Feasibility of boosting SNR using cooled RF receive coils for low field human brain imaging at 72mT

Motivation: Cooled coils could provide an boost SNR for portable low field MRI as an alternative to increasing the field strength using larger, heavier magnets. Goal(s): Test whether cooling RF receive coils with liquid nitrogen could provide an appreciable boost to signal-to-noise ratio (SNR) on low-field portable MRI scanners, where noise is dominated by copper losses in the coil. Approach: A 3.04 MHz multi-turn surface coil was cooled to ~77K using liquid nitrogen and performance was assessed using bench Q measurements and imaging data. Results: The unloaded Q increases from 220 at 293K to 541 at 77K. SNR for the cooled coil increased 4.15x. Impact: Liquid nitrogen cooled radiofrequency receive coils could improve image quality for low field portable MRI scanners, broadening the impact of these systems.