Parametric maps of water molecular dynamics in a multi-compartment
phantom containing three agar tubes prepared with 1%, 2% and
3% w/v. Good contrast can be seen between tubes in T1ρ,
T2ρ, τc,b, τex and Pb.
Chemical shift exchange frequency δωex is
approximately 1 ppm in all tubes, showing, as expected, no dependency on agar
concentration. Importantly, the map of water bound fraction Pb is
able to distinguish a difference of 1% agar concentration. Goodness of
fit is indicated by the coefficient of determination R2 showed in the
bottom figures.