Guidelines for Long-Term Monitoring for Epilepsy

Long-term monitoring for epilepsy (LTME) refers to the simultaneous recording of EEG and clinical behavior over extended periods of time to evaluate patients with paroxysmal disturbances of cerebral function. LTME is used when it is important to correlate clinical behavior with EEG phenomena. EEG recordings of long duration may be useful in a variety of situations in which patients have intermittent disturbances that are difficult to record during routine EEG sessions. However, as defined here, LTME is limited to patients with epileptic seizure disorders or suspected epileptic seizure disorders. These guidelines do not pertain to extended EEG monitoring used in a critical care, intraoperative, or sleep analysis setting. 

Although LTME can, in general, be considered to be longer than routine EEG, the duration varies depending on the indications for monitoring and the frequency of seizure occurrence. Because the intermittent abnormalities of interest may occur infrequently and unpredictably, the time necessary to document the presence of epileptiform transients or to record seizures cannot always be predetermined and may range from hours to weeks. Diagnostic efficacy requires the ability to record continuously until sufficient data are obtained. Consequently, “long-term monitoring” refers more to the capability for recording over long periods of time than to the actual duration of the recording. The term “monitoring” does not imply real-time analysis of the data. 

Developments in digital technology have enhanced the ability to acquire, store, and review data in LTME to such a degree that digital systems are now the industry standard. These guidelines will therefore focus on these systems. It is expected that further advances in digital technology will make it necessary to review these standards on a regular basis.