目的：比较早期行氪激光视网膜光凝治疗视网膜分支静脉阻塞和晚期激光治疗的疗效。 方法：视网膜分支静脉阻塞患者125例125眼分为早期治疗组68例68眼和晚期治疗组57例57眼，初诊时行视力、眼压、眼底、FFA和OCT检查。早期组在初诊时行氪激光光凝治疗：除出血区行氪红激光和波及黄斑区行氪黄激光，其余行氪绿激光，激光术后给予球后注射曲安奈德40mg。晚期组在初诊时口服沃丽汀、维生素Ｃ和安多明等药物，若病变波及黄斑区引起黄斑水肿者行球后注射曲安奈德40mg。1，3，6，12mo行复诊，复诊时行视力、眼压、眼底、FFA和OCT检查。若FFA检查发现晚期组视网膜出现毛细血管无灌注区行氪激光光凝治疗。随访时间为1a。 结果：早期组68眼中视力提高49眼（72.1％），视力稳定16眼（23.5％），视力下降3眼（4.4％）；晚期组57眼中视力提高35眼（61.4％），视力稳定8眼（14.0％），视力下降14眼（24.6％）。FFA和OCT检查发现早期组黄斑水肿消失或减轻的时间比晚期组明显缩短，视网膜出血吸收的时间也比晚期组缩短。早期组中没有1眼发生黄斑囊样变性、黄斑裂孔和玻璃体出血，晚期组中有14眼发生黄斑囊样变性或黄斑裂孔，有9眼发生玻璃体出血导致视力显著下降。 结论：早期行氪激光视网膜光凝治疗视网膜分支静脉阻塞的疗效明显优于晚期激光治疗，早期治疗能最大限度保存和提高患者的视力。早期行激光治疗未发现明显的不良反应，是安全有效的方法。

AIM:To observe the effect of later laser photocoagulation for the treatment of the branch retinal vein occlusion (BRVO) at the early and late stage. METHODS:Totally 125 cases (125 eyes) with BRVO were divided into two groups:a early therapeutic group of 68 cases (68 eyes) and a later therapeutic group of 57 cases (57 eyes). Visual acuity, intraocular pressure (IOP), fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) were recorded before therapy. The early therapeutic group was treated with krypton laser photocoagulation at baseline: krypton red laser was applied to obvious hemorrhage areas, krypton yellow laser was applied to obvious macular edema, krypton green laser was applied to the rest,retrobulbar TA at the dose of 40 mg was injected after laser photocoagulation. The later therapeutic group was treated with peroral drugs such as jolethin, vitaminC, calcium dobesilate in 1-3 months, retrobulbar TA at the dose of 40mg was injected in obvious macular edema. According to the capillary nonperfusion area showed by OCT and FFA at follow-up visits, the laser photocoagulation was applied.The follow-up was 1 year. RESULTS:In early therapeutic group of 68 eyes, visual acuity was improved in 49 eyes(72.1%), stable in 16 eyes(23.5%), and decreased in 3 eyes(4.4%). In later therapeutic group of 57 eyes, visual acuity was improved in 35 eyes(61.4%), stable in 8 eyes(14.0%), and decreased in 14 eyes(24.6%). The course of reduction or elimination of macular edema of early therapeutic group was significantly shorter than that of later therapeutic group, the rate of cystoid macular degeneration and macular hole were pretty reduced, the course of absorption of retinal hemorrhage of early therapeutic group was shorter than that of control group. No eye of cystoid macular degentation, macular hole or vitreal hemorrhage was noted in early therapeutic group,but 14 eyes occurred cystoid macular degeneration or macular hold, 9 eyes of vitreal hemorrhage caused decrease of visual acuity in later therapeutic group. CONCLUSION:The treating efficacy of early laser photocoagulation for the treatment of the BRVO was better than that of later laser photocoagulation,as it can maintain the visual functions uttermostly.Laser photocoagulation can promote the absorption of retinal hemorrhage, reduction or elimination of macular edema, prevention of cystoid macular degeneration, prevention of retinal neovascularization and vitreal hemorrhage. No adverse events following early laser photocoagulation treatment were observed.