fibrin and Eye-Hemorrhage

To determine the efficacy of a specific antithrombin agent (recombinant desulphatohirudin variant 1 [Revasc, Ciba-Geigy, Ltd., Basel, Switzerland]) administered in the infusion fluid to prevent early postoperative fibrin formation in a rabbit lensectomy and vitrectomy model.. Standard fragmatome lensectomies and core vitrectomies were performed prospectively in a masked fashion on ten control eyes with lactated Ringer's infusion and on ten eyes treated with 10 microgram of recombinant hirudin/ml in the infusate. The amounts of fibrin and hemorrhage were graded in a masked fashion by using slit-lamp examination and indirect ophthalmoscopy on postoperative days 1 through 5 and on day 7.. The difference in the mean grade of fibrin formed on the first postoperative day in the eyes treated with recombinant hirudin (mean, 0.9) in relation to the mean grade of fibrin in the control eyes (mean, 3.5) was statistically significant (P = .004). This difference was also significant on the second postoperative day (P = .01). None of the treated eyes developed intraoperative or postoperative hemorrhage.. Recombinant desulphatohirudin variant 1 is an effective inhibitor of postoperative fibrin formation in a rabbit model and is not associated with an increased risk of intraoperative or postoperative bleeding at the tested dose. This drug may be a useful adjunct in vitreous surgery for both proliferative vitreoretinopathy and the complications of proliferative diabetic retinopathy.

Topics: Animals; Antithrombins; Disease Models, Animal; Eye Hemorrhage; Fibrin; Fibrinolysis; Fibrinolytic Agents; Hirudin Therapy; Lens, Crystalline; Postoperative Complications; Prospective Studies; Rabbits; Recombinant Proteins; Thrombolytic Therapy; Vitrectomy

Local ocular hypothermia was evaluated in experimental open sky vitrectomy, closed vitrectomy, and anterior chamber irrigation and aspiration in 40 albino rabbits (80 eyes). The irrigating balanced salt solution was used at room temperature in control eyes and was cooled to 7 degrees C in experimental eyes. Experimental eyes demonstrated less intraocular bleeding volume, less fibrin production, and less postoperative inflammation. No detectable tissue intolerance to hypothermia was observed on short- or long-term follow-up.

Topics: Animals; Anterior Chamber; Eye Hemorrhage; Fibrin; Hypothermia, Induced; Inflammation; Postoperative Complications; Rabbits; Retinal Diseases; Retinal Hemorrhage; Vitrectomy