Role of inflammation in diabetic macular edema

Vitreous fluid levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor (sVEGFR)-2, soluble intercellular adhesion molecule (sICAM)-1, monocyte chemotactic protein (MCP)-1 and pentraxin 3 (PTX3) were measured by enzyme-linked immunosorbent assay in 36 patients with diabetic macular edema (DME) and 15 patients with macular hole (MH). Aqueous flare values were measured with a laser flare meter, and macular edema was examined by optical coherence tomography. Vitreous fluid levels of VEGF, sVEGFR-2, sICAM-1, MCP-1 and PTX3 were significantly higher in the patients with DME than in those with MH. There was a significant correlation between the vitreous fluid level of sVEGFR-2 and the levels of sICAM-1, MCP-1 and PTX3. The aqueous flare value was significantly correlated with the vitreous fluid levels of sVEGFR-2, sICAM-1, MCP-1 and PTX3. These findings suggest that inflammatory factors may induce an increase in vascular permeability and disrupt the blood-aqueous barrier in DME patients.