Technical ReportSurveillance liver MRI for monitoring patients with known or suspected chronic liver disease
Introduction
Chronic liver disease (CLD) affects 3 million people in the United States.1 The leading causes of CLD are hepatitis C (HCV) and B (HBV) viruses, alcohol abuse and, in western countries, non-alcoholic fatty liver disease (NAFLD). Less common risk factors include immune-mediated liver disease, such as autoimmune hepatitis, sclerosing cholangitis, and primary biliary cirrhosis; genetic-related liver disease, such as hereditary haemochromatosis; and toxins (e.g., iron overload). The morphological and functional changes seen with CLD, ranging from steatosis to fibrosis and, ultimately, cirrhosis, are due to a failed wound-healing process in response to these inciting factors. CLD is a dynamic, reversible process up to a point, beyond which fibrosis becomes irreversible.2
Patients with risk factors for CLD require monitoring for early detection and staging, for assessment of disease progression rate, and for early diagnosis of hepatocellular carcinoma (HCC).3 The presence of CLD must be evaluated prior to liver transplantation in both the donor and recipient, as its presence influences the outcome for both individuals. Further, select patients may be monitored for inciting factors of CLD, such as monitoring hepatic fat infiltration in patients undergoing bariatric procedures and surveillance for iron overload in patients undergoing repeated blood transfusions. Response to therapy for CLD should also be monitored, given the high costs and the side effects of treatment.4
Liver biopsy represents the reference standard for evaluation of CLD; however, it has several limitations. It is an invasive procedure with serious complications occurring in about 1.1% of cases.5 Bleeding is the most frequent complication and increases in patients with a low platelet count, a common feature of CLD. Liver biopsy requires patient cooperation (e.g., breath hold) and may be limited in the paediatric population. Further, samples obtained by biopsy may not fully capture the overall stage of disease, as the liver is heterogeneously affected by CLD and different stages in the continuum from normal to cirrhotic may be present simultaneously.6
Given the limitations of biopsy, imaging plays an important role in the surveillance of patients with risk factors for CLD.4 The challenge for imaging is detecting the earliest changes of CLD, such as early fat infiltration, iron overload, and progressive stiffness increase. New ultrasonography (US) techniques, such as sonoelastography and contrast-enhanced US, have been introduced to quantify fibrosis, with promising results.7 Although these US techniques are low in cost, they are limited by acoustic window, operator-dependence, and particularly important in this patient population, body habitus. Moreover, US does not provide fat and iron quantification. Radiation dose and high cost limit the use of new computed tomography (CT) tools, such as dual-energy CT.8 With the introduction of new magnetic resonance imaging (MRI) sequences that can provide fat and iron quantification, as well as assessment of fibrosis, MRI, without radiation dose or significant operator dependence, is poised as the ideal means for accurate, reproducible monitoring of patients with CLD.9, 10
Section snippets
Technique
Recent advances in MRI sequences have made MRI well suited for assessment and quantification of the early markers most frequently associated with CLD: hepatic fat infiltration, iron overload, and stiffness (or fibrosis). At Johns Hopkins Medical Institution, a new unenhanced surveillance liver MRI protocol has been implemented, which is performed separate from the more traditional, comprehensive, contrast-enhanced liver protocols. The goal of the surveillance protocol is fast, low-cost, and
Discussion
Although liver biopsy may be the reference standard for the diagnosis of CLD, as a non-invasive technique, MRI has an important role to play in surveillance. Additionally, MRI is particularly well suited for capturing the heterogeneity of CLD. Early detection of CLD represents the primary challenge for imaging, and in the last few years several MRI sequences have been developed to quickly and accurately assess fat infiltration, iron overload, and fibrosis, which occur in the early stages of
References (24)
- et al.
Liver cirrhosis
Lancet
(2014) - et al.
Complication rate of percutaneous liver biopsies among persons with advanced chronic liver disease in the HALT-C trial
Clin Gastroenterol Hepatol
(2010) - et al.
Sampling variability of liver fibrosis in chronic hepatitis C
Hepatology (Baltimore, Md.)
(2003) - et al.
MR imaging of diffuse liver disease: from technique to diagnosis
Radiol Clin North Am
(2014) - et al.
R2* magnetic resonance imaging of the liver in patients with Iron Overload
Blood
(2009) - et al.
MRI R2 and R2* mapping accurately estimates hepatic iron concentration in transfusion-dependent thalassemia and sickle cell disease patients
Blood
(2005) - et al.
Direct T2 quantification of myocardial edema in acute ischemic injury
JACC Cardiovasc Imaging
(2011) - et al.
The use of T2+-weighted multi-echo GRE imaging as a novel method to diagnose hepatocellular carcinoma compared with gadolinium-enhanced MRI: a feasibility study
Magn Reson Imaging
(2010) Digestive Diseases Statistics for the United States
(2015)- et al.
Pathobiology of liver fibrosis: a translational success story
Gut
(2015)
The current economic burden of cirrhosis
Gastroenterol Hepatol
CEUS and Fibroscan in non-alcoholic fatty liver disease and non-alcoholic steatohepatitis
World J Hepatol
Cited by (4)
Evaluation of liver fibrosis and cirrhosis on the basis of quantitative T1 mapping: Are acute inflammation, age and liver volume confounding factors?
2021, European Journal of RadiologyCitation Excerpt :Despite the unquestionable advantages, the limitations of US-elastography are unreliability in obese patients and considerable user-dependency [11]. MRE is considered as a robust non-invasive method for the determination of liver fibrosis or cirrhosis even in early stages and is providing a high diagnostic accuracy [9,12]. The disadvantages of MRE are high sensitivity for iron overload [13], its examination time, and high costs [14].
Acute Pancreatitis: How Can MR Imaging Help
2018, Magnetic Resonance Imaging Clinics of North AmericaCitation Excerpt :Magnetic resonance elastography (MRE) is an MR imaging technique that evaluates the stiffness of tissues in vivo. Continuous mechanical waves at a low frequency (40–60 Hz) are propagated from an acoustic driver to a passive driver on a patient’s body, resulting in periodic tissue displacement.39,40 The frequency and character of the propagated waves provide information about the target tissues stiffness.
Current imaging techniques for noninvasive staging of hepatic fibrosis
2019, American Journal of Roentgenology