Peter H. Morse

Does Microaneurysm Count Reflect Severity of Early Diabetic RetinoPathy

In a group of 55 insulin-dependent diabetic patients with early diabetic retinopathy, microaneurysm counts from fluorescein angiograms were related to the level and severity of retinopathy derived by grading eight standard stereo color photographs as used in the Early Treatment of Retinopathy Study (ETDRS). All patients were studied at 0, 8, and 24 months. Significant correlations were present between both definite and possible microaneurysm count and retinopathy level of the eye studied and the mean retinopathy level of the two eyes, at all three time intervals, (P less than 0.05-less than 0.001). Similarly, there were significant correlations between microaneurysm counts and severity of the following lesions: microaneurysms and haemorrhages, cotton-wool spots (P less than 0.05-less than 0.001); to a lesser degree, severity of hard exudates (P less than 0.1-less than 0.001) and intraretinal microvascular abnormalities (P not significant-less than 0.001). There was no correlation between microaneurysm count and venous abnormalities (as at no time were there more than 11 eyes with any venous abnormality). We conclude that microaneurysm counts from fluorescein angiograms accurately reflect the severity of important signs in early diabetic retinopathy.

Bilateral Juxtapapillary Subretinal Neovascularization Associated with Pseudotumor Cerebri

A 32-year-old obese woman with hypertension and a three-year history of pseudotumor cerebri developed bilateral juxtapapillary subretinal neovascular membranes. To our knowledge, this is the first reported case of bilateral subretinal neovascular membranes complicating the course of this disease. The subretinal neovascular membrane in the left eye spontaneously involuted, but because the membrane in the right eye threatened the foveola, the patient underwent argon-laser photocoagulation. The subretinal fluid and hemorrhage progressively resolved, the membrane was replaced by fibrous tissue, and visual acuity improved. The pathogenesis of the subretinal neovascular membranes was presumably secondary to pressure deformity of the border of Bruchs membrane at the optic disk, creating a discontinuity of normal anatomic apposition of the chorioretinal layers. This anatomic dehiscence, coupled with hypoxia created by axonal tissue swelling and resultant impaired vascular perfusion of the tissues, led to the development of subretinal neovascular membranes.

Ichthyosis Hystrix (Epidermal Nevus Syndrome) and Coats' Disease

A 4-year-old girl had the ichthyosis hystrix variant of the epidermal nevus syndrome with ocular fundus manifestations of Coats disease. Her hearing was impaired because of serous otitis media and her visual acuity decreased because of hard yellow exudate in the macula as a result of decompensation and plasma leakage from the peripheral retinal vascular anomalies. Treatment of the vascular malformations with cryotherapy resulted in a reabsorption of the retinal edema and hard yellow exudate.

Retinopathy Associated with Acute Pancreatitis

Two patients (a 28-year-old woman and a 23-year-old man) with acute pancreatitis developed severe visual loss. The acute stage of retinopathy consisted of retinal edema, cotton-wool patches, and retinal hemorrhages, predominantly in the posterior pole of both eyes. During the five-year follow-up period, visual acuity improved and sequential fluorescein angiography of both patients demonstrated reperfusion of previously occluded retinal vessels. After resolution of the cotton-wool patches, the previously edematous areas were replaced by foci of retinal thinning which created irregularities in the internal limiting membrane light reflex. Visual fields demonstrated scotomas corresponding to the areas of the previous cotton-wool patches.

Herpes Simplex Type 1 Retinitis in an Adult with Systemic Herpes Zoster

A 72-year-old man developed bullous skin lesions two months before he was discovered to have malignant lymphoma. Herpes zoster virus grew from the skin bullae. He developed encephalitis, keratitis in the left eye, and bilateral retinitis 18 months later. Herpes simplex virus type 1 grew from cultures of the eyelid vesicles and corneal scrapings from the left eye. The patient died two years after the diagnosis of malignant lymphoma. Virus particles believed to be herpes simplex virus were demonstrated on electron microscopy in the necrotic retinal cells.

Platelet-Induced Retinal Neovascularization in Leukemia

Retinal changes resembling those of background diabetic or hypertensive retinopathy commonly occur in leukemia, whereas retinal neovascularization is rare. When neovascularization does occur, it is usually the result of hyperviscosity caused by a greatly increased number of circulating leukocytes. A 42-year-old woman with diabetes mellitus developed chronic myelocytic leukemia and peripheral retinal neovascularization. The hyperviscosity leading to the neovascularization was probably caused by an increased number of circulating platelets.

The Relationship Between Retina Surgery and Preretinal Macular Fibrosis

A prospective study of 440 eyes of 220 patients following successful operations for primary rhegmatogenous retinal detachment (132 eyes) and prophylactic operations for retinal breaks (103 eyes) revealed an incidence of preretinal macular fibrosis (PRMF) of 47% after scleral buckling surgery and 42% after prophylactic laser or cryopexy. The incidence of PRMF was significantly greater in aphakic vs phakic detachments, in detachments with operculated vs horseshoe breaks, in detachments with horseshoe breaks vs lattice degeneration, in detachments involving the macula, after scleral buckling with cryotherapy vs diathermy, and after prophylactic treatment of retinal breaks of fellow eyes with retinal detachment or retinal breaks that had developed postoperative PRMF. Analysis of the data suggests that PRMF is most likely a result of the retinal break, detachment, and subsequent treatment.

Autosomal dominant central pigment epithelial and choroidal degeneration.

Eight of nine individuals of a four-generation family had autosomal dominant central pigment epithelial and choroidal degeneration, which was not entirely consistent with previously described central retinal and choroidal degenerations. The early loss of the choriocapillaris with a relative sparing of the sensory retinal and pigment epithelial function is similar to central areolar choroidal degeneration. Ophthalmoscopically, however, the disease resembled the dominant progressive foveal degenerations; except that our patients additionally had multiple peripheral yellow-white lesions. An exceptional finding in our patients was the preservation of good visual acuity despite marked atrophy of the choriocapillaris.

Pseudohypopyon in Best's Vitelliform Macular Dystrophy

We examined ten eyes with pseudohypopyon in seven patients with Bests vitelliform macular dystrophy. Fluorescein angiography showed hyperfluorescent defects in the retinal pigment of the superior half of the lesion in all ten eyes. The electro-oculographic findings were abnormal in all four patients who underwent this test. The fluid shifted slightly in two of six patients whose heads were turned to the side for an hour or longer, indicating that the material was probably located between the retinal pigment epithelium and the sensory retina. The volume of the hypopyon increased in one eye.

Fundus Flavimaculatus with Cystoid Macular Changes and Abnormal Stiles-Crawford Effect

A 13-year-old boy with fundus flavimaculatus had a macular disease consisting of many transparent cystoid spaces which were not hyperfluorescent on fluorescein angiography. The Stiles-Crawford effect was abnormal, suggesting that the cystoid changes in the maculas created a disorientation of the patients foveal retinal photoreceptors.