Magnetic Resonance Imaging Using SQUIDs

Superconducting Quantum Interference Devices (SQUIDs) are the most sensitive magnetic field detectors in existence. Recent experiments at the University of California, Berkeley, and here at Quantum Magnetics have shown that SQUIDs can be used to detect radiofrequency nuclear magnetic signals. This opens up the possibility of using SQUIDs to do magnetic resonance imaging (MRI), particularly at low fields and frequencies. SQUID detection would make possible a variety of advances including (1) increased image contrast using very low applied fields, (2) enhanced sensitivity for heavy nuclei such as 14N, 13C and 31 P, (3) MRI systems that operate at a wide range of frequencies, and (4) low-cost MRI systems using inexpensive low- field magnets. SQUID MRI systems will be cost effective with conventional low-Tc SQUIDs, and it will be even less expensive as good high-Tc SQUIDs become available. In Phase I, we will detect nuclear magnetic resonance (NMR) signals from samples using a SQUID. It is anticipated that the results will prove that a SQUID MRI system is feasible. Having considerable expertise in NMR and NMR instrumentation and being a world leader in SQUID technology, we are uniquely positioned to develop a SQUID MRI system.