Synopsis

MRI in the cirrhotic liver has important roles in the standard care of cirrhotic patients. Recent advance in MRI also offers functional information which can serve as MR-based biomarker to predict patients’ outcome.

Target audience

Highlights

• The purpose of imaging in the cirrhotic liver is to find HCCs at early stage and evaluate liver fibrosis/complications of cirrhosis.
• Minimum requirements for liver MRI include non-contrast T2WI, DWI, and in/opposed phase T1WI for detection/characterization of the nodules and contrast-enhanced MRI to assess hypervascularity and wash-out.
• Advanced technique of liver MRI includes MR elastography and hepatobiliary contrast agents, which can serve as MR-based biomarker of the cirrhotic patients.

Objectives

Minimal requirements of MRI in the cirrhotic liver

• T2WI is used for characterization of the liver nodule. Very bright signal on T2WI suggest benignity; cyst and hemangioma, and mild hyper-intensity suggests malignancy.
• Chemical shift MRI (in and opposed phase T1WI) is necessary to detect fat degeneration of the nodule. If observed, it suggest HCC rather than benign/pre-malignant nodules.
• DWI is needed to detect small liver lesions including intrahepatic metastasis of HCCs. DWI is also useful to distinguish high grade from low grade HCCs by the intensity/ADCs ¹⁾.
• Dynamic contrast-enhanced MRI is mandatory to characterize liver lesions. Wash-in and wash-out is the key. Hypervascularity should be carefully assessed compared with pre-contrast image.

Advanced techniques of MRI in the cirrhotic liver

• Fibrosis can be measured with MR elastography (MRE), which is now available in the clinic ²⁾. Recent studies suggest that liver stiffness with MRE can be useful to predict patients’ outcome in many ways.
• Hepatobiliary contrast agent provides more information than conventional gadolinium-based contrast agents for the non-hypervascular liver nodule (nodules of non-hypervascularity and low signal intensity in hepatobiliary phase [NLH]),³⁾ which is pathologically early-HCC ⁴⁾ and a strong risk factor of HCC development in the future ⁵⁾.

Conclusion

Acknowledgements

References

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