Imaging findings of bile duct hamartomas: a case report and literature review.

Bile duct hamartomas (BHs), also called von Meyenburg complex (VMC), are benign biliary malformations that originate from disorganization of the small intrahepatic bile ducts. This disorganization is often associated with the abnormal involution of embryonic ductal end plates in the liver. This is clinically significant, as the development of BHs can cause diagnostic confusion with liver metastases and small hepatocellular carcinoma (SHCC). Currently, we report a specific case of BHs and review the literature to better define and diagnose BHs. In the following case, a 37 year-old male bearing a lesion in his liver is presented and undergoes both radiological and pathological diagnosis. The lesion is preliminarily suspected to be a hepatic hemangioma by examination of conventional ultrasound (US), contrast enhanced ultrasound (CEUS), computerized tomographic scanning (CT) and magnetic resonance imaging (MRI). However, SHCC is suspected by follow-up analysis of US and CEUS, due to the patient's background history of hepatitis B and growth of the lesion and a tumor-feeding vessel in BHs via CEUS. However, BHs are finally diagnosed by biopsy pathology under the guidance of ultrasound. Therefore, we believe pathology is imperative for correct diagnosis of BHs over other similar diseases when the imaging findings are atypical. Here we report the novel and unique detection of a tumor-feeding vessel, which mimicked SHCC strongly, during the course of CEUS. We also present a comprehensive review of the previous reported radiological examination related to BHs.