BACKGROUND: Among the intrahepatic bile ducts, the biliary system of the left medial sectional bile duct (B4) is known to have relatively complex patterns.
METHODS: The records of 500 patients who had been diagnosed as having hepato-pancreatico-biliary disease were retrospectively studied for anatomical biliary variations of the left liver with special reference to the drainage system of B4 using magnetic resonance images.
RESULTS: The left hepatic duct was present in 494 patients (98.8%), whereas it was lacking in 6 patients (1.2%), and these patients exhibited the following B4 confluence patterns: B4 drained into the common hepatic duct in 2 patients (.4%), the right anterior sectional bile duct in 3 patients (.6%), and the right posterior sectional bile duct in 1 patient (.2%). The left hepatic duct was absent more frequently in patients with portal venous variations than in patients with a common branching pattern (8.2% vs .4%, P = .0011).
CONCLUSION: The presently reported data are useful for obtaining a better understanding of the surgical anatomy of the biliary system of the left liver. (C) 2015 Elsevier Inc. All rights reserved.