To evaluate clinical patterns according to the occlusion site in patients with branch retinal vein occlusion.

Ninety-one branch retinal vein occlusion patients were divided into 4 groups according to the occlusion site based on the description by Duke-Elder and Wybar: Papillary retinal vein occlusion group (group A), main retinal vein occlusion group (group B), minor retinal vein occlusion group (group C), and retinal venule occlusion group (group D). The following factors were analyzed retrospectively: baseline/final visual acuity, visual improvement, macular thickness, and macular circulatory states.

The macular thickness (µm) was 575.33 ± 178.44 in group A, 511.92 ± 218.02 in group B, 397.21 ± 144.51 in group C, and 336.68 ± 120.55 in group D. The retinal ischemic area (DD) was 22.00 ± 13.28 in group A, 18.26 ± 10.12 in group B, 12.52 ± 10.52 in group C, and 12.36 ± 11.92 in group D, which was found to be significantly greater in the group with the higher branch occlusion site ( p < 0.05). However, visual acuity, macular circulatory states and other clinical characteristics were not significantly different.

Occlusion site is a relating factor for retinal ischemic area and macular thickness in patients with Branch retinal vein occlussion, but which is not a prognostic factor for final visual acuity.