Basic acquired nonaccommodative esotropia patients managed with surgery; a study of 2102 patients.

Introduction: Several studies investigated preoperative clinical features of patients with basic-acquired nonaccommodative esotropia (BANAET); however, their sample sizes were small, and they did not compare the clinical features among cases that needed different surgery times. The main purpose of this study is to compare the preoperative clinical features of patients with BANAET managed with one surgery with patients who underwent two or more strabismus surgery over 10 years.

Methods: This historical cohort study was performed on the hospital records of 13,252 Iranian strabismic patients who underwent surgery at Farabi eye hospital, Tehran, Iran, from 2012 to September 2022. Of those, 2102 cases with BANAET were selected as the sample size. Data collected included sex, age at the time of first surgery, corrected distance visual acuity (CDVA), refractive error, presence of amblyopia, angle of deviation, and times of surgery.

Results: The mean age was 18.9 ± 15.6 [1200 (57.1%) males and 902 (42.9%) females] and the median age was 14 years. In 1599 (76.1%) patients, esotropia was managed with one surgery; however, 342 (16.3%) cases were managed with two surgeries and 161 (7.6%) patients underwent three or more surgeries. The mean angle of horizontal deviation at distance and near in patients managed with two and ≥3 surgeries was significantly higher than in cases managed with one surgery (P < .001). Amblyopia was observed in 289 (18.1%) patients who were managed with one surgery, 69 (20.2%) patients with two surgeries and 43 (26.7%) patients with three or more surgeries (P < .001). Patients with BANAET managed successfully with only one surgery were younger, had better CDVA, lower astigmatism and less horizontal angle of deviation at distance and near than those who underwent two or more surgeries (all P < .001).

Discussion: The higher astigmatism, lower CDVA, greater angle of horizontal deviation, and higher frequency of amblyopia were found in the preoperative examinations of BANAET patients managed with two or more surgeries compared with cases managed with only one surgery.