Hepatic von Meyenburg Complexes: Imaging Findings

Biliary hamartomas are uncommon benign malformations of the bile ducts. Biliary hamartomas, also known as biliary microhamartomas or referred to as von Meyenburg complexes (VMCs) are composed of disorganized bile ducts and fibrocollagenous stroma occurs in 30% of patients. VMCs are usually multiple, round or irregular consist of dilated or branching bile ducts, often small (up to 10 mm) scattered throughout the liver. These lesions are often discovered incidentally at imaging, laparotomy, or autopsy with no specific clinical manifestation. Imaging appearance of VMCs often varies. On ultrasound, they may be hypoechoic, hyperechoic, or mixed echogenicity structures with posterior echo enhancement or comet tail echoes. CT shows hypodense, small hepatic nodules, scattered throughout both liver lobes with no enhancement in most of the cases. On MRI, VMCs are numerous intrahepatic tiny cystoid lesions, reveal hypointensity on T1-weighted and hyperintensity on T2-weighted pulse sequences as compared to surrounding parenchyma with negligible enhancement on early and late post-gadolinium images. MRCP is helpful in the assessment of the ductal system and differentiating VMCs from intrabiliary ductal pathology such as Caroli’s disease. No communication exists between the hamartomas and the draining bile ducts. The spectrum of differential diagnose of VMCs includes; liver metastasis characterized as well to ill-defined multiple lesions often show peripheral rim enhancement; diffuse hepatocellular carcinoma often seen as discrete enhancing lesions in a cirrhotic liver and are seldom cystic and simple hepatic cysts which are round, often varies in number, size and location. Histopathology often confirms the benign nature of the tumor. However typical imaging findings and relative long term imaging follow-up that addresses identical findings are highly suggestive of VMCs.