Toward Microtesla MRI of Hyperpolarized Carbon-13 for Real-Time Metabolic Imaging

Vadim S. Zotev¹, Tuba Owens¹, Igor M. Savukov¹, Andrei N. Matlashov¹, John J. Gomez¹, Michelle A. Espy¹

Hyperpolarization of C-13 has enabled real-time metabolic imaging of C-13 labeled substances with unprecedented signal-to-noise levels. Because hyperpolarization is performed outside an MRI scanner, high magnetic fields of conventional MRI offer little advantage in terms of C-13 polarization. We propose an ultimate low-field MRI scanner for imaging hyperpolarized C-13. It uses only microtesla-range magnetic fields and employs SQUID sensors to measure MRI signals. We present the first images acquired by SQUID-based microtesla MRI with dynamic nuclear polarization. We also report the first NMR spectra of C-13 at microtesla fields. Our results demonstrate feasibility and potential of the proposed imaging approach.