title: Association of infratentorial brain arteriovenous malformations with hemorrhage at initial presentation.
abstract: OBJECTIVE
  The goal of this study was to analyze the association of hemorrhagic presentation with infratentorial brain arteriovenous malformations (AVMs).
  
  
  METHODS
  The 623 consecutive, prospectively enrolled patients from the Columbia AVM Databank were analyzed in a cross-sectional study. Clinical presentation (diagnostic event) was categorized as intracranial hemorrhage or nonhemorrhagic presentation. From brain imaging and cerebral angiography, AVM location was classified as either infratentorial or supratentorial. Univariate and multivariate statistical models were applied to test the effect of age, sex, AVM size and location, venous drainage pattern, and associated (ie, feeding artery or intranidal) arterial aneurysms on the likelihood of hemorrhage at initial AVM presentation.
  
  
  RESULTS
  Of the 623 patients, 72 (12%) had an infratentorial and 551 (88%) had a supratentorial AVM. Intracranial hemorrhage was the presenting symptom in 283 patients (45%), and infratentorial AVM location was significantly more frequent (18%) among patients who bled initially (6%; odds ratio [OR], 3.60; 95% confidence interval [CI], 2.09 to 6.20). This difference remained significant (OR, 1.99; 95% CI, 1.07 to 3.69) in the multivariate logistic regression model controlling for age, sex, AVM size, deep venous drainage, and associated arterial aneurysms. In the same model, the effect of other established determinants for AVM hemorrhage--ie, AVM size (in 1-mm increments; OR, 0.95; 95% CI, 0.94 to 0.96), deep venous drainage (OR, 3.09; 95% CI, 1.87 to 5.12), and associated aneurysms (OR, 2.78; 95% CI, 1.76 to 4.40)--remained significant.
  
  
  CONCLUSIONS
  Our findings suggest that infratentorial AVM location is independently associated with hemorrhagic AVM presentation.
authors.affiliation: Stroke Center, Neurological Institute, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA. akhaw@neuro.columbia.edu
authors.forename: A V
authors.initials: AV
authors.lastname: Khaw
authors.forename: J P
authors.initials: JP
authors.lastname: Mohr
authors.forename: R R
authors.initials: RR
authors.lastname: Sciacca
authors.forename: H C
authors.initials: HC
authors.lastname: Schumacher
authors.forename: A
authors.initials: A
authors.lastname: Hartmann
authors.forename: J
authors.initials: J
authors.lastname: Pile-Spellman
authors.forename: H
authors.initials: H
authors.lastname: Mast
authors.forename: C
authors.initials: C
authors.lastname: Stapf
mesh_terms: D000328:Adult; D000367:Age Factors; D001933:Brain Stem / Q000098:blood supply; D002531:Cerebellum / Q000098:blood supply; D002533:Cerebral Angiography; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000175:diagnosis* / Q000453:epidemiology; D020300:Intracranial Hemorrhages / Q000175:diagnosis* / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009518:New York / Q000453:epidemiology; D016017:Odds Ratio; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors