Analysis of Postoperative Outcomes in Patients with Intermittent Exotropia According to Preoperative Change of Angle of Deviation

Purpose: The correlation between the existence of the preoperative condition of ≥10 prism diopters (PD) in patients withbasic type of intermittent exotropia (IXT) and postoperative outcomes was analyzed. Methods: The medical records of patients that underwent surgery for IXT were analyzed retrospectively. The analysis wasconducted by dividing the patients into a group with change of <10 PD (group 1) and ≥10 PD (group 2) before the time of thesurgery. Patients who received at least 6 months of follow-up after surgery were included. The age, sex, angle of deviationand stereoacuity of the patients were studied. Surgical success was defined as exodeviation of <10 PD or esodeviation of <4PD at the final visit after the surgery. The correlation between clinical factors and surgical success rate was analyzed by usingcorrelative analysis. Results: A total of 129 patients participated in the study. There were 108 (83.7%) and 21 (16.3%) patients in groups 1 and 2,respectively. There were 89 (82.4%) and 17 (80.1%) patients with surgical successes in groups 1 and 2, respectively (p = 0.18). Moreover, 13 (12.0%) patients in group 1 and three (14.3%) patients in group 2 required reoperation, showing no significantdifference (p = 0.12). There was no statistically significant correlation between surgical success and preoperative change ofangle of deviation <10 PD (odds ratio, 1.78; p = 0.17). Conclusions: Among the patients with basic type of IXT subjected to the analysis, 16.3% had a change of ≥10 PD before surgery,and there was no significant correlation between surgical success and preoperative change of angle of deviation.