Epiretinal Macrophage-Like Cell Alterations Following Anti-VEGF Therapy in Branch Retinal Vein Occlusion with Macular Edema: A Retrospective Longitudinal Study

Purpose: To investigate the impact of anti-vascular endothelial growth factor (anti-VEGF) therapy on epiretinal macrophage-like cells (eMLC) in BRVO-ME patients. Methods: This retrospective study included 58 BRVO-ME patients treated with anti-VEGF agents, divided into two groups: 28 eyes (1-2 Injection group) and 30 eyes (3 Injection group). The 3-injection group comprised 20 early responders (ERs) and 10 limited early responders (LERs). Longitudinal changes in macular eMLC count and density were assessed via En face OCT during the early response phase (baseline to 3 months post-initial injection). Linear regression and Spearman correlation analyzed eMLC density's relationship with OCTA parameters and systemic inflammatory indices. Results: The 3-injection group exhibited greater reductions in macular edema and eMLC density than the 1-2 injection group. Macular eMLC density significantly decreased in ERs, while LERs showed no significant alteration. Post-treatment CMT change positively correlated with eMLC density change (r=0.57). Baseline systemic inflammatory indices (NLR, r=-0.46; NPR, r=-0.36; SII r=-0.33; SIRI, r=-0.31;) negatively correlated with post-treatment eMLC density change. Conclusion: Anti-VEGF therapy reduces macular eMLC in BRVO-ME patients, especially in early responders receiving three injections. Macular eMLC are closely associated with inflammation and may serve as a valuable treatment response biomarker.