The effect of uncorrected ametropia on ocular torsion induced by changes in fixation

Abstract

Background and Objective Ocular torsion, the eye movements to rotating around the line of sight, has not been well investigated regarding the influence of refractive errors. The purpose of this study was to investigate the effect of uncorrected ametropia on ocular torsion induced by fixation distances. Methods Seventy-two subjects were classified according to the type of their refractive error, and ocular torsion of the uncorrected eye was compared based on changes induced by different fixation distances. Ocular torsion was measured using a slit-lamp biomicroscope equipped with an ophthalmic camera and a half-silvered mirror. Results In all groups, excyclotorsion values increased as the fixation distance decreased, but the myopia and astigmatism groups had larger amounts of ocular torsion than the emmetropia group. In addition, as the amount of uncorrected myopia and astigmatism increased, the amount of ocular torsion increased. Conclusion Since the amount of ocular torsion caused by a change to a shorter fixation distance was larger when the refractive error was uncorrected, we suggest that ametropia should be fully corrected in patients frequently exposed to ocular torsion due to changes in fixation distance.

The changes in ocular torsion after unilateral lateral rectus recession-medial rectus resection for intermittent exotropia

“…It is worth noting that DFA has been shown to have a positive association with age 27 , 28 . Additionally, there was an increase in extorsion observed in patients with uncorrected myopia and astigmatism 29 . However, some researchers have reported that DFA was not associated with age or refractive error in children 17 , 30 .…”