本文研究为一个多中心、随机、对照的临床试验,以解决静脉分枝阻塞一些并发症的处理问题。本文报告讨论的问题是:光凝固能否改善视力下降到20/40以下的黄斑水肿眼的视力。将139例139眼分成四组,其中组Ⅲ为有黄斑水肿致视力下降危险的眼。其他组为最近静脉分枝阻塞发病3～18个月伴有视力降低至20/40以下,眼底荧光血管造影证实黄斑水肿,不存在中 This study was a multicenter, randomized, controlled clinical trial to address some of the complications of venous branching. The issue discussed in this report is whether photocoagulation improves visual acuity in eyes with macular edema below 20/40. 139 cases of 139 eyes were divided into four groups, of which group Ⅲ is the eye with the risk of decreased visual acuity due to macular edema. Other groups of recent venous occlusion morbidity 3 ~ 18 months with decreased visual acuity below 20/40, fundus fluorescein angiography confirmed macular edema, absent