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Network Analysis of Foramen Ovale Electrode Recordings in Drug-resistant Temporal Lobe Epilepsy Patients
Published on: December 18, 2016
Focal epileptiform spikes in conjuction with K-complexes.
James D Geyer1, Paul R Carney, Frank Gilliam
1The Sleep Program, The Clinical Neurophysiology Laboratories, Southern Sleep Specialists, Alabama 35406, USA. geyermd@bellsouth.net
Summary
Focal epileptiform spikes within K-complexes are observed in localization-related epilepsy, though rarely. These discharges may be obscured by K-complexes or sleep spindles during EEG analysis.
Area of Science:
- Neurology
- Clinical Neurophysiology
- Sleep Medicine
Background:
- Epileptiform spikes within K-complexes are documented in generalized epilepsy.
- Previous research indicates frequent association between generalized spikes and K-complexes.
Purpose of the Study:
- To determine the occurrence rate of focal epileptiform spikes within K-complexes in patients with localization-related epilepsy.
- To investigate the potential for K-complexes to obscure focal spikes during electroencephalogram (EEG) interpretation.
Main Methods:
- Review of presurgical/diagnostic long-term video-EEG data from 40 consecutive patients with localization-related epilepsy (temporal and frontal lobe).
- Analysis of sleep samples to quantify K-complexes, spikes, and spikes within K-complexes.
- Comparison with 40 patients experiencing nonepileptic events.
Main Results:
- Focal epileptiform spikes within K-complexes were identified in 15% of right temporal lobe epilepsy, 30% of left temporal lobe epilepsy, and 42% of extratemporal lobe epilepsy patients.
- In most cases, these spikes occurring during K-complexes were infrequent.
- The study confirmed the presence of spikes within K-complexes in localization-related epilepsy.
Conclusions:
- K-complexes can be associated with focal epileptiform discharges in localization-related epilepsy.
- The characteristic features of K-complexes and sleep spindles may mask focal spikes, posing a diagnostic challenge.
- Further investigation into the significance of these findings in epilepsy diagnosis is warranted.
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