Abstract
Purpose :
Using optical coherence tomography angiography (OCTA), we tested the hypothesis that baseline choriocapillaris flow deficits surrounding treatment-naïve choroidal neovascular membranes (CNV) correlate with the number of subsequent anti-vascular endothelial growth factor (VEGF) injections during the course of treatment for age-related macular degeneration (AMD).
Methods :
We used a semi-automated method to compensate for focal and global signal attenuation of the treatment-naïve choriocapillaris. We then binarized the choriocapillaris using the local Phansalkar and global MinError(I) methods. We quantified flow deficit density (FDD) in the 200 µm annulus surrounding the dark halo of the CNV and the entire area outside the dark halo of the CNV. We used Pearson r and t-tests to compare FDD at baseline with number of anti-VEGF injections received from 6 to 12 months and 12 to 24 months after starting therapy
Results :
Our initial analysis included 9 eyes of 9 patients (6 females; age 69.9 ± 5.7 years). The number of anti-VEGF injections, which ranged from 1 to 6 over the subsequent 6 to 12 months, was significantly correlated with greater baseline FDD in the annulus (Phansalkar, r=0.797, p=0.005; MinError(I), r=0.690, p=0.020). When assessing injections received between 6 and 12 months, eyes that received higher number of injections (n=5, 4-6 injections) had higher FDD in the annulus and entire area around the dark halo (Phansalkar, p<0.05) compared to the low injection group (n=4, 1-2 injections). These relationships showed a trend using MinError(I) (both p>0.05). No tests were significant for number of injections between 12 and 24 months.
Conclusions :
The study highlights the importance of the choriocapillaris during the pathogenesis of neovascular AMD. Our results suggest an early influence for choriocapillaris deficiency on treatment response between 6 and 12 months, but more subjects are needed to confirm these results.
This is a 2021 ARVO Annual Meeting abstract.