title: Biliary tract variations of the left liver with special reference to the left medial sectional bile duct in 500 patients.
abstract: 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).
  
  
  CONCLUSIONS
  The presently reported data are useful for obtaining a better understanding of the surgical anatomy of the biliary system of the left liver.
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Furusawa
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan. Electronic address: kbys@shinshu-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Kobayashi
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Takahide
authors.initials: T
authors.lastname: Yokoyama
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Shimizu
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Motoyama
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Kanai
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Norikazu
authors.initials: N
authors.lastname: Arakura
authors.affiliation: Department of Radiology, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Yamada
authors.affiliation: Division of Radiology, Shinshu University Hospital, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kitou
authors.affiliation: Department of Surgery, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Miyagawa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D063405:Anatomic Variation; D001653:Bile Ducts, Intrahepatic / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008099:Liver; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
keywords: Biliary tract variation; Left medial sectional bile duct; Portal venous variation