Adiabatic spin-lock preparations for myocardial T2ρ mapping at 3T.

Motivation: T2ρ may provide complementary information between T1ρ and T2, but high sensitivity to field inhomogeneities has prevented its application in cardiac MRI. Goal(s): We evaluated adiabatic T2ρ preparations for human myocardium mapping at 3T. Approach: To obtain T2ρ preparations, adiabatic half-passage pulses were added before and after pairs of hyperbolic secant pulses. T2ρ mapping was tested and compared with adiabatic T1ρ and T2 maps in phantoms and 5 healthy subjects. Results: T2ρ maps yielded similar values to T2, with improved repeatability and resilience to B0 and B1+ field inhomogeneities in phantom, and better precision and reproducibility in vivo, complementing T1ρ. Impact: Adiabatic T2ρ preparations enable robust in vivo myocardial T2ρ mapping at 3T, potentially enabling the use of an alternative rotating-frame relaxation contrast mechanism for cardiac tissue characterization at high field strengths.