title: Does interictal spiking change prior to seizures?
abstract: We studied 10 patients with intractable epilepsy being evaluated for epilepsy surgery for preictal changes in spiking. All patients were implanted with intracranial electrodes and underwent continuous EEG/audiovisual monitoring. Interictal spikes were detected and recorded continuously by a dedicated computerized system. Edited spikes were counted during 0-5, 5-10, and 0-60 min epochs before each seizure, during epochs of unvarying state of arousal (awake or sleep stage II). When comparing by repeated measures, 1-way ANOVA, total spiking (in all recording channels) did not differ among the different preictal epochs (0-5, 5-10, 0-60 min) in 45 seizures (F = 0.88, P = 0.40, using the Geisser-Greenhouse adjustment--GGA). Likewise, no significant differences were obtained during those same epochs when comparing spiking originating from the channel of seizure onset in 5 patients with 28 seizures of localized onset (F = 1.19, P = 0.38 using the GGA). Our findings indicate that in patients with intractable epilepsy, no changes in spiking occur in the 5 min prior to seizures, when compared to more distant preictal epochs.
authors.affiliation: Department of Neurology, Yale University School of Medicine, New Haven, CT 06510.
authors.forename: A
authors.initials: A
authors.lastname: Katz
authors.forename: D A
authors.initials: DA
authors.lastname: Marks
authors.forename: G
authors.initials: G
authors.lastname: McCarthy
authors.forename: S S
authors.initials: SS
authors.lastname: Spencer
mesh_terms: D000200:Action Potentials; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001143:Arousal / Q000502:physiology; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D013997:Time Factors