Utility of EMG Channels in Pediatric EMU
Abstract number :
1.149
Submission category :
3. Neurophysiology / 3A. Video EEG Epilepsy-Monitoring
Year :
2022
Submission ID :
2204433
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:24 AM
Authors :
Wadih Baajour, MD – University of Texas Southwestern Medical Center, Dallas , Texas; Katherine Wojcicki, DO – Clinical Epilepsy Fellow, Pediatric Neurology, University of Texas Southwestern Medical Center; Andrea Grundy, R.EEGT/CLTM – Senior EEG technologist, Pediatrics, Childrens Health Dallas; Deepa Sirsi, MD – Associate Professor, Pediatric Neurology, University of Texas Southwestern Medical Center
Rationale: Precise diagnosis and identification of epileptic events by using electromyography (EMG) channels during VEEG recordings in epilepsy monitoring unit (EMU).
Methods: We included 2 EMG channels (neck and right deltoid) to all admitted children in our EMU, in addition to the standard EEG 10-20 electrodes. Epileptic events were classified according to EMG tone changes and duration of the events.
1. A myoclonic jerk was associated with an increase in EMG tone for less than 200 msec.
2. A spasm was associated with an increase in EMG tone for 0.2 to 2 seconds.
3. A tonic seizure was associated with an increase in EMG tone for 2 to 10 seconds.
4. An atonic seizure was associated with an absence/ decrease in EMG tone for 1 to 2 seconds.
Results: EMG helped in identification and classification of seizures in 64% of reported jerks/spasms, 83% of children with events of drop attacks and 75% of children with stiffening episodes. The EMG was also helpful to identify subtle ictal events (subtle myoclonic jerks and spasm clusters) (Table 1).
Image 1 demonstrates an example of a drop attack which was classified as a tonic seizure based on increase in tone noted on EMG channel.
Conclusions: Classifying seizure type using clinical and EEG data alone can be difficult and can lead to misclassification. The use of the EMG channels during vEEG monitoring is an easy and useful tool that can help in distinguishing myoclonic, spasm, tonic, and atonic seizures. It can also help in detection and quantification of epileptic myoclonus and spasms. Knowing the specific seizure type is important because they have different clinical implications.
Funding: None
Neurophysiology