Asymmetry of posterior pole remodeling in high myopia.

To characterize posterior pole morphology in high myopia using widefield OCT angiography (OCTA)–derived curvature metrics, with particular emphasis on asymmetry and regional variation, and to determine whether posterior deformation shows structured spatial patterns beyond conventional axial length and refractive measures. Dual–center, cross–sectional observational study. Widefield (24 × 20 mm) OCTA scans were used to derive posterior pole curvature maps. Posterior curvature heterogeneity was quantified using the posterior heterogeneity index (PHI slope), and directional asymmetry was quantified using the nasal–temporal difference in curvature slope (NT diff slope). Linear mixed–effects models accounting for inter–eye correlation were used to compare high myopia (defined as axial length ≥ 26.0 mm or spherical equivalent refraction ≤ − 6.00 D) with non–high myopia, adjusting for age, sex, eye laterality, and study center. Continuous associations with axial length were evaluated, and robustness was assessed across centers and sensitivity analyses. Eyes with discordant axial–refractive phenotypes were analyzed separately. Compared with non–high myopia eyes, high myopia eyes demonstrated significantly greater posterior curvature heterogeneity (PHI slope) and more pronounced nasal–temporal asymmetry (more negative NT diff slope), suggesting a spatially asymmetric pattern of posterior pole curvature. These associations remained significant after adjustment and were consistent across both study centers. Increasing axial length was continuously associated with higher PHI slope and more pronounced nasal–temporal asymmetry. Notably, eyes meeting refractive but not axial criteria for high myopia exhibited posterior pole morphology more similar to concordant high myopia eyes than to non–high myopia eyes, consistent with a structural–refractive dissociation. Key curvature indices showed high short–term repeatability. Posterior pole deformation in high myopia was associated with greater curvature heterogeneity and more pronounced nasal–temporal asymmetry, rather than a uniformly distributed pattern. Widefield OCTA–derived curvature metrics may provide a reproducible and clinically interpretable framework that complements conventional axial length and refractive assessment, particularly in eyes with discordant structural and refractive characteristics. Widefield OCTA–derived curvature mapping provides quantitative, reproducible descriptors of posterior pole remodeling that complement conventional measures of myopia severity (axial length and refraction). These interpretable morphology indices may help describe and compare structural variation across eyes with different axial–refractive profiles, particularly in those with discordant axial–refractive characteristics.