Anatomical correlates for magnetoencephalography: integration with magnetic resonance images.

We have implemented an initial version of software for the integration of magnetic resonance imaging (MRI) and magnetoencephalography (MEG). The package displays MRI images and performs basic image processing. The coordinate systems of the two methods are matched with the help of markers fixed on known head landmarks and a 3D digitiser. The spherical conductor model can be individually fitted to the shape of the brain in the region of interest. The computed source locations can be instantly superimposed on the MRI images during the analysis. Examples of localisation results from a healthy subject and an epileptic child are discussed.