Association between ocular sensory dominance and refractive error asymmetry in myopes

Abstract

Objective To investigate the association between ocular sensory dominance and interocular refractive error difference (IRED) based on the discrimination of Gabor signal in myopes. Methods From December 2014 to October 2015, 361 myopia subjects at Eye Hospital of Wenzhou Medical University were recruited. Among them, based on the asymmetry between interocular spherical equivalent (SE), 177 subjects were non-anisometropic (IRED≤1D), 184 subjects were anisometropic (IRED>1D).Ocular sensory dominance was measured with computer-based psychophysics techniques. Ocular Sensory Index (OSI) was recorded when a subject just detected the Gabor signal during each trial. T-test was used to compare the 50 OSI values collected from each eye, and the t-val-ue was used as a subject’s ocular dominance index (ODI). Results No significant differences were found in SE, J0 and J45 between non-anisometropic and anisometropic subjects. IRED in non-anisometropic and anisometropic subjects were-0.58±0.33D and-2.52±1.29D respectively, which had significant differences between them (Wilcoxon rank sum test, Z=-20.13, P <0.01). ODI in anisometropic subjects was 4.04±3.74, which was significantly higher than ODI (3.35±2.87) in non-anisometropic subjects (Wilcoxon rank sum test, Z=-2.08, P=0.04). In anisometropic subjects, the IRED was correlated with ODI (Pearson correlation analysis, R=0.39, P <0.01). What’s more, the dominant eyes were more myopic in these anisometropic subjects (sign-test, P <0.05). Conclusions The anisometropic myopes have stronger ocular dominance in comparison to non-anisometropic myopes. ODI in myopes with clear dominance is associated with IRED, and the dominant eyes are more myopic. Key words: Sensory dominance; Anisometropia; Psychophysics; Myopia