title: Computer assisted surgery and endoscopic endonasal approach in 32 procedures.
abstract: Computer aided surgery (CAS) is now routinely introduced in the ENT surgical field especially in endoscopic endonasal surgery.
  
  
  OBJECTIVE
  Using a frameless computer aided surgery for endoscopic endonasal approach (SurgiGATE ORL TM), we tried to evaluate the practical use of such a system, to calculate supplementary installation time of the procedure, to determine the number of matching attempt (referencing) before starting optonavigation and to determine its clinical accuracy.
  
  
  METHODS
  Thirty two patients underwent endoscopic endonasal surgery with the help of CAS; 13 revision cases (2 nasal polyposis, 7 paranasal sinus mucoceles, 4 frontal recess stenosis) and 19 primary cases (16 inflammatory diseases, 3 benign tumor removal). Paired points matching was used as referencing before optonavigation. Clinical accuracy of CAS was calculated at two confidence points during optonavigation and measured in multiples of the pixel size on CT Scan.
  
  
  RESULTS
  Number of matching attempts before starting optonavigation was; mean 1.8 (1-4). Supplementary installation time of the system was; mean 15 minutes (10-40). Clinical accuracy at two confidence points was always between 0.5 mm and 2 mm. (6 < 0.5 mm, 16 < 1 mm, 10 < 2 mm). There was no major complication during surgery neither no side effect due to the use of the CAS except for one case who presented a slight tongue edema due to a wrong position of the dynamic reference base (maxillary splint) during the procedure.
  
  
  CONCLUSIONS
  CAS and optonavigation using the surgiGATE ORL TM is safe and efficient in endoscopic endonasal surgery. The accuracy of the system is sufficient and its use appropriate for primary either revision rhinologic procedures.
authors.affiliation: ENT Department, Université catholique de Louvain, Cliniques Universitaires Saint-Luc, Brussels, Belgium. philippe.rombaux@orlo.ucl.ac.be
authors.forename: Ph
authors.initials: P
authors.lastname: Rombaux
authors.forename: S
authors.initials: S
authors.lastname: Ledeghen
authors.forename: M
authors.initials: M
authors.lastname: Hamoir
authors.forename: B
authors.initials: B
authors.lastname: Bertrand
authors.forename: Ph
authors.initials: P
authors.lastname: Eloy
authors.forename: E
authors.initials: E
authors.lastname: Coche
authors.forename: M
authors.initials: M
authors.lastname: Caversaccio
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004724:Endoscopy / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D009668:Nose Diseases / Q000601:surgery*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome