title: Intraoperative C-arm cone-beam computed tomography: quantitative analysis of surgical performance in skull base surgery.
abstract: OBJECTIVE
  To determine whether incorporation of intraoperative imaging via a new cone-beam computed tomography (CBCT) image-guidance system improves accuracy and facilitates resection in sinus and skull-base surgery through quantification of surgical performance.
  
  
  METHODS
  Landmark identification and skull base ablation tasks were performed with a CBCT intraoperative image-guidance system in the experimental group and with image-guided surgery (IGS) alone based on preoperative computed tomography (CT) in the control group.
  
  
  METHODS
  Six cadaveric heads underwent preoperative CT imaging and surgical planning identifying surgical targets. Three types of surgical tasks were planned: landmark point identification, line contour identification, and volume drill-out. Key anatomic structures (carotid artery and optic nerve) were chosen for landmark identification and line contour tasks. Complete ethmoidectomy, vidian corridor drill-out, and clival resection were performed for volume ablation tasks. The CBCT guidance system was used in the experimental group and performance was assessed by metrics of target registration error, sensitivity, and specificity of excision.
  
  
  RESULTS
  Significant improvements were seen for point identification and line tracing tasks. Additional resection was performed in 67% of tasks in the CBCT group, and qualitative feedback indicated unequivocal improvement in confidence for all tasks. In review of tasks in the control group, additional resection would have been performed in 35% of tasks if an intraoperative image was available.
  
  
  CONCLUSIONS
  An experimental prototype C-arm CBCT guidance system was shown to improve surgical precision in the identification of skull base targets and increase accuracy in the ablation of surgical target volumes in comparison to using IGS alone.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Stella
authors.initials: S
authors.lastname: Lee
authors.forename: Gary L
authors.initials: GL
authors.lastname: Gallia
authors.forename: Douglas D
authors.initials: DD
authors.lastname: Reh
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schafer
authors.forename: Ali
authors.initials: A
authors.lastname: Uneri
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Mirota
authors.forename: Sajendra
authors.initials: S
authors.lastname: Nithiananthan
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Otake
authors.forename: J Webster
authors.initials: JW
authors.lastname: Stayman
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zbijewski
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Siewerdsen
mesh_terms: D059925:Anatomic Landmarks; D002102:Cadaver; D054893:Cone-Beam Computed Tomography; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D016343:Monitoring, Intraoperative / Q000295:instrumentation; D011786:Quality Control; D012680:Sensitivity and Specificity; D019291:Skull Base / Q000000981:diagnostic imaging* / Q000601:surgery*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013647:Task Performance and Analysis