Nocturnal frontal lobe epilepsy: Intracerebral recordings of paroxysmal motor attacks with increasing complexity

Purposes: To show the results of the investigation conducted with intracerebral electrodes in a patient with drug-resistant nocturnal frontal lobe epilepsy, characterized by sleep-related paroxysmal motor attacks of increasing complexity ranging from simple and brief stereotyped motor events to paroxysmal arousals and major attacks. Methods: The patient was studied with long-term video-stereo-electroencephalographic monitoring by means of stereotactically implanted intracerebral electrodes. Results: Video-stereo-electroencephalography demonstrated that minor events and paroxysmal arousals, as well as major attacks, were correlated with a discharge in the right supplementary motor area and central cingulate gyrus. The increasing complexity of these sleep-related ictal motor behaviors reflected a different pattern of discharge, with a progressive spread to other frontal and extrafrontal areas in the fully developed attacks. Surgical resection of the right supplementary motor area and central cingulate gyrus was performed. In the 5 years since the operation, the patient has remained completely seizure free. Conclusion: This study clearly demonstrates the ictal origin of minor events in nocturnal frontal lobe epilepsy. The increasing complexity of the motor behaviors from minor to major attacks reflects different duration, amplitude, and spread of the epileptic discharge.