title: Intraoperative cone-beam CT for guidance of temporal bone surgery.
abstract: OBJECTIVE
  To describe our preclinical experience with Cone Beam CT (CBCT) in image-guided surgery of the temporal bone.
  
  
  METHODS
  A mobile isocentric C-arm (PowerMobil, Siemens Medical Systems, Erlangen, Germany) modified to include a flat-panel detector (Varian Imaging Products, Palo Alto, CA) and a motorized orbit was developed to acquire multiple projections in rotation about a subject. Initial experiments imaging steel wire in air were used to investigate the system's spatial resolution in 3D image reconstruction. Subsequently temporal bone dissection was performed on five cadaver heads using the modified C-arm as an image guidance system.
  
  
  RESULTS
  We obtained a spatial resolution of 0.85 mm. The image acquisition time was 120 seconds and the radiation dose approximately one-tenth of a conventional CT scan.
  
  
  CONCLUSIONS
  CBCT provided submillimeter accuracy at high speed with low radiation dosage to offer utility as an intraoperative imaging system.
  
  
  CONCLUSIONS
  CBCT offers technology that approximates "near-real-time" image guidance.
  
  
  METHODS
  C-4.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Toronto, and Ontario Cancer Institute, Princess Margaret Hospital, University Health Network, Toronto, Ontario, Canada. markrafferty_5@sympatico.ca
authors.forename: Mark A
authors.initials: MA
authors.lastname: Rafferty
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Siewerdsen
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Chan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Daly
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Moseley
authors.forename: David A
authors.initials: DA
authors.lastname: Jaffray
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Irish
mesh_terms: D002102:Cadaver; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D066298:In Vitro Techniques; D016343:Monitoring, Intraoperative; D013506:Otologic Surgical Procedures / Q000379:methods*; D015203:Reproducibility of Results; D013701:Temporal Bone / Q000000981:diagnostic imaging* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*