title: Posterior fossa dural arteriovenous fistulas: diagnosis and follow-up with time-resolved imaging of contrast kinetics (TRICKS) at 1.5T.
abstract: BACKGROUND
  Time-of-flight MR angiography (TOF MRA) is currently the most widely used non-invasive imaging tool to diagnose dural arteriovenous fistula (DAVF). It is, however, not as sensitive as invasive digital subtraction angiography (DSA) for detecting the arteriovenous shunting inherent in DAVF. Dynamic contrast-enhanced MR angiography allows separation of arterial and venous phases of contrast passage though the brain and can thus demonstrate early venous filling through the arteriovenous shunt.
  
  
  OBJECTIVE
  To compare the diagnostic value of TOF MRA and a commercially available dynamic contrast-enhanced MR angiography sequence (TRICKS) at 1.5T in detecting posterior fossa DAVF.
  
  
  METHODS
  We retrospectively collected image data for 19 patients who underwent TOF MRA, TRICKS, and DSA either for primary diagnosis or for follow-up of posterior fossa DAVF and assessed the performance of TOF MRA and TRICKS in demonstrating the arteriovenous shunt, with DSA as the reference standard.
  
  
  RESULTS
  TRICKS detected early arterial filling at 94.4% sensitivity and 83.3% specificity. TOF MRA detected high flow-related signal within venous structures at 64.7% sensitivity and 80% specificity.
  
  
  CONCLUSIONS
  The commercially available dynamic MR angiography sequence TRICKS with fully automatic vendor postprocessing at 1.5T is more sensitive than TOF MRA in detecting the arteriovenous shunt in posterior fossa DAVF.
authors.affiliation: Helsinki Medical Imaging Center, Helsinki University Central Hospital, Finland. johanna.pekkola@hus.fi
authors.forename: Johanna
authors.initials: J
authors.lastname: Pekkola
authors.forename: Marko
authors.initials: M
authors.lastname: Kangasniemi
mesh_terms: D000328:Adult; D015901:Angiography, Digital Subtraction; D020785:Central Nervous System Vascular Malformations / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity