Serous macular detachment in branch retinal vein occlusion

PURPOSE: To evaluate the relationship between the extent of branch retinal vein occlusion (BRVO) and the incidence of serous retinal detachment (SRD) in the macular area. METHODS: One hundred nine eyes of 109 consecutive patients with BRVO comprised the study population. These eyes were characterized as having either macular BRVO or major BRVO. We compared the tomographic macular findings between the two groups. RESULTS: Thirty-nine eyes had macular BRVO, and 70 eyes had major BRVO. The incidence of SRD was higher in the group with major BRVO (63%) than in the group with macular BRVO (21%) (P < 0.001). The incidence of cystoid macular edema was similar in both groups (macular BRVO, 97%; and major BRVO, 90%). Foveal thickness of major BRVO (610 +/- 190 micro m) was significantly greater than that of macular BRVO (500 +/- 140 micro m) (P < 0.01). There was no significant difference in thickness of the neurosensory retina between the group with macular BRVO (450 +/- 120 micro m) and the group with major BRVO (480 +/- 140 micro m). CONCLUSIONS: Serous macular detachment occurs more frequently in major BRVO than in macular BRVO. Vascular leakage from congested retinal veins outside the macular area appears to be a major source of subretinal fluid at the fovea.