title: Reliability of seizure semiology in patients with 2 seizure foci.
abstract: OBJECTIVE
  To determine whether seizure semiology is reliable in localizing and distinguishing seizures at 2 independent brain foci in the same patient.
  
  
  METHODS
  Two masked reviewers localized seizures from 2 foci by their clinical semiology and intracranial electroencephalograms (EEGs).
  
  
  METHODS
  Epilepsy monitoring unit of referral comprehensive epilepsy program.
  
  
  METHODS
  Seventeen consecutive patients (51 seizures) with sufficient video and intracranial EEG data were identified by reviewing medical records of 366 patients older than 10 years.
  
  
  METHODS
  The primary outcome measures were interobserver agreement between the 2 masked reviewers; the proportion of seizures localized by semiology; the proportion of localized seizures concordant with intracranial EEG localization; and comparison between concordant and nonconcordant seizures in latency of intracranial EEG seizure spread.
  
  
  RESULTS
  Interobserver agreement was 41% (κ score, 0.16). Only 30 of 51 seizures (59%) were localized by seizure semiology. The focus localized by semiology was concordant with the location of intracranial EEG seizure onset in 16 of 30 seizures (53%). No significant difference was observed between concordant and nonconcordant seizures in relation to the speed with which the EEG discharge spread from the location of seizure onset to another lobar region (P = .09, Wilcoxon rank sum test).
  
  
  CONCLUSIONS
  Clinical seizure semiology is not as useful as intracranial EEG in localizing seizure onset in patients with dual seizure foci.
authors.affiliation: Department of Neurology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Rathke
authors.forename: Barbara
authors.initials: B
authors.lastname: Schäuble
authors.forename: A James
authors.initials: AJ
authors.lastname: Fessler
authors.forename: Elson L
authors.initials: EL
authors.lastname: So
mesh_terms: D001931:Brain Mapping / Q000379:methods; D002540:Cerebral Cortex / Q000503:physiopathology*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors / Q000517:prevention & control*; D004569:Electroencephalography / Q000379:methods* / Q000592:standards*; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D009069:Movement Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D009460:Neurologic Examination / Q000379:methods / Q000592:standards; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D016037:Single-Blind Method; D014741:Video Recording / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data