title: Investigation of C-arm cone-beam CT-guided surgery of the frontal recess.
abstract: OBJECTIVE
  A cone-beam CT (CBCT) imaging system based on a mobile C-arm (Siemens PowerMobil) incorporating a high-performance flat-panel detector (Varian PaxScan) has been developed in our laboratory. We hypothesize that intraoperative C-arm CBCT provides image quality and guidance performance sufficient to assist surgical approach to the frontal recess.
  
  
  METHODS
  A preclinical prospective study was conducted using six cadaver heads to assess the performance characteristics and the potential clinical utility of this imaging system.
  
  
  METHODS
  The mobile C-arm was employed for intraoperative CBCT guidance of the endoscopic approach to twelve frontal recesses.
  
  
  RESULTS
  The imaging system is capable of sub-mm 3D spatial resolution with bone and soft-tissue visibility and a field of view sufficient for guidance of head and neck surgery. The system can generate intraoperative, volumetric CT images rapidly with an acceptably low radiation exposure to the patient and with image quality sufficient for most surgical tasks. Moreover, the system is portable and compatible with the surgical setup, providing excellent access to the patient. Finally, the accuracy of the system is not bound to a registration process.
  
  
  CONCLUSIONS
  The ability to create updated images as surgery progresses introduces the concept of 'near-real-time' CT guidance for head and neck surgery. We found that the use of CBCT increased surgical confidence in accessing the frontal recess, resolved ambiguities with anatomical variations, and provided valuable teaching information to surgeons in training in both preoperative planning and correlation between tri-planar CT scans and intraoperative endoscopic findings.
authors.affiliation: Department of Surgical Oncology, University Health Network, Toronto ON, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Rafferty
authors.forename: J H
authors.initials: JH
authors.lastname: Siewerdsen
authors.forename: Y
authors.initials: Y
authors.lastname: Chan
authors.forename: D J
authors.initials: DJ
authors.lastname: Moseley
authors.forename: M J
authors.initials: MJ
authors.lastname: Daly
authors.forename: D A
authors.initials: DA
authors.lastname: Jaffray
authors.forename: J C
authors.initials: JC
authors.lastname: Irish
mesh_terms: D002102:Cadaver; D004724:Endoscopy / Q000379:methods*; D004867:Equipment Design; D005624:Frontal Bone / Q000000981:diagnostic imaging / Q000601:surgery*; D005626:Frontal Sinus / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D066298:In Vitro Techniques; D011446:Prospective Studies; D015203:Reproducibility of Results; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*; D014057:Tomography, X-Ray Computed