title: Influence of Spatial Resolution in Three-dimensional Cine Phase Contrast Magnetic Resonance Imaging on the Accuracy of Hemodynamic Analysis.
abstract: BACKGROUND
  We aim to elucidate the effect of spatial resolution of three-dimensional cine phase contrast magnetic resonance (3D cine PC MR) imaging on the accuracy of the blood flow analysis, and examine the optimal setting for spatial resolution using flow phantoms.
  
  
  METHODS
  The flow phantom has five types of acrylic pipes that represent human blood vessels (inner diameters: 15, 12, 9, 6, and 3 mm). The pipes were fixed with 1% agarose containing 0.025 mol/L gadolinium contrast agent. A blood-mimicking fluid with human blood property values was circulated through the pipes at a steady flow. Magnetic resonance (MR) images (three-directional phase images with speed information and magnitude images for information of shape) were acquired using the 3-Tesla MR system and receiving coil. Temporal changes in spatially-averaged velocity and maximum velocity were calculated using hemodynamic analysis software. We calculated the error rates of the flow velocities based on the volume flow rates measured with a flowmeter and examined measurement accuracy.
  
  
  RESULTS
  When the acrylic pipe was the size of the thoracicoabdominal or cervical artery and the ratio of pixel size for the pipe was set at 30% or lower, spatially-averaged velocity measurements were highly accurate. When the pixel size ratio was set at 10% or lower, maximum velocity could be measured with high accuracy. It was difficult to accurately measure maximum velocity of the 3-mm pipe, which was the size of an intracranial major artery, but the error for spatially-averaged velocity was 20% or less.
  
  
  CONCLUSIONS
  Flow velocity measurement accuracy of 3D cine PC MR imaging for pipes with inner sizes equivalent to vessels in the cervical and thoracicoabdominal arteries is good. The flow velocity accuracy for the pipe with a 3-mm-diameter that is equivalent to major intracranial arteries is poor for maximum velocity, but it is relatively good for spatially-averaged velocity.
authors.affiliation: Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Fukuyama
authors.affiliation: Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine.|Brain & Mind Research Center, Nagoya University.
authors.forename: Haruo
authors.initials: H
authors.lastname: Isoda
authors.affiliation: Toyohashi Municipal Hospital.
authors.forename: Kento
authors.initials: K
authors.lastname: Morita
authors.affiliation: Gifu Prefectural General Medical Center.
authors.forename: Marika
authors.initials: M
authors.lastname: Mori
authors.affiliation: Kyoto University Hospital.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine.
authors.forename: Kenta
authors.initials: K
authors.lastname: Ishiguro
authors.affiliation: Siemens Healthcare K.K.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Komori
authors.affiliation: Renaissance of Technology Corporation.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kosugi
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D019047:Phantoms, Imaging / Q000592:standards*
keywords: hemodynamics; maximum velocity; spatial resolution; spatially-averaged velocity; three dimensional cine phase contrast magnetic resonance imaging