University of Toronto Faculty of Medicine

SOCIETY PROCEEDINGS RDITKD πγ T H O M A S Ο Γ Α Ι . Κ Ι . Κ Υ , M . D .

UNIVERSITY O F TORONTO FACULTY O F MEDICINE D E P A R T M E N T OF O P H T H A L M O L O G Y

Abstracts of papers presented at the Seventh Annual Research Meeting M a y 1, 1965 INCORPORATION

OF RADIOACTIVE

PROLINE

INTO CORNEAL PROTEINS DR.

Y. M A T U K

(Toronto) : The

incor-

poration of radioactive proline into corneal proteins was studied. I t was found that glucose, T P N H and D P N H increased the incorporation of radioactivity. Reduced and oxidized glutathione and ascorbic acid, in concentrations of 1-4 μ. mole/ml, enhanced the incorporation. Increasing the concentration to 6 μ mole/ml, however, inhibited the uptake of radioactivity observed in the presence of glucose alone. Iodoacetate, p-hydroxymercuribenzoate, cysteine and puromycin produced considerable inhibition of uptake of radioactive proline by corneal proteins. THERMOELECTRICS IN RETINAL CRYOTHERAPY DR.

D. H. DICKSON

( T o r o n t o ) , M R . R.

C R U M P ( B r i d g e p o r t , Connecticut) A N D D R .

Μ. S H E A ( T o r o n t o ) : A new retinal cryosurgical instrument has been developed which utilizes expanding Freon gas to cool a thermoelectric system situated in the probe. This unit is portable, easy to operate and will attain a tip temperature of — 60°C. Animal experiments indicated that a firm chorioretinal adhesion develops within five days following application of the probe at —40°C. Temperature studies revealed that when the probe was applied at — 40°C the adjacent choroid and retina dropped to + 1.8°C. A n ice-ball formed, the temperature

of which was recorded at — 2°C. T h e ice-ball vitreous interface reached + 4 ° C . Fifty-three courses of treatment were carried out in 43 patients. These consisted of 19 retinal detachments and 2 4 with retinal degenerations (19 with and without breaks and five with retinoschisis). Of these, 17 were treated in the operating room and the remainder on an out-patient basis with local or topical anesthesia. Within five days the finely pigmented circular cryopexy lesion was visible and firm adhesion was apparent. N o complications incident to the use of cryosurgery occurred. EXTRAFOVEAL

STIMULATION

WITH

HIGH

INTENSITY LIGHT DRS.

J.

R.

ELDER

AND J.

C. M C -

CULLOCH ( T o r o n t o ) : T h e effects were studied of protecting certain areas of the retina from flash blinding exposure to light coming from the Meyer-Schwickerath light coagulator. It was found through two complementary experiments that once an intense light beam fell on the retina outside a fivedegree radius from the fovea, the protection of central vision was maximal and that further protection gave very little increase to the central visual recovery time. E F F E C T OF ARTIFICIAL FILTRATION ON CILIARY CIRCULATION DRS.

J.

Ε.

G R A H A M A N D R.

K. M A C -

DONALD ( T o r o n t o ) : T h e reduction of scierai rigidity in rabbits following artificial filtration operations and the persistence of this low rigidity, as long as filtration persisted, were noted. T h e scierai rigidity returned to control levels in all instances following death. These changes of scierai rigidity could be only accounted for by an increase in volume of the vascular pool of the eye which is maintained during life and which

1127

SOCIETY PROCEEDINGS

1128

collapses following death with the presence or absence of the venous pressure. Immediately following death, the ocular vessels were stained by means of injections into the internal carotid arteries. Intraocular vessels were examined and the following changes were noted in ciliary circulation in the operated eyes : 1. Extensive arteriovenous connections across pars plana between recurrent arteries of the major iris circle and the choroidal veins. 2. Increased size of capillaries in the ciliary processes, and an increase of caliber of veins of the processes to the choroid. 3. Narrowing in width of the pars plana with an apparent anterior movement of the choroidal veins and capillaries. These changes were due to dilatation of pre-existing vessels. SODIUM-POTASSIUM-ACTIVATKD ADENOSINE T R 1 P H 0 S P I I A T A S E I N CORNEA D R S . J. R. M I L L E R AND Y. M A T U K

(To-

ronto) : A T P a s e activity was studied in fresh bovine cornea. Epithelial and endothelial homogenates were incubated in a tris buffered medium (consisting of N a + 6 0 m M / l , K+10mM/l, Mg++9mM/l, CN-lOmM/1, E D T A O.lmM/1, A T P 6 m M / l , Tris-HCl 9 0 m M / l ) at p H 7.5. N o measurable activity could be detected in the stroma. T h e epithelium and endothelium contained appreciable amounts of A T P a s e activity. Absence of magnesium from the incubation medium produced considerable inhibition of all adenosine-triphosphatase activity. Na-K-activated A T P a s e activity was detected by the addition of ouabain or elimination of Na or K from the incubation medium. These values suggested active ion transport in both epithelium and endothelium. MOLECULAR BASIS OF VISUAL F U N C T I O N

D R . GEORGE W A L D

(Cambridge, Massa-

chusetts) : Vertebrate rods and cones contain an array of visual pigments which, when attacked by light, excite visual re-

sponses. All the visual pigments are built upon a common plan. All of them consist of a specific type of protein, opsin, carrying vitamin A aldehyde (retinene) as color group. T h e combinations of the two kinds of opsin, rod and cone, with the two kinds of retinene, 1 and 2, constitute the four major pigments of vertebrate vision. T o make a visual pigment requires a particular shape of the retinene molecule, the 11-cis isomer. T h e only action of light in vision is to change this 11-cis chromophore of a visual pigment to the all-trans configuration. All other aspects of the visual response represent dark consequences of this single light reaction. Many of the basic physiologic properties of vision are derived quantitatively from simple properties of these retinal molecules. T h e sensitivity of vision in the spectrum follows precisely the absorption spectra of the visual pigments. Light and dark adaptations—specifically their slow components—reflect directly the bleaching and regeneration of the visual pigments. The use of vitamin A aldehyde as chromophore of the visual pigments involves the visual processes with the supply of vitamin A in the diet, and the general metabolism of vitamin A throughout the organism. HYDRATION-TRANSPARENCY

STUDIES

IN

CORNEAL STROMA

DR. B. ZUCKER ( T o r o n t o ) : T h e effect of corneal stroma hydration on transparency in terms of visual acuity was investigated. Calf corneal stroma was used as a filter between the investigator's eye and a target. T h e resulting visual acuity was plotted against the hydration which was determined in each of 80 experimental corneas. T h e r e was definite evidence that visual acuity was relatively unaffected by increasing stromal edema until the thickness of the stroma increased by 7 0 % . T h e effect of the epithelium on transparency was not studied.

SOCIETY PROCEEDINGS R E T I N A L INVOLVEMENT CEREBRAL

FOLLOWING

INOCULATION

MOUSE CATARACT AGENT DRS. J.

ELIZABETH

SHEFFER,

H.

OF

(SMCA)

OLMSTED, F.

INTRA-

SUCKLING

CLARK

S. AND

PRASAD, D.

T.

KARZON (Buffalo): Histopathologic retinal changes in C57 mice inoculated intracerebrally on the first day of life with suckling mouse cataract agent ( S M C A ) were devastating. Early in the second week focal capillaritis developed in the nerve-fiber layer followed by cystoid changes extending into the inner nuclear layer. Progressively, intense posterior uveitis (sometimes accompanied by scleritis) developed, with exudation into the outer portion of the retina by polymorphonuclear leukocytes and mononuclear cells. T h e pigment epithelium degenerated and proliferated and there was dispersion of pigment which became collected in large macrophages. Cystoid degeneration was severe throughout. Rods and cones disappeared and the nuclear layers became combined. Accompanying the gradual resolution of the exudate was a reduction of all cellular elements of the retina with the inner nuclear layer most resistant. T h e final appearance as studied at 60 days was an atrophie retina (sometimes a single cell layer) with irregular distribution of pigment throughout. EVALUATION

OF

THE

RESULTS

OF

PTOSIS

SURGERY DRS.

Y.

DAYAL

AND

J.

S.

CRAWFORD

( T o r o n t o ) : This paper analyzed the results of the repair of congenital ptosis at the Hospital for Sick Children, Toronto, during the years 1959 to 1963. T w o hundred and five patients with congenital ptosis operated by different methods—levator resections (transcutaneous approach, transconjunctival approach and levator tucking), frontalis procedures (fascia lata sling and collagen tape sling) and combined procedures (levator frontalis sling)—were reviewed. T h e relative merits and demerits of the

1129

various techniques and their functional results have been evaluated and the choice of approach to achieve the best cosmetic results was indicated. T h e various pitfalls and complications that are likely to be encountered, and how best they may be avoided and treated, were discussed. INTRAOCULAR HEMORRHAGES I N

WEANLING

RATS FOLLOWING A VARIETY OF PROCEDURES M R . R.

A.

BEAR AND D R . W .

S.

HART-

ROFT ( T o r o n t o ) : Hemorrhages of the hyaloid arterial system, both in choline-deficient and bilaterally nephrectomized weanling rats had been described previously by several investigators. T h e authors conducted an investigation of the causes of these lesions, utilizing a variety of surgical, dietary and pharmaceutical procedures. T h e effects of variations in respiratory environment also were studied, using atmospheres of high oxygen content. T h e surgical procedures employed included unilateral and bilateral nephrectomy, unilateral and bilateral adrenalectomy, ureteral ligation, hemorrhagic shock, pancreatectomy, parathyroidectomy and splenectomy. Other conditions tested either individually or in conjunction with the surgical methods, comprised choline deficiency, potassium deficiency, hormonal therapy ( r e n i n ) , production of hyperoxia and anoxia and administration of vasopressor and vasoconstrictor drugs. A comparison of the effects of these procedures was made on the basis of ability to produce the lesions, intensity of the hemorrhages, percentage of animals developing hemorrhages and time needed for the pathologic condition to develop to a recognizable degree. A comparative index was calculated for each of the methods. Results indicated that this type of ocular hemorrhage in weanling rats could be produced by most of the procedures just indicated. T h e fundamental mechanism involved, however, still remains to be elucidated.

SOCIETY PROCEEDINGS

1130 FURTHER

STUDIES

ON T H E

COLD PRECIPITATING

LENTICULAR

PROTEIN

D R S . S. Z I G M A N AND S. L E H M A N

(Roch-

ester, New Y o r k ) : Alpha, beta and gamma crystallins, which comprise the cold precipitable protein ( o r C P P ) and the total soluble minus cold precipitable protein ( o r T M C P ) fractions in rat lenses, were isolated using columns of sephadex G 100 and DEAE-cellulose. Studies of the effects of lowered temperatures (0° to 10°C) on the solubilities of these crystallins showed that gamma-crystallin, when taken alone, exhibits the property of cold insolubility whether it was derived from the C P P or T M C P fraction. Precipitation of gamma-crystallin below 10°C, a phenomenon which may depend upon the presence in the protein of many amino acids containing apolar or hydrophobic side chains, was prevented by relatively high concentrations of alpha and beta crystallins. A relationship between transparency of the lens and physicochemical interactions between soluble proteins was thus demonstrated. O P H T H A L M O L O G Y AND T H E MEDICAL ARTISTMISS JUDITH

GEBITARD

(Toronto):

The

value of artistic representation of clinical and research materials at meetings and in journals was discussed. It is necessary that both the investigator and the artist should understand each other's problems before undertaking any project. I n this respect medical training of the artist is of great advantage. Different techniques involved in presentation of visual aids were discussed. Various materials and the air-brush technique were demonstrated. REGENERATION

AND HYPER-REGENERATION

OF CORNEAL NERVES DR.

J.

REIMER

WOLTER

(Ann

Arbor,

Michigan) : Histologie study of regeneration and hyperplasia of corneal nerves, in cases of old phthisis bulbi, ocular neurofibromatosis, neuroparalytic keratopa-

thy after preganglionic sectioning of the fifth nerve and in opaque corneal buttons after penetrating keratoplasty, allowed for a more complete description and a better understanding of so-called "hyper-regeneration" of corneal nerves. T h e main observations of this study were that : 1. A tremendous increase of nerves might be seen in the cornea under various chronic pathologic conditions. 2. O f the three different nerve types normally found in the cornea, the thin nerve fibers proliferated most while the thick fibers mainly showed an increase of their superficial terminal branches only. 3. Large bundles of the thin nerves entered the corneal stroma along with newformed blood vessels in corneal vascularization. Extensive proliferation of thin corneal nerves only was seen after preganglionic sectioning of the fifth nerve. 4. Hyper-regeneration of nerves may extend into the deep corneal stroma, and nerve branches were found on and within the corneal endothelium in such cases. It was concluded that the cornea is an ideal site for studies of the fascinating and virtually unknown process of nerve hyper-regeneration. This has already been observed to occur, also, for example, in the corneoscleral trabecula in glaucoma and in diabetic retinopathy. P R E V E N T I O N OF A GENETICALLY DETERMINED CONGENITAL BY PRENATAL

EYE DEFECT I N T H E MOUSE CORTISONE

M R S . M U R I E L J. H A R R I S D R . J A M E S R. M I L L E R

TREATMENT (Toronto) AND

(Vancouver):

The

mouse is normally born with its eyelids fused. T h e lids fuse during day 16 of gestation (full-term 19-20 days) and separate again approximately 14 days after birth. A failure in eyelid fusion (open eye at birth) constitutes a congenital defect in the mouse. It may be caused by either genetic or environmental teratogens and results in abnormalities in the adult eye. Open eye at birth was observed in the

SOCIETY PROCEEDINGS C 3 H / M 1 strain of mice several years ago. Breeding tests indicated that the defect was caused by a single autosomal recessive gene, l g . Approximately 7 0 % of the homozygotes ( l g / l g ) had the defect. Cortisone, when administered to pregnant females prior to day 16 of gestation, reduced the frequency of defective newborns from 7 0 % to 0 % . Preliminary histologie studies indicated that the corneal and eyelid epithelia were stuck together in l g embryos. L I Q U I D NITROGEN CRYOSURGERY OVER VORTEX V E I N S DRS.

D.

H.

DICKSON

AND

C.

B.

MOR-

TIMER ( T o r o n t o ) : T h e probe of a Linde cryosurgical unit was applied at —40°C over and adjacent to the superior vortex veins. Twenty-seven eyes were treated, varying the time of application from two to 10 seconds. W i t h application there was immediate cessation of blood flow in the choroidal and retinal vessels and the vortex veins. U p o n removal the blood flow was immediately reestablished. Initially the conjunctiva was edematous and showed fine speckling of ecchymosis which lasted for three to four days. After one week, the conjunctiva was normal in all respects. Within one to two weeks a sharply demarcated lesion 3-5 mm in diameter was noted. Following removal at time intervals from two to 20 weeks, the eyes were fixed in formalin. All eyes treated for longer than three seconds exhibited firm attachment at the lesion site. T h e vortex veins were patent in all eyes treated less than 10 seconds. L E I O M Y O M A OF T H E I R I S DR.

JAMES

G.

FOWLER

(Buffalo,

New

Y o r k ) : A case of leiomyoma of the iris in a psychopathic female was described and compared with other reported cases. T h e tumor was associated with a mature cataract, so a combined intracapsular cataract extraction was done, the tumor being included in the iridectomy. There was extension of the mass into the ciliary body so it was only

1131

partly removed ; in effect only a biopsy specimen plus a cataract extraction. T w o years later there was no extension of the tumor and the eye had 20/20 corrected vision. T h e patient died seven years later of cardiac failure. N o evidence of melanotic metastasis was found at autopsy. T h e first pathologic report was spindle type-A melanoma, malignant, but the pathologist later amended the diagnosis after special stains demonstrated the pallisade cell arrangement characteristic of leiomyoma. The case illustrates the benign character of the tumor and the fact that it is seldom diagnosed before surgery and that the pathologic differentiation from malignant melanoma is difficult. Colored photographs before and after surgery were shown. CURVATURE I N T H E SACCADIC M O V E M E N T DR.

E.

LLEWELLYN

THOMAS

AND

MR.

H . O ' B E I R N E ( T o r o n t o ) : E y e marker camera recordings of a number of subjects under various experimental conditions showed that about one third of the saccadic pathways were curved by more than one degree of visual angle. They occurred along all axes and in all parts of the recorded visual field (30° X 2 0 ° ) . Straight and curved movements occurred under the same conditions and in the same subjects. Secondary corrective movements were not markedly more frequent after curved movements than after straight ones. If each saccade is preprogrammed in the central nervous system, the signals to the muscles need not be synchronized for the eye to arrive successfully at its new fixation point. However, the shape of the interfixation path will be a function of the time differences between the arrival of the signals at the muscles. Random time delays result in a random sequence of straight and curved pathways not related to position or direction. T h e nature of the intersubject variation in the magnitude and incidence of curved

SOCIETY PROCEEDINGS

1132

movements suggested their occurrence maybe of some diagnostic interest. COMPARISON OF PREOPERATIVE HYPOTENSIVE

AGENTS DRS.

B.

ST.

L.

LIDDY

AND

S.

R.

F R A N K L I N G ( T o r o n t o ) : Fifty-percent glycerol, in a dosage of 1.5 ml per kg, was compared to 500 mg of Diamox as preoperative hypotensive agents in cataract surgery. Anal3'sis of results revealed little difference in hypotensive effects obtained between 5 0 % glycerol used one hour preoperatively and 500 mg of oral Diamox administered three hours preoperatively. I n almost half the cases a fall of intraocular pressure greater than 6 mm H g was obtained. Expected hypotensive levels for any one case could not be predicted preoperatively. M E C H A N I S M OF H U M A N COLOR VISION

D R . GEORGE W A L D

(Cambridge,

Massa-

chusetts) : T h e difference spectra of the green- and red-sensitive pigments of color vision were recently measured by the direct microspectrophotometry of human foveas. It was possible to measure the difference spectra of the visual pigments in single blue-, green- and red-sensitive cones of the parafovea. A simple sensory procedure was developed also for determining the action spectra and, by correction, for the transmission of light by the ocular media, the absorption spectra of the color vision pigments. All these measurements agreed reasonably well. T h e spectra of these pigments accounted for the total luminosity function, and provided a simple explanation for all known forms of human color blindness. S E N I L E LENS EXFOLIATION: A N ELECTRON MICROSCOPIC STUDY DRS.

J.

S.

SPFAKMAN

AND

T.

Y A M A S H I T A (Toronto) : Although more than 30 years have elapsed since the first morphologic studies of capsular exfoliation were published, there is still no general agreement as to its true nature. T h e limited

resolving power of the light microscope makes it impossible either to identify the exfoliation material with certainty or to determine accurately its relationship to the lens capsule. I n order to overcome these difficulties, electron microscopy, in addition to light microscopy, was employed to examine several lenses with typical patterns of exfoliation which were removed in capsule with an erisophake. In areas where there appeared to be a membrane separating from the lens capsule, electron microscopy showed folding and elevation of the zonular lamella. I n areas where light microscopy showed the characteristic brush pattern, the zonular lamella showed an extreme degree of fragmentation and in places was absent. Elsewhere light microscopy showed an appearance resembling a deposit of "potato chips" on the lens capsule, and these areas by electron microscopy corresponded to regular corrugations of the zonular lamella, suggesting a fragmentation into spiral or corkscrew structures. I n other areas where the pigment epithelium was adherent to the lens, the zonular lamella showed dissociation and disorientation of the fibrils. I n summary, electron microscopic examination showed that abnormalities of the lens capsule, seen in cases of capsular exfoliation, were the result of pathologic alterations in the zonular lamella. FURTHER

STUDIES

ON T H E TRANSPLANTA-

T I O N OF HUMAN BRAIN TUMORS TO THE

ANTERIOR CHAMBER OF GUINEA-PIG EYES D R S . C. H . TATOR, T . P. M O R L E Y A N D P .

K. B A S U ( T o r o n t o ) : H u m a n brain tumors removed surgically were transplanted to the anterior chamber of the eyes of untreated guinea pigs. O n e glioblastoma multiforme has been maintained for three years and is now in its seventh generation in guinea pigs. Changes occurred in the histologie appearance of the tumor in guinea pigs but certain features of the human tumor were retained. When a tumor grew large enough to occu-

SOCIETY PROCEEDINGS

py the anterior chamber it was transplanted to the opposite eye. In most instances, growth occurred in the opposite eye, indicating that growth in the first eye failed to immunize the second eye against the tumor. The significance of this finding was evaluated. The factors considered responsible for the infrequency with which human brain tumors metastasize to sites outside the central nervous system were reviewed.

1133

cessibility, general low malignancy and infrequent métastases. Better cosmetic and functional results were also obtained. PATENCY OF THE LONG POSTERIOR CILIARY ARTERIES IN CHRONIC GLAUCOMA DRS.

J.

C.

MCCULLOCH

AND

J.

A.

(Toronto) : The long posterior ciliary arteries from 24 enucleated human eyes with chronic glaucoma were studied with a view to finding an explanation for the iris atrophy and trabecular changes in middleaged patients with glaucoma. Strips of sciera and choroid containing the arteries were sutured at both ends and mounted under tension to prevent curling and kinking during fixation and dehydration. Samples of serial sections 5 ηιμ. in thickness showed the lumen of the long posterior ciliary artery to vary from 50 ηιμ to 150 ιτιμ. The proximal extrasderal portion of the artery was not examined. No obstruction of the intrascleral and suprachoroidal portions of the arteries could be demonstrated. PARKER

SURGICAL TREATMENT OF TUMORS OF THE EYELIDS

DRS. Y. DAYAL AND J. C. H I L L (Toron-

to) : The study presented 65 cases of lid tumors that were surgically excised, histopathologically diagnosed and adequately followed. After outlining the general principles of treatment, the various procedures used in the reconstruction of the eyelids, depending upon the extent of the ltd loss, along with results and complications, were described. The preference of surgical excision with subsequent repair to radiation therapy was stressed in view of the tumors' unique ac-

P. K. BASU.

O P H T i i A L M 1C

MlNIATURF.

He looked up quickly in embarrassment. His "sorry" coincided with at least two Gesundheits. Why say it in German ? he wondered. He was briefly conscious that Charles Joyce was staring hard at him. He looked down again in reflex to the linen in his hand. In horror he saw between two folds a tiny semisphere of green-tinted, paper-thin plastic. Quickly he forced a strangled cough, and pressed the handkerchief again to his face. " 'Scuse me," he mumbled through it. "Be right back." It was a difficult business, he found, to replace the little lens with hands that were shaking so. The Man in the Mirror A spy novel by Frederick Ayer, Jr. Chicago, Regnery, 1965