2021 Volume Annual59 Issue Abstract Pages 354
Background: To analyze High frequency oscillations (HFO) of magnetoencephalography, we have developed gradient magnetic-oscillation topography (GMOT), which projects every sensor vertically onto the brain surface and displays the power for each frequency on the brain surface. Methods: The subjects were 11 patients with intractable epilepsy who underwent focal resection. There were 7 males and 4 females (mean 23.0 years). Postoperative pathological findings were Glioma in 7, Cavernous hemangioma in 2, Hippocampal sclerosis in 1, and Focal cortical dysplasia type II in 1. GMOTs were created to visualize the power of 200-330 Hz. Fast ripples (FR) are defined as power of 800 (fT/m)^2/Hz or higher. The 3-35 Hz waveform was also analyzed by ECD.Results: ECDs clustered near the lesion in 8/11. GMOT visualized FR near the lesion in 9/11.Conclusion: The results of HFO analysis by GMOT showed almost the same as the ECD method.
