title: Laser Doppler velocimetry (LDV) and 3D phase-contrast magnetic resonance angiography (PC-MRA) velocity measurements: validation in an anatomically accurate cerebral artery aneurysm model with steady flow.
abstract: OBJECTIVE
  To verify the accuracy of velocity mapping with three-dimensional (3D) phase-contrast magnetic resonance angiography (PC-MRA) for steady flow in a realistic model of a cerebral artery aneurysm at a 3T scanner.
  
  
  METHODS
  Steady flow through an original geometry model of a cerebral aneurysm was mapped at characteristic positions by state-of-the-art laser Doppler velocimetry (LDV) as well as 3D PC-MRA at 3T. The spatial distributions and local values of two velocity components obtained with these two measurement methods were compared.
  
  
  RESULTS
  The 3D PC-MRA velocity field distribution and mean velocity values exhibited only minor differences to compare to the LDV measurements in straight artery regions for both main and secondary velocities. The differences increased in regions with disturbed flow and in cases where the measurement plane was not perpendicular to the main flow direction.
  
  
  CONCLUSIONS
  3D PC-MRA can provide reliable measurements of velocity components of steady flow in small arteries. The accuracy of such measurements depends on the artery size and the measurement plane positioning.
authors.affiliation: Laboratory of Thermodynamics in Emerging Technologies, ETH Zurich, Zurich, Switzerland.
authors.forename: Dorothea I
authors.initials: DI
authors.lastname: Hollnagel
authors.forename: Paul E
authors.initials: PE
authors.lastname: Summers
authors.forename: Spyros S
authors.initials: SS
authors.lastname: Kollias
authors.forename: Dimos
authors.initials: D
authors.lastname: Poulikakos
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D002533:Cerebral Angiography / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008955:Models, Cardiovascular; D012044:Regression Analysis