Hepatobiliary Scintigraphy – Atlas of Cases of Traumatic Bile Leak

Introduction: Hepatobiliary Scintigraphy or ^99mTc-Hepatobiliary Iminodiacetic Acid (HIDA) scan utilizes the property of iminodiacetic acid or its variants to follow the bilirubin pathway and its subsequent excretion into the bile ducts. HIDA scan has been employed in a myriad of clinical conditions such as acute cholecystitis, chronic cholecystitis, sphincter of oddi dysfunction, biliary atresia, biliary stent patency and biliary leak. A potential role can be seen in traumatic biliary leak, a clinical situation which can occur both post operatively and following blunt abdominal trauma. It can guide a timely diagnosis and management, an can help reduce patient morbidity and mortality significantly.

Methods: Traumatic bile leak can be evaluated using functional imaging techniques like HIDA scan and the addition of anatomical correlation with SPECT/CT helps in further localization of the site of leak. HIDA can be used in the following scenarios: When the site of the leak is small and clinical suspicion is high; when there is a fluid collection detected by USG and its nature is to be characterized; when we need to differentiate controlled and uncontrolled bile leak; when there is disrupted anatomy of the abdominal organs after blunt abdominal trauma and anatomical imaging cannot detect the site of leak and lastly for follow-up to look for resolution of leak. Here we exemplify the beneficial role of ^99mTc-N-(3-bromo-2,4,6-trimethylacetanilide) iminodiacetic acid (Mebrofenin) combined with single photon emission tomography-computed tomography (SPECT-CT) in patients of traumatic injury to the hepato-biliary system, with the help of a series of cases which incurred blunt trauma abdomen.

Results: Pictorial demonstration of concepts of radiochemistry and imaging protocol of HIDA scan will be provided along with functional imaging of cases with suspected traumatic bile leak. The key headings would include: Overview of Hepatobiliary scintigraphy/ HIDA scan, Epidemiology of traumatic bile leak, Clinical cases utilizing ^99mTc- Hepatobiliary Iminodiacetic Acid (HIDA) scan in traumatic bile leak and discussion of pertinent findings and pitfalls.

Conclusions: In this exhibit, we present case scenarios that help realise the potential of ^99mTc- Hepatobiliary Iminodiacetic Acid (HIDA) scan combined with SPECT/CT in cases of suspected and proven traumatic bile leak.