Ultrasound elastography in liver

Abstract

Conventional imaging techniques cannot provide information about tissue mechanical properties. Many injuries can cause changes in tissue stiffness, especially tumors and fibrosis. In recent years, various non-invasive ultrasound methods have been developed to study tissue elasticity for a large number of applications (breast, thyroid, prostate, kidneys, blood vessels, liver…). For non-invasive assessment of liver diseases, several ultrasound elastography techniques have been investigated: Transient elastography (the most extensively used), Real Time Elastography (RTE), Acoustic Radiation Force Impulse Imaging (ARFI) and more recently Shear Wave Elastography (SWE). Even if evaluation of liver fibrosis in chronic liver disease remains the principal application, there are many others applications for liver: predicting cirrhosis-related complications; monitoring antiviral treatments in chronic viral liver disease; characterizing liver tumors; monitoring local treatments, etc. The aim of this article is to report on the different hepatic ultrasound elastography techniques, their advantages and disadvantages, their diagnostic accuracy, their applications in clinical practice.

Shear wave elastography of placenta: in vivo quantitation of placental elasticity in preeclampsia

“…SWE revealed that malignant tissues of breast lesions have higher stiffness due to the increase in the number of malignant cells and surrounding desmoplas- tic reactions (8). Several studies have evaluated noninvasive elastographic techniques for assessing liver fibrosis, which may decrease the need for liver biopsy (9). Other organ systems such as the hormone secretion system and the musculoskeletal system (10) have also been investigated.…”

Kidney Ultrasound Elastography: Review

“…But there are also some limitations, such as obesity, does not have capability to present data in ascites mediums and in focal lesion. The main limitation about liver is the non capability of measurement in left lobe 22,23,[28][29][30][31][32] .…”

Predictors of Liver Disease Severity in Children with Chronic Hepatitis B

“…Two main types of these methods are used: Analysis of serum biomarkers combinations (e.g., FibroTest) and novel imaging techniques that measure liver stiffness (elasticity), which is reduced in the presence of fibrosis. Elastography techniques include: Transient elastography (FibroScan, which analyzes liver stiffness by measuring the velocity of elastic shear waves generated by a mechanical impulse), Acoustic Radiation Force Impulse imaging (ARFI, method for quantifying mechanical properties of liver tissue by measuring the shear wave velocity which is induced by acoustic radiation), and Shear Wave Elastography (SWE, quantitative real-time assessment, based on the generation of a radiation force in the tissue in order to create the shear wave) [28,29]. Another method is Magnetic Resonance Elastography, which is expensive and, therefore, has not been used for clinical purposes yet.…”