title: Feasibility and Technique for Transvaginal Natural Orifice Transluminal Endoscopic Surgery Liver Resection: A Porcine Model.
abstract: BACKGROUND
  Natural orifice transluminal endoscopic surgery (NOTES) is a challenging minimally invasive procedure. Although laparoscopic techniques for liver resection are gaining acceptance worldwide, few studies have investigated NOTES liver resection. We used a porcine model to assess the feasibility and safety of transvaginal NOTES liver resection (TV NOTES LR).
  
  
  METHODS
  Nine female pigs underwent TV NOTES LR. A nonsurvival acute porcine model with general anesthesia was used in all cases. Using hybrid NOTES technique, we placed only 1 umbilical 12-mm umbilical trocar in the abdominal wall, which was used to create pneumoperitoneum. A laparoscope was then advanced to obtain intra-abdominal visualization. A 15-mm vaginal trocar was inserted under direct laparoscopic vision, and a flexible endoscope was introduced through the vaginal trocar. A long, flexible grasper and endocavity retractor were used to stably retract the liver. The liver edge was partially transected using energy devices inserted through the umbilical trocar. To transect the left lateral lobe, a flexible linear stapler was inserted alongside the vaginal trocar. A specimen extraction bag was deployed and extracted transvaginally. Blood loss, bile leakage, operative time, and specimen size were evaluated. Necropsy studies were performed after the procedures.
  
  
  RESULTS
  Eighteen transvaginal NOTES partial liver resections and 4 transvaginal NOTES left lateral lobectomies were successfully performed on 9 pigs. Mean operative time was 165.8 minutes, and mean estimated blood loss was 76.6 mL. All TV NOTES LRs were performed without complications or deaths. Necropsy showed no bile leakage from remnant liver.
  
  
  CONCLUSIONS
  Our porcine model suggests that TV NOTES LR is technically feasible and safe and has the potential for clinical use as a minimally invasive alternative to conventional laparoscopic liver resection.
authors.affiliation: *Department of Surgery, Division of General and Gastroenterological Surgery, Toho University School of Medicine, Omori, Tokyo, Japan †Department of Surgery, Division of Minimally Invasive Surgery, University of California, San Diego, CA.
authors.forename: Toshio
authors.initials: T
authors.lastname: Katagiri
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Otsuka
authors.forename: Santiago
authors.initials: S
authors.lastname: Horgan
authors.forename: Bryan J
authors.initials: BJ
authors.lastname: Sandler
authors.forename: Garth R
authors.initials: GR
authors.lastname: Jacobsen
authors.forename: Alisa M
authors.initials: AM
authors.lastname: Coker
authors.forename: Masaru
authors.initials: M
authors.lastname: Tsuchiya
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Maeda
authors.forename: Hironori
authors.initials: H
authors.lastname: Kaneko
mesh_terms: D000818:Animals; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data; D005240:Feasibility Studies; D005260:Female; D006498:Hepatectomy / Q000379:methods; D010535:Laparoscopy / Q000379:methods; D008099:Liver / Q000601:surgery*; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D061646:Operative Time; D012449:Safety; D013552:Swine; D014621:Vagina / Q000601:surgery*