title: Microsurgery for cerebral arteriovenous malformations: postoperative outcomes and predictors of complications in 264 cases.
abstract: OBJECTIVE
  The authors conducted a study to assess the safety and efficacy of microsurgical resection of arteriovenous malformations (AVMs) and determine predictors of complications.
  
  
  METHODS
  A total of 264 patients with cerebral AVMs were treated with microsurgical resection between 1994 and 2010 at the Jefferson Hospital for Neuroscience. A review of patient data was performed, including initial hemorrhage, clinical presentation, Spetzler-Martin (SM) grade, treatment modalities, clinical outcomes, and obliteration rates. Univariate and multivariate analyses were used to determine predictors of operative complications.
  
  
  RESULTS
  Of the 264 patients treated with microsurgery, 120 (45%) patients initially presented with hemorrhage. There were 27 SM Grade I lesions (10.2%), 101 Grade II lesions (38.3%), 96 Grade III lesions (36.4%), 31 Grade IV lesions (11.7%), and 9 Grade V lesions (3.4%). Among these patients, 102 (38.6%) had undergone prior endovascular embolization. In all patients, resection resulted in complete obliteration of the AVM. Complications occurred in 19 (7.2%) patients and resulted in permanent neurological deficits in 5 (1.9%). In multivariate analysis, predictors of complications were increasing AVM size (OR 3.2, 95% CI 1.5-6.6; p = 0.001), increasing number of embolizations (OR 1.6, 95% CI 1.1-2.2; p = 0.01), and unruptured AVMs (OR 2.7, 95% CI 1-7.2; p = 0.05).
  
  
  CONCLUSIONS
  Microsurgical resection of AVMs is highly efficient and can be undertaken with low rates of morbidity at high-volume neurovascular centers. Unruptured and larger AVMs were associated with higher complication rates.
authors.affiliation: Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania.
authors.forename: Thana
authors.initials: T
authors.lastname: Theofanis
authors.forename: Nohra
authors.initials: N
authors.lastname: Chalouhi
authors.forename: Richard
authors.initials: R
authors.lastname: Dalyai
authors.forename: Robert M
authors.initials: RM
authors.lastname: Starke
authors.forename: Pascal
authors.initials: P
authors.lastname: Jabbour
authors.forename: Robert H
authors.initials: RH
authors.lastname: Rosenwasser
authors.forename: Stavropoula
authors.initials: S
authors.lastname: Tjoumakaris
mesh_terms: D000328:Adult; D000368:Aged; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D008297:Male; D008866:Microsurgery / Q000592:standards*; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: AVM = arteriovenous malformation; SM = Spetzler-Martin; Spetzler-Martin grade; arteriovenous malformation; embolization; endovascular; mRS = modified Rankin Scale; microsurgery