Lens power, cornea power and association with refractive error in children with moderate to high hyperopia

Objective: This study aimed to profile ocular biometry parameters and predictors of spherical equivalent refraction (SER) among children with moderate to high hyperopia.Methods: Individuals <18 years of age with moderate to high hyperopia were enrolled from November 2015 to November 2021. Participants underwent a series of comprehensive ocular examinations, and were classified as having low hyperopia, that is, SER +0.5 to < +2.0 D or moderate to high hyperopia, that is, SER >= +2.0 D.Results: A total of 459 and 230 eyes with moderate to high hyperopia and low hyperopia, respectively, were included. Moderate to high hyperopic eyes had a shorter axial length, stronger lens power (24.78 +/- 5.47 D vs. 18.74 +/- 1.63 D, p < 0.001) and weaker corneal power (42.82 +/- 1.75 D vs. 43.31 +/- 1.55 D, p < 0.001) than low hyperopic eyes. When comparing values before and after 5 years of age, both lens power and axial length differed significantly in the moderate to high hyperopia group, whereas in the low hyperopia group, they only differed significantly after 9 years of age. Lens power was negatively associated with AL in eyes with axial lengths between 20 and 22 mm. A multiple linear regression model which included axial length (standardised beta = -0.80, p < 0.001), corneal power (standardised beta = -0.47, p < 0.001) and lens power (standardised beta = 0.23, p < 0.001) explained 81.2% of the variance in SER.Conclusions: Differences in lens power and axial length in moderate to high hyperopic eyes became significantly smaller after 5 years of age, at least 4 years earlier than for the low hyperopia. Lens power could offset the axial elongation in participants with axial lengths between 20 and 22 mm, suggesting that children with moderate to high hyperopia might have different ocular growth patterns. Axial length, corneal power and lens power were the main predictors of SER in moderate to high hyperopia.