Abstract
Purpose::
To study the concentration of vascular endothelial growth factor (VEGF) in the aqueous humor before and after injection of intravitreal bevacizumab to treat proliferative diabetic retinopathy.
Methods::
Bevacizumab (1.25 mg/0.05 ml) was injected into the vitreous cavity as a preoperative adjunctive therapy 1 week before pars plana vitrectomy for proliferative diabetic retinopathy in 14 eyes of 12 cases. Aqueous humor samples were obtained just before injection of intravitreal bevacizumab and just before vitrectomy. The VEGF concentration in the aqueous humor was measured by enzyme-linked immunosorbent assay.
Results::
The VEGF concentration in the aqueous humor ranged from 159 to 676 pg/ml (mean, 346±137) before intravitreal bevacizumab injection and decreased to less than 31 pg/ml (measuring limit) (Wilcoxon signed rank test, P < 0.001) in all cases 1 week after the injection.
Conclusions::
Intravitreal bevacizumab injections resulted in a significant decrease in the VEGF concentration in the aqueous humor.
Keywords: diabetic retinopathy • aqueous