| Affiliation: | 1. Division of Neurology, The Hospital for Sick Children, Toronto, ON, Canada;2. Neurosciences and Mental Health, Sickkids Center for Brain and Mental Health, Toronto, ON, Canada;3. Diagnostic Imaging, The Hospital for Sick Children, Toronto, ON, Canada;4. Department of Child Neurology, Seirei Hamamatsu General Hospital, Shizuoka, Japan;5. Department of Pediatrics, Hokkaido University, Graduate School of Medicine, Sapporo, Japan;6. Division of Neurosurgery, The Hospital for Sick Children, Toronto, ON, Canada;7. Center for Advanced Research and Education, Asahikawa Medical University, Asahikawa, Japan;8. Department of Biomedical Physiology and Kinesiology, Simon Fraser University, BC, Canada |
| Abstract: | ObjectiveTo investigate whether advanced dynamic statistical parametric mapping (AdSPM) using magnetoencephalography (MEG) can better localize focal cortical dysplasia at bottom of sulcus (FCDB).MethodsWe analyzed 15 children with diagnosis of FCDB in surgical specimen and 3?T MRI by using MEG. Using AdSPM, we analyzed a ±50?ms epoch relative to each single moving dipole (SMD) and applied summation technique to estimate the source activity. The most active area in AdSPM was defined as the location of AdSPM spike source. We compared spatial congruence between MRI-visible FCDB and (1) dipole cluster in SMD method; and (2) AdSPM spike source.ResultsAdSPM localized FCDB in 12 (80%) of 15 children whereas dipole cluster localized six (40%). AdSPM spike source was concordant within seizure onset zone in nine (82%) of 11 children with intracranial video EEG. Eleven children with resective surgery achieved seizure freedom with follow-up period of 1.9?±?1.5?years. Ten (91%) of them had an AdSPM spike source in the resection area.ConclusionAdSPM can noninvasively and neurophysiologically localize epileptogenic FCDB, whether it overlaps with the dipole cluster or not.SignificanceThis is the first study to localize epileptogenic FCDB using MEG. |
