Surgical Outcomes of Intermittent Exotropia as a Function of Strabismic Angle

Purpose: To analyze postoperative results of intermittent exotropia as a function of the difference in strabismic angles measured immediately and another time prior to the surgery. Methods: We reviewed the clinical records of intermittent exotropia patients who received surgery and had differences greater than or equal to 10 prism diopters (PD) between the last preoperative measurement of strabismic angle and another previous measurement. After applying various exclusion criteria, 66 patients were entered into our study. At the last follow-up visit after surgery, we divided postoperative results into 3 categories: (1) poor; with greater than 10 PD of esotropia or angle of exodeviation of 20 PD or more (2) moderate; with 6-10 PD of esophoria/tropia or 10-19 PD exodeviation, or (3) good; with 1-5 PD of esophoria / tropia or an angle of exodeviation less than 10 PD, or orthophoria. Results: Good results were higher in patients where the difference in strabismic angle was 10 PD or greater between the last measurement and any other earlier measurement. Conclusions: In cases of Intermittent exotropia where the last preoperative value of strabismic angle was greater than any previous preoperative measurement, surgical dosage based on the last preoperative measurement yielded better results.