IMPACTS OF POSTERIOR STAPHYLOMA ON PARAPAPILLARY MICROVASCULATURE AND ATROPHY IN HIGH MYOPIC EYES: A MATCHED COHORT STUDY WITH OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

Purpose: We aimed 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.

Methods: 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. PS types, parapapillary microvasculature characteristics, the prevalence of non-juxtapapillary microvasculature dropout (NJ-MvD), the longest radial width from the optic disc edge to retinal pigment epithelium atrophy edge (PPA-w), γ-zone, and δ-zone with changes in visual field and best-corrected visual acuity (BCVA) were evaluated and analyzed.

Results: According to Curtin's 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 disc tilted ratio and larger PPA-w compared to 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 BCVA, and a higher incidence of NJ-MvD compared to primary PS. Choroidal and intrascleral vessels were associated with NJ-MvD and were located near or connected to the circle of Zinn-Haller.

Conclusions: Eyes with high myopia and PS show wider PPA, affecting the γ-zone and δ-zone, and are at a higher risk of developing NJ-MvD. Specifically, eyes with PS types VII and IX are more susceptible to visual field damage and decreased BCVA. These results highlight the importance of impact of PS on PPM and PPA in high myopia.