Three Horizontal Muscle Surgery for Large-Angle Infantile or Presumed Infantile Esotropia: Long-term Motor Outcomes

IMPORTANCE Bilateral medial rectus muscle recession and one lateral rectus muscle resection surgery for the correction of large-angle infantile esotropia may be associated with a favorable long-term motor outcome. A consecutive exotropic drift was encountered more commonly than a recurrent esotropic drift in the long run, especially in the smaller (50-69 prism diopters [Δ]) range of preoperative esodeviation. OBJECTIVE To outline the short- and long-term motor outcomes of graded bilateral medial rectus muscle recession and one lateral rectus muscle resection for the correction of large-angle esotropia (≥50Δ). DESIGN Retrospective analysis. SETTING Strabismus service, tertiary care university referral center. PARTICIPANTS A total of 194 consecutive patients with infantile or presumed infantile esotropia. EXPOSURE All patients underwent bilateral medial rectus recession and a lateral rectus resection in the nondominant eye by the same surgeon. MAIN OUTCOMES AND MEASURES Short-term (8 weeks) and long-term rates of postoperative successful alignment (±10Δ), undercorrection, and overcorrection. RESULTS The median age of patients at surgery was 2.7 years (range, 20 months–36 years). The median follow-up time was 4.5 years (range, 6 weeks–25 years). The mean preoperative deviation was 68.2Δ. Of the 194 patients, 121 (62.4%) were successfully aligned at the last follow-up visit or prior to reoperation, and 154 (79.4%) were successfully aligned at the 8-week postoperative evaluation. A comparison of early vs late outcomes revealed a higher rate of late overcorrections (5.15% vs 24.1%, respectively; P = .001) but the same rate of undercorrections (15.4% vs 15.1%; P = .85). The outcome of surgery was not associated with the presence of amblyopia, high hyperopia, or the total amount of millimeters of surgery but was adversely influenced by the presence of inferior oblique overaction and the magnitude of the preoperative esodeviation. Delayed consecutive exotropia was more prevalent in the 50Δ to 69Δ range of preoperative esodeviation. CONCLUSIONS AND RELEVANCE Three horizontal muscle surgery for the correction of large-angle esotropia is associated with a high success rate. Long-term follow-up indicated that an exotropic drift may be expected 3 times more often than an esotropic drift.