Pigment epithelium and choroid changes in pachychoroid pigment epitheliopathy: A descriptive study

Purpose: To describe characteristic elementary lesions of retinal pigment epithelium and choroidal vascular parameters determined by swept source optical coherence tomography (SS‐OCT) and OCT‐angiography (OCT‐A) in eyes with pachychoroid pigment epitheliopathy. Methods: Twenty‐seven patients with retinal pigment epithelium (RPE) abnormalities associated to pachychoroid features, with no history or findings indicative of subretinal fluid or soft drusen were evaluated. All eyes underwent comprehensive ophthalmic examination, fundus photography, SS‐OCT and OCT‐A. After binarization of B‐scan images with ImageJ Software, the choroidal vascularity index (CVI), the choroidal vascularity proportion (CVP) and flow voids area were calculated. Results: A total of 27 eyes of 23 patients, 19 of whom were male (70.37%), with a mean age of 59.11 ± 12.76 years were enrolled in this study. We detected six different types of RPE lesions: focal disruption in ellipsoid and interdigitation zones in 18 eyes (66.66%), RPE elevation with microbreak appearance in 12 eyes (44.44%), RPE thickening in 10 eyes (37.03%), small pigment epithelium detachment in seven eyes (25.92%), RPE spike in five eyes (18.51%) and outer nuclear layer thinning in five eyes (18.51%). The subfoveal choroidal thickness (SFCT) was 399, 78 ± 88, 13 μm. The mean inner choroidal thickness was 87.18 ± 36.67 μm. The CVI was 65.28 ± 3.35%. The CVP was 59.10 ± 0.58% in the choriocapillaris and 59.69 ± 1.42% in the Haller layer. The total choriocapillaris flow void area was 39.87 ± 1.21%. Conclusions: SS‐OCT and OCT‐A are valuable diagnostic tools to characterize pigment epithelium and choroidal changes in PPE eyes.