title: Dural arteriovenous shunts: a new classification of craniospinal epidural venous anatomical bases and clinical correlations.
abstract: OBJECTIVE
  The craniospinal epidural spaces can be categorized into 3 different compartments related to their specific drainage role of the bone and central nervous system, the ventral epidural, dorsal epidural, and lateral epidural groups. We propose this new classification system for dural arteriovenous shunts and compare demographic, angiographic, and clinical characteristics of dural arteriovenous shunts that develop in these 3 different locations.
  
  
  METHODS
  Three hundred consecutive cases (159 females, 141 males; mean age: 47 years; range, 0 to 87 years) were reviewed for patient demographics, clinical presentation, multiplicity, presence of cortical and spinal venous reflux, and outflow restrictions and classified into the 3 mentioned groups.
  
  
  RESULTS
  The ventral epidural group (n=150) showed a female predominance, more benign clinical presentations, lower rate of cortical and spinal venous reflux, and no cortical and spinal venous reflux without restriction of the venous outflow. The dorsal epidural group (n=67) had a lower mean age and a higher rate of multiplicity. The lateral epidural group (n=63) presented later in life with a male predominance, more aggressive clinical presentations, and cortical and spinal venous reflux without evidence of venous outflow restriction. All differences were statistically significant (P<0.001).
  
  
  CONCLUSIONS
  Dural arteriovenous shunts predictably drain either in pial veins or craniofugally depending on the compartment involved by the dural arteriovenous shunt. Associated conditions (outflow restrictions, high-flow shunts) may change that draining pattern. The significant differences between the groups of the new classification support the hypothesis of biological and/or developmental differences in each epidural region and suggest that dural arteriovenous shunts are a heterogeneous group of diseases.
authors.affiliation: Department of Radiology, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Sasikhan
authors.initials: S
authors.lastname: Geibprasert
authors.forename: Vitor
authors.initials: V
authors.lastname: Pereira
authors.forename: Timo
authors.initials: T
authors.lastname: Krings
authors.forename: Pakorn
authors.initials: P
authors.lastname: Jiarakongmun
authors.forename: Frederique
authors.initials: F
authors.lastname: Toulgoat
authors.forename: Sirintara
authors.initials: S
authors.lastname: Pongpech
authors.forename: Pierre
authors.initials: P
authors.lastname: Lasjaunias
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply / Q000473:pathology; D020785:Central Nervous System Vascular Malformations / Q000145:classification* / Q000473:pathology* / Q000503:physiopathology*; D002533:Cerebral Angiography; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012737:Sex Factors; D013116:Spinal Cord / Q000098:blood supply / Q000473:pathology