Argon laser photocoagulation for macular edema in branch vein occlusion.

The Branch Vein Occlusion Study is a multicenter, randomized controlled clinical trial that was designed to answer several questions regarding the management of complications of branch vein occlusion. Recently, this study reported the benefit of argon laser photocoagulation for improving visual acuity in certain eyes with macular edema, performing the laser photocoagulation in a "grid" pattern over the area demonstrated as leaking by fluorescein angiography. Comparing treated patients with control patients (mean follow-up 3.1 years for all study eyes), a gain of at least two lines of visual acuity from baseline maintained for two consecutive visits was significantly greater in treated eyes (P = 0.00049 log rank test). Because of this improvement in visual acuity with argon laser photocoagulation, the study recommends laser photocoagulation for patients with macular edema associated with branch vein occlusion who meet the eligibility criteria of the study.