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Hepatobiliary scintigraphy is a nuclear imaging technique that permits evaluation of the liver and biliary system for acute and chronic cholecystitis, biliary atresia, biliary obstruction, and post-surgical biliary leak. These are diverse conditions that require definitive diagnoses prior to intervention. This activity reviews the indications and contraindications for hepatobiliary scintigraphy and highlights interprofessional considerations for patients undergoing evaluation of the liver and biliary system with nuclear imaging. Objectives: Describe the physiology of the hepatobiliary system. Review the indications and contraindications for hepatobiliary scintigraphy. Differentiate the common imaging findings associated with cholecystitis, biliary leak, biliary atresia, and biliary obstruction. Describe the importance of collaboration and communication between the interprofessional teams involved in the care of patients with hepatobiliary disease to hasten the diagnosis and management of patients with these pathologies. Access free multiple choice questions on this topic.

Hepatobiliary scintigraphy is a diagnostic nuclear medicine procedure which uses radiotracers to evaluate the biliary system and also, indirectly, the liver. The radiotracer first used was iminodiacetic acid (IDA), a lidocaine derivative initially investigated for cardiac scintigraphy. When its potential as a hepatobiliary imaging agent was realized, the term HIDA scan was coined. Since then, the original radiotracer has undergone several modifications, and the initial HIDA agent is no longer commercially available. HIDA and its current modern variants are administered intravenously, bound to albumin, transported to the liver, and excreted into the biliary system. The utility of hepatobiliary scintigraphy (HBS) is that the radiotracer follows the bilirubin metabolic pathway and excretion into the bile ducts.[1][2] As such, it has proven extremely useful in the diagnosis of acute cholecystitis, chronic gallbladder disease, biliary leaks, biliary obstruction, and biliary atresia. Ultrasound (US) remains the primary modality for initially assessing suspected biliary pathology. Ultrasound is readily available, fast, requires minimal patient preparation, avoids ionizing radiation, and may offer alternative diagnoses.[3][4] Despite these benefits, US can suffer from both suboptimal sensitivity and specificity in the assessment of biliary disorders, and thus HBS remains critical to the evaluation of patients with right upper quadrant pain and other symptoms of hepatobiliary disease.[5][6]

During a typical HBS, the patient will have exposure to 3 to 4 mSv of radiation which is roughly the amount of background radiation experienced in one year. For reference, a chest x-ray exposes the patient to 0.001 mSv of radiation while a computed tomography of the head requires 1 to 5 mSv.[17]

Nuclear imaging, like other imaging modalities, requires adherence to the 'as low as reasonably achievable' (ALARA) principle limiting patient radiation dose.[18] When the primary care provider/nurse practitioner orders a hepatobiliary scan, the nuclear radiologist should review the patient's previous imaging modalities, lab data, surgical history, and current medications. The nuclear medicine team must coordinate with the patient and the patient's medical providers including the nurse practitioner, physician assistant, and physician to ensure adequate patient preparation including appropriate time passage since the patient's most recent meal as well as risk assessment and possible cessation of medications that might interfere with biliary function.[2]