Background: To evaluate the changes in aqueous vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) following intravitreal bevacizumab injections for choroidal neovascularization (CNV) secondary to age-related macular degeneration or pathologic myopia.
Methods: Aqueous samples were obtained at the time of injection from 51 eyes of 51 patients who underwent three monthly intravitreal bevacizumab (Avastin) injections at baseline, 1, and 2 months. Concentrations of VEGF and PEDF in the aqueous were evaluated using enzyme-linked immunosorbent assay and compared.
Results: For the 34 eyes with age-related macular degeneration CNV, the mean +/- standard deviation aqueous VEGF level reduced from 102.6 pg/mL +/- 90.6 pg/mL at baseline to 18.3 pg/mL +/- 22.5 pg/mL at 2 months (P < 0.001), whereas the mean PEDF level increased from 11.2 ng/mL +/- 10.4 ng/mL at baseline to 38.7 ng/mL +/- 47.9 ng/mL at 2 months (P = 0.001). For the 17 eyes with myopic CNV, the mean +/- standard deviation aqueous VEGF level reduced from 20.1 pg/mL +/- 28.9 pg/mL at baseline to 3.8 pg/mL +/- 5.3 pg/mL at 2 months (P = 0.016), whereas the mean PEDF level increased from 20.0 ng/mL +/- 16.3 ng/mL at baseline to 126.0 ng/mL +/- 152.0 ng/mL at 2 months (P = 0.016).
Conclusions: Intravitreal bevacizumab injections resulted in reduced aqueous VEGF and increased PEDF levels in patients with CNV secondary to age-related macular degeneration or pathologic myopia. These changes may be favorable for the inhibition of CNV angiogenesis.