Purpose: To investigate the difference in intraocular vascular endothelial growth factor (VEGF) concentration between pachychoroid neovasculopathy and neovascular age-related macular degeneration (nAMD) and its associations with responses to three monthly anti-VEGF injections as an initial treatment for the two conditions.
Methods: This study included nine eyes with treatment-naïve pachychoroid neovasculopathy and 21 eyes with treatment-naïve nAMD. Before the initial intravitreal anti-VEGF injection, aqueous humor samples were collected and the concentration of VEGF was measured using enzyme-linked immunosorbent assay. The concentration was compared between the two conditions, and its associations with responses to anti-VEGF therapy were investigated.
Results: The mean VEGF concentration in pachychoroid neovasculopathy was significantly lower than that in nAMD (63.4 ± 17.8 pg/ml and 89.8 ± 45.0 pg/ml, respectively; P = 0.035). The VEGF concentration was associated with the presence or absence of drusen (β = 0.503, P = 0.004). After anti-VEGF therapy, 6 (66.7%) of 9 eyes with pachychoroid neovasculopathy and 17 (81.0%) of 21 eyes with nAMD achieved dry macula (P = 0.640). Dry macula at 3 months and 12 months was significantly associated with a low VEGF concentration in pachychoroid neovasculopathy (P = 0.013 and P = 0.042, respectively), but not in nAMD (P = 0.108 and P = 0.219).
Conclusions: The mean VEGF concentration in pachychoroid neovasculopathy was lower than that in nAMD, suggesting that the way in which VEGF is involved in angiogenesis may differ between pachychoroid neovasculopathy and nAMD.