Superconducting Probes for Localized MRI/MRS

The long-term objectives of this project are to develop compact low-noise probes for local magnetic- resonance imaging (MRI) and magnetic-resonance spectroscopy (MRS). The Phase Ii goal is to produce probe/preamplifier modules which can be used with existing low-and mid-field MRI machines and which improve the spatial resolution, imaging time, or chemical sensitivity presently obtained. More rapid brain scanning with higher resolution is one expected medical benefit of this project. Another is the sensitive mapping of chemical species other than hydrogen. High-temperature superconducting thin films will be used to obtain the extremely low probe-coil resistances necessary for the low-noise performance. Small probes with localized sensitivity patterns will be used to limit tissue loading effects which degrade the noise performance. The Phase I tasks include: (1) determination of the limitations of present MRI and MRS systems in the study of cerebral function; (2) establishment of performance goals for probes to be made in Phase II; and (3) generation and evaluation of strawman probe designs and prototype devices. In Phase II, probe assemblies, complete with preamps and cryogenic enclosures, will be manufactured and tested.