The effect and opportunity of argon laser photocoagulation for the retinal neovascularization in branch retinal vein occlusion in 30 patients were investigated with a control group of 34 patients received nonlaser but routine treatment. The results of the therapeutic effect demonstrated that the neovascularization disappeared completely in 23 cases and became smaller in 7 cases after laser photocoagulation. The incidnce of vitreous hemorrhage in laser group was 43.3% before laser treatment and none after treatment in the duration of observation,and 70.6% in control group. The progression of visual acuity after treatment in laser group was much better than in control group(P<0. 005)at the time of the latest examination. We found the therapeutic effect was relation to the area, location of the neovascularization in retina,as well as whether the new vessels protruding into vitreous or not. (Chin J Ocul Fundus Dis,1994,10:195-198)
Severely coagulated retinae by argon laser of 20 Chinese hamsters were investigated with transmission electron-microscopy. The results revealed destruction of retinal pigment epithelium-Bruch's membrane-choroid capillary complex at the coagulated foci, and leakage of fluid and blood cells through the choroidal vessels into the subretinal space. Several days after laser burn the subretinal fluid was found to subside and the RPE cells surrounding the burned lesions started to proliferate. The smaller lesions were covered by the proliferating RPE 10 days after coagulation, but poor regeneration of RPE in large necrotic areas. Neovascularization was usually associated with obvious defect of Bruch's membrane and restoration of RPE barrier was most likely impossible. (Chin J Ocul Fundus Dis,1992,8:14-16)