CHOROIDAL VASCULAR ALTERATIONS IN AGE-RELATED MACULAR DEGENERATION AND POLYPOIDAL CHOROIDAL VASCULOPATHY

In eyes with neovascular age-related macular degeneration and polypoidal choroidal vasculopathy, choroidal veins frequently show variation in vessel caliber and focal constrictions. Together with dilated intervortex anastomotic segments, these morphologic alterations suggest that atherosclerosis and venous insufficiency may contribute to the pathogenesis of these conditions. Purpose: To evaluate morphologic alterations in choroidal veins in eyes with typical neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV). Methods: A retrospective review of baseline indocyanine green angiography in eyes with typical nAMD and PCV. We evaluated Haller layer veins in the early-phase indocyanine green angiography (before 2 minutes) for 1) macular anastomosis, 2) dilated Haller veins, and 3) focal variation in vessel caliber by at least 50% from the narrowest to largest diameters. Results: We included 70 patients with gradable indocyanine green angiography for the prespecified features in the study eye (36 typical nAMD and 34 PCV) and 59 fellow eyes. The median subfoveal choroidal thickness was 167 µm versus 219 µm, P = 0.08, in the presenting eyes in typical nAMD and PCV, respectively. Macular anastomosis was common in both typical nAMD and PCV (presenting eyes 58.3% vs. 58.8%. P = 0.97; fellow eyes 65.5% vs. 63.3%, P = 0.86). Dilated Haller veins were numerically less common in typical nAMD than PCV (presenting eyes 52.8% vs. 67.6%, P = 0.21; fellow eyes 65.5% vs. 70.0%, P = 0.71), while vascular caliber variation was numerically more common in typical nAMD than PCV (presenting eyes 72.2% vs. 63.8%, P = 0.45; fellow eyes 69.0% vs. 56.7%, P = 0.33). The presence of all three features was more common in the presenting eyes with PCV compared with typical nAMD (35.3% vs. 13.9%, P = 0.03). In a multivariable analysis, every increase of 100 µm of CT conferred a 2.75 risk of having all three features present. Conclusion: Choroidal vascular remodeling is common in both tAMD and PCV but may be driven by different stimuli.