To describe the effect of graded unilateral vs bilateral lateral rectus resection in the treatment of residual or recurrent esotropia after maximal medial rectus muscle recession.
Retrospective case series of children with residual or recurrent esotropia. All children underwent initial eye muscle surgery for angles of 40 to 60 prism diopters (medial rectus recession of 5.5-6.5 mm; 11.0-11.5 mm from surgical limbus). If significant esotropia persisted or recurred, surgical results from graded lateral rectus resection were recorded.
Thirty-eight children were identified for the study. Unilateral lateral rectus resection ranging from 4 to 7 mm resulted in mean esotropic corrections of 10.5 to 14.9 prism diopters. Differences in surgical response per millimeter of unilateral lateral rectus resection were not significant. Bilateral lateral rectus resection of 5, 6, and 7 mm resulted in a mean correction of 19.75, 28.75, and 33.5 prism diopters, respectively.
Graded lateral rectus resection can produce highly variable results on a case-to-case basis, but mean values trend in the expected direction. Residual deviations larger than 15 prism diopters need to be addressed with bilateral surgery.