Six-month binocular stereopsis recovery and its influencing factors in children with intermittent exotropia

Abstract

Objective To investigate the recovery of binocular stereopsis recovery and its influencing factors in children with intermittent exotropia after successful correction of eye position. Methods Prospective clinical study. A total of 178 patients, aged 9 ∼ 14 (10.8 ± 1.7) years, who were successfully corrected after intermittent exotropia surgery at the Beijing Tongren Hospital Affiliated to Capital Medical University from October 2023 to September 2023 were collected, the follow-up duration was six-month or longer. Paired t test, Pearson correlation analysis and multivariable linear regression analysis were used to probe preoperative clinical features that may predict the stereopsis six months after surgery. Results Six months after surgery, the angle of deviation of the patients met the orthotopic standard, and there was significant difference compared with that before surgery (distant: -2.7△±3.2△ vs. -30.5△±8.4△, t=-25.3, P < 0.001. Near:-3.7△±4.1△ vs. -33.7△±8.0△, t=-26.1, P < 0.001). Distant stereopsis (3.0 ± 0.6 vs. 3.9 ± 0.4, t = 4.9, P < 0.05) and near stereopsis (2.3 ± 0.5 vs. 2.6 ± 0.4, t = 3.8, P < 0.05) were both significantly improved compared with that of before surgery. 17% and 22% patients rebuilt normal distant stereopsis and normal near stereopsis, respectively. Preoperative distant stereopsis (r=-0.26, P = 0.004) and near stereopsis (r=-0.23, P = 0.011) was significantly negatively correlated with convergence reserve. Multivariable analysis showed that patients’ age (β = 0.003, p = 0.037), anisometropia (β = 0.015, p = 0.043), and preoperative distant stereopsis (β = 0.456, p < 0.001) were significantly associated with postoperative distant stereopsis. Patients’ age (β = 0.005, p = 0.044), anisometropia (β = 0.127, p = 0.034), angle of deviation (β=-0.230, p = 0.020), and preoperative near stereopsis (β = 0.136, p < 0.001) were significantly associated with postoperative near stereopsis. Conclusion IXT patients could get eye position fixed after surgery, about 20% patients benefited from stereopsis improvement. Patient’s age, binocular anisometropia, angle of deviation and preoperative stereopsis were independent factors influencing postoperative stereopsis.