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 diopter (PD) in patients with basic type of intermittent exotropia (IXT) and postoperative outcomes was analyzed. Method The medical records of patients that underwent surgery for IXT were analyzed retrospectively. The analysis was conducted by dividing the patients into a group with change of < 10 PD (Group 1) and ≥ 10 PD (Group 2) before the time of the surgery. Patients who received at least 6 months of follow-up after surgery were included. The age, sex, angle of deviation and stereoacuity of the patients were studied. Surgical success was defined as exodeviation of < 10 PD or esodeviation of < 4 PD at the final visit after the surgery. The correlation between clinical factors and surgical success rate was analyzed by using correlative 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 3 (14.3%) patients in Group 2 required reoperation, showing no significant difference (p = 0.12). There was no statistically significant correlation between surgical success and preoperative change of angle of deviation < 10 PD (OR = 1.78, p = 0.17). Conclusion 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.