This study aimed to quantitate and compare the concentration of vascular endothelial
growth factor (VEGF) in aqueous humor samples from patients with neovascular glaucoma
(NVG), primary open-angle glaucoma (POAG), and cataract, as well as in serum samples
of healthy human subjects.
The authors collected aqueous humor samples by using their previously published technique
of limbal paracentesis. The authors determined the concentration of VEGF by using
a competitive enzyme immunoassay system and four-parameter logistic curve fitting
and performed statistical analysis by using the Mann-Whitney-Wilcoxon test.
The authors detected VEGF in 12 of 12 samples from patients with NVG (mean +/- standard
error of the mean, 29.267 +/- 7.350 ng/ml), 15 of 28 samples from patients with POAG
(0.726 +/- 0.204 ng/ml), 4 of 20 aqueous humor samples from patients with cataract
(0.257 +/- 0.043 ng/ml), and 16 of 16 human serum samples (20.246 +/- 1.568 ng/ml).
The mean concentration of VEGF in aqueous humor of patients with NVG was 40- and 113-fold
higher than that in patients with POAG and cataract, respectively, and the difference
was statistically significant (P < 0.01). The VEGF level in patients with POAG was
elevated compared with that in patients with cataract (P < 0.05). Although the mean
concentration of VEGF in aqueous humor of patients with NVG was approximately 1.45-fold
higher than that in serum, the difference was not significant (P > 0.05).
The authors' findings show that patients with NVG had a significantly increased level
of VEGF in the aqueous humor and implicate VEGF as an important factor in the pathogenesis
of intraocular neovascularization in these patients. The authors discuss the possible
role of the ciliary epithelium, in addition to retina, in the production of VEGF and
the complementary function of basic fibroblast growth factor and other growth factors.