[Management of large exotropia with medial rectus muscle transection following endoscopic sinus surgery].

OBJECTIVE: To evaluate and compare the effect of surgeries in large exotropic patients who underwent a medial rectus muscle (MR) transection after endoscopic sinus surgery (ESS). METHODS: In 5 patients with exotropia (XT) and a lack of adduction after ESS, orbital CT revealed a complete transection of the midportion of the MR. 3 patients was treated within 3 months after injury. Foster procedure in 2 patients, augmented Hümmelsheim procedure in 1 other patients. Two patients were treated over 6 months after ESS with lateral rectus contraction. Surgery was divided into two stages. The adduction deficits were divided into -1 through to -8. The patients were followed up for more than than 6 months. RESULTS: Postoperatively, 5 patients showed orthophoria or small exophoria within -5°among which 4 had no diplopia in the primary position, another one avoid diplopia by prism lens. The adduction deficits improved to -2 to -5. CONCLUSIONS: Surgical management (vertical rectus muscle transposition) is effective in correcting a large exotropia secondary to a medial rectus transection after ESS. The best time for surgery is 3 months after injury.