The correlation between cytokine levels in the aqueous humor and the prognostic value of anti-vascular endothelial growth factor therapy for treating macular edema resulting from retinal vein occlusion.

Purpose: To determine the correlation between aqueous humor cytokine levels and the prognostic value of anti-vascular endothelial growth factor (VEGF) therapy for treating macular edema resulting from retinal vein occlusion (RVO-ME).

Methods: This prospective study included 47 RVO-ME and 32 senile cataract cases. Aqueous humor collection was performed in patients with RVO-ME before intravitreal injection of ranibizumab and in patients before cataract surgery. VEGF, monocyte chemotactic protein 1 (MCP-1), interleukin (IL)-8, IL-6, basic fibroblast growth factor (b-FGF), and tumor necrosis factor-α (TNF-α) levels were measured in the aqueous humor. Central retinal thickness (CRT) was measured before ranibizumab treatment and during each follow-up visit. The recovery rate following ranibizumab treatment was calculated as (CRT-CRT)/CRT, in which CRT was the CRT measured before treatment and CRT was measured 1 week after treatment. The recurrence time of RVO-ME was recorded.

Results: VEGF, MCP-1, IL-8, and IL-6 levels in the aqueous humor of patients with RVO-ME were significantly higher compared with control and were positively correlated with the CRT. Ranibizumab significantly reduced CRT, and VEGF levels positively correlated with the recovery rate. The mean recurrence time of RVO-ME was 43.5 days. IL-6 levels negatively correlated with the recurrence time of ME.

Conclusion: VEGF, MCP-1, IL-8, and IL-6 levels were significantly increased in patients with RVO-ME and were positively correlated with ME. Higher VEGF levels were indicative of CRT recovery, and higher IL-6 levels were indicative of ME recurrence after ranibizumab treatment.