Prolonged EEG Monitoring in Epilepsies

The development of prolonged EEG monitoring technique was a response to the demand to extend the time window of the routine 20-min laboratory EEG. Prolonged EEG monitoring increases the ability to detect interictal epileptiform discharges and enables to “capture” clinical seizures in patients with relatively frequent epileptic or other attacks of questionable nature.

The first continuous monitoring method was described in cardiology by Holter in 1961. The development of the more complicated multichannel portable EEG monitoring technique with flexible parametric applications followed only in the 1970s, using first miniature head amplifiers. In 1982, Ives introduced a 16-channel ambulatory EEG that utilized signal multiplexing, but recorded only discrete samples. In 1983, a cassette tape system was developed with off-head amplifiers and continuous eight-channel recording. From that time, in the past 2 decades, computer technology has enabled portable recording of up to 36 channels with...