Advanced

AJNR - American Journal of Neuroradiology

This Article Abstract Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Hara, K. Articles by Stufflebeam, S.M. Search for Related Content PubMed PubMed Citation Articles by Hara, K. Articles by Stufflebeam, S.M.

Magnetoencephalographic Mapping of Interictal Spike Propagation: A Technical and Clinical Report

K. Hara^a, F.-H. Lin^a,b, S. Camposano^a, D.M. Foxe^a, P.E. Grant^a, B.F. Bourgeois^c, S.P. Ahlfors^a and S.M. Stufflebeam^a

^a From MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, Mass
^b Institute of Biomedical Engineering, National Taiwan University, Taipei, Republic of China
^c Division of Epilepsy and Clinical Neurophysiology, Children's Hospital, Boston, Mass

View larger version (33K): [in this window] [in a new window]   Fig 1. ECDs for visually detected MEG spikes coregistered with anatomic MR imaging. The dots and lines indicate the locations (green, right frontal region; yellow, left) and orientations of the ECDs, respectively..

View larger version (37K): [in this window] [in a new window]   Fig 2. Recorded MEG and EEG signals for 1 representative spike. In MEG, the latency between the peak signal intensity in the right and left frontal sensors was 21 ms. It was more difficult to characterize the spikes in EEG. The latency between the peak signals in the right frontal MEG sensors and the right frontal bipolar EEG-derivation (FP2-F8) was approximately 12 ms. The EEG channel names follow the International Federation of Clinical Neurophysiology (IFCN) standard..

View larger version (31K): [in this window] [in a new window]   Fig 3. Top: The lateral views of the dSPM obtained by temporally aligning the peak of all left frontal lobe spikes (A) and labeling the peak as time 0 ms. Activity in the right frontal lobe (B) can be seen at 21 ms before the left frontal activity (A) at 0 ms. Bottom: The dSPM obtained by temporally aligning the peaks of all right frontal lobe spikes (C). No preceding left frontal lobe activity was found. The white arrowhead indicates the location of cortical dysplasia lesion..

View larger version (134K): [in this window] [in a new window]   Fig 4. 3T MR imaging shows the location of cortical dysplasia in the right frontal lobe (arrowhead).