Aqueous levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) are associated with the severity of macular edema in patients with central retinal vein occlusion (CRVO). We investigated whether aqueous and vitreous levels of these molecules were correlated in CRVO patients.
Methods.
Aqueous and vitreous samples were obtained during cataract surgery and vitreous surgery from 17 patients (17 eyes) with CRVO and macular edema. The levels of VEGF and IL-6 in aqueous humor, vitreous fluid, and plasma were determined by enzyme-linked immunosorbent assay.
Results.
The aqueous levels of VEGF and IL-6 were significantly correlated with the vitreous levels of these molecules (ρ=0.8799, p=0.0004 and ρ=0.8088, p=0.0012, respectively). Vitreous levels of VEGF and IL-6 were significantly higher in CRVO patients with retinal ischemia than in those without ischemia (p=0.0013 and p=0.0009, respectively), as were the aqueous levels of VEGF and IL-6 (p=0.0026, p=0.0120, respectively). Furthermore, both the aqueous and vitreous levels of VEGF and IL-6 were significantly correlated with the severity of macular edema (ρ=0.7181, p=0.0041; ρ=0.8260, p=0.0010; ρ=0.5564, p=0.0260; and ρ=0.6599, p=0.0039, respectively).
Conclusions.
Our results suggest that aqueous levels of VEGF and IL-6 may reflect the vitreous levels of these molecules. Measurement of VEGF and IL-6 in the aqueous humor may be clinically useful to assess the severity of macular edema in patients with CRVO.
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