ARRS 2022 Abstracts


E1055. The Spectrum of Focal Lesions in the Cirrhotic Liver: Pearls and Pitfalls
  1. Anup Shetty; Mallinckrodt Institute of Radiology
  2. Alexander Reddy; Mallinckrodt Institute of Radiology
  3. Katharina Feister; Mallinckrodt Institute of Radiology
  4. Omar McCarty; Mallinckrodt Institute of Radiology
  5. Anup Bhattacharya; Mallinckrodt Institute of Radiology
  6. Daniel Ludwig; Mallinckrodt Institute of Radiology
  7. Tyler Fraum; Mallinckrodt Institute of Radiology
Liver MRI is frequently performed for surveillance or categorization of focal lesions in the cirrhotic patient. The Liver Imaging Reporting and Data System (LI-RADS) provides the contextual framework from which to approach focal liver lesions in the cirrhotic patient. Crucially, common benign liver lesions, such as focal nodular hyperplasia and hepatic adenoma, are uncommon in patients with cirrhosis, whereas other lesions such as arterioportal shunts and confluent hepatic fibrosis, are more common. Accurate categorization of focal lesions in the cirrhotic liver by the radiologist is critical in appropriately directing patient management and preventing the need for biopsy of lesions that can be confidently diagnosed as HCC on imaging. The purpose of the exhibit is to illustrate the range of lesions encountered in the cirrhotic patient and their interpretation using the framework of LI-RADS with a case-based format.

Educational Goals / Teaching Points
This exhibit will discuss fundamental concepts within LI-RADS as well as nuances that aid in proper interpretation. The target population in whom LI-RADS should be applied for interpretation will be discussed. Common benign liver lesions such as hemangiomas, cysts, arterioportal shunts, and focal fat will be illustrated. Uncommon benign liver lesions such as siderotic nodules, peribiliary cysts, confluent hepatic fibrosis, and FNH-like lesions will be reviewed. The gamut of suspicious lesions ranging from LI-RADS 3 to LI-RADS 5 will be reviewed. An indepth discussion of LI-RADS M and targetoid lesions in the cirrhotic liver will be pursued, exploring the differential diagnosis of HCC, cholangiocarcinoma, combined (biphenotypic) hepatocellular-cholangiocarcinoma, and uncommon benign etiologies. The key concept of tumor-in-vein and how to appropriately diagnose and characterize it will be appraised. Ancillary features and how to appropriately and efficiently utilize them will be highlighted, including diffusion restriction, intermediate T2 hyperintensity, fat and iron content, and other features. Finally, pitfalls in interpretation such as arterial phase timing and special considerations if imaging with Eovist will be reviewed, providing in sum a comprehensive guide to how to approach the focal liver lesion in the cirrhotic patient.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The imaging techniques and standards of LI-RADS will be reviewed. Strategies for achieving appropriate late hepatic arterial phase timing, including fixed bolus timing, a test bolus, bolus tracking, and multi-arterial phase acquisition will be compared and illustrated. Practical consideration of the benefits and drawbacks of using Eovist in imaging the cirrhotic liver will be discussed.

A broad variety of liver lesions may be encountered in the cirrhotic patient. A structured framework for analysis, an understanding of key technical parameters that may hinder or aid in diagnosis and a knowledge of the range of disease processes that can occur will aid the radiologist in confident and accurate interpretation, providing maximal diagnostic value and minimizing the need for unnecessary biopsy.