To assess the postoperative surgical outcomes and the changes in deviation in patients treated by supermaximal recession and resection of rectus muscles to correct the large-angle exotropia with a mean follow-up of one years.

: In this prospective interventional case series, patients with primary constant exotropia with angles ≥60 D underwent strabismus surgery on two horizontal muscles. Surgery consisted of bilateral lateral rectus muscles recession up to 12.5 mm in patients with bilateral deviation and up to 12.5 mm of lateral rectus recession combined with up to 8 mm medial rectus resection for unilateral exotropia on the nonfixing eye . Success was defined as horizontal deviation of ≤15 D.

A total of 83 patients were included. The mean age at surgery was 23.19±11.29 years. The mean preoperative exodeviations for bilateral and unilateral deviations were 67.3±7.6 and 74.2±12.1 respectively. At final follow-up examination, the mean postoperative (residual) deviations was 9.40±9.5 D. At the last follow-up 79.5% were successfully aligned. 9.6% of patients had persistent moderate limitation in the field of recessed or opposite field of resected muscles. no patient had diplopia on lateral gazes.

: In this patient cohort, supermaximal surgery on two muscles for large-angle exotropia successfully restored alignment in primary gaze in near 80% of cases without inducing symptomatic abduction deficits.