title: Neuronavigation in surgery of intracranial and spinal tumors.
abstract: OBJECTIVE
  To demonstrate the new possibilities and advantages of neuronavigation in the surgery of intracranial and spinal tumors, based on patient populations treated in our hospital.
  
  
  METHODS
  An infrared navigation system with integrated microscope guidance was used for frameless intracranial neuronavigation. The biopsies of intracranial tumors were carried out using a frame-based stereotactic technique. Intracranial navigation was, in part, combined with the use of an intraoperative CT scanner and a three-dimensional ultrasound system for data acquisition, correction of brain shifts, and intraoperative quality control. The navigation was also supported by presurgical brain mapping with magnetic source imaging. Navigation in spinal surgery was exclusively performed using an infrared navigation system in combination with an intraoperative CT scanner.
  
  
  RESULTS
  The stereotactic tumor biopsies (n = 57) were carried out with an accuracy of 91.4% as compared with the histological diagnosis. The work flow of stereotactic procedures could be increased by using the intraoperative CT scanner. Fifty-seven patients with intracranial tumors were treated with the aid of neuronavigation between July 1997 and December 1999. These patients showed an improvement from 80% to 86% on the Karnofsky index 8 weeks postoperatively. The majority of intracranial cases were primary brain tumors (n = 30) and metastases (n = 13) in functionally important areas of the brain. In four patients, a significant brain shift was observed during neuronavigation, and could be corrected by an image update using either the intraoperative CT scanner (n = 2) or the three-dimensional ultrasound system (n = 2). The presurgical brain mapping with magnetoencephalography was shown to be reliable in the sensory cortex (n = 25). Eleven patients with a thoracic or lumbar tumor were treated by open surgery or stabilization, using a combination of spinal neuronavigation and the intraoperative CT scanner. Two patients with spinal tumors underwent navigated biopsies. Neither of them showed a reduction in the clinical stage, but the Karnofsky index improved from 63% up to 72% 8 weeks postoperatively.
  
  
  CONCLUSIONS
  Neuronavigation allows very precise intracranial and spinal surgery. The problem of brain shift during the navigation procedures has been solved by intraoperative image acquisition. The use of neuronavigation was shown to improve the postoperative quality of life of patients suffering from brain and spinal tumors.
authors.affiliation: Department of Neurological Surgery, University Hospital, Jena College of Medicine, Friedrich-Schiller-University Jena, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Haberland
authors.forename: K
authors.initials: K
authors.lastname: Ebmeier
authors.forename: R
authors.initials: R
authors.lastname: Hliscs
authors.forename: J P
authors.initials: JP
authors.lastname: Grnewald
authors.forename: J
authors.initials: J
authors.lastname: Silbermann
authors.forename: J
authors.initials: J
authors.lastname: Steenbeck
authors.forename: H
authors.initials: H
authors.lastname: Nowak
authors.forename: R
authors.initials: R
authors.lastname: Kalff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001931:Brain Mapping; D001932:Brain Neoplasms / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D006801:Humans; D017567:Karnofsky Performance Status; D008279:Magnetic Resonance Imaging; D008297:Male; D008866:Microsurgery / Q000295:instrumentation / Q000379:methods; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000295:instrumentation / Q000379:methods*; D013125:Spinal Neoplasms / Q000175:diagnosis / Q000601:surgery*; D013238:Stereotaxic Techniques / Q000295:instrumentation; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography