Abstract
Purpose: :
Combination treatment with anti-VEGF agents and photodynamic therapy (PDT) is used in the treatment of exudative age related macular degeneration (AMD). Aqueous VEGF levels have shown correlation with disease activity in exudative AMD. The aim of this study is to examine correlation between aqueous VEGF levels in exudative AMD patients treated with anti-VEGF agent, bevacizumab, initially and subsequent change, if any, observed after treating with PDT.
Methods: :
Retrospective observational case series of 10 patients undergoing anti-VEGF therapy with intravitreal bevacizumab for newly diagnosed or recurrent choroidal neovascular membrane (CNV), who underwent reduced fluence PDT, due to persistent disease activity after treatment with 3 injections of bevacizumab (initial phase). Aqueous samples were obtained prior to first intravitreal injection of bevacizumab (Pre-Sample), with subsequent samples collected prior to each injection (Post-Sample). A final sample of aqueous was obtained 4 to 6 weeks following PDT (Post PDT-Sample). Aqueous VEGF levels were determined using bead based assay (Luminex). Mean VEGF levels after each injection of bevacizumab and after PDT was calculated and compared to note any difference. Statistical analysis was conducted using the Mann-Whitney test.
Results: :
The mean Pre-Sample VEGF level in the aqueous was 363 + 29.2 pg/ml. The percentage decrease, compared with pre-sample, in aqueous VEGF levels after 3 intravitreal injections of bevacizumab was 33 + 6.7 %( p=0.04). The percentage decrease, compared to pre-sample, of aqueous VEGF level after PDT was 21.8 + 2.1 % (p=0.05).
Conclusions: :
In patients with exudative AMD, resistant to treatment with sequential intravitreal bevacizumab, combination treatment with intravitreal bevacizumab and PDT resulted in further significant decrease in aqueous VEGF levels.
Keywords: age-related macular degeneration • vascular endothelial growth factor • photodynamic therapy