Epithelial ingrowth of anterior chamber and anterior surface of vitreous. (1/313)

This study is a case report of the histopathologic findings of the anterior chamber epithelial ingrowth in a patient who had penetrating injury in the right eye from an arrow approximately 20 years ago. The patient underwent the enucleation in the right eye due to pthisis bulbi and was fitted with a prosthetic eye. Specimens were prepared from the enucleated right eye for histopathologic observation using hematoxyllin-eosin to be observed under light microscopy. Epithelial ingrowth in the anterior chamber was noted in one layer or multi-layered epithelial cell growth. The ingrowth had spread to the posterior surface of the cornea to the anterior chamber angle, to the iris surface, and to the anterior surface of the vitreous. The finding suggests that epithelial ingrowth could invade even through a perforation site and spread wherever the cells could reach.  (+info)

Excimer laser effects on outflow facility and outflow pathway morphology. (2/313)

PURPOSE: To determine the relative contributions to aqueous outflow resistance of the tissues distal to the inner wall of Schlemm's canal. METHODS: While performing constant pressure perfusion at 10 mm Hg, a 193-nm excimer laser (Questek) was used to precisely remove portions of sclera, unroofing Schlemm's canal while leaving the inner wall intact. The laser beam was masked to produce a beam 2 mm by 1 mm. The laser output was constant at a fluency of 75 mJ/cm2 and 20 Hz. The excimer laser at a frequency of 1 Hz was used as the aiming beam. Photoablation was performed on human cadaver eyes at the limbus at an angle of 0 degrees to 45 degrees from the optical axis. As the excimer photoablations progressed, Schlemm's canal was visualized by the fluorescence of the Barany's solution containing fluorescein dye. After perfusion fixation the eyes were immersion-fixed overnight. The facility of outflow before (Co) and after (Ce) the excimer ablation was measured in 7 eyes. RESULTS: The facility of outflow increased in all eyes after the excimer sinusotomy, from a mean of 0.29+/-0.02 before the sinusotomy to 0.37+/-0.03 microl/min per mm Hg after (P < 0.05). The mean ratio of outflow facility after and before ablation (Ce/Co) was 1.27+/-0.08 (range, 1.20-1.39), a reduction of outflow resistance of 21.3%. Using the formula of Ellingsen and Grant (1972), percentage of resistance to outflow eliminated = 100 [1 - alphaCo/Ce - (1 - alpha)Co], where alpha = fraction of the circumference dissected. Assuming that because of circumferential flow approximately 50% of Schlemm's canal is drained by the single opening made in the outer wall ablation studies, this results in resistance to outflow eliminated of 35%, which is consistent with the calculated eliminated resistance derived from the data of Rosenquist et al., 1989. Light and scanning electron microscopy confirmed the integrity of the inner wall Schlemm's canal underlying the area of ablation. CONCLUSIONS: The results provide direct evidence indicating that approximately one third of resistance to outflow in the human eye lies distal to the inner wall Schlemm's canal in an enucleated perfused human eye.  (+info)

Coats' disease of the retina (unilateral retinal telangiectasis) caused by somatic mutation in the NDP gene: a role for norrin in retinal angiogenesis. (3/313)

Coats' disease is characterized by abnormal retinal vascular development (so-called 'retinal telangiectasis') which results in massive intraretinal and subretinal lipid accumulation (exudative retinal detachment). The classical form of Coats' disease is almost invariably isolated, unilateral and seen in males. A female with a unilateral variant of Coats' disease gave birth to a son affected by Norrie disease. Both carried a missense mutation within the NDP gene on chromosome Xp11.2. Subsequently analysis of the retinas of nine enucleated eyes from males with Coats' disease demonstrated in one a somatic mutation in the NDP gene which was not present within non-retinal tissue. We suggest that Coats' telangiectasis is secondary to somatic mutation in the NDP gene which results in a deficiency of norrin (the protein product of the NDP gene) within the developing retina. This supports recent observations that the protein is critical for normal retinal vasculogenesis.  (+info)

Effects of monocular enucleation on parvalbumin in rat visual system during postnatal development. (4/313)

PURPOSE: To evaluate the hypothesis that the expression of the calcium-binding protein parvalbumin (PV) in a subpopulation of gamma-aminobutyric acid (GABA)ergic neurons is an appropriate molecular marker for the effect on ocular dominance plasticity of monocular deprivation during the postnatal sensitive period. METHODS: Long-Evans rats underwent monocular enucleation immediately before eye opening (postnatal day [P] 14). Immunohistochemical analysis using anti-PV antibody was performed on the superior colliculus (SC) and lateral geniculate nucleus (LGN) at P45. In the visual cortex (VC) developmental changes in immunoreactivity were also examined at the ages of P17, P20, P27, and P45. Northern blot analysis for PV mRNA was also performed at P45. Changes in PV expression in the visual system of these rats were evaluated by use of a computer-based quantitative technique. RESULTS: PV-immunoreactive neurons were present in the SC and VC, whereas only a few were found in the LGN. The monocular enucleation at the onset of the sensitive period markedly reduced PV immunoreactivity in the neuropil of the SC, contralateral to the enucleated eye when examined one month later. No consistent and significant change in PV immunoreactivity was found in either the LGN or the VC. The number of PV-immunoreactive neurons in the VC rapidly decreased to the adult level during the middle of the sensitive period. The expression of PV mRNA in these central visual structures was not affected by early monocular enucleation. CONCLUSIONS: Expression of PV is developmentally regulated, and marked changes in its protein expression in the SC can be induced by monocular enucleation. Contrary to the original hypothesis, monocular enucleation did not consistently affect the expression of PV in the rat VC. The expression of PV is probably regulated by multiple factors, not merely by binocular competition.  (+info)

Effects of proton beam irradiation on uveal melanomas: a comparative study of Ki-67 expression in irradiated versus non-irradiated melanomas. (5/313)

AIMS: To assess the cellular proliferation using the monoclonal antibody Ki-67, in paraffin embedded uveal melanomas irradiated by proton beam, as well as in non-irradiated uveal melanomas. METHODS: 30 enucleated eyes were included for histopathological study and Ki-67 immunostaining. Patients were enucleated between 1991 and 1996 for uveal melanoma, 14 after proton beam irradiation and 16 without treatment (control group). The mean follow up period was 2.5 years after diagnosis and 1 year after enucleation. RESULTS: A significant relation was found between Ki-67 score and mitotic index (r = 0.56, p = 0.001), histological largest tumour diameter (r = 0.38, p = 0. 03), fibrosis (r = -0.35, p = 0.05), absence of tumoral pigmentation (p = 0.05), and presence of vascular thrombosis (p = 0.03). The Ki-67 score was significantly higher in the non-irradiated group (p = 0.01) and in the group of patients whose cause of enucleation was tumoral evolution (p = 0.005) compared with the group of patients enucleated after neovascular glaucoma. The Ki-67 score was very high in a case of orbital recurrence of uveal melanoma and metastatic death. 70% of metastasised tumours showed a Ki-67 score higher than the median value. CONCLUSION: Ki-67 labelling is a reliable method of estimating the proliferative activity in uveal melanomas after proton beam irradiation. The Ki-67 score is significantly correlated with prognostic variables (mitotic index and histological largest tumour diameter), and with radiation effects after proton beam irradiation.  (+info)

Painful blind eye: efficacy of enucleation and evisceration in resolving ocular pain. (6/313)

AIMS: To assess the effectiveness of enucleation or evisceration in relieving pain from painful blind eyes. METHODS: 24 patients with intractable ocular pain underwent enucleation or evisceration with or without an orbital implant. RESULTS: Complete pain relief was achieved in all patients at an average time of 3 months (range 1-15 months). Seven patients required further medical or surgical treatment in addition to removal of the globe. CONCLUSION: Enucleation and evisceration were effective in relieving ocular pain in all patients with a painful blind eye in our study. However, complications of surgery and orbital implants can cause recurrent pain.  (+info)

Equine phacoclastic uveitis: the clinical manifestations, light microscopic findings, and therapy of 7 cases. (7/313)

This retrospective clinical study describes the clinical manifestations, light microscopic findings, and diagnosis and treatment of acute and chronic lens rupture in the horse. Rupture of the lens capsule in the horse usually results in a chronic, blinding inflammation (phacoclastic uveitis) unless prompt surgical and medical therapies are implemented. The clinical manifestations of acute lens capsule rupture included: cataract; intralenticular displacement of iridal pigment; lens cortical fragments attached to the perforated lens capsule, iris, and corneal endothelium; miosis; aqueous flare; and usually a corneal or scleral perforation with ulceration or focal full thickness corneal edema and scarring. The clinical signs of chronic phacoclastic uveitis include blindness, phthisis bulbi, and generalized corneal opacification related to scarring, vascularization, pigmentation, and edema. In one horse, acute phacoclastic uveitis was successfully treated with phacoemulsification to remove the ruptured lens and medical therapy to control the accompanying inflammation. The affected eyes of the horses with chronic phacoclastic uveitis were enucleated because of persistent clinical signs of nonulcerative keratitis and uveitis, despite long-term medical management. The clinical manifestations and lack of improvement with medical therapy are similar in the horse, dog, cat, and rabbit. However, the histologic findings in equine phacoclastic uveitis differ significantly from those in the dog, and rabbit.  (+info)

Malignant melanoma of ciliary body: a case report. (8/313)

Ocular malignant melanomas are infrequently seen in Indian patents and most them involve the choroid. Ciliary body malignant melanoma is rather rare. This case report illustrates an occurrence in an Indian patient.  (+info)