." Immediately, fluid was seen to flow under the conjunctiva and the tension fell so that the eye became quite soft. This procedure was partially successful in that it caused wider filtration and a lowering of tension. However, the bleb has become smaller and it is necessary to give small doses of Diamox three times daily and use miotics regularly in order to control the tension. Slides showing both eyes and illustrating McCulloch's procedure were shown. INTERMITTENT
MONOCULAR
DIPLOPIA
DR. ALICE R. D E U T S C H presented the case of Mrs. H. M. D., aged 56 years, who
466
SOCIETY
PROCEEDINGS
was seen for the first time in October, 1952. At this time the eye findings were essentially normal. She was fitted with her first pair of bifocal lenses which she wore without any discomfort. She was seen again in August, 1955, when she needed a change in glasses. Her corrected vision equalled 2 0 / 2 0 J 1 in each eye. No abnormalities were seen. The intraocular pressure was normal. She returned in February, 1959, complaining of blurred vision, especially for close. The anterior segment of each eye was normal. Slitlamp examination of the lenses disclosed a pronounced outline of the anterior surface of the adult nucleus, several cystoid spaces and vacuoles in the anterior cortex, as well as fine opacities under the posterior capsule of each lens. Ophthalmoscopy showed considerable beading of the retinal arteries and some sclerosis of the choroidal vessels. The macular region did not reveal any obvious pathology (Hrubylens). Her corrected vision ( O . D . + 1 . 2 5 D . sph.; O.S., + 1 . 2 5 D . sph., add 2.0D.) still equalled 2 0 / 2 0 and J l . Maddox rod test for distance showed Es. 2 Δ and no hyperphoria ; for close she had an Ex. 20 Δ and no hyperphoria. (She never had more than 6 Δ Ex. previously.) The intraocular pressure equalled 17.3 mm. Hg, O.U. She received a prescription for new glasses. These were not satisfactory for work as an accountant, as the figures doubled up. The same happened at home when she wanted to read. Weekends, however, she could read without discomfort. In view of the pronounced exophoria for close, clip-on prisms 3 Δ O.U. base-in were advised. These prisms made it easier for her to work but she still saw double images on week days, and now, not only at her desk, but also for distance. Whenever she drove home after work, road markings, headlights and traffic lights doubled up. She had the same diplopia with each eye separately and occasionally she saw three or four lights. It was not possible to provoke a diplopia at the office as the examinations always were made on Saturdays when she was not work-
ing. Red-light tests, the Lancaster tests, and fixation fields were normal. There was no metamorphopsia on the Amsler test. The tests were repeated with both pupils dilated and were again negative. The monocular diplopia tentatively was referred to the lens opacities, assuming that these opacities might be more noticeable over the glare of white paper on her desk. She was advised to use one-percent pilocarpine, hoping that this might take the offending lens opacities out of her field. She was asked to have a physical examination. The physical examination was negative except for a mild chronic gall-bladder disease. Pilocarpine gave very little relief. Mrs. D. was finally persuaded that she should be seen one evening after office hours so that the double images could be demonstrated. During this last evening examination a vertical diplopia was found in each eye. The two images were about two inches apart when checked at 20 ft. and approached each other some when coming closer but never became exactly one. Looking straight ahead the images of the two eyes covered each other completely. When shifting the gaze to the right or left, she mostly saw four lights. The size of the pupils was unchanged, and the refraction was the same, eliminating the possibility of a tension miosis and/or spastic myopia. Monocular diplopia has been referred to three main causes: Group I includes abnoimalities in the eye itself, irregularities in the cornea, pupil and lens, as well as specific diseases of the retina. Group II relates to projectional monocular diplopia which might occur in two ways : ( a ) a single retinal image is given two associations of direction, an innate normal projection and an acquired abnormal projection, depending on the development of abnormal correspondences ; ( b ) the image seen by an eccentric retinal point is brought into consciousness simultaneously with the macular image. This type of diplopia often is seen in connection with and treatment of amblyopia and squints.
SOCIETY
PROCEEDINGS
Group I I I refers to central monocular diplopia, a very rare condition. It might occur in lesions of the calcarine fissure. A new central functioning center or Pseudofovea may be established in the surviving part of the field. If this shift is incomplete, double vision may result. In cases of paresis of the extraocular muscles together with gross cerebral lesions, diplopia and secondary correspondence may develop. This phenomenon is probably caused by cerebral dissociation involving the independent activity of areas of the central cortex which normally act in association to produce a single sensory impression. Cases of this type have been described as occurring in various intracranial diseases. Monocular diplopia without manifest paralysis of any external eye muscle has been observed in the course of encephalitis, basal meningitis, multiple sclerosis and so forth. The same interpretation has been attempted to explain monocular diplopia of hysteria and functional disorders. Shift of spatial localization, namely, double vision of central origin may occur as a result of the acquirement of a double spatial conception in a damaged cortex. This most disagreeable condition is very obstinate and does not yield easily to any treatment.
467
they do, the vessels are secondary and do not resemble the normal retinal vascular pattern. Occlusion of one of the major arteries of the retina leads to marked edema of the retina which can be mistaken for detachment. Choroidal detachment, which may follow intraocular surgery, uveitis, or be spontaneous, can be differentiated from retinal detachment by the following points : 1. Choroidal detachments begin in the periphery and the ora serrata is clearly visible without pressure, since the choroidal detachment is pressing the retina inward. 2. The choroidal detachment is smooth with no folds. 3. The color of a choroidal detachment is darker than that of a retinal detachment. 4. Choroidal detachments are limited by the vortex ampullae. A cyclitic membrane, which has vessels, accompanying uveitis may resemble a retinal detachment. Cyclitic membranes usually begin inferiorly and the vascular pattern does not conform to the usual retinal pattern. Tumors of the choroid frequently are mistaken for detachment of the retina. Metastatic carcinoma tends to involve the posterior pole of the eye and results in a flat elevation of the choroid.
Schisis of the retina occurs in two forms: ( 1 ) a juvenile form which is rare and primarily involves young men who are subject to recurrent vitreous hemorrhages, and ( 2 ) the more common type known as the senile NEW ENGLAND type. Schisis can be differentiated from retOPHTHALMOLOGICAL inal detachment since the internal surface is SOCIETY smooth without folds, the vessels are frequently obliterated, there is a frosted apApril 26, 1961 pearance of the internal surface of the retD A V I D G. C O G A N , M.D., presiding ina and the field defects resulting from this condition have a steep edge. DIFFERENTIAL DIAGNOSIS OF RETINAL DETACHMENT A proliferating membrane in the vitreous due, for example, to diabetes can be conDR. ROBERT J . B R O C K H U R S T : A turbid vitreous from whatever cause can lead to a fused with retinal detachment A white flat mistaken diagnosis of retinal detachment membrane in the lower portion of the vitresince the choroidal pattern is obliterated. A ous may be the result of old hemorrhage in membrane in the vitreous may also be con- the vitreous and can be confused with retinal fused with a retinal detachment but these detachment. It is important to diagnose correctly semembranes do not have blood vessels or, if Ralph S. Hamilton, Secretary, Eye Section.
BY
DONA
MEMPHIS EYE, EAR, N O S E A N D T H R O A T SOCIETY March 1 4 , 1 9 6 1 BILATERAL
HETEROCHROMIC
CYCLITIS
D R . A L I C E R. D E U T S C H presented Mr. H. R. who was seen for the first time in May, 1 9 5 9 , when he was 2 0 years of age. He gave the history of having had some blurring of vision for severeal months. A prescription for drops was given to him when he consulted his local physician at that time. The drops, which proved to be cortisone, had been used ever since.
On examination both eyes were without injection. The posterior surface of both corneas was studded with numerous small grayish white precipitates. The irises were blue and showed a delicate structure and a diminution of the radial markings. There was a mild flare in the anterior chambers. Fine dustlike opacities were located immediately under the posterior capsule of both lenses. A mild color-chagrin was also present. The fundi were subalbinotic. No choroidal lesions could be seen. Physical examination was entirely negative including old tuberculin tests and tests for toxoplasmosis and histoplasmosis. The corrected vision was 2 0 / 2 0 in each eye and the intraocular pressure was normal. Mr. H. R. did not return for a follow-up examination until December, 1 9 6 0 , at which time he complained of impairment of vision. Again both eyes showed no external signs of inflammation. The posterior corneal surface was still studded with keratic precipitates with fine grayish threads between them. The irises had lost their normal architecture, the pupillary margin appeared moth eaten and some dilated vessels were visible in the chamber angle on gonioscopy. The pupils dilated easily. Both lenses showed a typical
)
J.
LYLE,
M.D.
complicated posterior cortical cataract. No fundus lesions were visible and apparently no lesions were present over the pars plana of the ciliary body which, however, was difficult to see so that localized lesions could have been missed. The corrected vision was 2 0 / 4 0 J 4 , in each eye.
The clinical impression of the irises in both eyes, the appearance of small vascular twigs in the chamber angle of both eyes, the lack of posterior synechia and the complicated cataracts resembled the clinical picture of Fuchs' heterochromic cyclitis, a rare monocular eye disease of obscure etiology, which seldom has been observed in both eyes. Some authors refer the iris and ciliary-body anomalies to a disturbance of the cervical sympathetic nerve supply. Others considered it a development of a nonspecific low-grade uveitis and not a specific entity. Secondary cataracts, frequently seen, have mostly been removed without complication and good visual results ; certainly with a much better prognosis than the complicated cataracts with some other types of uveitis. Differential diagnostic tests for this specific cyclitis have been described. French authors found a specific globulin in the anterior chamber fluid; others believe a localized bleeding in the anterior chamber after puncture to be significant. Those and other tests, however, are very difficult to interpret. Mr. H. R. is 2 2 years of age, a chemical engineer, whose professional skill depends on good eyesight. The prognosis of heterochromic cyclitis after cataract extraction is good and this disease should not preclude a continuation of his profession. The only complication, which is, however, not common, is secondary glaucoma. A s the future of eyes with complicated cataracts of other causes is uncertain, complete evaluation and possible advise for a change of profession might be indicated.
SOCIETY COMPLICATIONS DR.
PHILIP
FROM
PROCEEDINGS
TREPHINATION
MERIWETHER
LEWIS
re-
ported a case having some interesting complications after trephination. A white woman, aged 80 years, had advanced chronic open-angle glaucoma with incipient cataracts in both eyes when first seen in March, 1960. The tension remained high, 40 mm. Hg, O.U., and the fields continued to deteriorate in spite of strong miotics, epinephrine bitartrate and carbonic anhydrase inhibitors. In spite of her age, trephination was selected as the operation of choice because a definite hypotony was desired. The trephinations were done below in the 5-o'clock meridian, so as to preserve the upper limbus region for cataract extraction later. The left eye did well at first but the right had a flat anterior chamber due to a leaking flap. Air was injected into the anterior chamber and the flap was resutured on the fifth postoperative day. The conjunctiva had become quite necrotic so that it tore at each suture hole. N o healing occurred and the chamber again became flat. The anterior chamber was reinjected with air and the flap repaired again, but the wound continued to leak and the chamber became flat. On the 14th postoperative day, a thick flap of Tenon's capsule and conjunctiva was dissected down into the lower fornix so that it could be pulled up easily over the limbus. It was fastened securely to the lower (denuded) cornea with 6-0 silk mattress sutures. The anterior chamber was reinjected with air. A s the air absorbed, the anterior chamber became shallow again. Dr. Rychener, who saw the patient in consultation, suggested giving Diamox, which was done. Apparently this was helpful. The anterior chamber reformed and so remained. A s it was impossible to dilate the pupil while the chamber was flat some posterior synechias formed and vision decreased because of increased lens clouding. The tension gradually rose so that miotics and Diamox are necessary. The cause of failure of this operation was a leaking flap, which once more illustrates
465
the extreme care with which these flaps must be prepared and sutured. The left eye, which had done beautifully in the hospital, showed a rise of tension from a hypotony of 6.0 mm. H g to a hypertony of 38 mm. H g five weeks after operation. This was obviously due to the fact that the filtering bleb had become quite small. The trephine opening was normal in appearance. After topical anesthesia with pontocaine an injection of procaine with adrenalin was given lateral to the bleb. The procedure described by McCulloch was then performed. This procedure is important enough to describe and I, therefore, quote directly from McCulloch's article (Tr. Canad. Ophth. S o c , 1958). " A thin cataract knife is entered in the conjunctiva, approximately 10 mm. lateral to the bleb. The knife is passed through the area of conjunctival infiltration into the bleb, across the bleb and out the other side. Care is taken that the tip of the knife does not come out through the conjunctival epithelium but remains deep in the subconjunctival connective tissue. Then, by a sawing movement, the knife is carried upward through the bleb and up under the conjunctival epithelium above. Finally, when the bleb has been incised widely under the conjunctiva, the knife is carefully withdrawn through the small opening where it entered." Immediately, fluid was seen to flow under the conjunctiva and the tension fell so that the eye became quite soft. This procedure was partially successful in that it caused wider filtration and a lowering of tension. However, the bleb has become smaller and it is necessary to give small doses of Diamox three times daily and use miotics regularly in order to control the tension. Slides showing both eyes and illustrating McCulloch's procedure were shown. INTERMITTENT
MONOCULAR
DIPLOPIA
DR. ALICE R. D E U T S C H presented the case of Mrs. H. M. D., aged 56 years, who
466
SOCIETY
PROCEEDINGS
was seen for the first time in October, 1952. At this time the eye findings were essentially normal. She was fitted with her first pair of bifocal lenses which she wore without any discomfort. She was seen again in August, 1955, when she needed a change in glasses. Her corrected vision equalled 2 0 / 2 0 J 1 in each eye. No abnormalities were seen. The intraocular pressure was normal. She returned in February, 1959, complaining of blurred vision, especially for close. The anterior segment of each eye was normal. Slitlamp examination of the lenses disclosed a pronounced outline of the anterior surface of the adult nucleus, several cystoid spaces and vacuoles in the anterior cortex, as well as fine opacities under the posterior capsule of each lens. Ophthalmoscopy showed considerable beading of the retinal arteries and some sclerosis of the choroidal vessels. The macular region did not reveal any obvious pathology (Hrubylens). Her corrected vision ( O . D . + 1 . 2 5 D . sph.; O.S., + 1 . 2 5 D . sph., add 2.0D.) still equalled 2 0 / 2 0 and J l . Maddox rod test for distance showed Es. 2 Δ and no hyperphoria ; for close she had an Ex. 20 Δ and no hyperphoria. (She never had more than 6 Δ Ex. previously.) The intraocular pressure equalled 17.3 mm. Hg, O.U. She received a prescription for new glasses. These were not satisfactory for work as an accountant, as the figures doubled up. The same happened at home when she wanted to read. Weekends, however, she could read without discomfort. In view of the pronounced exophoria for close, clip-on prisms 3 Δ O.U. base-in were advised. These prisms made it easier for her to work but she still saw double images on week days, and now, not only at her desk, but also for distance. Whenever she drove home after work, road markings, headlights and traffic lights doubled up. She had the same diplopia with each eye separately and occasionally she saw three or four lights. It was not possible to provoke a diplopia at the office as the examinations always were made on Saturdays when she was not work-
ing. Red-light tests, the Lancaster tests, and fixation fields were normal. There was no metamorphopsia on the Amsler test. The tests were repeated with both pupils dilated and were again negative. The monocular diplopia tentatively was referred to the lens opacities, assuming that these opacities might be more noticeable over the glare of white paper on her desk. She was advised to use one-percent pilocarpine, hoping that this might take the offending lens opacities out of her field. She was asked to have a physical examination. The physical examination was negative except for a mild chronic gall-bladder disease. Pilocarpine gave very little relief. Mrs. D. was finally persuaded that she should be seen one evening after office hours so that the double images could be demonstrated. During this last evening examination a vertical diplopia was found in each eye. The two images were about two inches apart when checked at 20 ft. and approached each other some when coming closer but never became exactly one. Looking straight ahead the images of the two eyes covered each other completely. When shifting the gaze to the right or left, she mostly saw four lights. The size of the pupils was unchanged, and the refraction was the same, eliminating the possibility of a tension miosis and/or spastic myopia. Monocular diplopia has been referred to three main causes: Group I includes abnoimalities in the eye itself, irregularities in the cornea, pupil and lens, as well as specific diseases of the retina. Group II relates to projectional monocular diplopia which might occur in two ways : ( a ) a single retinal image is given two associations of direction, an innate normal projection and an acquired abnormal projection, depending on the development of abnormal correspondences ; ( b ) the image seen by an eccentric retinal point is brought into consciousness simultaneously with the macular image. This type of diplopia often is seen in connection with and treatment of amblyopia and squints.
SOCIETY
PROCEEDINGS
Group I I I refers to central monocular diplopia, a very rare condition. It might occur in lesions of the calcarine fissure. A new central functioning center or Pseudofovea may be established in the surviving part of the field. If this shift is incomplete, double vision may result. In cases of paresis of the extraocular muscles together with gross cerebral lesions, diplopia and secondary correspondence may develop. This phenomenon is probably caused by cerebral dissociation involving the independent activity of areas of the central cortex which normally act in association to produce a single sensory impression. Cases of this type have been described as occurring in various intracranial diseases. Monocular diplopia without manifest paralysis of any external eye muscle has been observed in the course of encephalitis, basal meningitis, multiple sclerosis and so forth. The same interpretation has been attempted to explain monocular diplopia of hysteria and functional disorders. Shift of spatial localization, namely, double vision of central origin may occur as a result of the acquirement of a double spatial conception in a damaged cortex. This most disagreeable condition is very obstinate and does not yield easily to any treatment.
467
they do, the vessels are secondary and do not resemble the normal retinal vascular pattern. Occlusion of one of the major arteries of the retina leads to marked edema of the retina which can be mistaken for detachment. Choroidal detachment, which may follow intraocular surgery, uveitis, or be spontaneous, can be differentiated from retinal detachment by the following points : 1. Choroidal detachments begin in the periphery and the ora serrata is clearly visible without pressure, since the choroidal detachment is pressing the retina inward. 2. The choroidal detachment is smooth with no folds. 3. The color of a choroidal detachment is darker than that of a retinal detachment. 4. Choroidal detachments are limited by the vortex ampullae. A cyclitic membrane, which has vessels, accompanying uveitis may resemble a retinal detachment. Cyclitic membranes usually begin inferiorly and the vascular pattern does not conform to the usual retinal pattern. Tumors of the choroid frequently are mistaken for detachment of the retina. Metastatic carcinoma tends to involve the posterior pole of the eye and results in a flat elevation of the choroid.
Schisis of the retina occurs in two forms: ( 1 ) a juvenile form which is rare and primarily involves young men who are subject to recurrent vitreous hemorrhages, and ( 2 ) the more common type known as the senile NEW ENGLAND type. Schisis can be differentiated from retOPHTHALMOLOGICAL inal detachment since the internal surface is SOCIETY smooth without folds, the vessels are frequently obliterated, there is a frosted apApril 26, 1961 pearance of the internal surface of the retD A V I D G. C O G A N , M.D., presiding ina and the field defects resulting from this condition have a steep edge. DIFFERENTIAL DIAGNOSIS OF RETINAL DETACHMENT A proliferating membrane in the vitreous due, for example, to diabetes can be conDR. ROBERT J . B R O C K H U R S T : A turbid vitreous from whatever cause can lead to a fused with retinal detachment A white flat mistaken diagnosis of retinal detachment membrane in the lower portion of the vitresince the choroidal pattern is obliterated. A ous may be the result of old hemorrhage in membrane in the vitreous may also be con- the vitreous and can be confused with retinal fused with a retinal detachment but these detachment. It is important to diagnose correctly semembranes do not have blood vessels or, if Ralph S. Hamilton, Secretary, Eye Section.