title: Non-invasive evaluation of liver fibrosis using acoustic radiation force impulse imaging in chronic hepatitis patients with hepatitis C virus infection.
abstract: OBJECTIVE
  Acoustic radiation force impulse (ARFI) imaging is a new technology for performing liver elastography. However, use of this technique to estimate the degree of fibrosis in chronic liver disease (CLD) related to hepatitis C virus (HCV) infection has not yet been established. We evaluated the validity, accuracy and flexibility of the ARFI method in CLD.
  
  
  METHODS
  Subjects comprised 30 patients with chronic hepatitis (CH), 30 patients with liver cirrhosis (LC) and 10 healthy subjects (controls). All patients had HCV infection. Elastography of the liver was performed at different sites using the ARFI method. Relationships between shear wave velocity (SWV) obtained by ARFI, clinical diagnosis, serum parameters of liver function and fibrosis in the liver were evaluated. Moreover, cut-off values for differential diagnosis between CH and LC were estimated using area under the receiver operating characteristics (AUROC).
  
  
  RESULTS
  Mean SWV (+/- standard deviation) was 2.67 +/- 1.18 m/s, 1.33 +/- 0.54 m/s and 0.99 +/- 0.21 m/s in the LC, CH and control groups, respectively. SWV was significantly higher in the LC group than in the CH and control groups (p < 0.0001), and in the CH group than in the control group (p = 0.0023). SWV in each stage of fibrosis was 1.09 +/- 0.22 m/s in F0-1, 1.24 +/- 0.52 m/s in F2, 1.61 +/- 0.79 m/s in F3, and 2.35 +/- 1.11 m/s in F4. SWV correlated significantly with serum total bilirubin, alanine aminotransferase, cholesterol, albumin, platelet counts, prothrombin time, fibrosis markers, hyaluronic acid and type IV collagen. A steady stepwise increase in elasticity correlated significantly with severity of hepatic fibrosis (p = 0.9772; p = 0.002). Diagnostic ability for LC was superior in ARFI (AUROC, 0.930 in ARFI; 0.846 in aspartate aminotransferase to platelet ratio index; 0.829 in Forns' index; and 0.785 in platelet count).
  
  
  CONCLUSIONS
  ARFI is extremely useful for distinguishing between CH and LC, and SWV might correlate significantly with degree of progression in CLD with HCV infection.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Internal Medicine, Iwate Medical University School of Medicine, Uchimaru 19-1, Morioka, Iwate 020-8505, Japan. hikuro@iwate-med.ac.jp
authors.forename: Hidekatsu
authors.initials: H
authors.lastname: Kuroda
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kakisaka
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Tatemichi
authors.forename: Kei
authors.initials: K
authors.lastname: Sawara
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Kanta
authors.initials: K
authors.lastname: Oikawa
authors.forename: Akio
authors.initials: A
authors.lastname: Miyasaka
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Takikawa
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Masuda
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Suzuki
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D019698:Hepatitis C, Chronic / Q000175:diagnosis*; D006801:Humans; D008099:Liver / Q000503:physiopathology; D008103:Liver Cirrhosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve