title: Tumor ablation therapy of liver cancers with an open magnetic resonance imaging-based navigation system.
abstract: BACKGROUND
  As minimally invasive treatments for liver cancers, percutaneous ablation therapies represent a valid alternative to liver resections, especially in patients with poor liver function. Recently, image-guided surgical and interventional procedures using open magnetic resonance imaging (MRI) have been introduced.
  
  
  METHODS
  We performed percutaneous ablation therapy for 51 nodules of liver cancer in 34 patients using a navigation system based on open MRI. During the ablation therapy, the ultrasonography (US) probe, needle, and tumor were displayed on the MR image. Immediately after the procedure, the therapeutic effect was evaluated by open MRI.
  
  
  RESULTS
  In all cases, percutaneous puncture into the tumors was successful, even in the case of tumor undetectable by US. Mean fiducial registration error was approximately 3 mm. MR images captured after the procedure clearly demonstrated the ablated area. No mortality or major complications occurred, except for mild hemorrhage, pyrexia, and ascites.
  
  
  CONCLUSIONS
  We developed a novel navigation system integrating US and MR images using open MRI for percutaneous ablation therapy of liver cancers. The presented system allows a safe and accurate approach to liver cancers, especially certain tumors that cannot be adequately visualized by US, and an evaluation of therapeutic results immediately after the procedures.
authors.affiliation: Department of Future Medicine and Innovative Medical Information, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan. maedat@dem.med.kyushu-u.ac.jp
authors.forename: Takashi
authors.initials: T
authors.lastname: Maeda
authors.forename: Jaesung
authors.initials: J
authors.lastname: Hong
authors.forename: Kozo
authors.initials: K
authors.lastname: Konishi
authors.forename: Takanori
authors.initials: T
authors.lastname: Nakatsuji
authors.forename: Takefumi
authors.initials: T
authors.lastname: Yasunaga
authors.forename: Yo-ichi
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Akinobu
authors.initials: A
authors.lastname: Taketomi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kotoh
authors.forename: Munechika
authors.initials: M
authors.lastname: Enjoji
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nakashima
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanoue
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Maehara
authors.forename: Makoto
authors.initials: M
authors.lastname: Hashizume
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D017115:Catheter Ablation; D003110:Colonic Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary / Q000628:therapy*; D053783:Magnetic Resonance Imaging, Interventional; D008297:Male; D008875:Middle Aged; D013238:Stereotaxic Techniques; D025321:Surgery, Computer-Assisted; D018084:Ultrasonography, Interventional