Initial Postoperative Alignment in Strabismus Related to Thyroid Eye Disease

Purpose: To investigate the surgical outcome according to the initial postoperative angle of deviation in patients with thyroid eye disease. Methods: The medical records of patients who underwent strabismus surgery were retrospectively reviewed. The patients were divided into overcorrection (> 5 prism diopters [PD]), full correction, or undercorrection (> 5 PD) groups, according to the angle of deviation on postoperative day 1. The surgical outcome was considered successful when there was no diplopia vertically (< 5 PD) and horizontally (< 10 PD) at primary gaze. Surgical success rates were evaluated according to the initial postoperative angle of deviation at the final visit. Results: Seventy-eight patients were enrolled in this study. The mean age of the patients was 53.4 +/- 9.5 years, and the mean follow-up duration was 17.4 +/- 8.7 months. There were 51 patients with hypotropia and 27 patients with esotropia. Success rates for hypotropia were higher in the undercorrection (80.0%) and full correction (66.7%) groups than in the overcorrection (35.7%) group on postoperative day 1 (P= .02). Regarding esotropia, the success rates were higher in the undercorrection (84.6%) and full correction (83.3%) groups than in the overcorrection (37.5%) group on postoperative day 1 (P= .02). Reoperation for residual or overcorrected strabismus was performed in 15 patients (29.4%) with hypotropia and 7 patients (25.9%) with esotropia. Conclusions: Intended minimal undercorrection or full correction after hypotropia and esotropia surgery during early postoperative periods could improve surgical success rates in patients with thyroid eye disease.