Clinical Neuroscience

[Voltage mapping studies of generalized spike- wave patterns associated with absence seizures]


MARCH 20, 1994

Clinical Neuroscience - 1994;47(03-04)

[In this retrospective study, scalp electric fields of ictal generalized spike-wave discharges were analized by the so-called topographic voltage mapping method. The 17 patients displaying absences (with or without other seizures) belonged to different age groups and diverse epileptic syndromes. Main results: 1. Maps derived at the points of the spike and the wave components belong to different classes. A-type spikes show frontal, P-type spikes show posterior voltage maxima. Also atypical spike (map) configurations exist. 2. A spike maps frequently show a characteristic modification along the GSW pattern. 3. Waves can display bilateral (L) or medial (M) frontal voltage maxima. 4. At least in the time window of several weeks, the dominant spike map pattern and the pattern of the waveform was characteristic to each patient. Configurations of the different spike and wave components show some relation to a limited set of clinical data. The combination of A- spikes with L-waves was found in children who had , typical" absence- epilepsies. On the contrary, irregular spectrum of different spikes and M-waves was found in elder absence patients showing rather unfavorable course of their illness.]


  1. Hajdú-Bihar Megyei Kórház, Idegosztály, Debrecen



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