Volume-rendering three-dimensional image analysis of macular neovascularization in age-related macular degeneration

To visualize and investigate the three-dimensional (3D) images of macular neovascularization (MNV) in eyes with neovascular age-related macular degeneration using optical coherence tomography angiography (OCTA) according to the treatment response to intravitreal aflibercept injection (IVI).

OCTA images at baseline and 12 weeks (after three loading IVIs) were retrospectively reconstructed as 3D images for patients with type 1 and 2 MNV treated with the "pro-re-nata" regimen. The fluid-free and persistent fluid groups were divided according to the presence of subretinal and intraretinal fluid at 12 weeks after treatment. Using reconstructed 3D images of MNV, the volume, average volume per slice, and z-axis of the volumetric structure were evaluated.

Twenty-three and nine were classified into the fluid-free and persistent fluid groups, respectively. The MNV volume decreased significantly from baseline to 12 weeks in the fluid-free group (p = 0.005), not in the persistent fluid group (p = 0.250). The average volume of MNV per slice at 12 weeks correlated with the persistent fluid group in both the univariate and multivariate analyses (p = 0.034, p = 0.039, Exp [B] = 14.005).

This study may provide a perspective on vascular volumetric changes of MNV according to treatment response.