A Composite Spin-Lock Pulse For &[Delta]B0 + B1 Insensitive T 1&[rho] Measurement
Daniel G, Gore J, Gatenby C, Avison M, Zhao Y, zeng h
Significant artifacts arise in T1r-weighted imaging from B1 and B0 inhomogeneities. While composite spin-locking preparatory pulses that can correct the artifacts from B1 inhomogeneities have been described, they do not correct artifacts arising from B0 inhomogeneities. These B0 artifacts severely limit the accuracy of T1r relaxation time measurements, especially at lower spin-locking field in high B0 field systems. A new composite spin-locking pulse, which is self-compensating for both B1 and B0 inhomogeneities was proposed. Experimentally obtained T1r weighted images and numerical simulations confirmed that the new pulse greatly reduces the artifacts from B0 inhomogeneities.