title: Routes for virtually guided endoscopic liver resection of subdiaphragmatic liver tumors.
abstract: OBJECTIVE
  Laparoscopic and thoracoscopic/laparoscopic hepatectomy is a safe procedure that has potential advantages over open surgery. However, deeply positioned liver tumors require expert laparoscopic and thoracoscopic/laparoscopic hepatectomy techniques. Using simulated preoperative three-dimensional virtual endoscopy (P3DVE) guidance, we demonstrate herein that a thoracoscopic approach (TA), thoracoscopic-laparoscopic approach (TLA), and laparoscopic approach (LA) are all feasible and safe routes for performing pure laparoscopic and thoracoscopic/laparoscopic resection of liver tumors located in the 4a, 7, and 8 liver subdiaphragmatic areas.
  
  
  METHODS
  Thirty-eight patients underwent laparoscopic and thoracoscopic/laparoscopic partial liver resection (TA 13 cases, TLA two cases, and LA 23 cases) of the subdiaphragmatic area at Showa University Hospital. All surgical approaches were preoperatively determined based on preoperative 3D virtual endoscopic simulation (P3DVES) visualization and findings using the image processing software SYNAPSE VINCENT(®).
  
  
  RESULTS
  Laparoscopic and thoracoscopic/laparoscopic liver resection was successfully performed for all cases under P3DVE instruction. The mean operative times using TA, TLA, and LA approaches were 193, 185, and 190 min, respectively. Mean blood loss during TA, TLA, and LA was 179, 138, and 73 g, respectively. No patients required conversion to open surgery, and there were no deaths, although there were three cases of Clavien-Dindo grade I in TA along with three cases of grade I and one case of grade II in LA.
  
  
  CONCLUSIONS
  TA, TLA, and LA routes performed under P3DVE instruction are feasible and safe to perform for pure laparoscopic and thoracoscopic/laparoscopic liver resection in selected patients with lesions located in the hepatic subdiaphragmatic area.
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan. takejp@wb4.so-net.ne.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Aoki
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Murakami
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Fujimori
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Tomotake
authors.initials: T
authors.lastname: Koizumi
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Enami
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Kusano
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Matsuda
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Nogaki
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Wada
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Hakozaki
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Goto
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterological & General Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawaku, Tokyo, 142-8666, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Otsuka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D025321:Surgery, Computer-Assisted / Q000379:methods*; D014057:Tomography, X-Ray Computed
keywords: 3D virtual endoscopic simulation; Laparoscopic hepatectomy; Subdiaphragmatic liver tumor; Thoracoscopic–laparoscopic hepatectomy; Video-assisted thoracoscopic surgery-hepatectomy