Abstract
Purpose :
Treatment of diplopia in adults with convergence insufficiency (CI) exotropia is challenging as surgery frequently results in distance and lateral gaze esotropia. Recent evidence demonstrates differential compartmental function of extraocular muscle fiber groups. The purpose of this study is to evaluate the efficacy of a treatment algorithm for convergence insufficiency (CI) exotropia using surgery on selective muscle fiber groups.
Methods :
Seven adults with a near distance disparity (NDD) >= 8Δ were included in this retrospective study. Patients with a NDD<15Δ and a distance deviation of <10Δ were treated with lateral rectus (LR) inferior marginal tenotomy, those with NDD>15Δ and distance deviation of >10Δ were treated with LR slanted recessions, and those with limitation in adduction with negative forced duction testing were treated with medial rectus (MR) inferior fiber plication. Success was defined <8Δ of exotropia (XT) at distance and near without overcorrection, and a NDD<=8Δ.
Results :
Postoperatively the mean distance deviation was reduced from 8.29±7.60Δ to an overcorrection of 5.85±17.32Δ, and the near deviation from 21.00±10.55Δ to an overcorrection of 2.57±12.31Δ. The NDD was reduced from 12.71±3.35 to 3.29±5.62Δ. Six of the 7 (85.71%) patients met criteria for success. One subject was overcorrected at near and distance at post-operative month one requiring reoperation.
Conclusions :
CI exotropia remains a surgical challenge. Treatment may be optimized when using an individualized approach favoring selective lateral rectus and medial rectus procedures when possible. Preliminary data reveal that selective techniques eliminate diplopia while collapsing NDD in patients with CI exotropia. A focused algorithm will help surgeons select the procedure most likely to benefit each individual patient.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.