No abstract available.
Behcet Syndrome*

No abstract available.
Behcet Syndrome*

Gas tamponade is sometimes necessary after vitrectomy. Accurate measurement of intraocular pressure(IOP) in gas-filled eye is important, but is hard to get in operating table, because of lack of a good measuring device. Schiotz tonometry is the only possible method, but it usually gives a lower value than real, because gas-filled eye has a greater compressibility. But if the Schiotz tonometry can give a consistant value in relation to the real value, one can assume a true IOP by simply converting the value, and it will help the vitrectomy surgeon. Vitrectomy with or without lensectomy were done in 7 pigmented rabbits, and fluidair exchange were done at the end of the surgery. Intraocular pressure was monitored by an air infusion system, and true IOP was measured by a transducer from the anterior chamber. Schiotz tonometry was done ar each 5mmHg IOP level, and the values were compared. Schiotz tonometry always gave a lower pressure, and the discrepancy seemed to be greater in aphakic eye, and when the heavier plunger weight were used. Conversion equation was suggested, and their reliability was discussed.
Anterior Chamber ; Intraocular Pressure* ; Manometry ; Operating Tables ; Rabbits ; Transducers ; Vitrectomy*

The patient was a 7 months old Korean girl, who was admitted to Department of Ophthalmology of the Seoul National University Hospital, with 6 months history of the left eyelid swelling and exophthalmos. Visual acuity and ocular movement were unaffected. Orbit CT revealed 1.5x.5 cm sized well circumscribed intraconal mass in the left retrobulbar space with pressure erosion of adjacent bone. At surgery, the mass was pinkish gray and firm, and was adherent to adjacent tissue. The whole mass could not be removed, and a local excision was done.

Advanced glycation end-product(AGE)is known as a factor causing diabetic retinopathy, but little is known about its effect on the function of outer blood-retinal barrier. To test whether AGE can increase the permeability of outer blood-retinal barrier, we injected glycated albumin into white rabbit eyes and observed the change of the fundus and of the outer blood-retinal barrier permeability. The rabbit retina in medullary ray was thickened in AGE-injected eyes. Intravenously injected microperoxidase, tracer molecule, was found in outer sensory retinal layer and outside of the retinal pigment epithelium in AGE-injected eyes. These results suggest that intraocularly injected AGE can increase the outer blood-retinal barrier permeability.
Blood-Retinal Barrier* ; Diabetic Retinopathy ; Permeability ; Retina ; Retinal Pigment Epithelium ; Retinaldehyde

We investigated the development of programmed cell death of apoptosis as a mechanism of cell death in experimental retinal vein occlusion of rats. We induced hemicentral retinal veinocclusion by photocoagulation 3 or 4 out of 6 retinal veins after infecting rose bengal intravenously.The eyes were enucleated sequentially between day one to day fourteen, and the retinas were examined after H&E and TUNEL staining. Exudative retinal detachment developed one day after vein occlusion and was reabsorbed completely by day 4. The number of ganglion cells in vein-occluded retina began to decrease one day after vein occlusion and continue to decrease until day fourteen. Many cells in ganglion cell layer and inner nuclear layer were stained positively by TUNEL staining. These results suggest that apoptosis is an important mechanism of cell death in early stage of experimental retinal vein occlusion.
Animals* ; Apoptosis ; Cell Death ; Ganglion Cysts ; In Situ Nick-End Labeling ; Ischemia ; Light Coagulation ; Models, Animal* ; Rats ; Retina ; Retinal Detachment ; Retinal Vein Occlusion* ; Retinal Vein* ; Retinaldehyde* ; Rose Bengal ; Veins

We used an animal model of laser-induced retinal vein occlusion to study the temporal and spatial patterns of neuronal necrosis and apoptosis. After photodynamic retinal vein thrombosis with argon-green laser, rats were sacrificed at 6 hours, 12 hours, 1 day, 2 days, 3 days, 5 days, 7 days, and 14 days after vein occlusion. The temporal and spatial patterns of neuronal cell death were determined using light and electron microscopy, TdT-dUTP nick-end labeling[TUNEL]and DNA gel electrophoresis. The cells in retinal ganglion cell layer and inner nuclear layer showed both necrotic and apoptotic changes 12 hours after vein occlusion. The TUNEL positivity were detected at day 1 after vein occlusion and the number of positive cell increased until day 2, and decreased thereafter. DNA ladder pattern was observed 48 hours after vein occlusion by DNA gel electrophoreisis. These data demonstrated that retinal vein occlusion induces necrosis and apoptosis in the retinal ganglion cell and inner nuclear layer.
Animals ; Apoptosis ; Cell Death* ; DNA ; Electrophoresis ; In Situ Nick-End Labeling ; Microscopy, Electron ; Models, Animal ; Necrosis ; Neurons ; Rats ; Retinal Ganglion Cells ; Retinal Vein Occlusion* ; Retinal Vein* ; Retinaldehyde* ; Veins

We used an animal model of laser-induced retinal vein occlusion to study the temporal and spatial patterns of neuronal necrosis and apoptosis. After photodynamic retinal vein thrombosis with argon-green laser, rats were sacrificed at 6 hours, 12 hours, 1 day, 2 days, 3 days, 5 days, 7 days, and 14 days after vein occlusion. The temporal and spatial patterns of neuronal cell death were determined using light and electron microscopy, TdT-dUTP nick-end labeling[TUNEL]and DNA gel electrophoresis. The cells in retinal ganglion cell layer and inner nuclear layer showed both necrotic and apoptotic changes 12 hours after vein occlusion. The TUNEL positivity were detected at day 1 after vein occlusion and the number of positive cell increased until day 2, and decreased thereafter. DNA ladder pattern was observed 48 hours after vein occlusion by DNA gel electrophoreisis. These data demonstrated that retinal vein occlusion induces necrosis and apoptosis in the retinal ganglion cell and inner nuclear layer.
Animals ; Apoptosis ; Cell Death* ; DNA ; Electrophoresis ; In Situ Nick-End Labeling ; Microscopy, Electron ; Models, Animal ; Necrosis ; Neurons ; Rats ; Retinal Ganglion Cells ; Retinal Vein Occlusion* ; Retinal Vein* ; Retinaldehyde* ; Veins

The course of experimental uveitis and inflammatory membrane proliferation was observed following intravitreal single injection of bacterial endotoxins (Escherichia coli, Salmonella typhimurium, Shigella flexneri). 30 microgram/O.1cc of one endotoxin was injected to 5 pigmented rabbits (total 15 rabbits), then the inflammatory processes of anterior chamber and vitreous cavity were evaluated and the histologic review was also made. Remarkable inflammatory signs were observed in 24-48 hours post-injection, decreased gradually, and disappeared in 1 week post-injection finally. The proliferation of vitreoretinal membrane was observed as early as in 2 weeks post-injection. In histologic examination, there were vitreal thickening, strand-like fibrous structure, and infiltration of spindle shaped cells and monocular cells in 2 weeks post-injection. The membrane, arising from the disc, was composed of the large vascular stalk, fibrous bundles, spindle shaped fibroblast-like cells, and round cells. In this results, the pathogenesis of intraocular membrane proliferation following intraocular inflammation could be understood more precisely.
Anterior Chamber ; Endotoxins ; Inflammation ; Membranes* ; Rabbits ; Salmonella typhimurium ; Shigella ; Uveitis

To determine surgical results and predictive factors of final visual acuity, a total of 30 eyes in 30 uveitis patients who underwent vitreous surgery including pars plana vitrectomy were followed for at least 6 months and various preoperative factors and postoperative results were analyzed. Our surgical indications were vitreous opacity, traction retinal detachment, combined rhegmatogenous-traction detachment. Preoperatively detached retina was finally reattached in 15 (83.3%) of 18 eyes. Final visual acuity improved in 19 (63.3%) of 30 eyes, but decreased in 3 eyes compared with the initial acuity. Cystoid macular edema was the main cause of poor visual acuity after surgery. Eyes with good final visual acuity showed relatively normal electroretinograms before surgery, but the relationship between them was not statistically significant. Duration of postoperative inflammation affected final visual acuity significantly. These results suggest that chronic uveitis patients with vitreoretinal complications can be managed by vitreous surgery with good anatomic and functional results.
Adolescent ; Adult ; Child ; Chronic Disease ; Eye Diseases/etiology/surgery ; Female ; Humans ; Male ; Middle Aged ; Prognosis ; Retinal Diseases/etiology/*surgery ; Uveitis/*complications ; Visual Acuity ; *Vitrectomy ; Vitreous Body/*surgery