Chemokines in aqueous humour before and after intravitreal triamcinolone acetonide in eyes with macular oedema associated with branch retinal vein occlusion

Purpose: To determine the aqueous humour levels of chemokines before and after an intravitreal injection of triamcinolone acetonide (IVTA) in eyes with macular oedema associated with a branch retinal vein occlusion (ME-BRVO). Design: Single-centre, prospective, consecutive interventional case series. Participants: Seventeen eyes of 17 consecutive patients with ME-BRVO who underwent IVTA were studied. Seven eyes without retinal vascular disease served as control. Intervention: All patients with ME-BRVO underwent IVTA. Main outcome measures: The optical coherence tomographically determined foveal thickness (FT) and the aqueous humour levels of inflammatory chemokines of the C-C subfamily, including eotaxin, monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), β (MIP-1β), and RANTES was determined before the IVTA (baseline) and at 1 week after the IVTA. Results: At the baseline, only MCP-1 and MIP-1β were detected in the aqueous, and MIP-1β was significantly higher in eyes with a ME-BRVO than in controls (p = 0.004). The level of both of these chemokines was not correlated with the FT (p = 0.654 and p = 0.608, respectively). One week after IVTA, the FT was significantly decreased (p < 0.001), and the levels of MCP-1 and MIP-1β were also significantly reduced (p < 0.001 and p = 0.044, respectively). The decrease in the FT was correlated with the decrease in only MIP-1β (r = 0.58, p = 0.020). Conclusions: Alterations of the aqueous level of MIP-1β reflect the improvement of the macular oedema after IVTA in eyes with ME-BRVO. This indicates that the steroid-dependent ME-BRVO was closely related with the level of MIP-1β.