In Vivo Evaluation of Peripapillary Scleral Architecture in Myopia and Glaucoma Using Polarization-Sensitive Optical Coherence Tomography

Purpose: To quantitatively characterize the in vivo peripapillary sclera (PPS) architecture using polarization-sensitive optical coherence tomography (PS-OCT) and evaluate its association with axial length (AL) and glaucoma. Methods: A total of 94 eyes from 94 participants (AL, 23.52-31.31 mm), including 64 normal-tension glaucoma (NTG) eyes and 30 nonglaucomatous eyes, were enrolled in this retrospective study. PS-OCT optic axis maps identified a two-layered structure consisting of an outer circumferential ring (CR) encircling the optic nerve head (ONH) and an inner radial layer (IRL). CR width was measured at the temporal side of the ONH. The IRL and peripapillary choroidal thickness were measured at seven temporal-half sectors. Associations with AL and sectoral variations in these associations were analyzed using multiple linear regression and linear mixed-effects models. A subanalysis compared the PPS structure of age-, sex-, and AL-matched NTG and nonglaucomatous eyes. Results: CR width was positively associated with AL (P = 0.006). IRL thickness was thinnest in inferior sectors and negatively associated with the AL (P < 0.017), with no significant slope differences across temporal-half sectors (AL × sector interaction P = 0.578). The association between peripapillary choroidal thickness and AL showed significant sectoral heterogeneity (AL × sector interaction P < 0.006), with more negative slopes in temporal sectors (P < 0.006). No significant differences in PPS parameters were observed between NTG and nonglaucomatous eyes (all P > 0.05). Conclusions: PS-OCT enabled the in vivo quantitative assessment of the PPS architecture, revealing layer-specific structural associations with AL (with sectoral differences) and comparable PPS features between NTG and nonglaucomatous eyes. These layer-specific scleral characteristics may provide a biomechanical framework for understanding myopia-related ONH deformation.