title: Comparison of long-term surgical outcomes of 2-muscle surgery in children with large-angle exotropia: bilateral vs unilateral.
abstract: OBJECTIVE
  To evaluate the long-term results of 2-muscle surgery in children with primary large-angle exotropia, comparing 10 mm bilateral lateral rectus recession (BLR) with unilateral lateral rectus recession-medial rectus resection (recess/resect).
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Eighty-six children with exotropia of ≥40 prism diopters (PD), who underwent the 10 mm BLR (BLR group) or the unilateral recess/resect procedure (RR group) based on the largest angle measured at distance or near were included. Patients were followed-up for more than 2 years. Final successful alignment rates, stereopsis, and factors related to recurrence and overcorrection were evaluated.
  
  
  RESULTS
  At the final examination, 29 (60.4%) of 48 patients in the BLR group achieved successful alignment; 16 (33.3%) had recurrence, and 3 (6.3%) had overcorrection. In the RR group, 26 of 38 patients (68.4%) were successfully aligned, 10 (26.3%) had recurrence, and 2 (5.3%) had overcorrection. Successful alignment and recurrence rates were not significantly different in the groups (P = .371 and .640, respectively). The overcorrection rate was significantly higher in the RR group (P = .014) until 2 years after surgery, but this difference was not significant afterward (P = 1.000). In patients with an exodeviation of ≥45 PD, the recess/resect procedure showed higher successful alignment rates at the final examination (P = .006).
  
  
  CONCLUSIONS
  The long-term successful alignment rate of 2-muscle surgery in children with primary large-angle exotropia was 64%, and the overall surgical outcomes were comparable between the BLR and RR groups. However, in patients with exotropia of ≥45 PD, the unilateral recess/resect procedure resulted in more favorable long-term outcomes.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, South Korea; Department of Ophthalmology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Ko Eun
authors.initials: KE
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, South Korea; Department of Ophthalmology, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, South Korea; Department of Ophthalmology, Seoul National University Bundang Hospital, Seongnam, South Korea. Electronic address: hjm@snu.ac.kr.
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Hwang
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003867:Depth Perception / Q000502:physiology; D005099:Exotropia / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009801:Oculomotor Muscles / Q000503:physiopathology / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures; D011183:Postoperative Complications; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D015348:Vision, Binocular / Q000502:physiology