| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 3042993 | Clinical Neurophysiology | 2015 | 8 Pages |
•For the first time a connectivity-based analysis of MEG data is tested for epileptogenic focus localization in patients with neocortical epilepsy.•MEG recordings from five patients with medically-intractable focal epilepsy undergoing presurgical evaluation for resection of candidate epileptic focus were analyzed.•Proposed algorithm can localize the epileptogenic focus accurately even in patients with normal MRI (MRI-negative) or patients without interictal abnormalities on scalp EEG (EEG-negative) or MEG (MEG-negative).
ObjectiveTo investigate whether epileptogenic focus localization is possible based on resting state connectivity analysis of magnetoencephalographic (MEG) data.MethodsA multivariate autoregressive (MVAR) model was constructed using the sensor space data and was projected to the source space using lead field and inverse matrix. The generalized partial directed coherence was estimated from the MVAR model in the source space. The dipole with the maximum information inflow was hypothesized to be within the epileptogenic focus.ResultsApplying the focus localization algorithm (FLA) to the interictal MEG recordings from five patients with neocortical epilepsy, who underwent presurgical evaluation for the identification of epileptogenic focus, we were able to correctly localize the focus, on the basis of maximum interictal information inflow in the presence or absence of interictal epileptic spikes in the data, with three out of five patients undergoing resective surgery and being seizure free since.ConclusionOur preliminary results suggest that accurate localization of the epileptogenic focus may be accomplished using noninvasive spontaneous “resting-state” recordings of relatively brief duration and without the need to capture definite interictal and/or ictal abnormalities.SignificanceEpileptogenic focus localization is possible through connectivity analysis of resting state MEG data irrespective of the presence/absence of spikes.
