Hepatic siderotic nodules are a type of regenerative nodule formed in a cirrhotic liver. They occur in hepatic hemosiderosis. The nodules have an increased iron content compared with other regenerative nodules. They may be non-dysplastic or dysplastic.
The reason why these nodules concentrate iron is uncertain, but it is attributed to differential iron metabolism in the nodule's cell population from differential transferrin expression 3. Stainable iron occurs in approximately 25% of all regenerative nodules 3. Of note, some prefer the term "iron-rich" nodule since the term "siderotic" may have a different meaning in pathology.
- nodules are potentially hyperattenuating, but the amount of hyperattenuation may be slight, and the finding is non-specific
- moderate to marked T2/T2* hypointensity due to the T2 shortening effect of iron
- may be T1 hypo-, iso-, or hyperintense
- increased hypointensity on the second echo of an in- and out-of-phase sequence
Imaging cannot reliably differentiate between non-dysplastic or dysplastic siderotic nodules. A siderotic nodule's risk for hepatocellular carcinoma can be classified using LI-RADS. A "probably benign" siderotic nodule fulfills the criteria for an LR2 cirrhosis-associated nodule.
- 1. Roth CG. Fundamentals of Body MRI: Expert Consult- Online and Print, 1e. Saunders. ISBN:141605183X. Read it at Google Books - Find it at Amazon
- 2. Mitchell DG, Bruix J, Sherman M et-al. LI-RADS (Liver Imaging Reporting and Data System): Summary, discussion, consensus of the LI-RADS Management Working Group and future directions. Hepatology. 2014; . doi:10.1002/hep.27304 - Pubmed citation
- 3. Terada T, Nakanuma Y. Survey of iron-accumulative macroregenerative nodules in cirrhotic livers. Hepatology. 1989;10 (5): 851-4. Pubmed citation