Improvements in R1 mapping at ultra-low field using denoised and motion corrected field-cycling MRI in brain and head

Motivation: Field-cycling MRI makes it possible to characterise the clinical potential of endogenous spin-lattice R1 image contrast that arises at ultra-low-magnetic field strengths. Goal(s): Our goal was to examine the extent translated motion correction and denoising approaches improve the utility of R1 mapping performed at ultra-low field. Approach: : Improvements in sensitivity to differences in R1 between tissue types and fitting accuracy were determined across brain and head tissues. Results: Improvements in sensitivity and goodness of fit were observed. Significant difference in R1 values between regions of white matter and confluent small vessel disease were observed between 0.2 - 200 mT. Impact: The improvement in sensitivity of R1 mapping using translated motion correction and denoising approaches provides new opportunities to assess the clinical potential of new endogenous image contrast mechanism at ultra-low field strengths.