Interocular asymmetry and ocular biometric patterns in pediatric high myopia: implications for early risk...

To describe the clinical and ocular biometric characteristics of high myopia in children and adolescents, analyze the relationship between age and axial length (AL) and axial ratio (AL/CR), identify high-risk structural populations, and evaluate binocular asymmetry and follow-up progression.

We retrospectively extracted data from the outpatient medical record system of our hospital, including patients whose age at the last follow-up was less than 18 years and whose spherical equivalent (SE) of at least one eye was ≤ -6.00D. The last follow-up data were used as the main analysis, and best corrected visual acuity (BCVA), SE, axial length (AL), and AL/corneal radius (AL/CR) were extracted. Pearson correlation analysis was used to evaluate the correlation between age and AL, AL/CR. In addition, the differences between the left and right eyes of the same patient (| ΔSE|, | ΔAL|) were calculated, and a longitudinal description was made for the subset with repeated biometric records.

A total of 84 patients (47 males and 37 females) were included, with a total of 146 highly myopic eyes. The average spherical equivalent (SE) of highly myopic eyes was -8.87 ± 2.58D; the axial length (AL) was 26.41 ± 1.33 mm (n = 118); and the AL/corneal radius (CR) ratio was 3.38 ± 0.19 (n = 73). Age was significantly positively correlated with AL (r = 0.485, P < 0.001), and age was also significantly positively correlated with the AL/CR ratio (r = 0.505, P < 0.001). Generalized estimating equations (GEE) confirmed that age independently predicted AL (β = 0.200 mm/year, P < 0.001) and AL/CR (β = 0.028 per year, P < 0.001), and the effect of SE on AL remained significant after adjusting for age (β = -0.239 mm/D, P < 0.001). Anisometropia was relatively common in both eyes of the patients, with | ΔSE| ≥ 2.0D accounting for 27.7%. In the follow-up subset (34 eyes), the annual growth rate of AL was approximately 0.224 ± 0.264 mm/year.

Children with high myopia show obvious ocular structural abnormalities and heterogeneous progression. GEE analysis further validated the independent contributions of age and refractive error to axial elongation in this population. AL and AL/CR can be used as key structural indicators for follow-up; unilateral high myopia or significant binocular asymmetry suggests the need for enhanced individualized myopia monitoring and intervention.