John S. Ebersole

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OBJECTIVES We used a 3-compartment boundary element method (BEM) model from an averaged magnetic resonance image (MRI) data set (Montreal Neurological Institute) in order to provide simple access to realistically shaped volume conductor models for source reconstruction, as compared to individually derived models. The electrode positions were transformed(More)
PURPOSE To determine the area of cortical generators of scalp EEG interictal spikes, such as those in the temporal lobe epilepsy. METHODS We recorded simultaneously 26 channels of scalp EEG with subtemporal supplementary electrodes and 46 to 98 channels of intracranial EEG in 16 surgery candidates with temporal lobe epilepsy. Cerebral discharges with and(More)
SUMMARY Scalp EEG is an essential component of epilepsy presurgical evaluation during the lateralization and localization of epileptogenic focus. Scalp EEG epileptiform discharges may either guide direct surgical intervention or provide necessary information to further localize the epileptic focus with intracranial EEG recording. Despite the importance and(More)
There is a direct relationship between the geometry (location, area, and orientation) of cortex-generating epileptiform discharges and resultant spike or seizure voltage fields at the scalp. Epileptogenic foci have been localized traditionally with EEG by identifying the negative field maximum (e.g., a phase reversal between adjacent bipolar channels).(More)
PURPOSE We wished to determine whether continuous EEG source imaging can predict the location of seizure onset with sublobar accuracy in temporal lobe epilepsy (TLE). METHODS We retrospectively analyzed the earliest scalp ictal rhythms, recorded with 23- to 27-channel EEG, in 40 patients with intractable TLE. A continuous source analysis technique with(More)
OBJECTIVE To determine the relationship between cortical origins of interictal and ictal EEG discharges in patients with temporal lobe epilepsy. METHODS Simultaneous cortical and scalp EEG recordings were obtained from six patients with temporal lobe epilepsy. Subdural electrode contacts active at seizure onset and when scalp ictal rhythms became evident(More)
PURPOSE To determine the cerebral electroencephalography (EEG) substrates of scalp EEG seizure patterns, such as source area and synchrony, and in so doing assess the limitations of scalp seizure recording in the localization of seizure onset zones in patients with temporal lobe epilepsy. METHODS We recorded simultaneously 26 channels of scalp EEG with(More)
Magnetoencephalographic (MEG) dipole source localization is a particularly promising new tool for noninvasive presurgical evaluation of epileptogenic foci. It is potentially more accurate than EEG localization techniques because magnetic fields are not attenuated or distorted by the skull and scalp, which allows cerebral sources to be modeled more simply.(More)
OBJECTIVE To investigate the accuracy and reliability of 3D CT/MRI co-registration technique for the localization of implanted subdural electrodes in the routine epilepsy presurgical evaluation, in so doing assess its usefulness in planning the tailored resection of epileptic focus. METHODS Four external anatomic fiducial makers were used for(More)
PURPOSE To determine the intracranial EEG features responsible for producing the various ictal scalp rhythms, which we previously identified in a new EEG classification for temporal lobe seizures. METHODS In 24 patients, we analyzed simultaneous intracranial and surface ictal EEG recordings (64 total channels) obtained from a combination of intracerebral(More)