Bile Duct and Gallbladder

Disorders of the gallbladder and bile ducts are not uncommon in the pediatric population. Although ultrasound is typically the first-line imaging modality employed in the workup of right upper quadrant pain or suspected hepatobiliary diseases, magnetic resonance (MR) imaging can be utilized for evaluation of bile duct and gallbladder disorders in pediatric patients. MR imaging can provide excellent visualization of these structures and allow comprehensive evaluation of the biliary system and possible concurrent liver disease without potentially harmful ionizing radiation associated with other imaging modalities such as CT. MR imaging sequences such as magnetic resonance cholangiopancreatography (MRCP) and use of hepatobiliary contrast agents can provide a noninvasive way of evaluating the intrahepatic and extrahepatic bile ducts. Up-to-date working knowledge of techniques and tools available to perform MR imaging of the biliary system and familiarity with common disease processes that are encountered in the pediatric population is essential. Therefore, in this chapter, MR imaging techniques for evaluating bile duct and gallbladder anatomy are discussed followed by the review of bile duct and gallbladder anatomy including embryology, normal development, and anatomic variants. In addition, various congenital and acquired disorders affecting infants and children are discussed including clinical features and characteristic MR imaging findings.