title: Early experiences with image-guided transoral surgery for the pathologies of the upper cervical spine.
abstract: METHODS
  Technical note.
  
  
  OBJECTIVE
  Three years of convincing experience with cranial neuronavigation suggested the application of the cranial software and registration method for the transoral access to the C1-C2 vertebrae.
  
  
  BACKGROUND
  The C1-C2 vertebrae are located in close vicinity to the cranial base. If the intersegmental movements of the C0-C1/C1-C2 segments are prevented with HALO fixation, the upper cervical spine can be considered as a caudal part of the skull base and included in the extended navigation space of the skull.
  
  
  METHODS
  Three patients were selected for navigation-assisted transoral odontoidectomy. Before surgery the patients were fixed and scanned in a HALO device. The fiducials were attached supraorbitally and to both mastoids, determining a wide registration area and allowing the caudal extension of the navigation space. The BrainLAB VectorVision navigation system was used in cranial mode during the operations.
  
  
  RESULTS
  Neuronavigation and fluoroscopy-controlled transoral surgery were performed with success in all three cases. The registration accuracy was 1.5, 2.7, and 3.1 mm.
  
  
  CONCLUSIONS
  Image guidance during transoral exposure of the upper cervical spine offered excellent three-dimensional guidance on the ventral surface of the craniocervical junction, allowing a safer, more controlled surgery. As the targets of the transoral spinal surgery are fixed bony and ligamentous structures, no shifting occurs and continuous high navigation accuracy can be achieved. The use of the navigation can reduce the significance of the intraoperative fluoroscopy, diminishing the radiograph load of the patient and the operating room team.
authors: National Institute of Neurosurgery, Budapest, Hungary. vererob@mailer.oiti.hu
authors: R
authors: R
authors: Veres
authors: A
authors: A
authors: Bagó
authors: I
authors: I
authors: Fedorcsák
mesh_terms: D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D008875:Middle Aged; D009493:Neurosurgery / Q000295:instrumentation / Q000379:methods*; D013122:Spinal Diseases / Q000000981:diagnostic imaging / Q000601:surgery*; D013238:Stereotaxic Techniques / Q000295:instrumentation; D013523:Surgical Equipment; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome