title: Dynamic measurements of total hepatic blood flow with Phase Contrast MRI.
abstract: OBJECTIVE
  To measure total hepatic blood flow including portal and proper hepatic artery flows as well as the temporal evolution of the vessel's section during a cardiac cycle.
  
  
  METHODS
  Twenty healthy subjects, with a mean age of 26 years, were explored. Magnetic resonance imaging blood flow measurements were carried out in the portal vein and the proper hepatic artery. MR studies were performed using a 1.5T imager (General Electric Medical Systems). Gradient-echo 2D Fast Cine Phase Contrast sequences were used with both cardiac and respiratory gatings. Data analysis was performed using a semi-automatic software built in our laboratory.
  
  
  RESULTS
  The total hepatic flow rate measured was 1.35+/-0.18L/min or 19.7+/-4.6mL/(minkg). The proper hepatic artery provided 19.1% of the total hepatic blood flow entering the liver. Those measurements were in agreement with earlier studies using direct measurements. Mean and maximum velocities were also assessed and a discrepancy between our values and the literature's Doppler data was found. Measurements of the portal vein area have shown a mean variation, defined as a "pulsatility" index of 18% over a cardiac cycle.
  
  
  CONCLUSIONS
  We report here proper hepatic artery blood flow rate measurements using MRI. Associated with portal flow measurements, we have shown the feasibility of total hepatic flowmetry using a non-invasive and harmless technique.
authors.affiliation: Department of Radiology, University Hospital, Place Victor Pauchet, 80054 Amiens cedex 1, France. Yzet.Thierry@chu-amiens.fr
authors.forename: Thierry
authors.initials: T
authors.lastname: Yzet
authors.forename: Roger
authors.initials: R
authors.lastname: Bouzerar
authors.forename: Olivier
authors.initials: O
authors.lastname: Baledent
authors.forename: Cedric
authors.initials: C
authors.lastname: Renard
authors.forename: Didier Mbayo
authors.initials: DM
authors.lastname: Lumbala
authors.forename: Eric
authors.initials: E
authors.lastname: Nguyen-Khac
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Regimbeau
authors.forename: H
authors.initials: H
authors.lastname: Deramond
authors.forename: Marc-Etienne
authors.initials: ME
authors.lastname: Meyer
mesh_terms: D000328:Adult; D005260:Female; D006499:Hepatic Artery / Q000033:anatomy & histology* / Q000502:physiology*; D006503:Hepatic Veins / Q000033:anatomy & histology* / Q000502:physiology*; D006801:Humans; D008102:Liver Circulation / Q000502:physiology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D055420:Perfusion Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity