BackgroundTo explore the impact of anti-vascular epithelial growth factor (ant-VEGF) on the thickness of each retinal layer in patients with macular edema (ME) secondary to the branch retinal vein occlusion (BRVO).MethodsThis retrospective study included patients with ME secondary to monocular BRVO who received anti-VEGF therapy in Ningxia Eye Hospital between January-December 2020.ResultsForty-three patients (25 males) were included, with 31 showed > 25% reduction in central retinal thickness (CRT) after anti-VEGF therapy (response group), and the others showed a ≤25% reduction in CRT (no-response group). The response group showed significantly smaller mean changes in the ganglion cell layer (GCL) (after 2 months) and inner plexiform layer (IPL) (after 1, 2, and 3 months) and significantly greater mean changes in the inner nuclear layer (INL) (after 2 and 3 months), outer plexiform layer (OPL) (after 3 months), outer nuclear layer (ONL) (after 2 and 3 months), and CRT (after 1 and 2 months) (all P < 0.05) as compared to the no-response group. The mean change in the thickness of each retinal layer IPL (P = 0.006) between the two groups was significantly different after controlling for a time and with a significant time trend (P < 0.001). Additionally, patients in the response group were more likely to have an improvement in IPL (43.68 ± 6.01 at 1 month and 41.52 ± 5.45 at 2 months vs. 39.9 ± 6.86 at baseline) after anti-VEGF therapy, while those in no response group might show improvement in GCL (45.75 ± 8.24 at 1 month, 40.00 ± 8.92 at 2 months, and 38.83 ± 9.93 at 3 months vs. 49.67 ± 6.83 at baseline).ConclusionsAnti-VEGF therapy might help restore the retinal structure and function in patients with ME secondary to BRVO, and those who have a response after anti-VEGF therapy are more likely to improve IPL, while those having no response might show improvement in GCL.