title: Passive real-time identification of speech and motor cortex during an awake craniotomy.
abstract: Precise localization of eloquent cortex is a clinical necessity prior to surgical resections adjacent to speech or motor cortex. In the intraoperative setting, this traditionally requires inducing temporary lesions by direct electrocortical stimulation (DECS). In an attempt to increase efficiency and potentially reduce the amount of necessary stimulation, we used a passive mapping procedure in the setting of an awake craniotomy for tumor in two patients resection. We recorded electrocorticographic (ECoG) signals from exposed cortex while patients performed simple cue-directed motor and speech tasks. SIGFRIED, a procedure for real-time event detection, was used to identify areas of cortical activation by detecting task-related modulations in the ECoG high gamma band. SIGFRIED's real-time output quickly localized motor and speech areas of cortex similar to those identified by DECS. In conclusion, real-time passive identification of cortical function using SIGFRIED may serve as a useful adjunct to cortical stimulation mapping in the intraoperative setting.
authors.affiliation: Department of Neurological Surgery, Washington University School of Medicine, 660 South Euclid, St. Louis, MO 63110, USA.
authors.forename: Jarod
authors.initials: J
authors.lastname: Roland
authors.forename: Peter
authors.initials: P
authors.lastname: Brunner
authors.forename: James
authors.initials: J
authors.lastname: Johnston
authors.forename: Gerwin
authors.initials: G
authors.lastname: Schalk
authors.forename: Eric C
authors.initials: EC
authors.lastname: Leuthardt
mesh_terms: D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000503:physiopathology / Q000601:surgery*; D002540:Cerebral Cortex / Q000503:physiopathology* / Q000601:surgery; D003399:Craniotomy; D004558:Electric Stimulation; D004569:Electroencephalography; D006801:Humans; D009460:Neurologic Examination