In Epilepsia open
OBJECTIVE : To identify non-EEG based signals and algorithms for detection of motor and non-motor seizures in people lying in bed during video-EEG (VEEG) monitoring and to test whether these algorithms work in freely moving people during mobile EEG recordings.
METHODS : Data of three groups of adult people with epilepsy (PwE) were analyzed. Group 1 underwent VEEG with additional devices (accelerometry, ECG, electrodermal activity); group 2 underwent VEEG, and group 3 mobile EEG recordings both including one-lead ECG. All seizure types were analyzed. Feature extraction and machine learning techniques were applied to develop seizure detection algorithms. Performance was expressed as sensitivity, precision, F1 score and false-positives per 24 h.
RESULTS : The algorithms were developed in group 1 (35 PwE, 33 seizures) and achieved best results (F1 score 56%, sensitivity 67%, precision 45%, false-positives 0.7/24 h) when ECG features alone were used, with no improvement by including accelerometry and electrodermal activity. In group 2 (97 PwE, 255 seizures) this ECG-based algorithm largely achieved the same performance (F1 score 51%, sensitivity 39%, precision 73%, false-positives 0.4/24 h). In group 3 (30 PwE, 51 seizures), the same ECG-based algorithm failed to meet up with the performance in group 1 and 2 (F1 score 27%, sensitivity 31%, precision 23%, false-positives 1.2/24 h). ECG-based algorithms were also separately trained on data of groups 2 and 3 and tested on the data of the other groups, yielding maximal F1 scores between 8-26%.
SIGNIFICANCE : Our results suggest that algorithms based on ECG features alone can provide clinically meaningful performance for automatic detection of all seizure types. Our study also underscores that the circumstances under which such algorithms were developed, and the selection of the training and test data sets need to be considered and limit the application of such systems to unseen patient groups behaving in different conditions.
Jahanbekam Amirhossein, Baumann Jan, Nass Robert D, Bauckhage Christian, Hill Holger, Elger Christian E, Surges Rainer
ECG, Seizure detection, accelerometry, electrodermal activity, mobile EEG