The Use of Two-Dimensional Shear Wave Elastography in People with Obesity for the Assessment of Liver Fibrosis in Non-Alcoholic Fatty Liver Disease

Abstract

Obesity is associated with significant comorbidities, including non-alcoholic fatty liver disease (NAFLD). Given its potential to progress to advanced liver disease, monitoring the extent and progress of liver fibrosis and assessing its fibrosis stage are essential. Although liver biopsy is considered to be the gold standard for liver fibrosis staging, it is an invasive procedure with risk of complications. Considering the rising prevalence of obesity and NAFLD globally, developing non-invasive diagnostic methods is a priority. Transient elastography (TE) is increasingly being used to assess the severity of liver disease. However, in the presence of severe obesity, the increased thickness of subcutaneous adipose tissue and changes in anatomy may affect its diagnostic accuracy. Two-dimensional shear wave elastography (2D-SWE) assesses the liver stiffness in real time along with simultaneous anatomic B-mode ultrasound imaging and allows selection of the region of interest. This would suggest that 2D-SWE has several advantages over TE in patients with severe obesity. The purpose of this review is to examine the current literature addressing the use of 2D-SWE in the assessment of liver fibrosis in patients with NAFLD. This review also examines the evidence on the use of 2D-SWE in patients with obesity and NAFLD and compares it to TE as a novel and non-invasive method of assessing liver fibrosis.

Ultrasonographic index for the diagnosis of non-alcoholic steatohepatitis in patients with non-alcoholic fatty liver disease

“…MR elastography has the advantages of a larger sampling volume and less technical failure, but US elastography has been more widely used in clinical practice because of its convenience, shorter acquisition time, lower cost, and higher availability. US-based SWE can be divided into TE, 2D-SWE, and p-SWE (24,25). TE is the first commercially available US-based elastography technique for the measurement of liver stiffness with one-dimensional probe (25).…”

“…US-based SWE can be divided into TE, 2D-SWE, and p-SWE (24,25). TE is the first commercially available US-based elastography technique for the measurement of liver stiffness with one-dimensional probe (25). It has demonstrated excellent diagnostic performance for detecting advanced fibrosis and cirrhosis in NAFLD patients (26,27).…”

“…It has demonstrated excellent diagnostic performance for detecting advanced fibrosis and cirrhosis in NAFLD patients (26,27). 2D-SWE and p-SWE are more recently developed US-based elastography and incorporated into conventional gray-scale US, allowing real-time measurement of liver stiffness (25). 2D-SWE also has shown good diagnostic performance for the diagnosis of various fibrosis stages in NAFLD patients (28,29).…”

Ultrasound Elastography—Cornerstone of Non-Invasive Metabolic Dysfunction-Associated Fatty Liver Disease Assessment

“…Finally, aforementioned factors affecting the final results have not yet been fully reported for many of the latest equipment, as opposed to the methods available for more than five years [ 10 ]. However, a study on phantoms recently showed that there is a significant difference in LSM estimates among systems, but no statistically significant differences were found among observers using the same system, and they also reported very good agreement between systems [ 11 ]. Due to the high dependency of the proposed cut off values on the specific elastographic technique, it is important to notice that the following is a revision of mainly TE derived cut off indices.…”

“…A two-step strategy using TE followed by 2D-SWE was reported to be even more accurate in cACLD detection. Multi-step strategies using 2D-SWE may also significantly reduce the need for liver biopsy [ 6 , 11 ]. Individual authors cite a significantly extended measurement time as a disadvantage of such evaluation [ 11 ].…”