This subproject is one of many research subprojects utilizing theresources provided by a Center grant funded by NIH/NCRR. The subproject andinvestigator (PI) may have received primary funding from another NIH source,and thus could be represented in other CRISP entries. The institution listed isfor the Center, which is not necessarily the institution for the investigator.T1rho imaging has shown improved contrast between healthy brain or breast tissues and tumors in mice and humans, tracked the degeneration of the patellar cartilage matrix, is sensitive to posttraumatic cartilage injury and has shown sensitivity to degradation of the nucleus pulposus in studies of degenerative intervertebral disc disease and enabled the indirect detection of metabolic water in vivo.This approach presents some difficulties compared to traditional relaxation contrast techniques, however. Long-duration RF pulses may cause coil damage, the specific absorption rate (SAR) delivered to tissues during a T1rho sequence is high, and both B0 and B1 field imperfections are significant sources of artifacts.To overcome three of these difficulties (coil damage, high SAR, and B1 imperfections), we developed a off-resonance T1rho pulse sequence that implements an off-resonance rotary echo during spin locking. An off-resonance spin lock reduces the spin-lock RF field strength and increases the off-resonance field to achieve the same effective field strength, and thus reduces the SAR and power demands on the RF coil.
Showing the most recent 10 out of 414 publications
