iDQC MR Imaging with Contrast of Off-resonance Rotating-frame Spin-Lattice Relaxation
Zheng B, Chen Z, Kennedy S, Zhong J
A long-duration, low-power, and off-resonance spin-locking pulse was incorporated into the CRAZED sequence in order to measure the intermolecular double-quantum longitudinal relaxation time in the tilted rotating frame. This modified CRAZED sequence was appended to a fast spin-echo imaging sequence to form images with contrast of the intermolecular double-quantum longitudinal relaxation time in the tilted rotating frame. The results show that both the tilt angle and the effective spin-locking frequency can be used as controllable parameters to manipulate image contrast. The off-resonance spin-locking technique reduces the absorption of rf energy which may be harmful to the patients in clinical applications.