Clinical measurements in multiple sclerosis with single channel magnetoencephalography

The authors have been assessing the clinical usefulness of a single channel MEG system, located within a `cheap´ eddy-current shielded room alongside a busy hospital Clinical Neurophysiology department serving a population of 2.7 million people with the emphasis not on the accuracy of resolution of a dipole source but rather on the other known properties of MEG compared with EEG namely the rejection of activity from distant sources, and the absence of the `reference´ problem. The comparison has therefore been between concurrently recorded conventional Evoked Potentials (EP) and magnetic evoked fields (EF)