Pencil push-up training compared with binocular vision training in the management of slight post-operative under-correction of intermittent exotropia: A prospective study

Purpose: This study aims to compare the effectiveness of pencil push-up training and binocular vision training in treating post-operative mild under-correction in patients with intermittent exotropia. Methods: A prospective cohort study was conducted, including patients who underwent surgery for intermittent exotropia at Children’s Hospital of Nanjing Medical University between June 2022 and January 2023 and experienced post-operative mild under-correction (-8∆ to -15∆). Patients were divided into two groups: pencil push-up training group and binocular vision training group. All patients underwent measurements of exodeviation and stereoacuity at distance and near, sensory fusion, and fusion convergence amplitude. The data were analyzed using independent sample t-tests, repeated measures analysis of variance, and Chi-square tests. Results: There were no statistically significant differences in exodeviation at distance and near between the two training groups before the training. After 6 months of training, the exodeviation at distance and near achieved a significant decrease in both groups (P < 0.05), and the pencil push-up training group showed a similar distance and near exodeviation compared to the binocular vision training group (t = 1.58, P ＞ 0.05; t = 0.43, P ＞ 0.05). After 6 months of training, the binocular vision training group exhibited significantly superior stereoacuity and fusion convergence amplitude compared to the pencil push-up training group (P < 0.001). Conclusion: Both pencil push-up training and binocular vision training are effective in reducing exodeviation in patients with post-operative mild under-correction of intermittent exotropia. However, binocular vision training demonstrates superior efficacy in restoring stereopsis and fusion convergence amplitude compared to pencil push-up training.