Detection of short-lasting and ictal spike-and-wave discharges in around-the-ears EEG recordings in children with absence epilepsy.

PURPOSE: Long-term ambulatory EEG recordings can improve the monitoring of absence epilepsy in children, but signal quality and increased review workload are a concern. We evaluated the feasibility of around-the-ears EEG arrays (cEEGrids) to capture 3-Hz short-lasting and ictal spike-and-wave discharges and assessed the performance of automated detection software in cEEGrids data. We compared patterns of bilateral synchronisation between short-lasting and ictal spike-and-wave discharges. METHODS: We recruited children with suspected generalised epilepsy undergoing routine video-EEG monitoring and performed simultaneous cEEGrids recordings. We used ASSYST software to detect short-lasting 3-Hz spike-and-wave discharges (1-3 s) and ictal spike-and-wave discharges in the cEEGrids data. We assessed data quality and sensitivity of cEEGrids for spike-and-wave discharges in routine EEG. We determined the sensitivity and false detection rate for automated spike-and-wave discharge detection in cEEGrids data. We compared bihemispheric synchrony across the onset of short-lasting and ictal spike-and-wave discharges using the mean phase coherence in the 2-4 Hz frequency band. RESULTS: We included nine children with absence epilepsy (median age = 11 y, range 8-15 y, nine females) and recorded 4 h and 27 min of cEEGrids data. The recordings from seven participants were suitable for quantitative analysis, containing 82 spike-and-wave discharges. The cEEGrids captured 58 % of all spike-and-wave discharges (median individual sensitivity: 100 %, range: 47-100 %). ASSYST detected 82 % of all spike-and-wave discharges (median: 100 %, range: 41-100 %) with a false detection rate of 48/h (median: 6/h, range: 0-154/h). The mean phase coherence significantly increased during short-lasting and ictal spike-and-wave discharges in the 500-ms pre-onset to 1-s post-onset interval. CONCLUSIONS: cEEGrids are of variable quality for monitoring spike-and-wave discharges in children with absence epilepsy. ASSYST could facilitate the detection of short-lasting and ictal spike-and-wave discharges with clear periodic structures but with low specificity. A similar course of bihemispheric synchrony between short-lasting and ictal spike-and-wave discharges indicates that cortico-thalamic driving may be relevant for both types of spike-and-wave discharges.

Benefits of additional cardiologic examination in patients admitted for differential diagnosis to the Epilepsy Center Bethel.

Additional cardiologic examination for syncope is used for patients admitted for diagnostic reasons in the Epilepsy Center Bethel if, after epileptologic examination, the etiology of seizures remains uncertain and a cardiologic etiology is suspected. Therefore, we retrospectively analyzed all patient data from the diagnostic department between 02/2011 and 07/2015 to evaluate the benefits to patients of additional cardiologic examination for syncope. 78 out of 1567 patients underwent additional cardiologic examination for syncope. Syncope was confirmed in 50 cases (25 neurocardiogenic, 4 orthostatic hypotension, 6 rhythmogenic, 2 others, 13 unknown). The previous diagnosis of epilepsy made before admission to the Epilepsy Center Bethel was rejected in 25 out of 30 cases. Loop recorders were implanted in 26 patients. In 8 out of 26 cases the loop recorder helped to provide a definite diagnosis of a cardiac arrhythmia (n = 6) or to rule out a cardiac cause (n = 2). In conclusion, patients benefit from a close cooperation between epileptology and cardiology.