Arteriovenous sheathotomy for branch retinal vein occlusion.

Branch vein occlusion is a significant cause of visual loss attributed to retinal vascular disease and is second only to diabetic retinopathy. BVO nearly always occurs at an AV crossing because of compression of the vein by the artery, resulting in hemodynamic abnormalities in the vein, including thrombus formation, reversal of flow toward the artery, and AV collateral formation. Relatively little information is available on the natural history of BVO; most of what exists is derived from clinical trials, including the BVOS. Current treatment options focus on treating sequelae of the occluded venous branch, such as macular edema, retinal neovascularization, vitreous hemorrhage, and traction retinal detachment. A novel therapeutic approach is decompression of the AV crossing, which has had promising initial results including restoration of vision and reversal of hemodynamic abnormalities. A prospective, controlled, clinical trial is being organized to determine the role of AV sheathotomy in the treatment of BVO.