Purpose: To investigate the correlation between angiotensin II (AII) or vascular endothelial growth factor (VEGF) levels in the vitreous fluid and the severity of diabetic macular edema (DME).
Design: A case-control study.
Methods: Vitreous fluid samples were obtained at the time of vitreoretinal surgery from 20 eyes of 20 patients with DME, 6 eyes of 6 diabetic patients without retinopathy, and 14 eyes of 14 nondiabetic patients. The VEGF levels in vitreous fluid and plasma were determined by enzyme-linked immunosorbent assay, while AII levels were measured by radioimmunoassay.
Results: The vitreous concentration of VEGF was significantly higher in patients with DME than in nondiabetic patients or diabetic patients without retinopathy (P <.0001 and P <.0001, respectively). Vitreous levels of AII were also higher in patients with DME than in nondiabetic patients (P =.0082). The vitreous concentration of AII was significantly correlated with that of VEGF (P =.0022). Vitreous concentrations of both AII and VEGF were significantly higher in patients with hyperfluorescent DME than in those with hypofluorescent (P =.0228 and P =.0068, respectively).
Conclusions: We found that the levels of both AII and VEGF were elevated in the vitreous fluid of patients with hyperfluorescein DME. Our results suggest that both AII and VEGF are related to the increase of vascular permeability in DME.