Quantitative analysis of surface electromyography during epileptic and nonepileptic convulsive seizures
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Quantitative analysis of surface electromyography during epileptic and nonepileptic convulsive seizures. / Beniczky, Sándor; Conradsen, Isa; Moldovan, Mihai; Jennum, Poul; Fabricius, Martin; Benedek, Krisztina; Andersen, Noémi; Hjalgrim, Helle; Wolf, Peter.
In: Epilepsia, Vol. 55, No. 7, 07.2014, p. 1128-1134.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Quantitative analysis of surface electromyography during epileptic and nonepileptic convulsive seizures
AU - Beniczky, Sándor
AU - Conradsen, Isa
AU - Moldovan, Mihai
AU - Jennum, Poul
AU - Fabricius, Martin
AU - Benedek, Krisztina
AU - Andersen, Noémi
AU - Hjalgrim, Helle
AU - Wolf, Peter
N1 - Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.
PY - 2014/7
Y1 - 2014/7
N2 - OBJECTIVE: To investigate the characteristics of sustained muscle activation during convulsive epileptic and psychogenic nonepileptic seizures (PNES), as compared to voluntary muscle activation. The main goal was to find surface electromyography (EMG) features that can distinguish between convulsive epileptic seizures and convulsive PNES.METHODS: In this case-control study, surface EMG was recorded from the deltoid muscles during long-term video-electroencephalography (EEG) monitoring in 25 patients and in 21 healthy controls. A total of 46 clinical episodes were recorded: 28 generalized tonic-clonic seizures (GTCS) from 14 patients with epilepsy, and 18 convulsive PNES from 12 patients (one patient had both GTCS and PNES). The healthy controls were simulating GTCS. To quantitatively characterize the signals we calculated the following parameters: root mean square (RMS) of the amplitude, median frequency (MF), coherence, and duration of the seizures, of the clonic EMG discharges, and of the silent periods between the cloni. Based on wavelet analysis, we distinguished between a low-frequency component (LF 2-8 Hz) and a high-frequency component (HF 64-256 Hz).RESULTS: Duration of the seizure, and separation between the tonic and the clonic phases distinguished at group-level but not at individual level between convulsive PNES and GTCS. RMS, temporal dynamics of the HF/LF ratio, and the evolution of the silent periods differentiated between epileptic and nonepileptic convulsive seizures at the individual level. A combination between HF/LF ratio and RMS separated all PNES from the GTCS. A blinded review of the EMG features distinguished correctly between GTCS and convulsive PNES in all cases. The HF/LF ratio and the RMS of the PNES were smaller compared to the simulated seizures.SIGNIFICANCE: In addition to providing insight into the mechanism of muscle activation during convulsive PNES, these results have diagnostic significance, at the individual level. Surface EMG features can accurately distinguish convulsive epileptic from nonepileptic psychogenic seizures, even in PNES cases without rhythmic clonic movements.
AB - OBJECTIVE: To investigate the characteristics of sustained muscle activation during convulsive epileptic and psychogenic nonepileptic seizures (PNES), as compared to voluntary muscle activation. The main goal was to find surface electromyography (EMG) features that can distinguish between convulsive epileptic seizures and convulsive PNES.METHODS: In this case-control study, surface EMG was recorded from the deltoid muscles during long-term video-electroencephalography (EEG) monitoring in 25 patients and in 21 healthy controls. A total of 46 clinical episodes were recorded: 28 generalized tonic-clonic seizures (GTCS) from 14 patients with epilepsy, and 18 convulsive PNES from 12 patients (one patient had both GTCS and PNES). The healthy controls were simulating GTCS. To quantitatively characterize the signals we calculated the following parameters: root mean square (RMS) of the amplitude, median frequency (MF), coherence, and duration of the seizures, of the clonic EMG discharges, and of the silent periods between the cloni. Based on wavelet analysis, we distinguished between a low-frequency component (LF 2-8 Hz) and a high-frequency component (HF 64-256 Hz).RESULTS: Duration of the seizure, and separation between the tonic and the clonic phases distinguished at group-level but not at individual level between convulsive PNES and GTCS. RMS, temporal dynamics of the HF/LF ratio, and the evolution of the silent periods differentiated between epileptic and nonepileptic convulsive seizures at the individual level. A combination between HF/LF ratio and RMS separated all PNES from the GTCS. A blinded review of the EMG features distinguished correctly between GTCS and convulsive PNES in all cases. The HF/LF ratio and the RMS of the PNES were smaller compared to the simulated seizures.SIGNIFICANCE: In addition to providing insight into the mechanism of muscle activation during convulsive PNES, these results have diagnostic significance, at the individual level. Surface EMG features can accurately distinguish convulsive epileptic from nonepileptic psychogenic seizures, even in PNES cases without rhythmic clonic movements.
KW - Adolescent
KW - Adult
KW - Body Surface Potential Mapping
KW - Case-Control Studies
KW - Child
KW - Diagnosis, Differential
KW - Electroencephalography
KW - Electromyography
KW - Epilepsy
KW - Female
KW - Humans
KW - Male
KW - Middle Aged
KW - Seizures
KW - Single-Blind Method
KW - Young Adult
U2 - 10.1111/epi.12669
DO - 10.1111/epi.12669
M3 - Journal article
C2 - 24889069
VL - 55
SP - 1128
EP - 1134
JO - Epilepsia
JF - Epilepsia
SN - 0013-9580
IS - 7
ER -
ID: 138309758