title: Precise anatomical resection of the ventral part of Segment VIII.
abstract: BACKGROUND
  Anatomical resection of the ventral part of Segment VIII (S8vent) is demanding and there are no accurate methods to identify the demarcation line inside the liver. The current authors have proposed a method to solve the problem.
  
  
  METHODS
  The tumor was located in the S8vent and was 4cm in size. One tributary of the middle hepatic vein (MHV), designated V8i, was running between S8vent and the dorsal part of Segment VIII (S8dor). Another tributary of the MHV, designated V8-5i, was running between S8vent and the ventral part of S5 (S5vent). About 5ml of indigo carmine dye was injected into the proximal part of P8vent. After the small tributary of V8-5i was exposed, it was followed all the way to the main trunk of the MHV. The portal pedicle of S8vent was then ligated and divided. Next, the V8i was gradually exposed from the distal MHV to its trunk.
  
  
  CONCLUSIONS
  A recent study showed that the subsegmental border visualized between the ventral and dorsal region always coincided with the plane of V8i, so the subsegmental plane can be divided along with V8i by preserving the very small tributaries near the liver surface and following them to determine where they meet as they run into V8i. Also, the landmark vein of V8-5i in the transverse S8-S5 intersegmental plane was determined for the first time.
  
  
  CONCLUSIONS
  Proposed here is a more accurate method of dividing the liver parenchyma along the intersegmental and intersubsegmental demarcation.
authors.affiliation: Hospital & Institute of Hepato-Biliary Surgery, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors.forename: Canhong
authors.initials: C
authors.lastname: Xiang
authors.affiliation: Hospital & Institute of Hepato-Biliary Surgery, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Hospital & Institute of Hepato-Biliary Surgery, Chinese PLA General Hospital, No. 28 Fuxing Road, Haidian District, Beijing 100853, China.
authors.forename: Jiahong
authors.initials: J
authors.lastname: Dong
authors.affiliation: Department of Surgery, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Sano
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, Japanese Red Cross Medical Center, University of Tokyo, 4-1-22 Hiroo, Shibuya-ku, Tokyo 150-8935 Japan. Electronic address: masatoshi.makuuchi@gmail.com.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Makuuchi
keywords: Anatomical resection; Precision surgery; Segment VIII