T1ρ and magnetization transfer experiments on a point-of-care 46 mT MRI system

Contrast mechanisms such as T1ρ and MT are interesting for point-of-care (POC) low field systems, to supplement/augment standard T1- and T2- weighting. However they typically require high B0 homogeneity. Here, we use a high homogeneity Halbach-magnet array POC to perform experiments involving either direct on- or off-resonance pulses, and to calculate T1ρ and MT ratio in tissue-mimicking phantoms. T1ρ showed different white matter (WM)/gray matter (GM) contrast compared to T2. The measured magnetization transfer ratio (MTR) showed higher values in the WM than in the GM.