Abdominal T1 and T2 mapping at 0.05 Tesla

Motivation: To investigate the abdominal tissue relaxation properties at ultra-low-field (ULF) for sequence optimization to obtain desired contrast. Goal(s): To measure the in vivo T1 and T2 values of various tissues in human abdomen at 0.05 Tesla. Approach: Images at different TRs and TEs were acquired for T1 and T2 mapping through pixel-wise numerical fitting on a shielding-free whole-body 0.05T MRI scanner. Results: Phantom experiments revealed a linear relationship between gadolinium concentration and relaxation rate, demonstrating the reliability of our mapping procedure. Subsequently, T1 and T2 values of liver, muscle, kidney, spleen, and spinal bone marrow were estimated. Impact: The research aims to measure the relaxation properties of liver, muscle, kidney, spleen and spinal bone marrow. These measurements provide valuable information for the design and optimization of MRI sequences to achieve desired image contrast.