Association of Retinal Microvasculature With Myopia Progression in Children: The Hong Kong Children Eye Study.

Purpose: To investigate the associations between optical coherence tomography angiography (OCT-A) metrics and myopia progression in children.

Methods: This prospective, longitudinal cohort study recruited children ages 6 to 8 years for 2- to 6-year follow-ups. OCT-A captured macular images from the superficial capillary plexus (SCP) and deep capillary plexus (DCP). Annual progression of spherical equivalent (SE) and axial length (AL) was calculated as (SE/AL at last visit - SE/AL at baseline)/follow-up duration. Multivariable linear regression analysis evaluated the associations of OCT-A metrics with SE/AL progression. Restricted cubic spline (RCS) analysis evaluated both linear and nonlinear associations. Holm-Bonferroni correction was applied to account for multiple comparisons.

Results: A total of 920 children were analyzed. Multivariable linear regression, adjusted for age, sex, baseline SE/AL, and other covariates, showed that baseline foveal avascular zone (FAZ) circularity was negatively associated with annual AL elongation (β = -0.06; 95% confidence interval [CI], -0.10 to -0.02; adjusted P = 0.045). Similarly, the baseline FAZ circularity was positively associated with annual SE progression (β = 0.15; 95% CI, 0.05-0.26; adjusted P = 0.045). No significant associations were found between OCT-A metrics in the DCP with annual AL/SE progression. Furthermore, RCS analysis demonstrated no significant nonlinear associations between OCT-A metrics and annual AL/SE progression (P for nonlinearity > 0.05).

Conclusions: Baseline FAZ circularity in the SCP was significantly associated with annual AL elongation and annual SE progression in children, suggesting its potential as an imaging biomarker for monitoring myopia progression.