title: Neuronavigation without rigid pin fixation of the head in left frontotemporal tumor surgery with intraoperative speech mapping.
abstract: OBJECTIVE
  Intraoperative speech mapping has evolved into the "gold standard" for neurosurgical removal of lesions near the language cortex. The integration of neuronavigation into a multimodal protocol can improve the reliability of this type of operation, but most systems require rigid fixation of the patient's head throughout the operation. This article describes and evaluates a new noninvasively attached sensor-based reference tool, which can replace rigid pin fixation of the patient's head during awake craniotomies.
  
  
  METHODS
  The attachment technique and the resulting application accuracy were investigated under clinical conditions in 13 patients undergoing awake craniotomy with intraoperative mapping of cortical language sites.
  
  
  RESULTS
  Spatial information was used for updating the image guidance by continuously adjusting the image planes relative to the position of the patient's head. The mean registration error achieved with this technique was 1.53 +/- 0.51 mm (fiducial registration error +/- standard deviation). The system's median application accuracy between dura opening and closure ranged from 0.83 to 1.85 mm (position error).
  
  
  CONCLUSIONS
  The use of a reference sensor can replace uncomfortable pin fixation of the patient's head during navigation-supported awake craniotomies. Application accuracy is not affected by repositioning of the patient or by unavoidable head movements. Thus, this technique enables full exploitation of the benefits of navigation in a multimodal operative protocol without the need to rigidly fix the patient's head.
authors.affiliation: Department of Neurosurgery, Charité-Campus Benjamin Franklin, Berlin, Germany. olaf.suess@charite.de
authors.forename: Olaf
authors.initials: O
authors.lastname: Suess
authors.forename: Thomas
authors.initials: T
authors.lastname: Picht
authors.forename: Bjoern
authors.initials: B
authors.lastname: Kuehn
authors.forename: Sven
authors.initials: S
authors.lastname: Mularski
authors.forename: Mario
authors.initials: M
authors.lastname: Brock
authors.forename: Theodoros
authors.initials: T
authors.lastname: Kombos
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping / Q000295:instrumentation* / Q000379:methods; D001932:Brain Neoplasms / Q000601:surgery*; D003399:Craniotomy / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000601:surgery*; D006801:Humans; D021621:Imaging, Three-Dimensional; D007806:Language Disorders / Q000209:etiology / Q000517:prevention & control; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation* / Q000379:methods; D038361:Neuronavigation / Q000295:instrumentation* / Q000379:methods; D013702:Temporal Lobe / Q000473:pathology / Q000601:surgery*; D014705:Verbal Behavior; D014851:Wakefulness