Surgical effects of unilateral medial rectus plication for small-angle convergence insufficiency-type exotropia

To report the outcomes of patients who underwent unilateral medial rectus plication to treat small-angle convergence insufficiency-type exotropia, a condition characterized by greater exodeviation at near than at distance.

The medical records of patients operated on at a single institution between May 2020 and November 2023 were reviewed retrospectively. Angle data were collected at multiple pre- and postoperative time points. Distance and near angles were compared at three time points: preoperatively, 1-2 weeks postoperatively, and final visit.

Ten patients (2 males; mean age, 52.5 ± 22 years.) were included. Postoperative angles reduced significantly at both distance and near (preoperative, -7.8^Δ ± 4.2^Δ and -21.9^Δ ± 6.5^Δ; 1-2 weeks postoperatively, +4.0^Δ ± 6.0^Δ and -4.0^Δ ± 6.6^Δ; final visit, -2.8^Δ ± 3.4^Δ and -13.4^Δ ± 6.5^Δ, for distance and near, resp.; both P < 0.05 vs preoperative). Although some regression was observed compared to 1-2 weeks postoperatively, final exotropia was reduced compared to preoperative levels. Temporary overcorrection was observed in 5 cases, with plication suture removal required in one of them. Ultimately, the overcorrection resolved, and orthophoria was maintained.

Medial rectus plication improved ocular alignment in this small cohort of patients with small-angle convergence insufficiency-type exotropia. Its reversibility and lower risk profile compared with traditional approaches underscore its potential as a treatment option.