title: Intraoperative traction testing to detect incomplete inferior oblique myotomy/myectomy.
abstract: OBJECTIVE
  Incomplete transection of the inferior oblique muscle during myotomy or myectomy is an important preventable cause of ineffective inferior oblique weakening surgery. Intraoperative traction testing has been suggested as a means of detecting an incomplete inferior oblique transection. The usefulness of intraoperative traction testing to detect incomplete myotomy was evaluated.
  
  
  METHODS
  The subjective "tightness" of the inferior oblique muscle was evaluated after partial and complete myotomy to determine how partial myotomy affected inferior oblique traction testing and to determine whether intraoperative traction testing is an effective means of ensuring that a complete myotomy has been achieved. Serial traction testing was performed on 10 inferior oblique muscles at the time of myotomy and scored, 0+ to 4+ tightness. Testing was performed before myotomy and after 50%, 90%, and total myotomy.
  
  
  RESULTS
  In 8 of 10 eyes traction testing remained strongly positive until the inferior oblique muscle had been completely transected. The average inferior oblique muscle tightness of these eight muscles was +1.69 before myotomy and after 50% and 90% myotomy. The tightness decreased to 0 after 100% myotomy. In two cases no inferior oblique muscle could be detected after 50% and 90% myotomy, respectively. These two muscles had preoperative traction testing of +0.5 and +1.00, respectively.
  
  
  CONCLUSIONS
  Intraoperative traction testing is a practical and effective method of detecting incomplete inferior oblique myotomy/myectomy, but the test should be interpreted with caution in patients with loose premyotomy muscles.
authors.affiliation: Cullen Eye Institute, Baylor College of Medicine, Texas Children's Hospital, Houston 77030, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Coats
authors.forename: E A
authors.initials: EA
authors.lastname: Paysse
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008488:Medical Illustration; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000601:surgery*; D013536:Suture Techniques; D014143:Traction; D016896:Treatment Outcome