Update on the role of elastography in liver disease

Abstract

The diagnosis of liver fibrosis and the assessment of its severity are important to provide appropriate management, to determine the prognosis or the need for surveillance. Currently, for fibrosis staging, liver stiffness measurement (LSM) with the shear wave elastography (SWE) techniques is considered a reliable substitute for liver biopsy in several clinical scenarios. Nonetheless, it should be emphasized that stiffness value is a biomarker of diffuse liver disease that must be interpreted taking into consideration anamnesis, clinical and laboratory data. In patients with diffuse liver disease, it is more clinically relevant to determine the likelihood of advanced disease rather than to obtain an exact stage of liver fibrosis using a histologic classification. In this regard, a ‘rule of five’ for LSMs with vibration-controlled transient elastography (VCTE) and a ‘rule of four’ for LSMs with the acoustic radiation force impulse (ARFI)-based techniques have been proposed. In patients with advanced chronic liver disease (CLD), the risk of liver decompensation increases with increasing liver stiffness value. SWE has been proposed as a tool to predict the risk of death or complications in patients with CLD. LSM by VCTE combined with platelets count is a validated non-invasive method for varices screening, with very good results in terms of invasive procedures being spared. ARFI-based techniques also show some promising results in this setting. LSM, alone or combined in scores or algorithms with other parameters, is used to evaluate the risk of hepatocellular carcinoma occurrence. Due to the high prevalence of CLD, screening the population at risk is of interest but further studies are needed.

Determination and prospective validation of cut-off values for the diagnosis of liver cirrhosis for point shear-wave elastography/acoustic radiation force impulse imaging using the ACUSON Sequoia ultrasound system

“…In a recent prospective study by Yoo et al [22] assessing interobserver-variability of SWE measurements in 53 patients with chronic liver disease, the authors found an excellent inter-and intra-observer agreement. Similar results can be found in the literature in studies in patients with chronic liver disease as well as in both elasticity phantoms and healthy individuals [23][24][25][26].…”

Accuracy and concordance of two-dimensional shear-wave elastography using transient elastography as the reference in chronic viral hepatitis and HIV infection in Rio de Janeiro, Brazil

“…Agreement between transient elastography and 2D-SWE might be poor in HIV mono-infected people due to the presence of confounding factors, such as steatosis or hepatic necro-inflammatory activity associated with a low prevalence of fibrosis, known as spectrum bias [15]. The impact of the spectrum bias and potential confounding factors in staging liver fibrosis by non-invasive methods was previously reported [21,27]. Additionally, metabolic features or liver steatosis are highly frequent in people living with HIV mono-infection under antiretroviral therapy [28].…”

Ultrasonic surface acoustic wave elastography: A review of basic theories, technical developments, and medical applications

“…2 It is also used in treatment monitoring 3 as well as image-guided therapy. 4 By evaluating tissue elasticity, elastography techniques enable the diagnosis of lung diseases like pulmonary fibrosis, 5,6 pulmonary edema, 7 and emphysema, 8 as well as liver conditions such as fibrosis, 9 cirrhosis, 10 and hepatic tumors. 11 In renal disease, elastography aids in the early detection of subclinical renal fibrosis, 12 a major risk factor for chronic kidney disease, offering a valuable tool for preventive intervention.…”