title: Hemodynamic changes in patients with arteriovenous malformations assessed using high-resolution 3D radial phase-contrast MR angiography.
abstract: OBJECTIVE
  Arteriovenous malformations have a high lifetime risk of hemorrhage; however, treatment carries a significant risk of morbidity and mortality, including permanent neurologic sequelae. WSS and other hemodynamic parameters are altered in patients with symptomatic AVMs, and analysis of hemodynamics may have value in stratifying patients into different risk groups. In this study, we examined hemodynamic data from patients with stable symptoms and those who presented with acute symptoms to identify trends which may help in risk stratification.
  
  
  METHODS
  Phase-contrast MRA using a radial readout (PC-VIPR) is a fast, high-resolution technique that can acquire whole-brain velocity-encoded angiograms with scan times of approximately 5 minutes. Ten patients with AVMs were scanned using PC-VIPR; velocity, area, flow, and WSS in vessels feeding the AVMs and normal contralateral vessels were calculated using velocity data from the phase-contrast acquisition.
  
  
  RESULTS
  Patients with an asymptomatic presentation or mild symptoms (n = 4) had no significant difference in WSS in feeding vessels compared with normal contralateral vessels, whereas patients presenting with hemorrhage, severe headaches/seizures, or focal neurologic deficits (n = 6) had significantly higher WSS in feeding vessels compared with contralateral vessels.
  
  
  CONCLUSIONS
  In this study, we demonstrate that estimates of WSS and other hemodynamic parameters can be obtained noninvasively in patients with AVMs in clinically useful imaging times. Variation in WSS between feeders and normal vessels appears to relate to the clinical presentation of the patient. Further analysis of hemodynamic changes may improve characterization and staging of AVM patients, when combined with existing risk factors.
authors.affiliation: Department of Medical Physics, University of Wisconsin, Madison, WI 53705, USA. wmchang2@wisc.edu
authors.forename: W
authors.initials: W
authors.lastname: Chang
authors.forename: M W
authors.initials: MW
authors.lastname: Loecher
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.forename: D B
authors.initials: DB
authors.lastname: Niemann
authors.forename: B
authors.initials: B
authors.lastname: Ciske
authors.forename: B
authors.initials: B
authors.lastname: Aagaard-Kienitz
authors.forename: S
authors.initials: S
authors.lastname: Kecskemeti
authors.forename: K M
authors.initials: KM
authors.lastname: Johnson
authors.forename: O
authors.initials: O
authors.lastname: Wieben
authors.forename: C
authors.initials: C
authors.lastname: Mistretta
authors.forename: P
authors.initials: P
authors.lastname: Turski
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D002536:Cerebral Arteries / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D020300:Intracranial Hemorrhages; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D033081:Shear Strength; D055815:Young Adult