Surgical Outcomes of Patients with Intermittent Exotropia Exhibiting High Hyperopia and Emmetropia

Purpose: We analyzed the clinical factors and surgical outcomes of patients with intermittent exotropia exhibiting high hyperopia and emmetropia. Methods: Patients with intermittent exotropia who underwent strabismus surgery and were followed-up for at least one year between April 1999 and January 2018 were retrospectively reviewed. The patients were divided into two groups according to their preoperative spherical equivalent refractive error (SERE): a high hyperopia group (>=+4.00 diopters [D], group 1) and an emmetropia group (+0.50 to -0.50 D, group 2). The surgical outcomes of the groups were compared. Results: We enrolled 74 patients, of whom 24 and 50 were included in groups 1 and 2, respectively. In group 1, the mean SERE was +5.00 D (+4.00 to +8.00 D) in the more affected eye and +2.81 D (+0.00 to +7.25 D) in the better eye. In group 1, the changes in SERE at one year after surgery were as follows: +1.24 D in the worse eye and +0.90 D in the better eye (both, p < 0.001). The mean exodeviation at one day postoperatively for distance and near were -1.25 prism diopters (PD) and 0.21 PD, respectively, in group 1, and -4.62 PD and -2.16 PD in group 2. Thus, group 1 exhibited less exodeviation in terms of both distance and near than did group 2 on day one postoperatively. However, no significant group difference was evident at one year postoperatively. Conclusions: The surgical outcomes of intermittent exotropia patients with high hyperopia did not differ from those of patients with emmetropia.