title: The impact of fiducial distribution on headset-based registration in image-guided sinus surgery.
abstract: OBJECTIVE
  The objective of this study was to assess registration error due to fiducial configuration for the ENT headsets for the CBYON Suite (CBYON, Mountain View, CA) and InstaTrak (GEMS Navigation and Visualization, Waukesha, WI).
  
  
  METHODS
  Axial CT scans (1-mm slice thickness) were obtained of for 24 cadaveric heads using the CBYON headset and for 23 cadaveric heads using the GEMS headset. The CBYON and GEMS NAV software were used to calculate the fiducial registration error (FRE). Fiducial localization error (FLE) was estimated from FRE. Theoretical target registration error (TRE) was calculated at 11 targets.
  
  
  RESULTS
  The FRE for CBYON and GEMS NAV was 0.69 mm and 0.27 mm, respectively. The theoretical TRE for CBYON and GEMS NAV was 0.41 mm and 0.30 mm, respectively. The theoretical TRE was greater at targets posterior in the sinus cavities.
  
  
  CONCLUSIONS
  Theoretical TRE values for both ENT headsets are less than clinically observed TRE. Clinically observed TRE is likely due to repositioning accuracy.
  
  
  METHODS
  B-2.
authors.affiliation: Head and Neck Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
authors.forename: P Daniel
authors.initials: PD
authors.lastname: Knott
authors.forename: Calvin R
authors.initials: CR
authors.lastname: Maurer
authors.forename: Ryan
authors.initials: R
authors.lastname: Gallivan
authors.forename: Hwan-Jung
authors.initials: HJ
authors.lastname: Roh
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Citardi
mesh_terms: D002102:Cadaver; D006801:Humans; D008953:Models, Anatomic; D008962:Models, Theoretical; D013517:Otorhinolaryngologic Surgical Procedures / Q000295:instrumentation*; D010256:Paranasal Sinuses / Q000601:surgery*; D013238:Stereotaxic Techniques / Q000295:instrumentation*; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*