Three-dimensional stochastic retinal models for synthetic eye-models
Purpose: Current eye models often assume a fixed spherical retinal curvature of 12 mm, which does not reflect the anatomical variability observed in vivo. This study proposes an extension incorporating the stochastic relationship between axial length and three-dimensional (3D) retinal curvature, enabling more realistic 3D eye models. Methods: Axial length and 3D retinal curvature data from 94 subjects, split into five subsets for cross-validation, were used to construct two probabilistic models: a Single Gaussian Model (SGM) and two-component Multi Gaussian Mixture Model (MGMM). Both were converted into conditional forms to estimate retinal curvature for a specific axial length, and evaluated against measured data distributions. Results: All models produced radii of curvature comparable to measured data (median difference <0.2 mm). Non-conditionally, the MGMM described the distribution slightly better than SGM, with higher density overlap (>94% vs. >86%), but similar variance (worst f-test (p-value) 1.05 (0.71) vs. 1.05 (0.73)). Conditioned on axial length, both models performed similarly with overlap exceeding 93% and the worst f-test 1.02 (0.84). Given its simplicity and robustness, the conditional SGM was selected, achieving similar validation results: median difference (<0.10 mm), overlap (>92%), and a non-significant worst f-test (1.02 (0.85)). Conclusions: The conditional SGM enables accurate generation of anatomically realistic 3D retinal curvatures based on axial length, supporting improved stochastic eye modeling for visual optics and population-based simulations of healthy eyes. Translational relevance: Replacing the fixed 12 mm retina assumption with a population-based stochastic model improves anatomical accuracy of eye models used in optical design and treatment planning.