title: Intraoperative visualisation of language fascicles by diffusion tensor imaging-based tractography in glioma surgery.
abstract: BACKGROUND
  For gliomas, the goal of surgery is to maximise the extent of resection (EOR) while minimising the postoperative morbidity. The purpose of this study was to evaluate the benefits of a protocol developed for the surgical management of gliomas located in language areas, where tractography-integrated navigation was used in conjunction with direct electrical stimulations (DES).
  
  
  METHODS
  The authors included ten patients suffering of gliomas located in language areas. The preoperative planning for multimodal navigation was done by integrating anatomical magnetic resonance images and subcortical pathway volumes generated by diffusion tensor imaging. Six white matter fascicles implicated in language functions were reconstructed in each patient, including fibres for phonological processing (i.e. the arcuate fasciculus), fibres for lexical-semantic processing (i.e. the inferior frontooccipital fasciculus, inferior longitudinal fasciculus and uncinate fasciculus), and two premotor fasciculi involved in the preparation of speech movements (the subcallosal medialis fasciculus and cortical fibres originating from the medial and lateral premotor areas). During surgery, language fascicles were identified by direct visualisation on tractography-integrated navigation images and by observing transient language inhibition after subcortical DES. Language deficits were evaluated preoperatively and postoperatively, and compared with the EOR.
  
  
  RESULTS
  Tractography was successfully performed in all patients, preoperatively demonstrating the relationships between the tumours to resect and the language fascicles to preserve from injury. With the use of the tractography-integrated navigation system and intraoperative DES, language functions were preserved in all patients. The mean volumetric resection was 93.0 ± 10.4 % of the preoperative tumour volume, with a gross total resection in 60 % of patients.
  
  
  CONCLUSIONS
  The intraoperative combination of tractography and DES contributed to maximum safe resection of gliomas located in language areas.
authors.affiliation: Neurosurgery Service, Hôpital Nord, Centre Hospitalier Universitaire de Saint-Etienne, Saint-Etienne, France. francoisvassal@wanadoo.fr
authors.forename: François
authors.initials: F
authors.lastname: Vassal
authors.forename: Fabien
authors.initials: F
authors.lastname: Schneider
authors.forename: Anna
authors.initials: A
authors.lastname: Sontheimer
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Lemaire
authors.forename: Christophe
authors.initials: C
authors.lastname: Nuti
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001037:Aphasia / Q000503:physiopathology* / Q000517:prevention & control*; D001111:Arcuate Nucleus of Hypothalamus / Q000503:physiopathology / Q000601:surgery; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000503:physiopathology* / Q000601:surgery*; D002540:Cerebral Cortex / Q000503:physiopathology / Q000601:surgery; D003337:Corpus Callosum / Q000503:physiopathology / Q000601:surgery; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D018303:Ganglioglioma / Q000503:physiopathology / Q000601:surgery; D005909:Glioblastoma / Q000503:physiopathology / Q000601:surgery; D005910:Glioma / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000503:physiopathology / Q000601:surgery; D038361:Neuronavigation / Q000379:methods*; D009837:Oligodendroglioma / Q000503:physiopathology / Q000601:surgery; D011183:Postoperative Complications / Q000503:physiopathology* / Q000517:prevention & control*; D011300:Preoperative Care / Q000379:methods