title: Effect of muscle relaxants on short-term results of exotropia surgery: a focus on resection procedures.
abstract: OBJECTIVE
  We investigated the effect of muscle relaxants (atracurium) on the outcomes of intermittent exotropia surgery under general anesthesia, with a focus on resection procedures.
  
  
  METHODS
  Thirty four patients who underwent recession and resection (R&R) were divided into two groups: atracurium usage (group A, n=18) and no atracurium usage (group B, n=16). Patients were divided into two subgroups according to the amount of resection of the medial rectus (MR): less than 5 mm (group 1, n=13) or 5 mm and greater (group 2, n=21). Deviation angles were compared between groups and subgroups. Surgical outcome was defined as successful if distant deviation angles were equal to or less than 10 prism diopters.
  
  
  RESULTS
  The overall postoperative deviation angles did not show statistically significant differences between groups A and B. However, in patients with larger MR resections (> or = 5 mm), the 1 week postoperative distant deviation was significantly larger in group A (1.8+/-2.6 PD) than in group B (-1.6+/-4.6 PD, p=0.048 by t-test). The overall undercorrection rate at 3 months postoperatively for group A was 16.7%, which was higher than that of group B (6.3%), and the difference was even larger in subgroups with larger MR resections (> or = 5 mm): 18.2% in group A and 0% in group B.
  
  
  CONCLUSIONS
  Patients who underwent R&R procedures under general anesthesia with a muscle relaxant tended to be less corrected than those without muscle relaxant, especially in the early postoperative period and with a larger MR resection equal to or greater than 5 mm. However, there was no significant difference in the later postoperative period.
authors.affiliation: Department of Ophthalmology, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
authors.forename: Young-Suk
authors.initials: YS
authors.lastname: Chang
authors.forename: Seung-Hee
authors.initials: SH
authors.lastname: Baek
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Park
authors.forename: Hee-Uk
authors.initials: HU
authors.lastname: Kwon
authors.forename: Yong-Ran
authors.initials: YR
authors.lastname: Kim
mesh_terms: D000769:Anesthesia, Inhalation; D001279:Atracurium / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D005099:Exotropia / Q000503:physiopathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D009126:Muscle Relaxation; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage*; D009801:Oculomotor Muscles / Q000503:physiopathology*; D013508:Ophthalmologic Surgical Procedures; D016896:Treatment Outcome
chemical_list: D003473:Neuromuscular Nondepolarizing Agents; D001279:Atracurium