Regenerative liver nodules (RNs) are a form of non-neoplastic nodules that arise in a cirrhotic liver.
This may be slightly different from the term nodular regenerative hyperplasia, which are described histopathologically as regenerative nodules with little or no hepatic fibrosis and largely healthy hepatic architecture 1. When there is accumulation of iron in the nodules, they are called siderotic nodules.
RNs form in the setting of necrosis or RNs can be of three types 5:
- micronodules <3 mm
- macronodules >3 mm
- giant RNs > 5 cm (rare)
RNs appear as round, well-defined nodules (usually in the thousands) present throughout the liver with surrounding fibrosis 5.
On post-contrast CT and MRI RNs enhance similar to the normal liver parenchyma in both portal venous and hepatocellular/delayed phases, and thus may not be distinguishable in a cirrhotic liver. There is no arterial phase enhancement.
Regenerative nodules are rarely visible on non-contrast CT unless they are siderotic. Siderotic regenerative nodules (containing iron) are hyperdense to liver on precontrast imaging and become isodense to liver on post contrast phases.
CT arterial portography (CTAP)
Contrast injection into the superior mesenteric artery (after arterial vascular access). RNs are generally visualised as enhancing nodules surrounded by lower attenuation thin septa.
CT hepatic arteriography (CTHA)
Contrast injection into the common hepatic artery (after arterial vascular access). RNs are generally visualised as nonenhancing nodules surrounded by enhancing fibrous septa.
CTHA is considered more sensitive than the former in depicting regenerative nodules 4.
RNs are common in a cirrhotic liver:
- T1: variable
- T2: hypointense
- T2*: hypointense
They usually do not enhance, or enhance less than the liver parenchyma.
Treatment and prognosis
- 1. Gupta AA, Kim DC, Krinsky GA et-al. CT and MRI of cirrhosis and its mimics. AJR Am J Roentgenol. 2004;183 (6): 1595-601. AJR Am J Roentgenol (full text) - Pubmed citation
- 2. Xu H, Kong X, Xiong Y et-al. MR features of regenerative nodules and dysplastic nodules in the cirrhotic liver. J. Huazhong Univ. Sci. Technol. Med. Sci. 2005;25 (5): 601-3. - Pubmed citation
- 3. Lee JM, Choi BI. Hepatocellular nodules in liver cirrhosis: MR evaluation. Abdom Imaging. 2011;36 (3): 282-9. doi:10.1007/s00261-011-9692-2 - Pubmed citation
- 4. Lim JH, Kim EY, Lee WJ et-al. Regenerative nodules in liver cirrhosis: findings at CT during arterial portography and CT hepatic arteriography with histopathologic correlation. Radiology. 1999;210 (2): 451-8. Radiology (full text) - Pubmed citation
- 5. Hanna RF, Aguirre DA, Kased N et-al. Cirrhosis-associated hepatocellular nodules: correlation of histopathologic and MR imaging features. Radiographics. 2008;28 (3): 747-69. doi:10.1148/rg.283055108 - Pubmed citation
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|Regenerative hepatic nodules||✗|
|Hepatic nodular regeneration||✗|
|Hepatic regenerative nodules||✗|
|Regenerative liver nodules||✗|
|Regenerative hepatic nodule||✗|
|Regenerative nodules in liver||✗|