Changes in background electroencephalographic activity in benign childhood epilepsy with centrotemporal spikes after oxcarbazepine treatment: a standardized low-resolution brain electromagnetic tomography (sLORETA) study.

BACKGROUND: Several neuroimaging studies have reported neurophysiological alterations in patients with benign childhood epilepsy with centrotemporal spikes (BCECTS). However, reported outcomes have been inconsistent, and the progression of these changes in the brain remains unresolved. Moreover, background electroencephalography (EEG) in cases of BCECTS has not been performed often. METHODS: We investigated background EEG activity changes after six months of oxcarbazepine treatment to better understand the neurophysiological alterations and progression that occur in BCECTS. In 18 children with BCECTS, non-parametric statistical analyses using standardized low resolution brain electromagnetic tomography (sLORETA) were performed to compare the current density distribution of four frequency bands (delta, theta, alpha, and beta) between untreated and treated conditions. RESULTS: Background EEG activity for the delta frequency band was significantly decreased in the fronto-temporal and limbic regions of the left hemisphere after oxcarbazepine treatment (threshold log-F-ratio = ±2.729, P < 0.01). The maximum current density difference was found in the parahippocampal gyrus of the left limbic lobe (Montreal Neurological Institute coordinate [x, y, z = 25, - 20, - 10], Brodmann area 28) (log-F-ratio = 3.081, P < 0.01). CONCLUSIONS: Our results indicate the involvement of the fronto-temporal and limbic cortices in BCECTS, and limbic lobe involvement, including the parahippocampal gyrus, was noted. In addition to evidence of the involvement of the fronto-temporal and limbic cortices in BCECTS, this study also found that an antiepileptic drug could reduce the delta frequency activity of the background EEG in these regions.

Quantitative EEG Analysis in Atypical Rolandic Epilepsies of Childhood / 대한간질학회지

PURPOSE: Benign childhood epilepsy with centrotemporal spikes (BCECT) or benign rolandic epilepsy (BRE) is not always benign in clinical or neuroimaging features. Recent studies have reported atypical forms of rolandic epilepsy with abnormal neurologic and/or neuroimaging findings, sometimes, also with poor seizure control. We investigated whether there are any differences in linear and nonlinear EEG analysis in typical and atypical rolandic epilepsies of childhood. METHODS: Ten patients with typical BRE group and seven patients with atypical BRE group were included in this study. We selected artifact-free 10-second epochs from 19 electrodes of 10-20 international EEG system from each patient. The power spectrum was calculated in delta, theta, alpha, beta, and gamma frequency ranges. The fractal dimension was analyzed as a nonlinear EEG analysis. We analyzed both EEGs with interictal spikes and without focal slowing or epileptiform activities. RESULTS: The spectral EEG analysis showed a significant increase of absolute and relative power of delta with decrease of alpha bands in atypical BRE group compared to typical group. There was no statistical difference in fractal dimension between the two groups. CONCLUSION: Atypical BRE group showed enhanced delta and decreased alpha power, suggesting a cortical dysfunction in this group with poor clinical outcome.