ReviewHepatic capsular retraction: An updated MR imaging review
Section snippets
Background
Hepatic capsular retraction is a morphologic descriptor referring to invagination or focal flattening of the typical smooth contour of the liver capsule. It is a rare finding on cross-sectional imaging, seen in approximately 2% of patients [1]. While once believed to be exclusively correlated with hepatic malignancy, capsular retraction is in fact also associated with several types of benign lesions and with post-treatment changes [[2], [3], [4]]. Although nonspecific, the finding of hepatic
Intrahepatic cholangiocarcinoma
Cholangiocarcinoma is the second most common primary liver cancer and can arise from either the intrahepatic or extrahepatic bile ducts. Intrahepatic cholangiocarcinoma is less common than the extrahepatic form, although its prevalence in the United States is increasing [9]. Chronic biliary inflammation is the most common risk factor for the development of intrahepatic cholangiocarcinoma; this chronic inflammation may be caused by inflammatory conditions such as primary sclerosing cholangitis
Hepatic hemangioma
Hemangiomas, the most common benign liver neoplasms, arise from proliferative vasculature and are supported by a fibrous matrix. They are incidentally discovered in 2.5% to 3.4% of imaged lesions [35,36]. Capsular retraction can be seen in association with hepatic hemangiomas in three different settings: giant hemangiomas [37], hemangiomas occurring in patients with liver cirrhosis [5,[38], [39], [40]], and sclerosing hemangiomas (also called thrombosed or hyalinized hemangiomas) [[38], [39],
“Pseudocirrhosis” after treatment for hepatic metastases
Pseudocirrhosis in the setting of treated metastatic disease can be the result of reactive changes in both the lesion itself and in the uninvolved liver parenchyma after nonoperative therapy (Fig. 8). Post-treatment changes contributing to capsular retraction include necrosis, fibrosis, and atrophy of the lesion [1,2,34,50,51], as well as nodular regenerative hyperplasia in the liver parenchyma adjacent to the treated tumor [[51], [52], [53]]. Capsular retraction is most frequently described
Chronic biliary obstruction
Chronic biliary obstruction is often associated with hepatic capsular retraction and may result from various causes including traumatic, vascular, inflammatory, infectious, and neoplastic processes. The exact mechanism of capsular retraction varies by specific process; two representative processes are discussed in further detail below.
Mimickers of capsular retraction
Since the identification of capsular retraction can potentially lead to further imaging or surgical intervention, it is important to distinguish true capsular retraction from pseudo capsular retraction. One commonly seen cause of pseudo capsular retraction is extrinsic compression of the hepatic capsule by the adjacent ribs or diaphragm; this finding can be easily confirmed with review of multiplanar reformats. Similarly, penetrating or blunt trauma may distort the hepatic parenchyma to give an
Conclusion
Hepatic capsular retraction is associated with a variety of conditions and is a useful feature in liver imaging. It may be indicative of an underlying fibrotic process (either neoplastic or non-neoplastic in origin) or of focal parenchymal atrophy in response to vascular insult or chronic biliary obstruction. By itself, capsular retraction provides a useful list of potential differential diagnosis considerations. However, when combined with other imaging findings and clinical data, the presence
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Conflicts of Interest
The authors have no conflicts of interest to declare.
Acknowledgement
None.
References (69)
- et al.
Liver lesions with hepatic capsular retraction
Semin. Ultrasound, CT MRI.
(2009) - et al.
[Liver capsule retraction adjacent to a circumscribed liver lesion: review of 26 cases with histological confirmation]
J. Radiol.
(2009) Capsular retraction of the liver in malignant tumor of the biliary tract MRI findings
Clin. Imaging
(1994)- et al.
Imaging findings of primary hepatic angiosarcoma on gadoxetate disodium-enhanced liver MRI: comparison with hepatic haemangiomas of similar size
Clin. Radiol.
(2018) - et al.
Hepatic metastases from gastric hepatoid adenocarcinoma: an unusual cause of capsular retraction of the liver
Diagn. Interv. Imaging
(2016) - et al.
Hepatic metastasis from basal cell carcinoma: a rare location with an unreported presentation
Diagn. Interv. Imaging
(2018) Liver mass evaluation in patients without cirrhosis
Radiol. Clin. North Am.
(2015)- et al.
Benign tumors of the liver
Med. Clin. North Am.
(1975) - et al.
Prevalence and clinical outcome of hepatic haemangioma with specific reference to the risk of rupture: A large retrospective cross-sectional study
Dig. Liver Dis.
(2016) - et al.
Cavernous hemangioma with extensive sclerosis masquerading as intrahepatic cholangiocarcinoma — a pathologist’s perspective
Radiol. Case Rep.
(2014)