MRI-superconductivity in the marketplace

Magnets for medical Magnetic Resonance Imaging (MRI) represent the first large scale commercial application of superconductivity. These devices have been in production in the U.S., the U.K., and Europe for several years and the basic designs have stabilized. Since the magnets operate at relatively low fields (generally < 2 Tesla), they have not required advances in basic superconducting materials or magnet technology. Progress has come rather in the areas of cryogen consumption, field homogeneity, transportability, shielding, reliability, and the user interface. This paper reviews the currently available devices and the areas presently under development.