Inferior Rectus Myopexy: Indications and Long-Term Results

Abstract

The rectus inferior myopexy is often used in vertical incomitant deviations without significant deviation in primary position. We analysed the long-term results in different pathologies. Retrospective study of patients operated on rectus inferior myopexy between 1984 and 2018. Vertical and torsional deviations were measured in primary position (PP) and 25° downgaze and the field of binocular single vision (FBSV) was evaluated with the Harms tangent screen, establishing a functional score. Postoperative follow-ups took place at 1month, 6 months and long term (1 - 24 years). 62 patients were included (mean age 41 years, 28women and 34 men). 47 presented a fourth nerve palsy (group 1) and 15 a reduced depression of other origins (group 2). 31 patients had undergone previous operations and 34contemporaneous operations with the myopexy. In group 1, preoperative mean vertical deviation was 6.4° in PP and 12.3° on downgaze, postoperative 4° and 7.2°. In group 2, the value decreased from 3.3° in PP and 11.5° on downgaze to 1.2° and 6.6°. Over the years, there has been a decrease in the effect, particularly in group 1. The torsion was hardly influenced in both groups. The median functional score of FBSV improved in group 1 from 10% preoperatively to 39% postoperatively and in group 2 from 25 to 69%. The inferior rectus myopexy shows an effective way to reduce the incomitance of vertical deviation without significant influence on torsion. Over the years, there has been a decrease in the effect, particularly in patients with superior oblique paresis. We do not consider inferior rectus myopexy as a classic surgical treatment of superior oblique paresis. We have only used it in special cases.