Characterization of cortical activity in juvenile myoclonic epilepsy by gradient magnetic field topography

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K16916
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 51030:Pathophysiologic neuroscience-related
• Research Institution: Hiroshima University
• Principal Investigator: Kagawa Kota 広島大学, 病院(医), 助教 (40726981)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: generalized epilepsy / Magnetoencephalography

Outline of Final Research Achievements

Objective: gradient magnetic field topography (GMFT) illustrates the magnetic field gradients of epileptic spikes on a volume-rendered brain surface. The purpose is to characterize cortical activation in juvenile myoclonic epilepsy.
Methods: we examined interictal spikes in 10 patients. We defined the hemisphere where an activation initially appeared as the “preceding hemisphere”. We localized the foci where activations arose and evaluated their spatiotemporal changes. Results: the localization of activation in the preceding hemisphere was frontal in 18 activities (28%), parietal in 10 (15%), and frontal/parietal in 33 (51%), and in the contralateral hemisphere it was frontal in 14 (32%), parietal in 6 (14%), and frontal/parietal in 19 (43%). The median interhemispheric time difference was 7 ms (range: 0-20). Conclusions: activations are localized within the bilateral frontal and parietal regions. Activations arose serially from foci with small time differences.

Free Research Field

てんかん外科

Academic Significance and Societal Importance of the Research Achievements

本研究結果から、若年ミオクロニーてんかんにおけるてんかん放電発生には両側前頭葉、頭頂葉を含む局所的なネットワークが関与することが示唆された。若年ミオクロニーてんかんを代表とする特発性全般てんかんか、焦点性てんかんの二次性全般化か識別が困難な症例が存在するが、本研究成果により今後正しい診断が得られるようになることが期待できる。また、本研究成果は今後薬剤抵抗性全般てんかんの病態探索を行う上でも有用と考えられる。