Unilateral rectus resection in the treatment of undercorrected or recurrent strabismus

Background: When surgery is required for an undercorrection or for a recurr ent strabismus that is in the same direction as the previous deviation, tra ditional options have included a rerecession of the previously operated mus cle(s), a marginal myotomy of the previously operated muscle(s) with or wit hout a resection of the direct antagonist, or a bilateral resection of the antagonist muscles. While many surgeons prefer to per-form a bilateral rese ction for these reasons, a unilateral resection would be a useful approach for small to moderate deviations. Methods: Data were collected for patients who had undergone a unilateral re ctus resection: age, number of prior surgeries, the preoperative deviation, the postoperative deviation at 1 week, 6 weeks, and 6 months, and the amou nt of surgery performed. An acceptable postoperative result was considered to be any deviation less than or equal to8 pd. Results: A resection of a single rectue muscle was undergone by 113 patient s. Complete data were available on 81 of these patients: 60 underwent a uni lateral resection of the lateral rectus and 21 underwent a unilateral resec tion of the medial rectus. Of those patients undergoing a unilateral latera l rectus resection, 90% were acceptably aligned at the 6-month postoperativ e exam. Among those patients undergoing a medial rectus resection, 95.2% ob tained a successful result. Conclusions: A unilateral resection of the medial or lateral rectus is an e ffective tool in the treatment of undercorrected or recurrent strabismus. I t is predictable, stable in the immediate postoperative period, and limits surgery to 1 eye.