title: Evaluation of laparoscopic liver resection with two different Nd:YAG lasers for future use in a high-field open MRI.
abstract: OBJECTIVE
  Laparoscopic liver surgery is a safe and feasible technique for the treatment of benign and malignant liver tumors and has been well established at many specialized centers. Many different techniques of tissue dissection have been developed. As an alternative various lasers have been applied to conventional liver resections. Laser surgery is potentially beneficial for laparoscopic liver resection, allowing parenchymal dissection and vessel coagulation. A second advantage is the non-ferromagnetic character of this instrument, which facilitates magnetic resonance (MR)-guided interventions. In this study two different Nd:YAG lasers were evaluated for laparoscopic liver resection in a porcine model. In other studies this technique will be transferred into an interventional open MRI for image-guided liver resection.
  
  
  METHODS
  We used 1064-nm and 1318-nm Nd:YAG lasers for laparoscopic wedge, segmental, and left lateral liver lobe resection. During the intervention blood loss, resection time, and cardiopulmonary parameters were quantified. The resected specimen underwent histomorphometric analysis for thermal tissue effects, including parenchymal carbonization, necrosis, and vessel coagulation.
  
  
  RESULTS
  The resected volume showed a positive correlation with intraoperative blood loss, which increased from wedge resection (245 mL, SD +/- 71 mL) and segment resection (325 mL), to left lateral resection (455 mL). Total parenchymal dissection was slightly faster with the 1064-nm Nd:YAG laser (9 min, SD +/- 5 min) compared with the 1318-nm Nd:YAG laser (11 min, SD +/- 4 min). Thermally-induced vessel sealing was shown for liver veins and arteries to a maximum diameter of 2 mm.
  
  
  CONCLUSIONS
  Laparoscopic liver resection with both Nd:YAG lasers is a safe and feasible technique, allowing parenchymal dissection and coagulation. The 1064-nm Nd:YAG laser showed increased tissue damage with more effective coagulation capability than the 1318-nm Nd:YAG laser. Because of its non-ferromagnetic characteristics, laser-based laparoscopic liver resection is potentially useful for image-guided surgery in an open MRI.
authors.affiliation: Department of General, Visceral, and Transplantation Surgery, Charité Campus Mitte, University Medicine Berlin, Berlin, Germany. sascha.chopra@charite.de
authors.forename: Sascha Santosh
authors.initials: SS
authors.lastname: Chopra
authors.forename: Georg
authors.initials: G
authors.lastname: Wiltberger
authors.forename: Ulf
authors.initials: U
authors.lastname: Teichgraeber
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papanikolaou
authors.forename: Michael
authors.initials: M
authors.lastname: Schwabe
authors.forename: Sven
authors.initials: S
authors.lastname: Schmidt
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Fikatas
authors.forename: Florian
authors.initials: F
authors.lastname: Streitparth
authors.forename: Carsten
authors.initials: C
authors.lastname: Philipp
authors.forename: Florian
authors.initials: F
authors.lastname: Wichlas
authors.forename: Christian
authors.initials: C
authors.lastname: Seebauer
authors.forename: Guido
authors.initials: G
authors.lastname: Schumacher
mesh_terms: D000818:Animals; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D010535:Laparoscopy; D053685:Laser Therapy / Q000295:instrumentation*; D053844:Lasers, Solid-State; D008279:Magnetic Resonance Imaging; D023421:Models, Animal; D013552:Swine