regenerative nodules in liver

Contrast-enhanced
ultrasound of a regenerative nodule in the liver.
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Multiple
regenerative liver nodules uncovering a constrictive pericarditis. T1 out-of-phase, showing a 4 cm-nodule at segment III, slightly hyperintense.
www.eurorad.org • CC by-nc-sa-4.0
Multiple
regenerative liver nodules uncovering a constrictive pericarditis. A solid nodule at segment III is shown, almost isoechogenic to the remaining hepatic parenchyma. Several similar nodules were also found.
www.eurorad.org • CC by-nc-sa-4.0
Multiple
regenerative liver nodules uncovering a constrictive pericarditis. T1 out-of-phase, showing a smaller nodule at segment IVa, with similar features to the one in Fig. 4a.
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Multiple
regenerative liver nodules uncovering a constrictive pericarditis. The nodule in segment III is isointense on T2 without fat suppression.
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Multiple
regenerative liver nodules uncovering a constrictive pericarditis. The nodule in segment III is isointense on T2 SPAIR.
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Multiple
regenerative liver nodules uncovering a constrictive pericarditis. The nodule in segment IVa is isointense on T2 SPAIR.
www.eurorad.org • CC by-nc-sa-4.0
Multiple
regenerative liver nodules uncovering a constrictive pericarditis. The nodule at segment III is isointense on T1 GRE fat sat (THRIVE) without contrast.
www.eurorad.org • CC by-nc-sa-4.0
Multiple
regenerative liver nodules uncovering a constrictive pericarditis. The nodule in segment III is isointense on T1 GRE fat sat (THRIVE), hepatobiliary phase.
www.eurorad.org • CC by-nc-sa-4.0
Multiple
regenerative liver nodules uncovering a constrictive pericarditis. T1 GRE fat sat (THRIVE) after Gd EOB-DTPA, arterial phase, depicting mottled pattern of enhancement of the liver parenchyma and periportal hypointensity in keeping with perivascular lymphoedema.
www.eurorad.org • CC by-nc-sa-4.0
Qualitative
analysis of small (≤2 cm) regenerative nodules, dysplastic nodules and well-differentiated HCCs with gadoxetic acid MRI. MR scans in a patient with chronic hepatitis, HCV related, and a regenerative nodule in liver segment VIII. a-b T1 - and T2-weighted images do not reveal any focal liver lesion. c T1-weighted gradient-echo shows a hypervascular lesion without wash-out during the late dynamic phase d). On the corresponding MR image obtained during the liver-specific hepatobiliary phase (e), the lesion is isointense to adjacent hepatic parenchyma. At pathologic examination of the explanted liver, this lesion corresponded to a multiacinar cirrhotic nodule
bmcmedimaging.biomedcentral.com • CC-by-4.0
A small
hepatic nodule ( ≤2 cm) in cirrhotic liver: doTriphasic MRI and Diffusion-weighted image help in diagnosis. A male patient aged 63 years old presented with tender abdomen who underwent ultrasonography and revealed several small nodules and referred to the MRI unit for further evaluation. a An axial unenhanced T1WI shows multiple nodules of isointense signal similar to liver parenchyma. b An axial T2WI shows the lesion to be of low SI. c An axial post-contrast arterial phase image shows the lesion to be isointense. d, e An axial portal and delayed post-contrast image shows the lesions were also isointense with no contrast uptake. f DWI shows the lesions were isointense owing to free diffusion. Suggested MRI diagnosis: multiple regeneration nodules. Biopsy results: confirmed regeneration nodules
ejrnm.springeropen.com • CC-by-4.0
MR imaging in
liver cirrhosis: classical and new approaches. Fibrosis and regenerative nodules. Transverse STIR image shows a reticular pattern of the fibrotic bands surrounding hypointense regenerative nodules
insightsimaging.springeropen.com • CC-by-2.0
MR imaging in
liver cirrhosis: classical and new approaches. Non-tumoral nodules. Transverse opposed (a) and in-phase (b) T1W images show hyperintense nodules without decreased signal intensity on opposed-phase imaging and hypointensity on STIR image (c). Note several Gamna-Gandy siderotic splenic bodies due to advanced portal hypertension
insightsimaging.springeropen.com • CC-by-2.0
MR imaging in
liver cirrhosis: classical and new approaches. Fibrosis. Transverse fat suppression T1W spoiled GRE image after administration of contrast media shows reticular pattern of the fibrotic bands surrounding regenerative nodules
insightsimaging.springeropen.com • CC-by-2.0
nicht verwechseln mit: noduläre regenerative Hyperplasie
Radiopaedia • CC-by-nc-sa 3.0 • de

Regenerative liver nodules are a form of non-neoplastic nodules that arise in a cirrhotic liver.

Terminology

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 . When there is an accumulation of iron in the nodules, they are called siderotic nodules.

Pathology

RNs form in the setting of necrosis or regenerative nodules can be of three types :

  • micronodules <3 mm
  • macronodules >3 mm
  • giant RNs > 5 cm (rare)

Radiographic features

Regenerative nodules appear as round, well-defined nodules (usually in the thousands) present throughout the liver with surrounding fibrosis .

On post-contrast CT and MRI, regenerative nodules 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.

CT

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

Contrast injection into the superior mesenteric artery (after arterial vascular access). Regenerative nodules are generally visualized as enhancing nodules surrounded by lower attenuation thin septa.

CT hepatic arteriography

Contrast injection into the common hepatic artery (after arterial vascular access). Regenerative nodules are generally visualized as nonenhancing nodules surrounded by enhancing fibrous septa.

CT hepatic arteriography is considered more sensitive than the former in depicting regenerative nodules.

MRI

RNs are common in a cirrhotic liver :

  • T1: variable
  • T1 in-phase/out-of-phase: loss of signal on out-of-phase if fat-containing
  • T2: hypointense
  • T2*: hypointense
  • T1C+: usually do not enhance or enhance less than the liver parenchyma

Treatment and prognosis

Regenerative nodules may progress to dysplastic nodules or hepatocellular carcinoma .

Practical points

  • fat-containing regenerative nodules are usually multiple; a solitary fat-containing nodule is concerning for dysplasia/malignancy

See also

Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu Regeneratknoten der Leber:
Leberzirrhose
 
Wikipedia • CC BY-SA 3.0
noduläre
regenerative Hyperplasie
aacijournal.biomedcentral.com • CC-by-4.0
dysplastische
Leberknoten
bmcmedimaging.biomedcentral.com • CC-by-4.0