IMPACTS OF POSTERIOR STAPHYLOMA ON PARAPAPILLARY MICROVASCULATURE AND ATROPHY IN HIGH MYOPIC EYES: A Matched Cohort Study With Optical Coherence Tomography Angiography.

Abstract

To evaluate the impacts of the different types of posterior staphyloma (PS) in high myopia on parapapillary microvasculature and parapapillary atrophy (PPA, i.e., γ-zone and δ-zone) with optical coherence tomography angiography. This cross-sectional study included 152 high myopic eyes (152 participants) with γ-zone. After matching, high myopic eyes were stratified into PS (n = 33) and non-PS (n = 33) groups. Posterior staphyloma types, parapapillary microvasculature characteristics, the prevalence of nonjuxtapapillary microvasculature dropout, the longest radial width from the optic disk edge to retinal pigment epithelial atrophy edge (PPA width), γ-zone, and δ-zone with changes in visual field, and best-corrected visual acuity were evaluated and analyzed. According to Curtin classification, we identified five types of PS included: primary Types I, II, III, and compound Types VII, and IX. Eyes with Type II showed a higher optic disk tilted ratio and larger PPA width compared with other primary PS. Subjects with Type IX were the oldest. Eyes with Types VII and IX had wider γ-zone and δ-zone, worse visual field outcomes, poorer best-corrected visual acuity, and a higher incidence of non-juxtapapillary microvasculature dropout compared with primary PS. Choroidal and intrascleral vessels were associated with nonjuxtapapillary microvasculature dropout and were located near or connected to the circle of Zinn-Haller. Eyes with high myopia and PS show wider PPA, affecting the γ-zone and δ-zone, and are at a higher risk of developing nonjuxtapapillary microvasculature dropout. Specifically, eyes with PS Types VII and IX are more susceptible to visual field damage and decreased best-corrected visual acuity. These results highlight the importance of the impact of PS on parapapillary microvasculature and PPA in high myopia.