title: Noninvasive assessment of liver fibrosis using ultrasound-based shear wave measurement and comparison to magnetic resonance elastography.
abstract: OBJECTIVE
  Magnetic resonance elastography (MRE) has excellent performance in detecting liver fibrosis and is becoming an alternative to liver biopsy in clinical practice. Ultrasound techniques based on measuring the propagation speed of the shear waves induced by acoustic radiation force also have shown promising results for liver fibrosis staging. The objective of this study was to compare ultrasound-based shear wave measurement to MRE.
  
  
  METHODS
  In this study, 50 patients (28 female and 22 male; age range, 19-81 years) undergoing liver MRE examinations were studied with an ultrasound scanner modified with shear wave measurement functionality. For each patient, 27 shear wave speed measurements were obtained at various locations in the liver parenchyma away from major vessels. The median shear wave speed from all measurements was used to calculate a representative shear modulus (μ) for each patient. Magnetic resonance elastographic data processing was done by a single analyst blinded to the ultrasound measurement results.
  
  
  RESULTS
  Ultrasound and MRE measurements were correlated (r = 0.86; P < .001). Receiver operating characteristic (ROC) analysis was applied to the ultrasound measurement results with the MRE diagnosis as the "ground truth." The area under the ROC curve for separating patients with minimum fibrosis (defined as μ(MRE) ≤2.9 kPa) was 0.89 (95% confidence interval, 0.77-0.95), and the area under the ROC curve for separating patients with advanced fibrosis (defined as μ(MRE) ≥5.0 kPa) was 0.96 (95% confidence interval, 0.87-0.99).
  
  
  CONCLUSIONS
  Results indicate that the ultrasound-based shear wave measurement correlates with MRE and is a promising method for liver fibrosis staging.
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Heng
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Duane D
authors.initials: DD
authors.lastname: Meixner
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Hua
authors.initials: H
authors.lastname: Xie
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Vijay
authors.initials: V
authors.lastname: Shamdasani
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Shiwei
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Robert
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Urban
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: William
authors.initials: W
authors.lastname: Sanchez
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Callstrom
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: Richard L
authors.initials: RL
authors.lastname: Ehman
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.).
authors.forename: James F
authors.initials: JF
authors.lastname: Greenleaf
authors.affiliation: Departments of Physiology and Biomedical Engineering (H.Z., M.W.U., J.F.G., S.C.), Radiology (J.C., D.D.M., M.R.C., R.L.E.), and Gastroenterology and Hepatology (W.S.), Mayo Clinic College of Medicine, Rochester, Minnesota USA; Philips Research North America, Briarcliff Manor, New York USA (H.X., S.Z., J.-L.R.); and Philips Healthcare, Bothell, Washington USA (V.S.). chen.shigao@mayo.edu.
authors.forename: Shigao
authors.initials: S
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D015203:Reproducibility of Results; D055815:Young Adult
keywords: gastrointestinal ultrasound; liver fibrosis; magnetic resonance elastography; shear wave; ultrasound