title: Image guidance during abdominal exploration for recurrent colorectal cancer.
abstract: BACKGROUND
  Real-time intraoperative image guidance has been successfully applied to malignancies of the head, neck and central nervous system. Few attempts have been made to apply this technology to gastrointestinal cancers. Our purpose was to determine if a computer-assisted navigation system could be accurately used at the time of abdominal exploration.
  
  
  METHODS
  Fourteen patients with resectable recurrent colorectal cancer underwent computer tomography (CT) imaging of the abdomen and pelvis. The CT images were uploaded to a StealthStation (Medtronic, Inc., Minneapolis, MN), a device that tracks the motion of a handheld probe in the operating field and displays its position, in real time, on the uploaded images. Various anatomic points were utilized to match, or register, the patient to the images in the navigation system. After four or more anatomic points were registered, the accuracy of the registration process was computed by the navigation system and reported as the global error.
  
  
  RESULTS
  A total of 23 different anatomic structures were used for registration. The median number of points used for registration per patient was 6.5 (range 5-9). The anatomic sites most commonly used were the anterior superior iliac spines, aortic bifurcation, sacral promontory, symphysis pubis, and iliac artery bifurcation. The median global error was 10.0 mm (range 6.7 mm-27.0 mm).
  
  
  CONCLUSIONS
  Computer-assisted navigation systems can be used to accurately deliver image guidance at the time of abdominal exploration. Future work will be directed at determining the value of this technology in the localization and resection of tumors.
authors.affiliation: Department of Surgery, Division of Surgical Oncology, The Ohio State University, Columbus, Ohio, USA.
authors.forename: Ergun
authors.initials: E
authors.lastname: Kocak
authors.forename: Osama
authors.initials: O
authors.lastname: Al-Saif
authors.forename: Martin
authors.initials: M
authors.lastname: Satter
authors.forename: Mark
authors.initials: M
authors.lastname: Bloomston
authors.forename: Shahab F
authors.initials: SF
authors.lastname: Abdessalam
authors.forename: Joseph
authors.initials: J
authors.lastname: Mantil
authors.forename: A Ardeshir
authors.initials: AA
authors.lastname: Goshtasby
authors.forename: Edward W
authors.initials: EW
authors.lastname: Martin
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery*; D009367:Neoplasm Staging; D010865:Pilot Projects; D011857:Radiographic Image Interpretation, Computer-Assisted; D025321:Surgery, Computer-Assisted; D014057:Tomography, X-Ray Computed