Intravitreal injection of autologous plasmin enzyme for macular edema associated with branch retinal vein occlusion.

PURPOSE: To investigate the effects of an intravitreal injection of autologous plasmin enzyme for macular edema associated with a branch retinal vein occlusion (BRVO). DESIGN: Prospective, interventional case studies. METHODS: Twenty-six eyes of 26 patients (14 men and 12 women) with macular edema resulting from a BRVO were studied. None of the eyes had a posterior vitreous detachment (PVD). The average age at the onset of BRVO was 58.7 ± 6.6 years. The interval between onset of the macular edema and injection of autologous plasmin enzyme was 4.2 months. One international unit of autologous plasmin enzyme in 0.1 mL was injected into each vitreous. The presence of a PVD was evaluated 1 week after the injection, and the visual acuity and macular thickness were measured before and 1 week and 1, 3, 6, and 12 months after the autologous plasmin enzyme injection. RESULTS: After the autologous plasmin enzyme injection, a total PVD was observed in 23 eyes and no PVD was observed in 3 eyes. The visual acuity gradually recovered after the injection, improved by 2 lines or more in 23 eyes, and remained unchanged in the 3 eyes. The retinal thickness also recovered gradually at 1, 3, 6, and 12 months. The mean retinal thickness was reduced from 602.12 to 253.62 µm at 12 months after surgery. It was reduced significantly after 1, 3, 6, and 12 months (P < .0001). CONCLUSIONS: Intravitreal autologous plasmin enzyme may lead to an improvement of visual acuity and a reduction of macula edema in eyes with BRVO.