title: Measurement of liver stiffness with two imaging techniques: magnetic resonance elastography and ultrasound elastometry.
abstract: OBJECTIVE
  To cross-validate the magnetic resonance elastography (MRE) technique with a clinical device, based on an ultrasound elastometry system called Fibroscan.
  
  
  METHODS
  Ten healthy subjects underwent an MRE and a Fibroscan test. The MRE technique used a round pneumatic driver at 60 Hz to generate shear waves inside the liver. An elastogram representing a map of the liver stiffness was generated allowing for the measurement of the average liver stiffness inside a region of interest. The Fibroscan technique used an ultrasound probe (3.5 MHz) composed of a vibrator that sent low-frequency (50 Hz) shear waves inside the right liver lobe. The probe acts as an emitter-receptor that measures the velocity of the waves propagated inside the liver tissue.
  
  
  RESULTS
  The mean shear stiffness measured with the MRE and Fibroscan techniques were 1.95+/-0.06 kPa and 1.79+/-0.30 kPa, respectively. A higher standard deviation was found for the same subject with Fibroscan.
  
  
  CONCLUSIONS
  This study shows why MRE should be investigated beyond the Fibroscan. The MRE technique provided elasticity of the entire liver, meanwhile the Fibroscan provided values of elasticity locally.
authors.affiliation: Biomechanics and Bioengineery Laboratory, UMR CNRS 6600, Université de Technologie de Compiègne, and Centre hospitalier de Compiègne, service gastro-entérologie et hépatologie, Compiègne, France. sabine.bensamoun@utc.fr
authors.forename: Sabine F
authors.initials: SF
authors.lastname: Bensamoun
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Ludovic
authors.initials: L
authors.lastname: Robert
authors.forename: Fabrice
authors.initials: F
authors.lastname: Charleux
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Latrive
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Ho Ba Tho
mesh_terms: D000328:Adult; D000465:Algorithms; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity