A Prospective Study of Anterior Segment Ocular Parameters in Anisometropia

Abstract

Purpose: The aim of this study was to investigate the differences in anterior segment ocular parameters in anisometropia >1 D. Methods: This study included 202 eyes of 101 subjects ranging from 10 to 40 years of age with anisometro-pia of 1 D or more. The subjects were divided into groups according to anisomyopia, anisoastigmatism, and anisohypermetropia. After providing informed consent, each patient underwent a detailed ophthalmological examination including cycloplegic refraction, best-corrected visual acuity, cover test, axial length (AL) mea-surement using A-scan ultrasound biometer, keratometry, anterior chamber depth, and central corneal thick-ness measurement. For each participant, the eye with greater refractive error was compared to the fellow eye via paired t-tests. Correlations between parameters were studied using the Pearson correlation coefficient. Results: The average age of subjects was 21.7 ± 9.3 years. Of 101 subjects, 31 had anisomyopia; 42 had aniso-hypermetropia; and 28 had anisoastigmatism. A predisposition toward greater myopia in right eyes was noted in anisomyopia (24 of 31 subjects, 77%). The inter-ocular acuity difference was significant in all three groups (p < 0.01). As the degree of anisometropia increased, there was significant positive correlation in the difference in AL in myopes (r = 0.863, p < 0.01) and hypermetropes (r = 0.669, p < 0.01) and the difference in corneal curvature in anisoastigmatism (r = 0.564, p = 0.002) and hypermetropes (r = 0.376, p = 0.014). A significant positive cor-relation was also present between the anterior chamber depth difference and refractive difference in hyper-metropes (r = 0.359, p = 0.020). Conclusions: This study showed that anisomyopia is correlated only with anterior chamber differences.