Abstract
Purpose :
We sought to explore the relationship between choriocapillaris perfusion and vascular complexity of choroidal neovascular membranes (CNV). We used optical coherence tomography angiography (OCTA) to test the hypothesis that more complex, multi-layered CNV patterns in age-related macular degeneration (AMD) were correlated with reduced blood flow signal in the choriocapillaris.
Methods :
We used automated OCTA software (version 2017.1.0.151) to measure choriocapillaris vessel density (%) in the parafoveal sectors outside the CNV region. We also calculated percent choriocapillaris area of nonperfusion (PCAN) outside the CNV (total-PCAN) and within a 200 µm anulus around the CNV (halo-PCAN). We used projection resolved OCTA to assess CNV complexity parameters, including greatest CNV flow height above Bruch’s membrane, number of flow layers and average thickness between flow layers. We used Pearson r tests to compare choriocapillaris perfusion with CNV complexity.
Results :
Our initial pilot analysis included 10 of total 40 recruited eyes (9/10 females; mean age 73.9 ± 14.3 years). All were previously treated eyes with a mean of 9.8 ± 12.8 anti-vascular endothelial growth factor injections. We found that greater thickness between CNV flow layers was significantly correlated with reduced choriocapillaris vessel density outside the CNV (r=-0.617; p=0.029). Other CNV complexity parameters showed nonsignificant trends with vessel density and PCAN.
Conclusions :
These preliminary results prompt us to complete this study of all 40 eyes, using OCTA to explore the relationship between the choriocapillaris and CNV complexity. The study will be critical in further clarifying the relationship between neovascular AMD lesion complexity and the surrounding choriocapillaris, which could provide important insights regarding vascular perfusion deficits in the choroid around these potentially high flow, complex lesions.
This is a 2020 ARVO Annual Meeting abstract.