Effectiveness and cytokine profile of combined anti-vascular endothelial growth factor and corticosteroid therapy for chronic retinal vein occlusion

To investigate whether sub-Tenon injection of triamcinolone acetonide (STTA) combined with anti-vascular endothelial growth factor (VEGF) prolongs the recurrence intervals of macular edema (ME) for chronic retinal vein occlusion (RVO) and to investigate the differences in intraocular inflammatory cytokines between good responders (GRs) and non-responders (NRs). This retrospective, observational study involved 42 eyes of 42 patients with ME due to chronic RVO who had received only anti-VEGF for ≥ 1 year and were transitioned to combination therapy. GRs were defined as patients whose recurrence intervals were prolonged by ≥ 2 weeks compared with patients receiving anti-VEGF alone. Moreover, immediately before starting the combined therapy, aqueous humor was collected and the following inflammatory cytokines were compared between GRs and NRs: CCL11, MCP-3, IP-10, CCL13, G-CSF, GM-CSF, IL-1α, IL-15, IL-4, M-CSF, MMP-9, TNF-α, MCP-1, CXCL-1, CXCL12, IL-8, galectin-1, IFN-γ, IL-12, IL-2, IL-6, MMP-1, PDGF-AA, and VEGF-A. These results were analyzed by nominal logistic regression after stepwise variable selection. There were 26 eyes (62%) in the GR group. Nominal logistic analyses showed that a higher concentration of IL-1α (P = 0.016) and lower concentrations of IL-5 (P = 0.015), IL-6 (P = 0.022), and galectin-1 (P = 0.015) were significantly associated with the extension of the time from injection to recurrence of ME. Combined anti-VEGF and STTA therapy for chronic RVO was effective in 62% of patients, suggesting the effectiveness of STTA. Higher IL-1α and lower IL-5, IL-6, and galectin-1 were the factors associated with combined treatment effectiveness.