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Acoustic Radiation Force Impulse (ARFI) Elastography for Detecting Hepatic Fibrosis in Patients with Hepatitis C

April 25, 2019

Health Problem: Approximately 3.2 million people in the United States have a chronic hepatitis C virus (HCV) infection, which puts them at risk for developing hepatic fibrosis or cirrhosis, a need for liver transplantation, and possible death due to liver failure or liver cancer. However, HCV infection is a treatable disease and effective antiviral treatments that can lead to undetectable levels of the virus are available. An accurate test to detect the early stages of an HCV infection-related complication, such as hepatic fibrosis, may lead to earlier treatment.

Technology Description: Acoustic radiation force impulse (ARFI) elastography, also referred to as shear wave elastography, is a noninvasive alternative or adjunct to liver biopsy and involves the analysis of ultrasonographic wave propagation and tissue deformation in patients suspected of having or known to have chronic liver disease. ARFI is based on the principle that fibrosis changes the elasticity and viscosity of tissue. By assessing the propagation of acoustic waves through the liver, which travel faster through fibrotic tissue, the presence and extent of fibrosis can be measured. The ultrasonographic system used for ARFI enables imaging of the liver so that each region of interest can be placed in a site with no major blood vessels or other structures that could interfere with shear wave detection. This test can be performed in an ambulatory setting or at the bedside.

Controversy: ARFI elastography is a physical method that may not be feasible or may have poor accuracy in patients who have conditions that interfere with ultrasonography, such as obesity, ascites, or narrow spaces between ribs.

Key Questions: For the evaluation and management of adult patients with chronic HCV infection with known or suspected hepatic fibrosis:

  • What is the accuracy of ARFI elastography relative to a reference standard of liver biopsy and histopathology for detecting and staging hepatic fibrosis?
  • What is the accuracy of ARFI elastography compared with other technologies for detecting and staging hepatic fibrosis or for determining prognosis?
  • Does the information provided by ARFI elastography improve treatment decisions and health outcomes?
  • Is ARFI elastography associated with any safety issues?
  • Have definitive patient selection criteria been established for the use of ARFI elastography in detecting and staging hepatic fibrosis?