Effect of Strabismus Surgery on Binocular Vision in Children: A Prospective Pre-Post Hospital-Based Study

Abstract

Background: Strabismus in childhood disrupts normal binocular vision development, leading to impaired stereopsis and sensory fusion. Although surgical correction restores ocular alignment, its effect on functional binocular outcomes remains variably reported, particularly in low- and middle-income settings. Objective: To evaluate changes in binocular vision following strabismus surgery in children and to assess demographic and clinical factors associated with postoperative functional outcomes. Methods: This prospective pre-post observational study included 135 children aged 3-16 years undergoing primary strabismus surgery at several tertiary care hospitals in Pakistan. Comprehensive ophthalmic assessments were performed preoperatively and at 12 months postoperatively. Binocular vision was evaluated using quantitative stereopsis testing and sensory fusion assessment. Motor alignment, amblyopia status, and surgical variables were also recorded. Paired t-test was used to compare preoperative and postoperative stereoacuity, while independent t-tests, chi-square tests, Pearson correlation, and binary logistic regression were used to evaluate associations and predictors of outcomes. Results: Mean stereoacuity improved significantly from 475.24 ± 245.82 arc seconds preoperatively to 309.82 ± 161.31 arc seconds at 12 months postoperatively, with a mean improvement of 165.41 arc seconds (p < 0.001). Fusion was achieved in 69.6% of patients, and motor success was observed in 65.2%. No demographic, clinical, or surgical factor independently predicted fusion recovery (all p > 0.05), although duration of symptoms showed a weak positive correlation with stereoacuity improvement (r = 0.178, p = 0.039). Conclusion: Strabismus surgery leads to significant improvement in stereopsis and satisfactory binocular vision recovery in children, although postoperative functional outcomes appear to be multifactorial and not explained by any single baseline predictor.