Motor Success and Reoperation After Surgery for Adult Intermittent Exotropia: A Systematic Review and Meta-analysis

© 2026 by the Authors. Licensee Whioce Publishing, Singapore. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )

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Abstract

Objective: To estimate pooled motor success and reoperation rates in adult intermittent exotropia (IXT), evaluating the impact of surgical technique, follow-up, and success definitions. Methods: We searched PubMed, Embase, and Scopus (inception–March 2026) for adult (≥ 18 years) intermittent exotropia surgery outcomes. Proportions were Freeman-Tukey transformed and pooled via a random-effects model. We assessed MINORS quality and performed subgroup/sensitivity analyses. Results: This study included 14 studies (18 arms, 793 patients). Pooled motor success was 78.3% (95% CI 72.4–83.8%; I² = 65.0%). Success definition was the sole significant modifier: 83.1% for ≤ 10 prism diopters (PD) exodeviation vs. 67.6% for ≤ 10/5 PD (P = 0.029). Reoperation rates (5 studies) ranged from 0–25%. Conclusion: Adult IXT surgery yields about 78% motor success, with variability primarily driven by inconsistent outcome definitions. Standardizing strict criteria and extending follow-up are essential to accurately characterize long-term outcomes.

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