title: The American Society of Anesthesiologists Postoperative Visual Loss Registry: analysis of 93 spine surgery cases with postoperative visual loss.
abstract: BACKGROUND
  Postoperative visual loss after prone spine surgery is increasingly reported in association with ischemic optic neuropathy, but its etiology is unknown.
  
  
  METHODS
  To describe the clinical characteristics of these patients, the authors analyzed a retrospectively collected series of 93 spine surgery cases voluntarily submitted to the American Society of Anesthesiologists Postoperative Visual Loss Registry on standardized data forms.
  
  
  RESULTS
  Ischemic optic neuropathy was associated with 83 of 93 spine surgery cases. The mean age of the patients was 50 +/- 14 yr, and most patients were relatively healthy. Mayfield pins supported the head in 16 of 83 cases. The mean anesthetic duration was 9.8 +/- 3.1 h, and the median estimated blood loss was 2.0 l (range, 0.1-25 l). Bilateral disease was present in 55 patients, with complete visual loss in the affected eye(s) in 47. Ischemic optic neuropathy cases had significantly higher anesthetic duration, blood loss, percentage of patients in Mayfield pins, and percentage of patients with bilateral disease compared with the remaining 10 cases of visual loss diagnosed with central retinal artery occlusion (P < 0.05), suggesting they are of different etiology.
  
  
  CONCLUSIONS
  Ischemic optic neuropathy was the most common cause of visual loss after spine surgery in the Registry, and most patients were relatively healthy. Blood loss of 1,000 ml or greater or anesthetic duration of 6 h or longer was present in 96% of these cases. For patients undergoing lengthy spine surgery in the prone position, the risk of visual loss should be considered in the preoperative discussion with patients.
authors.affiliation: Departments of Anesthesiology and Neurological Surgery (Adjunct), University of Washington, Harborview Medical Center, 325 Ninth Avenue, Seattle, WA 98104, USA. lorlee@u.washington.edu
authors.forename: Lorri A
authors.initials: LA
authors.lastname: Lee
authors.forename: Steven
authors.initials: S
authors.lastname: Roth
authors.forename: Karen L
authors.initials: KL
authors.lastname: Posner
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Cheney
authors.forename: Robert A
authors.initials: RA
authors.lastname: Caplan
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Newman
authors.forename: Karen B
authors.initials: KB
authors.lastname: Domino
mesh_terms: D000758:Anesthesia / Q000009:adverse effects*; D016063:Blood Loss, Surgical / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*; D011187:Posture; D012042:Registries; D015203:Reproducibility of Results; D012307:Risk Factors; D013131:Spine / Q000601:surgery*; D014786:Vision Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*