Evaluation of intrahepatic and extrahepatic biliary tree anatomy and its variation by magnetic resonance cholangiopancreatography in Odisha population: a retrospective study

Intrahepatic and extrahepatic anatomical knowledge is essential for pre procedural planning of liver transplantation, liver resection, complex biliary reconstruction and radiological biliary tree intervention. Indian data of biliary anatomy and its variation is scant in literature. The aim of our study is to find out the prevalence of common and uncommon pattern of biliary tree anatomy in magnetic resonance cholangiopancreatography (MRCP) in our population. A total of 1,038 cases of MRCP of population of Odisha were obtained from Picture Archiving and Communication System of the department and were reviewed by two senior radiologists for anatomical pattern and variations. The typical and most common pattern of right hepatic duct (RHD) branching was seen in 72.8% cases. The most common variant of RHD was trifurcation pattern of insertion of right anterior sectoral duct (RASD), right posterior sectoral duct and left hepatic duct (LHD) forming common hepatic duct (CHD) in 11.3% of cases. The common trunk of segment (SEG) II and III ducts joining the SEG IV duct was the most common LHD branching pattern in 90.3% of cases. The most common pattern of cystic duct was posterior insertion to middle third of CHD (42.8%). MRCP is the non-invasive imaging modality for demonstration of biliary duct morphology to prevent iatrogenic injury during hepatobiliary intervention and surgery.