Changes in aqueous cytokines after intravitreal triamcinolone versus bevacizumab for macular oedema in branch retinal vein occlusion

Abstract. Purpose: To investigate the changes in the aqueous levels of various cytokines after intravitreal triamcinolone or bevacizumab for branch retinal vein occlusion (BRVO). Methods: Twenty-four eyes with macular oedema associated with BRVO and six eyes of six patients undergoing cataract surgery participated in this study. Each patient with BRVO randomly received an intravitreal injection of either 4 mg triamcinolone or 1.25 mg bevacizumab. Aqueous samples were obtained before and 4 weeks after the intravitreal injection in the BRVO group and before surgery in the control group. Aqueous concentrations of 16 cytokines were measured via multiplex bead assay. Results: Prior to the administration of the drugs, aqueous levels of interleukin (IL)-6, IL-8, IL-17 and vascular endothelial growth factor (VEGF) were significantly higher in the BRVO group than in the control group (p = 0.044, p = 0.013, p < 0.001, and p = 0.008, respectively). Between the control group and the BRVO group, no significant differences were noted between pre- and postinjection best-corrected visual acuity (p = 0.60, p = 0.54) and central foveal thickness (p = 0.47, p = 0.82). In the triamcinolone group, levels of IL-6, IL-17, IP-10, platelet-derived growth factor (PDGF)-AA and VEGF were reduced significantly (p = 0.012, p < 0.001, p < 0.001, p = 0.015, and p < 0.001, respectively). But in bevacizumab group, only VEGF was significantly reduced (p < 0.001). Between the IVTA group and the IVBe group, no significant differences in the changes in VEGF levels were noted (p = 0.06). Conclusion: Triamcinolone injection reduces plural inflammatory cytokines in BRVO, while bevacizumab has no influence on other cytokines as selective anti-VEGF therapy. No differences in the therapeutic effect were noted between an inhibition of plural inflammatory cytokines and an inhibition of VEGF only.