Liver Fibrosis, Fat, and Iron Evaluation with MRI and Fibrosis and Fat Evaluation with US: A Practical Guide for Radiologists

by Selleckchem | Aug 02 2023

Quantitative imaging biomarkers of liver disease measured by using MRI and US are emerging as important clinical tools in the management of patients with chronic liver disease (CLD). Because of their high accuracy and noninvasive nature, in many cases, these techniques have replaced liver biopsy for the diagnosis, quantitative staging, and treatment monitoring of patients with CLD. The most commonly evaluated imaging biomarkers are surrogates for liver fibrosis, fat, and iron. MR elastography is now routinely performed to evaluate for liver fibrosis and typically combined with MRI-based liver fat and iron quantification to exclude or grade hepatic steatosis and iron overload, respectively. US elastography is also widely performed to evaluate for liver fibrosis and has the advantage of lower equipment cost and greater availability compared with those of MRI. Emerging US fat quantification methods can be performed along with US elastography. The author group, consisting of members of the Society of Abdominal Radiology (SAR) Liver Fibrosis Disease-Focused Panel (DFP), the SAR Hepatic Iron Overload DFP, and the European Society of Radiology, review the basics of liver fibrosis, fat, and iron quantification with MRI and liver fibrosis and fat quantification with US. The authors cover technical requirements, typical case display, quality control and proper measurement technique and case interpretation guidelines, pitfalls, and confounding factors. The authors aim to provide a practical guide for radiologists interpreting these examinations.

Comments:

Quantitative imaging biomarkers of liver disease measured using MRI and US have become essential tools in the clinical management of patients with chronic liver disease (CLD). These techniques offer high accuracy and noninvasiveness, often replacing the need for liver biopsy in diagnosing, staging, and monitoring CLD. The most commonly evaluated imaging biomarkers are indicators of liver fibrosis, fat accumulation, and iron overload.

MR elastography (MRE) is routinely used to assess liver fibrosis and is often combined with MRI-based measurements of liver fat and iron to evaluate hepatic steatosis (fat accumulation) and iron overload, respectively. US elastography is also widely used for liver fibrosis assessment and has the advantage of being more cost-effective and widely available compared to MRI. Additionally, emerging US methods can quantify liver fat alongside elastography.

The author group, comprised of members from the Society of Abdominal Radiology (SAR) Liver Fibrosis Disease-Focused Panel (DFP), SAR Hepatic Iron Overload DFP, and the European Society of Radiology, has provided a comprehensive review of liver fibrosis, fat, and iron quantification using MRI, as well as liver fibrosis and fat quantification using US. The review covers technical requirements, typical case displays, quality control, proper measurement techniques, case interpretation guidelines, pitfalls, and confounding factors. The authors' objective is to offer a practical guide for radiologists involved in interpreting these imaging examinations.