title: Integrated MR-laparoscopy system with respiratory synchronization for minimally invasive liver surgery.
abstract: OBJECTIVE
  The laparoscope has been invaluable in minimally invasive surgery, but provides only a surface view of target tissue; therefore it is lacking internal tissue information. In combination with the laparoscope for visualizing the cross-sectional view of the tissue, MRI is superior to ultrasonography or X-ray CT, because of its high soft-tissue contrast, arbitrary slice orientation and lack of radiation properties. Thus, we propose an integrated MR-laparoscopy system with a respiratory-synchronized navigation.
  
  
  METHODS
  A transmit/receive RF coil for localized MR imaging with a 0.5 T open-MRI was mounted onto the tip of an MR-compatible laparoscope. The signal detection of the coil was examined with an excised porcine liver sample, an agar phantom and the abdominal wall of a healthy volunteer. A real-time navigation system to compensate for respiratory motion was developed, and examined with a healthy volunteer.
  
  
  RESULTS
  The SNRs of the local MR images were 112, 62, and 62 in the liver sample, phantom, and volunteer. The navigation system successfully displayed the scope view, scope location and orientation, and MR images with respiratory-synchronized real time operation.
  
  
  CONCLUSIONS
  The MR-imaging and synchronization function of the proposed system seemed to be helpful for laparoscopic surgery.
authors.affiliation: Department of Gastroenterology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan. ymatsuok@med.kobe-u.ac.jp
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Matsuoka
authors.forename: Etsuko
authors.initials: E
authors.lastname: Kumamoto
authors.forename: Maki
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Takeshi
authors.initials: T
authors.lastname: Azuma
authors.forename: Akito
authors.initials: A
authors.lastname: Saito
authors.forename: Toshio
authors.initials: T
authors.lastname: Shibasaki
authors.forename: Kagayaki
authors.initials: K
authors.lastname: Kuroda
mesh_terms: D000818:Animals; D003199:Computer Systems; D004867:Equipment Design; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D020706:Laparoscopes; D010535:Laparoscopy / Q000379:methods*; D008107:Liver Diseases / Q000175:diagnosis* / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D019047:Phantoms, Imaging; D012016:Reference Values; D015203:Reproducibility of Results; D012119:Respiration; D013552:Swine; D055815:Young Adult