Pleomorphic adenocarcinomas of the ciliary epithelium. Immunohistochemical and ultrastructural features of 12 cases.

OBJECTIVE: To examine the immunohistochemical and ultrastructural features of the rare pleomorphic adenocarcinomas of the ciliary epithelium (CE). DESIGN: Retrospective case series. PARTICIPANTS: The study materials included 12 cases of adenocarcinoma of the ciliary epithelium: 9 cases of CE hyperplasia and 3 cases of CE adenomas. INTERVENTION: Histologic sections were stained with hematoxylin-eosin, alcian blue, periodic acid-Schiff, and occasionally with Masson trichrome. Additionally, the following immunohistochemical markers were used: Kermix (ae1/ae3 + ck1), cytokeratin 7 (CK7), cytokeratin 20 (CK20), epithelial membrane antigen, CAM 5.2, S-100 protein, neuron-specific enolase, glial fibrillary acid protein, smooth muscle actin, and vimentin. Five lesions were studied ultrastructurally. Clinical data were available in all cases, and follow-up was obtained in 9 of the 12 patients. RESULTS: Nine tumors occurred in phthisical eyes in adults. The tumor cells were arranged in tubular and solid patterns and surrounded by thick basement membrane (BM) material and fibrous stroma. Immunohistochemistry (IM) of adenocarcinomas showed positivity with kermix (8 of 12 lesions), CAM 5.2 (7 of 12), and CK7 (5 of 12). Ultrastructurally, the tumor cells were surrounded by a thick, homogeneous, and/or multilaminar BM and attached to each other by junctional complexes. CONCLUSIONS: Clinically, this intraocular neoplasm should be considered in adults with a longstanding blind eye with an epibulbar mass and/or proptosis of recent duration. Fatal cases only occurred in tumors with extraocular extension. Adenocarcinomas of CE should be differentiated from amelanotic melanoma and metastatic lesions by the presence of a thick BM material around the tumor cells and intraocular fibrosis. Immunohistochemistry is helpful in differentiating from melanomas but not helpful in cases of metastatic carcinomas.

Mild form of Maroteaux-Lamy syndrome: corneal histopathology and ultrastructure.

PURPOSE: Maroteaux-Lamy syndrome is one of the mucopolysaccharidoses (MPSs) that is caused by the incomplete degradation and storage of dermatan sulfate. METHODS: We describe a 49-year-old female patient with the mild form of the disease (MPS VI-B) who developed bilateral increasing corneal opacification and increased intraocular pressure after cervical-fusion surgery. After treatment of the increased intraocular pressure, she underwent a penetrating keratoplasty of her right eye. RESULTS: The histopathologic and ultrastructural features of the corneal button were the accumulation of membrane-bound vacuoles containing fibrillogranular and lamellated material in keratocytes and endothelial cells and thinning of Descemet's membrane with excrescences. CONCLUSION: Our review of the literature reveals only two prior histologic studies of corneas affected by MPS VI B.

Efficacy of treatment after measurable diabeticlike retinopathy in galactose-fed rats.

PURPOSE: To determine whether the diabeticlike retinal microangiopathies of the galactose-fed rat model could be ameliorated if intervention by withdrawal of the galactose diet or treatment with the aldose reductase inhibitor AL-3152 was initiated after quantifiable microangiopathies had occurred. METHODS: Weanling male Sprague-Dawley rats were randomized into five groups and fed for up to 24 months Purina laboratory chow (#5001) plus 50% starch (control [CON]), 50% D-galactose (galactose [GAL]), 50% D-galactose with AL-3152 (approximately 14 mg/kg per day) (prevention [PRV]), 50% D-galactose for 6 months followed by intervention with the inhibitor (intervention [INT]), or 50% D-galactose for 6 months followed by replacement with the 50% starch diet (withdrawal [GWD]). In rats on experimental diets and killed after 6, 18, and 24 months, one retina was prepared for transmission electron microscopy; the other was used for vessel wholemounts using elastase digestion. Capillary images were analyzed by computer morphometry. RESULTS: At 6 months, the GAL rats exhibited statistically significant (P < 0.05) increases over CON rats in mean capillary basement membrane thickness, capillary density, and dilated channels. These parameters tended to increase with time in most groups, and the differences between GAL and age-matched CON rats were maintained at the 18- and 24-month endpoints. Although the microangiopathies were ameliorated by AL-3152 treatment from the onset (PRV), intervention after 6 months of galactosemia with either galactose withdrawal (GWD) or addition of inhibitor (INT) showed amelioration in only some parameters at 18 months and no statistically significant benefit at the 24-month endpoint. CONCLUSIONS: Amelioration of galactose-induced retinal microangiopathies with AL-3152 in the prevention group suggests an efficacious application of aldose reductase inhibitors in treating diabetic retinopathy, provided treatment can begin soon after the onset of diabetes. Intervention after some of the earliest microscopic lesions neither halted progression of the angiopathy nor provided appreciable benefit at the 24-month follow-up.

Diabetic-like retinopathy ameliorated with the aldose reductase inhibitor WAY-121,509.

PURPOSE: To evaluate the efficacy of WAY-121,509, a potent new aldose reductase inhibitor (ARI), in preventing the retinopathy that develops in the galactose-fed rat model of diabetic ocular complications. METHODS: Sprague-Dawley rats were randomized into treatment and duration groups and fed diets with either 50% starch of 50% galactose with or without WAY-121,509 (25 mg/kg body weight per day). Progression of cataracts was monitored by slit-lamp biomicroscopy. After duration of 4, 8, 16, and 24 months, levels of plasma glucose and glycated hemoglobin, as well as erythrocyte and retinal galactose and galactitol, were measured in rats in each group. Retinal vasculatures of the 24-month rats were isolated by elastase digestion and analyzed by computer-assisted morphometry. RESULTS: Mature, diabetic-like cataracts developed within 5 weeks in all the galactose-fed, untreated rats, but only nonprogressive anterior cortical opacities were present in lenses of 85% of the ARI-treated galactosemic animals after 3 months. Plasma glucose remained the same in all groups. Erythrocyte and retinal galactose and glycated (galactosylated) hemoglobin were elevated with galactosemia and were unaffected by ARI treatment. Erythrocyte and retinal galactitol levels were decreased by 91% and 95%, respectively, with inhibitor treatment. At 24 months, capillary length, width, density, the number of microaneurysms, and the percent of capillary length involved in intraretinal microvascular abnormalities, expressed as hypercellular channels with diameters > 20 microns, were significantly increased by galactosemia and were attenuated in the galactose-fed, ARI-treated group. CONCLUSIONS: A dose of WAY-121,509 sufficient to reduce retinal polyol levels by 95% ameliorated the development of galactose-induced cataracts and diabetic-like retinopathy but was insufficient to prevent early lens opacifications or all the diabetic-like retinal microangiopathies.

Histological evaluation of the canine retinal vasculature following chronic systemic administration of basic fibroblast growth factor.

The purpose of the present study was to determine if prolonged systemic arterial administration of basic fibroblast growth factor (bFGF) at a dose sufficient to enhance collateral vessel formation in the ischaemic hearts of dogs would produce retinal neovascularisation in these same animals. Adult dogs (15-25 kg) were subjected to gradual occlusion of a coronary artery and randomised to receive 1 of 3 treatments via an indwelling left atrial catheter: (1) bFGF 1.74 mg/d, 5 d/wk for 63 d (n = 7); (2) bFGF 1.74 mg/d, 5 d/wk, for 35 d followed by physiological saline, 5 d/wk, for 28 d (n = 10); or (3) physiological saline, 5 d/wk, for 63 d (n = 10). After 63 d the retinal vasculatures from these dogs were isolated and examined for capillary varicosity, neovascularisation and other histopathological signs of angiopathy. All data were collected under masked conditions. The results suggest that chronic, systemic arterial administration of bFGF stimulates neovascularisation in the ischemic myocardium, but has no significant structural or vasoproliferative effect on the nonischaemic retina of the same animal.

Sorbinil prevention of diabetic-like retinopathy in the galactose-fed rat model.

PURPOSE: To determine if the retinal microangiopathies of the galactose-fed rat model of diabetic retinopathy can be prevented with the aldose reductase inhibitor sorbinil. METHODS: Sprague-Dawley rats were fed 50% d-galactose with or without sorbinil (0.05% wt/wt), mixed biweekly with fresh diet. Rats in each group were examined frequently by slit lamp and were killed after 8, 16, and 24 months. Computer-assisted morphometry was performed on wholemounts of elastase retinal digest preparations. RESULTS: Cataracts developed in all galactose-fed untreated rats within 3 weeks but not in the sorbinil-treated rats even after 24 months. At 8 months, the galactose-fed untreated rats exhibited statistically significant increases in the mean capillary width, the percent of retinal area occupied by capillaries (capillary density), and the percent of microvascular area with capillaries > 20 microns wide (dilated channels), compared to controls. At 16 months, the galactose-fed untreated rats showed statistically significant increases over controls in both total mean capillary length and density, and two of the four rats examined had microaneurysms. At 24 months, all the galactose-fed untreated rats had microaneurysms and extensive areas with hypercellular meshworks composed of dilated channels characteristic of intraretinal microvascular abnormalities (IRMA). By contrast, galactose-fed, sorbinil-treated rats, at 24 months, had no IRMA and showed no statistically significant differences from control rats in any of the parameters measured morphometrically. CONCLUSIONS: All the galactose-induced retinal microangiopathies were prevented with sorbinil. Aldose reductase inhibitors may be beneficial in ameliorating the similar vascular lesions characteristic of human diabetic retinopathy, though the mechanism remains obscure.

Novel procedures for isolating intact retinal vascular beds from diabetic humans and animal models.

PURPOSE: To improve the 30-year-old "trypsin digestion" procedure for isolation of the complete retinal vasculature, which, in its time, was a revolutionary advance that allowed important discoveries about diabetic retinopathy; to provide a method that will yield more consistent results when applied to retinas representing a wide range of ages, species, and severity of vascular disease, such as that occurring in diabetes. METHODS: Because the Difco trypsin preparation (Difco Laboratories, Detroit, MI) is a crude pancreatic extract, containing variable amounts of chymotrypsin, elastase, amylase, lipase, ribonuclease, collagenase, and other contaminants, an attempt was made to determine which of the major enzymes alone (using purified preparations), or what combination of enzymes, might be most effective in providing consistently clean yet intact retinal vasculatures from eyes of different origins. RESULTS: Purified elastase alone (40 U/ml) in 100 mmol/l sodium phosphate buffer with 150 mmol/l sodium chloride and 5 mmol/l EDTA at pH 6.5 and 37 degrees C gave better results than various concentrations of purified trypsin or chymotrypsin alone, or mixtures of trypsin/chymotrypsin, trypsin/elastase, chymotrypsin/elastase, or the crude trypsin preparation. CONCLUSIONS: Elastase, which exhibits broad protease activity, and not trypsin, is the most important enzyme of the standard, crude trypsin digestion procedure for removal of the nonvascular tissues of the retina.