title: Number and location of draining veins in pediatric arteriovenous malformations: association with hemorrhage.
abstract: OBJECTIVE
  The significance of draining vein anatomy is poorly defined in pediatric arteriovenous malformations (AVMs). In adult cohorts, the presence of fewer veins has been shown to lead to an increased rate of hemorrhage, but this phenomenon has not yet been studied in pediatric AVMs. This report analyzes the impact of draining vein anatomy on presentation and outcome in a large series of pediatric AVMs.
  
  
  METHODS
  Eighty-five pediatric patients with AVMs were treated at the Columbia University Medical Center between 1991 and 2012. Charts were retrospectively reviewed for patient characteristics, clinical course, neurological outcome, and AVM angioarchitectural features identified on the angiogram performed at presentation. Univariate analyses were performed using chi-square test and ANOVA when appropriate; multivariate analysis was performed using logistic regression.
  
  
  RESULTS
  Four patients were excluded due to incomplete records. Twenty-seven patients had 2 or 3 draining veins; 12 (44.4%) of these patients suffered from hemorrhage prior to surgery. Fifty-four patients had 1 draining vein; 39 (72.2%) of these 54 suffered from hemorrhage. Independent predictors of hemorrhage included the presence of a single draining vein (p = 0.04) and deep venous drainage (p = 0.02). Good outcome (modified Rankin Scale [mRS] score < 3) on discharge was found to be associated with higher admission Glasgow Coma Scale (GCS) scores (p = 0.0001, OR 0.638, 95% CI 0.40-0.93). Poor outcome (mRS score > 2) on discharge was found to be associated with deep venous drainage (p = 0.04, OR 4.68, 95% CI 1.1-19.98). A higher admission GCS score was associated with a lower discharge mRS score (p = 0.0003, OR 0.6, 95% CI 0.46-0.79), and the presence of a single draining vein was associated with a lower mRS score on long-term follow-up (p = 0.04, OR 0.18, 95% CI 0.032-0.99).
  
  
  CONCLUSIONS
  The authors' data suggest that the presence of a single draining vein or deep venous drainage plays a role in hemorrhage risk and ultimate outcome in pediatric AVMs. Small AVMs with a single or deep draining vein may have the highest risk of hemorrhage.
authors.affiliation: Department of Neurological Surgery, Columbia University, New York, New York.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Kellner
authors.forename: Michael M
authors.initials: MM
authors.lastname: McDowell
authors.forename: Michelle Q
authors.initials: MQ
authors.lastname: Phan
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
authors.forename: Sean D
authors.initials: SD
authors.lastname: Lavine
authors.forename: Philip M
authors.initials: PM
authors.lastname: Meyers
authors.forename: Daniel
authors.initials: D
authors.lastname: Sahlein
authors.forename: Robert A
authors.initials: RA
authors.lastname: Solomon
authors.forename: Neil A
authors.initials: NA
authors.lastname: Feldstein
authors.forename: Richard C E
authors.initials: RC
authors.lastname: Anderson
mesh_terms: D000293:Adolescent; D002543:Cerebral Hemorrhage / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D004322:Drainage; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D007223:Infant; D002538:Intracranial Arteriovenous Malformations / Q000150:complications* / Q000473:pathology* / Q000601:surgery; D016015:Logistic Models; D008297:Male; D012189:Retrospective Studies; D012306:Risk
keywords: AVM = arteriovenous malformation; GCS = Glasgow Coma Scale; arteriovenous malformation; draining veins; intracerebral hemorrhage; mRS = modified Rankin Scale; pediatrics; vascular disorders