iDQC MRI weighted by longitudinal relaxation in the rotating frame.
A long-duration, low-power, off-resonance spin-locking pulse was incorporated into the COSY revamped by asymmetric z gradient-echo detection (CRAZED) pulse sequence in order to evaluate the effects of intermolecular double-quantum longitudinal relaxation in the tilted rotating frame (T1rho,DQ(eff)). This modified CRAZED sequence was followed by a standard fast spin-echo imaging sequence to form images with T1rho,DQ(eff)-weighted contrast. Imaging experiments were performed on an agarose-gel phantom and mouse-tail tissue at 600 MHz. Experimental results demonstrated the feasibility of imaging applications based on T1rho,DQ(eff) as a novel contrast mechanism, and showed that iDQC off-resonance longitudinal relaxation in the rotating frame T1rho,DQ(eff) is sensitive to the tilt angle theta and the effective spin-locking field omegae. Imaging based on T1rho,DQ(eff)) has reduced RF power deposition compared to on-resonance spin-locking, which is advantageous for human applications.
Zheng
Bingwen
B
Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surface, Xiamen University, Xiamen, People's Republic of China.
Chen
Zhong
Z
Kennedy
Scott D
SD
Zhong
Jianhui
J
D000818:Animals; D005240:Feasibility Studies; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D019047:Phantoms, Imaging; D013623:Tail / Q000033:anatomy & histology*