title: Anomalous branching pattern of the portal vein: right posterior portal vein originating from the left portal vein.
abstract: OBJECTIVE
  To introduce a rare variant branching pattern of the portal vein with clinical relevance.
  
  
  METHODS
  A 55-year-old man was examined by contrast-enhanced computed tomography to investigate the cause of fever and mildly elevated hepatic enzyme levels.
  
  
  RESULTS
  Based on computed tomography, liver abscesses were identified which may have caused the fever and elevated hepatic enzyme levels. And a variation in the branching pattern of the portal vein was also detected in this patient, which has not been reported previously; the right posterior portal vein originated from the end of the horizontal part of the left portal vein. Identification of this rare branching pattern of the portal vein prior to hepatectomy, liver transplantation, and portal vein embolization is considered important to prevent complications.
  
  
  CONCLUSIONS
  A rare variant in which the right posterior portal vein originated from the left portal vein was identified. Recognition of this variant may be important prior to surgical or interventional radiological strategies.
authors.affiliation: Department of Radiology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, Japan. koyasaka@gmail.com.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Yasaka
authors.affiliation: Department of Radiology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Akai
authors.affiliation: Department of Radiology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kiryu
mesh_terms: D003287:Contrast Media; D006801:Humans; D033162:Incidental Findings; D008100:Liver Abscess / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000002:abnormalities*; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media
keywords: Hepatectomy; Liver transplantation; Portal vein; Portal vein embolization; Variation