title: Flow and pressure measurements in aneurysms and arteriovenous malformations with phase contrast MR imaging.
abstract: To explore phase contrast (PC) magnetic resonance imaging of aneurysms and arteriovenous malformations (AVM). PC imaging obtains a vector field of the velocity and can yield additional hemodynamic information, including: volume flow rate (VFR) and intravascular pressure. We expect to find lower VFR distal to aneurysms and higher VFR in vessels of the AVM.
  
  
  
  Five cerebral aneurysm and three AVM patients were imaged with PC techniques and compared to VFR of a healthy cohort. VFR was calculated in vessel segments in each patient and compared statistically to the healthy cohort by computing the z-score. Intravascular pressure was calculated in the aneurysms and in the nidus of each AVM.
  
  
  
  We found that patients with aneurysm had z<-0.48 in vessels distal to the aneurysm (reduced flow), while AVM patients had z>6 in some vessels supplying and draining the nidus (increased flow). Pressures in aneurysms were highly variable between subjects and location, while in the nidus of the AVM patients; pressure trended higher in larger AVMs.
  
  
  
  The study findings confirm the expectation of lower distal flow in aneurysm and higher arterial and venous flow in AVM patients.
authors.affiliation: Biomedical Engineering, University of Calgary, Calgary, AB, Canada; Radiology, University of Calgary, Calgary, AB, Canada; Clinical Neuroscience, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family Magnetic Resonance Research Centre, Foothills Medical Centre, Calgary, AB, Canada. Electronic address: matthewethanmacdonald@gmail.com.
authors.forename: M Ethan
authors.initials: ME
authors.lastname: MacDonald
authors.affiliation: Radiology, University of Calgary, Calgary, AB, Canada; Clinical Neuroscience, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family Magnetic Resonance Research Centre, Foothills Medical Centre, Calgary, AB, Canada.
authors.forename: Parviz
authors.initials: P
authors.lastname: Dolati
authors.affiliation: Radiology, University of Calgary, Calgary, AB, Canada; Clinical Neuroscience, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family Magnetic Resonance Research Centre, Foothills Medical Centre, Calgary, AB, Canada.
authors.forename: Alim P
authors.initials: AP
authors.lastname: Mitha
authors.affiliation: Radiology, University of Calgary, Calgary, AB, Canada; Clinical Neuroscience, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family Magnetic Resonance Research Centre, Foothills Medical Centre, Calgary, AB, Canada.
authors.forename: John H
authors.initials: JH
authors.lastname: Wong
authors.affiliation: Biomedical Engineering, University of Calgary, Calgary, AB, Canada; Radiology, University of Calgary, Calgary, AB, Canada; Clinical Neuroscience, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Seaman Family Magnetic Resonance Research Centre, Foothills Medical Centre, Calgary, AB, Canada. Electronic address: rfrayne@ucalgary.ca.
authors.forename: Richard
authors.initials: R
authors.lastname: Frayne
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: AVM; Cerebral aneurysm; Flow imaging; Intravascular pressure; VFR