title: Frameless stereotactic functional neuronavigation combined with intraoperative magnetic resonance imaging as a strategy in highly eloquent located tumors causing epilepsy.
abstract: BACKGROUND
  Intractable epilepsy due to tumors located in highly eloquent brain regions is often considered surgically inaccessible because of a high risk of postoperative neurological deterioration. Intraoperative MRI and functional navigation contribute to overcome this problem.
  
  
  OBJECTIVE
  To retrospectively investigate the long-term results and impact of functional neuronavigation and 1.5-tesla intraoperative MRI on patients who underwent surgery of tumors associated with epilepsy located close to or within eloquent brain areas.
  
  
  METHODS
  Nineteen patients (9 female, 10 male, mean age 41.4 ± 13.4 years, 11 low-grade and 8 high-grade glial tumors) were evaluated preoperatively using BOLD imaging, diffusion-tensor imaging tractography and magnetoencephalography. Functional data were implemented into neuronavigation in this multimodal approach.
  
  
  RESULTS
  In 14 of 19 patients (74%), complete resection was achieved, and in 5 patients significant tumor volume reduction was accomplished. Eight of 14 (57%) complete resections were achieved only by performing an intraoperative image update. Neurological deterioration was found permanently in 2 patients. After a mean follow-up of 43.8 ± 23.8 months, 15 patients (79%) became seizure free (Engel class Ia).
  
  
  CONCLUSIONS
  Despite the highly eloquent location of tumors causing intractable epilepsy, our multimodal approach led to complete resection in more than two-thirds of patients with an acceptable neurological morbidity and excellent long-term seizure control.
authors.affiliation: Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany.
authors.forename: Bjoern
authors.initials: B
authors.lastname: Sommer
authors.forename: Peter
authors.initials: P
authors.lastname: Grummich
authors.forename: Hajo
authors.initials: H
authors.lastname: Hamer
authors.forename: Ingmar
authors.initials: I
authors.lastname: Bluemcke
authors.forename: Roland
authors.initials: R
authors.lastname: Coras
authors.forename: Michael
authors.initials: M
authors.lastname: Buchfelder
authors.forename: Karl
authors.initials: K
authors.lastname: Roessler
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000150:complications* / Q000473:pathology / Q000601:surgery*; D002540:Cerebral Cortex / Q000473:pathology; D004569:Electroencephalography; D004827:Epilepsy / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007432:Intraoperative Period; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D038361:Neuronavigation / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome