Factors affecting surgical outcome of intermittent exotropia

PURPOSE: The purpose of this study was to investigate the factors affecting surgical outcome in intermittent exotropia. DESIGNS: This was a retrospective interventional study. METHODS: Intermittent exotropic patients who had undergone surgical correction with a postoperative follow-up period of 1 month or more were included in the study. Surgical success was defined as an alignment between 10 prism diopters (PD) of exotropia or 5 PD of esotropia at 1 month. After data collection, data were analyzed in SPSS version 23 software. The main outcome measures were the factors affecting surgical outcome. RESULTS: We included 101 patients, including 52 (51.5%) male and 49 (48.5%) female. Among them, 62 (61.4%) patients achieved surgical success. Undercorrection was the primary reason of surgical failure. Multivariate regression analysis showed that a larger preoperative angle of deviation was associated with unfavorable surgical outcome (P = 0.053, odds ratio [OR] =0.97, 95% confidence interval [CI] = 0.94-1.00), and the presence of postoperative day 1 (POD 1) diplopia correlated significantly with higher surgical success (P = 0.001, OR = 4.54, 95% CI = 1.80-11.43). The presence of POD 1 diplopia was highly associated with POD 1 esotropia (P = 0.005, OR = 7.26, 95% CI = 1.84-28.58). CONCLUSION: In intermittent exotropia, larger preoperative angle of deviation may predict a lower surgical success rate. Despite a worrisome issue, the presence of diplopia on first POD is associated with immediate postoperative alignment of esotropia and predicts a higher surgical success.