Aqueous flare and inflammatory factors in macular edema with central retinal vein occlusion: a case series

BACKGROUND The association of inflammatory factors and the aqueous flare value with macular edema in central retinal vein occlusion (CRVO) patients remains unclear. We investigated the relations between the aqueous flare value and vitreous levels of vascular endothelial growth factor (VEGF), soluble intercellular adhesion molecule-1 (sICAM-1), and interleukin-6 (IL-6) in patients with CRVO and macular edema or patients with idiopathic macular hole (MH). METHODS In 38 patients who underwent unilateral vitrectomy (21 CRVO patients and 17 MH patients), vitreous samples were obtained during vitrectomy to measure VEGF, sICAM-1, and IL-6. Retinal ischemia was evaluated from capillary non-perfusion on fluorescein angiography, and the CRVO patients were classified into nonischemic or ischemic groups. Aqueous flare values were measured with a laser flare meter and macular edema was examined by optical coherence tomography. RESULTS The median aqueous flare value increased significantly across the three groups (MH group < nonischemic CRVO group < ischemic CRVO group). There was a significant correlation between the flare value and vitreous levels of VEGF, sICAM-1, and IL-6 in the CRVO group. The flare value was also significantly correlated with the severity of macular edema in the CRVO group. CONCLUSIONS Inflammation and/or ischemia may increase vascular permeability and disrupt the blood-aqueous barrier by increasing levels of inflammatory factors in patients with CRVO and macular edema.