Requirement of longitudinal synchrony of epileptiform discharges in the hippocampus for seizure generation: a pilot study.

Object: The goal in this study was to assess the role of longitudinal hippocampal circuits in the generation of interictal and ictal activity in temporal lobe epilepsy (TLE) and to evaluate the effects of multiple hippocampal transections (MHT).

Methods: In 6 patients with TLE, the authors evaluated the synchrony of hippocampal interictal and ictal epileptiform discharges by using a cross-correlation analysis, and the effect of MHT on hippocampal interictal spikes was studied. Five of the 6 patients were studied with depth electrodes, and epilepsy surgery was performed in 4 patients (anterior temporal lobectomy in 1 and MHT in 3).

Statistical analysis of transcallosal propagation of spikes arising from the mesial frontal area.

Objective: To study the connections between bilateral mesial frontal (MF) regions.

Methods: We evaluated synchrony of spikes, recorded by subdural electrodes, arising from bilateral MF regions using cross correlation in MF epilepsy. A seven-year-old boy with intractable daily bilateral asymmetric tonic seizures and a normal MRI was investigated.