Ultrasound Elastography for Liver Disease with Focus on Hepatic Fibrosis

Abstract

Chronic liver disease is a worldwide problem, including in Korea, and its major consequence is an increasing deposition of fibrous tissue within the liver, leading to cirrhosis and finally hepatocellular carcinoma. The diagnosis and staging of liver fibrosis are important to prioritize for treatment and determine the prognosis with the potential for reversibility. Previously, the only method for diagnosing and staging of fibrosis was a liver biopsy. However, due to the limitations of liver biopsy, the recent development of ultrasound elastography (USE) techniques allows a non-invasive method of diagnosis and staging for liver fibrosis. USE enables non-invasive measurement of tissue mechanical properties through observation of shear-wave propagation in the tissue of interest. Transient elastography (TE) is a non-imaging elastographic technique that is the most popular and extensively validated method, while point shear wave elastography (p-SWE) and two-dimensional shear wave elastography (2D-SWE) combine imaging with elastography. The evidence suggests that p-SWE is as accurate as but more reliable than TE, while 2D-SWE is more accurate than TE. The author reviews the background of chronic liver disease, the types of USE, methods of examination, and interpretation of the results.