Lens power and associated factors affect ocular response to highly aspherical lenslets (HAL) in myopic children

To characterize associations between ocular biometrics and lens power (LP), identify nonlinear inflection points, and evaluate their role in modulating the myopia control efficacy of highly aspherical lenslets (HAL).

This retrospective study included two cohorts. The cross-sectional cohort (n = 559, mild-to-moderate myopia) was analyzed using Pearson/Spearman correlation and Generalized Additive Mixed Models (GAMMs) to explore associations and nonlinear relationships.The 12-month HAL follow-up cohort (n = 62 children) was evaluated using repeated-measures ANOVA and ANCOVA. Subgroup analyses stratified by myopia progression speed (based on annual spherical equivalent (SE) change and axial length (AL) growth) were performed using chi-square and Mann-Whitney U tests.

GAMMs identified critical inflection points: AL = 24.0 mm, AL/CR = 3.15, and lens thickness (LT) = 3.3 mm. LP decreased more rapidly in subgroups with AL ≤ 24 mm, AL/CR < 3.15, or LT > 3.3 mm(P < 0.05). HAL wearers with AL ≤ 24 mm, AL/CR < 3.15, or LT > 3.3 mm showed faster LP reduction. The slow-progression group exhibited significantly greater annual LP reduction than the rapid-progression group (-0.28 ± 0.44 D vs. -0.03 ± 0.42 D, P = 0.02). Stage-specific analysis showed HAL's strongest regulatory effect on SE and LP occurred during the 3-6 month interval.

We identified nonlinear relationships and critical inflection points between ocular biometrics (AL = 24.0 mm, AL/CR = 3.15, LT = 3.3 mm) and LP. Gender was significantly associated with LP, and AL/CR was superior to AL alone for evaluating lens compensation. AL > 24 mm and AL/CR ≥ 3.15 indicate exhausted lens compensation and rapid myopia progression. HAL provides effective myopia control, and these inflection-based thresholds enable clinical risk stratification and personalized intervention with improved precision and efficacy.