The association between ocular dominance and physiological palpebral fissure asymmetry

Physiological palpebral fissure asymmetry is a common observation in a physician's everyday practice. The goal of this study was to examine the relationship between palpebral fissure height (PFH) and ocular dominance. Sixty-nine healthy volunteers (42 female, 27 male) were included in this research, and ocular dominance was determined using hole-in-the-card and pointing-a-finger tests. Those volunteers with inconsistent test results were excluded. Standard photographs were taken of all of the subjects in the primary position with a consistent background and photographic equipment. The PFHs were measured using an ImageJ analyser, and a mixed ANOVA was used for the statistical analysis. Overall, 87% of the participants showed small differences in their PFHs, with their dominant eyes being significantly wider than their non-dominant eyes (10.51 ± 0.97 vs. 10.32 ± 1.03; p = .001). This study revealed that ocular dominance has a significant effect on the PFH. Further research is required to understand the importance of this association in daily practice.