Longitudinal development of ocular biometric components and refractive error in children with hyperopic anisometropia

To compare the longitudinal development of spherical equivalent refraction (SER) and ocular biometric components in the more hyperopic (MoreH) and less hyperopic (LessH) eyes of children with hyperopic anisometropia.

This prospective longitudinal study included 36 children aged 4 to <13 years with hyperopic anisometropia without strabismus. Based on a best-corrected interocular visual acuity difference ≥0.20 logMAR, participants were classified as amblyopic (N = 31) or non-amblyopic (N = 5). SER was derived from cycloplegic refraction and anisometropia was defined as an interocular SER difference ≥1 D. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and keratometry (K1, K2) were obtained. Corneal curvature (CR) was calculated and the AL/CR ratio determined. Mean follow-up was 3.7 ± 1.4 years, with 5.8 ± 2.4 visits per child. A linear mixed-effects model estimated the rate of change for SER and the ocular components, comparing the MoreH and LessH eyes.

Baseline anisometropia was 2.66 ± 1.22 D. There were significant differences between the MoreH and LessH eyes for baseline AL, ACD and AL/CR (all p < 0.05). SER change with age was slower for the MoreH than the LessH eyes (-0.11 vs. -0.31 D/year, p < 0.001). The rates of change for AL (0.11 vs. 0.19 mm/year, p < 0.05) and AL/CR (0.01 vs. 0.02, p < 0.001) also were slower for the MoreH eyes. Anisometropia increased with age in the amblyopic subgroup (0.08 D/year) and decreased in the non-amblyopic subgroup (-0.17/D/year; p < 0.001).

In children with hyperopic anisometropia, axial elongation was slower in the MoreH than in the LessH eyes, particularly in those with amblyopia.