Bilateral Medial Rectus Recession Posterior to the Functional Equator in Esotropia Over 40 Prism Diopters

ABSTRACT

PURPOSE: To investigate bilateral medial rectus recession by considering functional equator as a surgical guideline in esotropia over 40 prism diopters (PD). METHODS: Forty-one patients who underwent bilateral medial rectus recession, and were followed-up for more than 12 months, were reviewed. The success rate was compared between group 1 and group 2, which were divided to recession site from the functional equator posterior, and also between the hyperopia group and myopia group according to refraction. RESULTS: According to preoperative deviation angle, 21 patients underwent recession to less than 10 mm posterior to the functional equator (group 1) and 20 patients had recession to 1.5 mm to 2.0 mm posterior to the functional equator (group 2). No significant difference in success rate between group 1 (71.4%) and group 2 (75.0%) was detected at the last follow-up. When divided into a hyperopia group (26 patients) and myopia group (15 patients), the success rate in the myopia group was higher than in the hyperopia group, as observed at the last follow-up, but the difference was not significant. There was 1 case of overcorrection in each group. CONCLUSIONS: A successful outcome was achieved in 30 patients (73.2%), and overcorrection in 2 patients (4.9%) when recessed to 2.0 mm posterior to functional posterior in esotropia over 40PD.