Comparison of bilateral medial rectus plication and resection for the treatment of convergence insufficiency-type intermittent exotropia

Purpose To compare the clinical outcomes of bilateral medial rectus plication and resection for the treatment of convergence insufficiency (CI)-type intermittent exotropia (IXT). Methods Fifty-five patients with CI-type IXT were included in this prospective study and were followed for 6 months. The patients were randomized into two groups: the bilateral medial rectus plication (BMRP) group (n = 27) and the bilateral medial rectus resection (BMRR) group (n = 28). The eye examinations of each patient were carried out before the surgery and at 1 day and 1, 3 and 6 months postoperatively. The success rate, angle of deviation, stereoacuity, operative time and postoperative conjunctival swelling and redness score were analysed. Results The mean deviation at distance at 1 day postoperatively was +6.6 +/- 5.6 prism dioptres (PD) in the BMRP group, which was lower than the value of +10.8 +/- 9.3 PD observed in the BMRR group (p = 0.046). There was more overcorrection in the BMRR group at first day after surgery. However, there were no significant differences in deviations or success rates were observed between the two groups at 1, 3 and 6 months after surgery (p > 0.05). The operative time in the BMRP (12.9 +/- 1.4 min) group was shorter than that in the BMRR (14.7 +/- 1.4 min) group (p < 0.001). Postoperative conjunctival swelling and redness were milder in the BMRP group than in the BMRR group (p < 0.001). Conclusion The BMRP surgery could be an alternative procedure to BMRR for the treatment of CI-type IXT with less immediate postoperative overcorrection and simpler, safer, less traumatic characteristics.