title: Establishment of a rat model: Associating liver partition with portal vein ligation for staged hepatectomy.
abstract: BACKGROUND
  We adapted the anatomically oriented parenchyma-preserving resection technique for associating liver partition with portal vein ligation (PVL) for staged hepatectomy (ALPPS) in rats and examined the role of revascularization in intrahepatic size regulation.
  
  
  METHODS
  We performed the procedures based on anatomic study. The ALPPS procedure consisted of a 70% PVL (occluding the left median, left lateral, and right lobes), parenchymal transection (median lobe) and partial (10%) hepatectomy (PHx; caudate lobe). The transection effect was evaluated by measuring the extent of hepatic atrophy or regeneration of individual liver lobes in the ALPPS and control groups (70% PVL and 10% PHx without transection). The survival rates after stage II resection and collateral formation within the portal vein system was examined.
  
  
  RESULTS
  Anatomic study revealed a close spatial relationship between the demarcation line and the middle median hepatic vein. This enabled placing the transection plane without injuring the hepatic vein. Transection was achieved via stepwise clamping, followed by 2-3 parenchyma-preserving piercing sutures on both sides of the clamp. Ligated liver lobes atrophy was significantly enhanced after ALPPS compared with the control group. In contrast, both a significantly greater relative weight of the regenerated lobe and proliferation index on the first postoperative day were observed. All animals tolerated stage II-resection without complications. Portoportal collaterals were only observed in the control group.
  
  
  CONCLUSIONS
  We developed an anatomically precise technique for parenchymal transection. The lack of a dense vascular network between the portalized and deportalized lobes may play an important role in accelerating regeneration and atrophy augmentation.
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Wei
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany.
authors.forename: Tianjiao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Department of Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany.
authors.forename: Sara
authors.initials: S
authors.lastname: Zafarnia
authors.affiliation: Fraunhofer Institute for Medical Image Computing MEVIS, Bremen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Schenk
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany.
authors.forename: Chichi
authors.initials: C
authors.lastname: Xie
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany.
authors.forename: Chunyi
authors.initials: C
authors.lastname: Kan
authors.affiliation: Institute of Pathology, Chemnitz Hospital, Chemnitz, Germany.
authors.forename: Olaf
authors.initials: O
authors.lastname: Dirsch
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany.
authors.forename: Utz
authors.initials: U
authors.lastname: Settmacher
authors.affiliation: Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany. Electronic address: Uta.Dahmen@med.uni-jena.de.
authors.forename: Uta
authors.initials: U
authors.lastname: Dahmen
mesh_terms: D000818:Animals; D006498:Hepatectomy / Q000379:methods*; D008026:Ligation; D008099:Liver / Q000098:blood supply / Q000502:physiology / Q000601:surgery*; D008115:Liver Regeneration; D008297:Male; D023421:Models, Animal; D011169:Portal Vein / Q000601:surgery*; D051381:Rats; D011917:Rats, Inbred Lew