title: A study of the right intersectional plane (right portal scissura) of the liver based on virtual left hepatic trisectionectomy.
abstract: BACKGROUND
  Left hepatic trisectionectomy is a challenging procedure. For an anatomically correct resection, it is necessary to have understanding of the right intersectional plane; however, little is known on this issue. The purpose of this study was to investigate the 3D anatomy of the right intersectional plane and to enable safe and precise left trisectionectomy.
  
  
  METHODS
  A virtual left trisectionectomy was performed using 3D-processing software, in patients who underwent computed tomography. The reconstructed images were reviewed, and attention was paid to the extent of the right hepatic vein (RHV) exposure on the transected plane and the type of the inferior right hepatic vein (IRHV).
  
  
  RESULTS
  Of the 200 study patients, 109 (54.5 %) patients showed complete exposure of the RHV on the transected plane, whereas the remaining 91 exhibited partial exposure. In the 109 patients with complete exposure, 58 (53.2 %) patients had no IRHV and the remaining 51 had a small IRHV. None of the patients had a large IRHV. In contrast, of the 91 patients with partial exposure, only 10 (11.0 %) patients had no IRHV, 35 (38.5 %) had a small IRHV, and 46 (50.5 %) patients had a large IRHV. The incidence of IRHV types was significantly different between the two groups (P < 0.001).
  
  
  CONCLUSIONS
  The RHV does not always run along the right intersectional plane, i.e., the vein is not always fully exposed on the transected plane even after anatomically correct left trisectionectomy. The extent of the RHV exposure is closely related to the type of the IRHV.
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-Ku, Nagoya, 466-8550, Japan.
authors.forename: Fumiya
authors.initials: F
authors.lastname: Sato
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Igami
authors.forename: Tomoki
authors.initials: T
authors.lastname: Ebata
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Gen
authors.initials: G
authors.lastname: Sugawara
authors.forename: Takashi
authors.initials: T
authors.lastname: Mizuno
authors.forename: Masato
authors.initials: M
authors.lastname: Nagino
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003198:Computer Simulation; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006503:Hepatic Veins / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008099:Liver / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D055815:Young Adult