Stereoacuity in Patients with Non-Amblyopic Anisometropia

Abstract

Purpose: To compare the stereoacuity between patients with uncorrected and corrected non-amblyopic anisometropia, and to evaluate the correlation between the degrees of anisometropia and stereoacuity.Methods: We retrospectively reviewed the records of patients with non-amblyopic anisometropia who underwent the stereoacuity test. Patients were divided into uncorrected anisometropia (n = 33) and corrected by spectacles (n = 30) groups. The clinical characteristics and sensory status of patients were evaluated using the Worth 4-dot, Titmus, Lang II, and TNO tests, and compared between the groups. Correlation analysis was performed between the degree of anisometropia and the level of stereopsis.Results: The uncorrected and corrected anisometropia groups did not significantly differ in mean age (12.2 ± 3.7 and 11.8 ± 4.0 years) or degree of anisometropia (2.12 ± 1.21 and 1.81 ± 1.25 diopters). The rate of sensory fusion in the distant Worth 4-dot test was lower in the uncorrected anisometropia than the corrected anisometropia group. The level of stereopsis was also worse in the uncorrected anisometropia than the corrected anisometropia group in all stereoacuity tests. There was a strong positive correlation between the degree of anisometropia and the level of stereoacuity on the Titmus, Lang II, and TNO tests (r = 0.690, r = 0.614, and r = 0.655, respectively; all p < 0.001) in the uncorrected anisometropia group. However, the corrected anisometropia group showed a weak positive correlation between the degree of anisometropia and the level of stereoacuity only on the TNO test (r = 0.366; p = 0.047).Conclusions: Stereoacuity was better in the corrected anisometropia group than in the uncorrected group. It significantly worsened with increasing anisometropia in the uncorrected group, but only a weak correlation was observed in the corrected group. Therefore, prescribing glasses could be recommended to improve stereopsis in adolescents and young adults with anisometropia.