Fig. 1. Retinal curvature measurements. (A) Conventional OCT image. (B) Corrected OCT image reflecting the true retinal morphology after using AL’s optical correction algorithm. (C) 3D retinal model. (D) Retinal curvature results model of the right eye from a 24-year-old normal woman for comparison, with the axial length of 23.52 millimeters. Positive values of RC indicate retinal depression and negative values indicate convexity; larger absolute values of RC indicate more curvature and a steeper retina, and vice versa. (E) Retinal curvature results model of the right eye from a 30-year-old highly myopic woman with the axial length of 27.01 millimeters. (F) RC I to RC VI are the mean values of a series of concentric circles with diameters of 1, 3, 6, 9, 12, and 15 mm centered on the fovea centralis.

Methods: In this cross-sectional study of 147 adults (51 HM, 96 controls), ultra-widefield swept10 source optical coherence tomography (SS-OCT) with Gaussian curvature mapping quantified RC  across six concentric zones (diameters 1-15 mm). Ocular parameters, including Corneal K, lens  thickness (LT) and axial length (AL) were measured using Lenstar LS 900, and retinal thickness (RT),  choroidal thickness (ChT), choroidal vascularity index (CVI), and RC were measured by ultra-wide field SS-OCT. Correlation and regression analyses identified factors influencing RC.

Results: HM participants had longer AL, thinner ChT, higher CVI, and flatter macular RC versus NHM 16 group (p<0.05). Multiple linear regression analysis demonstrated that peripheral retinal regions  beyond 6 mm exhibited significant negative correlations with AL (r = -0.296 to -0.478), while central  regions within 9 mm showed positive associations with CVI (r = 0.180-0.214). RT was negatively  correlated with RC in perimacular regions (r = -0.19), but no significant association was observed between equivalent spherical refractive power (SER) and RC in any measurement region.

Conclusions: Retinal curvature alterations in high myopia demonstrate spatial heterogeneity, featuring peripheral biomechanical adaptation to ocular elongation and central structural changes modulated by choroidal vascular integrity. Integrating RC into clinical assessments could enhance monitoring of biomechanical changes in HM. Longitudinal studies are needed to validate its  predictive role in myopia progression.