Inferior Rectus Transposition: A Novel Procedure for Abducens Palsy

Abstract

Superior rectus transposition has been popularized for the treatment of abduction deficiencies. Potential complications include induced vertical deviation and torsion. A new procedure, the inferior rectus transposition (IRT), may be similarly beneficial for patients at risk for postoperative vertical deviation or incyclotropia. The purpose of this study is to describe the outcomes of patients undergoing IRT. Prospective, interventional case series. Five patients in an academic pediatric ophthalmology and strabismus practice with a complete lateral rectus palsy who underwent IRT were studied. Changes in anomalous head posture, ocular rotations, ocular alignment, and torsion preoperatively to postoperatively were compared. The patients ranged in age from 19-89 years. There was a significant correction in the angle of esotropia (ET) from 39±17Δ (14-55Δ) to 12 ± 9.8Δ (0-22Δ) postoperatively (P= .02). Two of 5 patients had preoperative hypertropia of the affected eye (1.4 ± 2.2Δ; range, 2-5Δ). One of those had no vertical deviation postoperatively and 1 patient resulted in 2Δ hypotropia. One patient without vertical misalignment preoperatively developed a small postoperative vertical deviation. Torticollis significantly improved from 31.4 ± 11.6° to 5 ± 5.8° (P= .004). All patients improved abduction, with a mean of-4.4 ± 0.5 preoperatively to-3.4 ± 0.9 postoperatively (P= .07). Initial postoperative follow-up in patients with abducens palsy undergoing IRT shows a significant improvement in ocular alignment and torticollis. In patients with preoperative hypertropia, IRT resulted in a downward shifting effect on the operated eye. IRT may be a beneficial procedure for patients with preoperative hypertropia or intorsion requiring transposition procedures. Future studies with larger populations and longer durations of follow-up will be required before this procedure can be recommended.