Ambulatory cassette EEG in absence epilepsy.

Absence epilepsy is associated with bursts of generalized 3 Hz spike-and-wave activity. Even very brief bursts may cause an alteration in the level of consciousness and impaired reaction time. We studied 15 patients, ages 5-16 years, with absence epilepsy using 8 channel ambulatory cassette electroencephalography. All patients demonstrated multiple paroxysms of generalized spike-and-wave discharges, most of which were asymptomatic. Because patients with absence epilepsy may not accurately report seizure frequency, periodic long-term monitoring may be required which is accomplished easily on an outpatient basis with ambulatory cassette electroencephalography.