Application of Ultrasound Liver Elastography to the Diagnosis and Monitoring of Liver Disease

摘要

It is clinically important to assess the degree of hepatic injury in addition to the clinical diagnosis of underlying liver diseases. Fibrotic deposits represent the response of liver tissue to damage, and the degree of hepatic fibrosis is an important prognostic indicator and therapeutic target in liver diseases. Invasive liver biopsy has been the golden standard for the assessment of the degree of hepatic fibrosis with hazard. Non-invasive assessments have been widely used to assess the degree of hepatic fibrosis instead of liver biopsy. Ultrasound elastography has been the recent interest for the clinical assessment of hepatic fibrosis. Ultrasound elastography technology involves the use of a machinery to generate shear waves in the vicinity of hepatic tissue and then the monitoring the propagation of the shear waves. A mild external force can also be applied to the liver tissue for the monitoring of degree of strain. Then ultrasound devices can calculate the speed of the shear waves and the degree of strain, and convert these data into ultrasound images to determine the elasticity of the liver tissue. Current elastography determining shear wave speed include Transient Elastography (TE), Acoustic Radiation Force Imaging (ARFI), Point Shearwave Elastography (SWE), and Two-dimensional SWE12 Figure 1.