title: High density scalp EEG in frontal lobe epilepsy.
abstract: Localization of seizures in frontal lobe epilepsy using the 10-20 system scalp EEG is often challenging because neocortical seizure can spread rapidly, significant muscle artifact, and the suboptimal spatial resolution for seizure generators involving mesial frontal lobe cortex. Our aim in this study was to determine the value of visual interpretation of 76 channel high density EEG (hdEEG) monitoring (10-10 system) in patients with suspected frontal lobe epilepsy, and to evaluate concordance with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional EEG, and intracranial EEG (iEEG).
  
  
  
  We performed a retrospective cohort study of 14 consecutive patients who underwent hdEEG monitoring for suspected frontal lobe seizures. The gold standard for localization was considered to be iEEG. Concordance of hdEEG findings with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional 10-20 EEG, and iEEG as well as correlation of hdEEG localization with surgical outcome were examined.
  
  
  
  hdEEG localization was concordant with iEEG in 12/14 and was superior to conventional EEG 3/14 (p<0.01) and SISCOM 3/12 (p<0.01). hdEEG correctly lateralized seizure onset in 14/14 cases, compared to 9/14 (p=0.04) cases with conventional EEG. Seven patients underwent surgical resection, of whom five were seizure free.
  
  
  
  hdEEG monitoring should be considered in patients with suspected frontal epilepsy requiring localization of epileptogenic brain. hdEEG may assist in developing a hypothesis for iEEG monitoring and could potentially augment EEG source localization.
authors.affiliation: Department of Neurology, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, United States. Electronic address: Feyissa.Anteneh@mayo.edu.
authors.forename: Anteneh M
authors.initials: AM
authors.lastname: Feyissa
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: Britton.Jeffrey@mayo.edu.
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Britton
authors.affiliation: Departments of Neurological Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: vangompel.jamie@mayo.edu.
authors.forename: Jamie
authors.initials: J
authors.lastname: Van Gompel
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: lagerlund.terrence@mayo.edu.
authors.forename: Terrance L
authors.initials: TL
authors.lastname: Lagerlund
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: eso@mayo.edu.
authors.forename: Elson
authors.initials: E
authors.lastname: So
authors.affiliation: Division of Child and Adolescent Neurology, Mayo Clinic Children's Center, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: WongKisiel.Lily@mayo.edu.
authors.forename: Lilly C
authors.initials: LC
authors.lastname: Wong-Kisiel
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: gcascino@mayo.edu.
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Cascino
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: Brinkmann.Benjamin@mayo.edu.
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Brinkman
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: Nelson.Cindy@mayo.edu.
authors.forename: Cindy L
authors.initials: CL
authors.lastname: Nelson
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: watson.robert16@mayo.edu.
authors.forename: Robert
authors.initials: R
authors.lastname: Watson
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States. Electronic address: Worrell.Gregory@mayo.edu.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Worrell
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D000069279:Drug Resistant Epilepsy / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D004569:Electroencephalography / Q000379:methods; D017034:Epilepsy, Frontal Lobe / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064926:Neurophysiological Monitoring; D011300:Preoperative Care; D012189:Retrospective Studies; D012535:Scalp; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
keywords: Drug resistant epilepsy; Epilepsy surgery; Frontal lobe epilepsy; High density EEG; Midline and parasagittal; SISCOM; Source localization