title: [The timing of crisis and day-night distribution of paroxysmal EEG activities: a study on 197 epileptic patients].
abstract: The purpose of the present study was to determine whether paroxysmal EEG activity (PA) occurs randomly over time and whether seizures arise at time of maximum PA. 204 ambulatory recordings (A/EEG) in 197 adult epileptic outpatients have been were included. The patients' seizures were grouped according to ILAE classification: Simple partial seizures; complex partial seizures (CPS), isolated or secondarily generalized; idiopathic generalized seizures: epilepsy with myoclonic absences, generalized tonic-clonic seizures (GTCS) on awakening, GTCS with photo-sensitivity; undetermined epilepsies: "grand mal morpheique", epilepsies with generalized PA without photosensitivity or with All recordings were performed with a 8-channel 24 h cassette recorder system (Medilog 9,000). The video play-back speed used was 20 times the recording speed to allow good detection, characterization and localization of PA. Counting was accomplished by visual analysis. No PA during A/EEG was noted in 24.5 p. 100 of all cases. A diurnal distribution in wakefulness was found in 59 p. 100 of idiopathic generalized epilepsies, PA usually occurring on awakening whatever the specific time of day; in 27 p. 100 of CPS and 20 p. 100 of undetermined epilepsies, with peak PA occurrence at late morning and 6 pm. During resting-state and afternoon-naps, PA occurrence was mainly seen in CPS. PA occurring only in overnight sleep was observed in 17 p. 100 of CPS and 20 p. 100 of undetermined epilepsies. PA distribution pattern in both CPS and undetermined epilepsies suggests an ultradian rhythm (time-dependent). On the other hand, PA pattern in idiopathic generalized epilepsies support the hypothesis of a circadian rhythm linked to sleep/wake--or light/dark--cycle (state-dependent).
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002940:Circadian Rhythm; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000503:physiopathology*; D004827:Epilepsy / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D012890:Sleep; D014851:Wakefulness
vernacular_title: Horaires des crises et répartition nycthémérale des activités EEG paroxystiques: étude chez 197 épileptiques.