title: Accuracy of seizure detection using abbreviated EEG during polysomnography.
abstract: The purpose of this study was to determine the validity of abbreviated EEG montages for seizure detection during polysomnography. Three electroencephalographers reviewed files containing seizures or nonepileptic events using 8- and 18-channel montages. Files were rated as to whether they contained seizures and assigned a "probability of seizure" score from 0% to 100% reflecting the confidence that it was a seizure. Readers then localized seizures as temporal, frontal, parieto-occipital, or nonlocalized and provided a probability of correct localization with 0% to 100% confidence. Data were analyzed using the Adjusted McNemar Test method of Obochuwski. The probability of seizure score was measured using the receiver operating characteristic curve. Observed agreement was 78% and 84% for 8- and 18-channel montages, respectively. Readers were better able to distinguish seizures from nonepileptic events using the 18-channel montage (P = 0.004). Seizures localized to the temporal and parieto-occipital regions were more likely to be correctly identified and localized. Readers were able to correctly localize 27% and 49% of seizures using the 8- and 18-channel montages, respectively (P < 0.001). Abbreviated EEG montages are inadequate in the differentiation of seizures and nonepileptic events arising from sleep during polysomnography. This seems to be particularly true in frontal lobe epilepsy.
authors.affiliation: Department of Neurology, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA. foldvan@ccf.org
authors.forename: Nancy
authors.initials: N
authors.lastname: Foldvary-Schaefer
authors.forename: Jose
authors.initials: J
authors.lastname: De Ocampo
authors.forename: Edward
authors.initials: E
authors.lastname: Mascha
authors.forename: Richard
authors.initials: R
authors.lastname: Burgess
authors.forename: Dudley
authors.initials: D
authors.lastname: Dinner
authors.forename: Harold
authors.initials: H
authors.lastname: Morris
mesh_terms: D019540:Area Under Curve; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D004569:Electroencephalography; D006801:Humans; D017286:Polysomnography; D012640:Seizures / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology*; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D012890:Sleep / Q000502:physiology*