Electrodes, infusion cannula, and interventional MRI
instrumentation, are constructed with multiple
layers or mixtures of metals or alloys that allow the diamagnetic behavior of some metals to combine with the paramagnetic behavior of others, wherein the devices have a
magnetic susceptibility which is close to that of the material, for example
body tissue, being im The material may thereby be imaged using MRI with
resultant images having greatly reduced
distortion. Optimal
metal composites are determined through mathematical modeling and measurements. In particular,
MR compatible susceptibility-matched electrodes may be used for stimulation and for acquiring
electroencephalography (EEG) data before, during and after MR image and
spectroscopy measurements, with a significant reduction in
distortion of the resulting images and spectra. In accordance with the invention, these electrodes may further be incorporated into micro-
electrode arrays. In addition,
MR compatible susceptibility-matched cannula can implanted before, during and after MR image and
spectroscopy measurements, with a significant reduction in
distortion of the resulting images and spectra.