Corneal aberrations andanisometropia in children

Abstract

Clinical relevance: Children with anisometropia have different refractive errors in each eye. Studies reported similar ocular higher-order aberrations (HOAs) in each eye within anisometropia. It is unclear whether binocular corneal HOAs within anisometropia are likewise similar. This study compared interocular differences in corneal HOAs among children with anisometropia, and explored correlations between corneal HOAs and anisometropia.

Background: This study aimed to compare interocular differences in corneal aberrations in children with low and high anisometropia and to determine correlations between the size of interocular differences in corneal HOAs and the degree of anisometropia.

Methods: This was a retrospective, self-controlled study: 69 children with myopic anisometropia were divided into a high anisometropia group (34 children, interocular difference in spherical equivalent refraction ≧2D) and a low anisometropia group (35 children, 2D >interocular difference in spherical equivalent refraction ≧1D). Binocular corneal aberrations were measured using Sirius combined corneal topographer and tomographer. Paired t-tests, Wilcoxon rank sum tests, and Spearman correlation analyses were used in the current study.

Results: For the low anisometropia group, there were no statistically significant interocular differences in corneal HOAs (P>0.05). For the high anisometropia group, higher myopic eyes had lower coma in 3mm diameter than those of the contralateral eyes (in the total cornea and the anterior corneal surface; P<0.05). No interocular difference was found in corneal total higher-order aberration and spherical aberration in the high anisometropia group (P>0.05). Among all 69 children with anisometropia, interocular differences in coma were not correlated with the degree of anisometropia (P>0.05).

Conclusion: For children with high anisometropia, higher myopic eyes had lower coma than those of the contralateral eyes. However, no obvious correlation was found between interocular differences in coma and the degree of anisometropia.

Keywords: Anisometropia; corneal aberrations; corneal higher-order aberrations; interocular difference; optical qualities.