Generalized Fast Electroencephalographical Activity in Typical Absence Seizures.
Abstract number :
2.111
Submission category :
Year :
2000
Submission ID :
514
Source :
www.aesnet.org
Presentation date :
12/2/2000 12:00:00 AM
Published date :
Dec 1, 2000, 06:00 AM
Authors :
Laura Mff Guilhoto, Carmen L Jorge, Elza Mt Yacubian, Hosp das Clinicas da FMUSP, Sao Paulo, Brazil.
RATIONALE: To describe clinical and electroencephalographical characteristics of 4 adult patients with typical absence seizures that presented ictal generalized fast electroencephalographical activity (10-20Hz). METHODS: We studied by video-EEG 4 adult patients that presented typical absence seizures as defined by ILAE (1981) and ictal fast electroencephalographical activity characterized by generalized rhythmic discharges 10-20Hz associated to spike-wave complexes (SWC), all with normal brain magnetic resonance imaging studies. The patients were followed for a mean time of 7 years and 4 months (range 1 year 4 months to 15 years). RESULTS: Four male patients with ages ranging from 28 to 40 years, presented typical absence and generalized tonic clonic (GTC) seizures, with mean age of onset 7 to 14 years (mean 8 years and 9 months) and 3 to 15 years (mean 11 years and 3 months), respectively. Two patients had previous absence status episodes and all presented refractory epileptic seizures. Perinatal abnormality (prolonged labor) was present in one patient and familial history for epilepsy in another. Pyknolepsy was reported by two patients and in the remaining two, less than 10 seizures a day were observed. Thirty-eight seizures were recorded, with a mean duration of 18.16 sec (range 5.1 to 43.3 sec). Blinking and eye deviation were observed in 19/38 and 7/38 seizures, respectively. Interictal EEG showed normal background activity, generalized irregular SWC, at times with focal accentuation and exacerbation during sleep. None of these patients had photosensitivity. Ictal EEG presented SWC (mean frequency 3.59 Hz) in 4 patients and polyspike wave discharges in 3, associated with fast rhythmic 10-20 Hz activity with a mean duration of 20.74 sec (range 6.9 to 49.72 sec). CONCLUSIONS: Adult patients with typical absence seizures may present fast electroencephalographic activity associated to SWC, which in these cases were linked to the presence of GTC seizures and refractoriness to antiepileptic drugs. Supported by CNPq.