Efficacy of Transposition of Plicated Medial Rectus Muscles in the Treatment of Pattern Exotropia (A Comparative Study)

ObjectiveTo report effectiveness of bimedial plication and vertical transposition for correction of exotropia associated with A- or V-pattern and compare it with bimedial resection and vertical transposition. Methods and analysisWe retrospectively reviewed the results of surgery of patients who underwent bimedial plication (group I) versus bimedial resection (group II) with vertical offset to correct both exotropia and pattern deviation not secondary to oblique overaction in the period between January 2021 and January 2023. Results of both groups were compared. Success was considered when pattern deviation was [≤] 8 prism diopters PD and horizontal deviation was within 10 PD of orthophoria at 6 months postoperatively. ResultsThe mean preoperative angle of exotropia in PD was 40.6 {+/-} 7.2 in group I and 41.1 {+/-} 7.5 in group II (p=.8). At 6 months postoperatively, they achieved angle of 4.6 {+/-} 4.1 and 2.5 {+/-} 4.5 PD respectively (no significant difference between both groups; p=.19). The mean preoperative pattern deviation was 21.3 {+/-} 3.7 PD in group I and 21.6 {+/-} 4.4 in group II. Postoperative pattern collapse was 16.7 {+/-} 5.6 and 16.6 {+/-} 4.1 respectively. The percentage of success in pattern collapse was 90.6% in group I and 84.4% in group II (no significant difference between both groups; p=.71). ConclusionVertical transposition with plication of medial recti is a safe, effective, and rapid technique for correction of cases of A- or V- pattern exotropia not associated with oblique overaction. Results were not significantly different from resection/vertical transposition. What is already known in this topic?O_LIA- or V-pattern exotropia without significant inferior oblique overaction can be treated by vertical transposition of the horizontal recti after ordinary recession or resection. C_LIO_LISome studies reported muscle plication and transposition as an alternative technique to resection and transposition. Plication allow preservation of ciliary circulation and lowering the incidence of muscle loss. C_LI What this study adds?O_LIIn this retrospective study, we concluded that medial rectus plication and transposition is an effective alternative technique to medial rectus resection and transposition in treatment of A- or V- pattern exotropia without significant inferior oblique overaction (No significant difference between both techniques). C_LI What this study might affect research, practice or policy?O_LIVertical Transposition of plicated medial recti is a new promising technique which should be considered in managing cases of A- or V-pattern exotropia without significant inferior oblique overaction. C_LI