Hepatobiliary imaging and its pitfalls

Since the advent of real-time ultrasound more than 20 years ago, it has remained the modality of choice for evaluating the gallbladder and biliary ducts, particularly in the setting of acute abdominal pain. Its ready availability, safety with no ionizing radiation, portability, and high sensitivity and accuracy for detecting gallstones and biliary dilatation make it the modality of choice. It also permits examination of multiple adjacent organ systems, including the liver, kidney, pancreas, duodenum, and the peritoneal cavity, which may be the true cause of a patient's symptoms. In general, ultrasound has become a triage examination for patients who present with acute upper abdominal pain, especially in the right upper quadrant. The most common emergency department requisition reads "right upper quadrant pain, rule out cholecystitis."