Laser-induced chorioretinal venous anastomosis for nonischemic central or branch retinal vein occlusion

Objective: To establish a communication between an obstructed retinal vein and the choroid by means of laser in eyes with nonischemic central or branch vein occlusion. Methods: Retrospective review identified eyes with nonischemic central or branch vein occlusion, and with decreasing or persistently decreased visual acuity of 20/100 or worse for 4 months or more before treatment, that received 1 or more sessions of:laser photocoagulation to create a chorioretinal anastomosis. Results: Of 24 eyes with central vein occlusion, an anastomosis formed in 9 (38%) within 2 months after treatment, with visual improvement of 6 or more lines in 2 (8%) of 24 eyes, I to 3 lines in 5 (21%), and no improvement in 2 (8%). Of 6 eyes with branch vein occlusion, an anastomosis formed in 3 (50%) within 2 months after treatment, with visual improvement of I to 3 lines in 2 (33%) of 6 and no improvement in 1 (16%). No permanent, vision-limiting complications occurred during a mean follow-up of 13 months after the first treatment session or 8 months after the last session. Conclusions: Laser photocoagulation of a retinal vein and Bruch's membrane may create a chorioretinal anastomosis in some eyes with a nonischemic vein occlusion. Progression to an ischemic status may possibly be prevented with successful anastomosis formation. Marked visual improvement may occur. Treatment techniques to create reliably an anastomosis with subsequent visual improvement, while minimizing potential complications, continue to evolve.