Magnetic resonance and retrograde endoscopic cholangiopancreatography-based identification of biliary tree variants: are there type-related variabilities among the Saudi population?

PURPOSE: This study investigated biliary tree patterns in a Saudi Arabian population to identify common anatomical variations to establish a common ground for improved surgical practice and to avoid unexpected complications. We consider this type of investigation clinically important because the findings are valuable for pre-surgical planning in a broad range of procedures, including laparoscopic cholecystectomy and liver transplantation.

METHODS: We conducted an imaging-based retrospective cross-sectional study involving 150 patients who underwent endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography for different indications at King Fahd Hospital of the University between January 2011 and December 2014.

RESULTS: Typical right hepatic duct (RHD) tributaries were observed in 56% of patients and typical left hepatic duct (LHD) anatomy was detected in 81.4% of patients. The typical anatomical pattern for the cystic duct was found in 72% of patients.

CONCLUSIONS: Our findings showed that types A1 and A3b were the two most common variations in the RHD, whereas those in LHD were types B1 (segment IV duct opens to the LHD), and B2 (segment IV duct opens to the common hepatic duct separately). Although the angular type was the most prevalent among cystic duct variations, there were many differences in the types of variations observed. The findings somewhat correlated with those of other studies, suggesting that the normal biliary tree anatomy is similar among the Saudi population and in other ethnic groups.