Branch Retinal Vein Occlusion
Branch retinal vein occlusion (BRVO) is characterized by retinal hemorrhages in the territory of the obstructed vein. Macular edema, retinal ischemia and neovascularization can result, producing visual reduction.
BRVO usually occurs in patients in their fifth or sixth decades of life. The prevalence of BRVO in developed countries is estimated at just below 1%. There does not appear to be any racial or ethnic predilection. Systemic arterial hypertension is the most common systemic risk factor, present in about 75% of affected patients. The pathogenesis is believed to be disease of the adjacent arterial wall leading to venous compressesion at an arterovenous crossing point.
Patients may complain of visual blurring, distortion or metamorphopsia. On examination, intraretinal flame and blot shaped hemorrhages as seen in the territory of a dilated, tortuous retinal vein are present (Fig. 14.1.1