CHOROIDAL MORPHOLOGY IN EYES WITH PERIPAPILLARY POLYPOIDAL CHOROIDAL VASCULOPATHY.

This study analyzes a subset of patients with peripapillary polypoidal choroidal vasculopathy (PCV) to determine whether quantifiable pachychoroid features colocalize with disease foci. Patients with PCV diagnosed by indocyanine green angiography were identified for the analysis of medical records and multimodal imaging and classified as having peripapillary or macular PCV. The ratio of Haller layer thickness to total choroidal thickness was calculated at the fovea and at the site of dilated Haller vessels that showed spatial correlation with the origin of neovascularization. Choroidal thickness was measured horizontally across the fovea and circumferentially around the temporal side of the disk to study its relationship to neovascularization. Three hundred and fourteen eyes of 299 patients with PCV were identified, of which 17 eyes (5%) had peripapillary disease. Although eyes with peripapillary PCV exhibited thinner subfoveal choroids than those with macular PCV, at the extrafoveal disease foci, choroidal thickness, Haller's layer thickness, and its ratio to total choroidal thickness were relatively high. Quantitative indices of choroidal structure previously identified in macular PCV performed consistently when applied to a peripapillary PCV cohort, thus supporting the hypothesis that inner choroidal thinning and Haller vessel enlargement are mechanistically relevant to these related entities.