A method for T1ρ imaging

The spin lattice relaxation time (T1) is dependent on the strength of the polarizing magnetic field. The relaxation at low field strengths provides information from the processes at macromolecular level. However, the decrease of the polarizing magnetic field decreases the signal-to-noise ratio that determines the resolution of magnetic resonance images. In this report we describe a method for T1 rho imaging. The method possesses the relaxation time contrast of low field strengths with signal-to-noise ratio provided by the higher polarizing field. The relaxation time T1 rho is obtained under spin lock conditions. The spin system relaxes toward thermal equilibrium along the locking field. This process is analogous to the spin lattice relaxation at low field strength and characterized by the time constant T1 rho. T1 rho and T1 rho-dispersion may provide new imaging parameters for noninvasive tissue characterization.