Related Experiment Videos
Ambulatory EEG recordings in epileptic and nonepileptic children
M J Aminoff1, D S Goodin, B O Berg
1Department of Neurology, University of California Medical Center, San Francisco 94143.
Insights
Ambulatory EEG in children helps diagnose epilepsy by detecting electrographic changes during seizures. However, the absence of EEG changes during an event does not rule out pseudoseizures if clinically diagnosed.
Area of Science:
- Pediatric Neurology
- Clinical Neurophysiology
Background:
- Epilepsy diagnosis in children can be challenging, especially differentiating epileptic seizures from non-epileptic events.
- Ambulatory electroencephalography (EEG) is a tool used to record brain activity over extended periods.
Purpose of the Study:
- To evaluate the utility of 24-hour ambulatory EEG in differentiating epileptic seizures from non-epileptic episodic disturbances in children.
- To assess the diagnostic significance of ictal electrographic changes during recorded events.
Main Methods:
- Cassette-recorded 24-hour ambulatory EEG was performed on children with clinically suspected epileptic seizures and those with non-epileptic spells.
- Clinical events during the recording period were correlated with EEG findings.
Main Results:
- In epileptic children, 24-hour ambulatory EEG captured events with appropriate electrographic accompaniments in a majority of cases.
- In children with clinically non-epileptic spells, recorded events showed no accompanying electrographic changes.
- Absence of ictal EEG changes during an event did not exclude a clinical diagnosis of epilepsy but supported a diagnosis of pseudoseizures when clinically indicated.
Conclusions:
- The primary role of ambulatory EEG in this cohort was to exclude non-epileptic events by identifying electrographic seizure activity.
- While not definitive in isolation, the absence of ictal EEG changes supports a clinical diagnosis of pseudoseizures.
- Further research is needed to establish the long-term role of ambulatory EEG in unclear cases of episodic cerebral dysfunction.
Abstract:
We examined the cassette-recorded 24-hour ambulatory EEG findings in children who had either clinically definite seizures or episodic behavioral disturbances not regarded as epileptic on clinical grounds. Among 40 epileptic patients, 22 had one or more attacks during the 24-hour recording session. In 15 of these patients all clinical attacks had appropriate ictal electrographic accompaniments; in another 6 some (but not all) attacks did so. Among 55 children with nonepileptic spells clinically, the 24-hour recording was uninterpretable for technical reasons in one, and in 30 it provided no relevant information because there were no recorded clinical or electrographic attacks. In the remaining 24 patients, one or more clinical attacks were captured, and in no instance was there any accompanying electrographic change. Our findings indicate that the absence of ictal EEG changes during attacks cannot be used in isolation to make a diagnosis of pseudoseizures, but support such a diagnosis made on clinical grounds. The more important role of the ambulatory EEG is to exclude a diagnosis of nonepileptic attacks by demonstrating electrographic seizure activity accompanying typical clinical attacks. Whether the technique will have a useful role in the evaluation of patients when the nature of an episodic disturbance of cerebral function is unclear clinically remains to be established, but will require long-term follow-up to validate any conclusions reached by the electrophysiologic technique.