Optimization of spin-lock preparation pulses for B1 and B0 insensitive cardiac T1ρ mapping

Cardiac T1ρ mapping is a promising technique for assessment of myocardial fibrosis without exogenous contrast agent. However, its wide application is hindered by the sensitivity of T1ρ preparation to B1 and B0 inhomogeneities. In this study, the state-of-the-art constant spin-lock methods including the composite and adiabatic excitation continuous-wave spin-lock methods were investigated using numerical simulations to assess their robustness to field inhomogeneities, and validated in phantoms and a preliminary subject. Two T1ρ preparation modules were found to generate superior T1ρ mapping quality in the presences of B0 and B1 inhomogeneities, indicating the potential of clinical application of cardiac T1ρ MRI.