Magneto‐Encephalographical Analysis of Focal Cortical Heterotopia

Abstract

Focal cortical heterotopia is often associated with intractable seizures. Recent papers have reported that magnetic resonance imaging (MRI) demonstrates cortical heterotopia well compared with other imaging modalities, e.g. computed tomography scan. The authors analyzed the localization of epileptic spike foci of focal cortical heterotopia by 37 channel magnetoencephalography (MEG), and superimposed these dipoles on MRI. The estimated dipoles were observed to be located in a limited area, which corresponded to a focal cortical heterotopia on MRI. The present paper demonstrates that the combination of MEG and MRI is very advantageous for determination of the three dimensional localization of epileptic foci in patients with focal cortical heterotopia.