Abstract:AIM: To evaluate the relation between preoperative hyperopia and surgical outcomes of infantile esotropia in patients younger than 24 months of age. METHODS: Medical records of patients who underwent bilateral medial rectus muscle recession for infantile esotropia between November 1, 2002 and December 1, 2011 were retrospectively reviewed. Patients were divided into two groups according to the degree of preoperative hyperopia. Group I had less than +3.0 diopter (D) of hyperopia and group II had between +3.0 and +5.0 D of hyperopia. Postoperative alignments were evaluated 1wk, 3, 6mo, and 1y after surgery. Following the 1-year postoperative visit, patients were monitored yearly. Relationships between preoperative factors including hyperopia and postoperative outcomes were evaluated. RESULTS: Forty-six patients were included, with 33 patients in group I and 13 patients in group II. The preoperative mean refractive error was +0.88 D in group I and +3.45 D in group II. Surgical outcomes were not significantly different between groups at any postoperative time point examined. Cumulative probability of surgical success, prevalence of inferior oblique overaction, dissociated vertical deviation, and re-operation rate were not significantly different between groups. CONCLUSION: Preoperative moderate hyperopia (less than +5.0 D) did not affect the surgical outcome of infantile esotropia. Therefore, the surgical correction of esotropia should be considered when the angle of esodeviation is unchanged following hyperopia correction, even in children with moderate hyperopia.