Augmented inferior rectus transposition with medial rectus recession in treatment of chronic unilateral sixth nerve palsy

Background to report the results of augmented inferior rectus muscle transposition (IRT) in management of chronic sixth nerve palsy. Methods a retrospective review of medical records of patients with chronic complete sixth nerve palsy who were treated by augmented full thickness IRT to the lateral border of the paralyzed lateral rectus muscle. Patients were selected for IRT if there was more limitation of abduction in inferior gaze associated with V- pattern esotropia. Medial rectus recession (MRRc) was performed in case of positive intraoperative forced duction. Effect on primary position esotropia, face turn, amount of V-pattern and limitation of ocular ductions were reported and analyzed. Results the review revealed 11 patients (7 males) with chronic unilateral sixth nerve palsy who were treated by simultaneous augmented IRT and MRRc. Causes of sixth nerve palsy were trauma (6 cases), vascular (3 cases), inflammation and congenital (one case each). Mean age of the patients at the time of surgery was 35.6 years (range; 11-63) and mean follow up was 8.6 months (range; 6-13). Postoperatively, average correction of esotropia, V-pattern, face turn and limited abduction were 35.9 PD, 11.4 PD, 25.9 degrees and 2.2 unit, respectively (p < .00). Postoperative complications in the form anterior segment ischemia, symptomatic induced vertical deviations were not found. Conclusions In cases of chronic unilateral sixth nerve palsy associated with more limitation of abduction in downgaze and V-pattern esotropia, augmented IRT could be considered as an effective and safe modality.