Acceleration of Spin-Locked 3D GRE Acquisitions for Rapid T1rho Mapping of the Brain

Casey P. Johnson¹, Daniel R. Thedens¹, Vincent A. Magnotta¹, ²

Acceleration methods are assessed for 3D T1rho mapping of the brain. It is demonstrated that substantial reductions in acquisition time (R>5) can be realized while largely retaining T1rho contrast detectability. The use of only two vs. four spin-lock times is also shown to be highly effective, particularly when combined with high degrees of undersampling, yielding net sampling reductions of R>10. The methods demonstrated in this work may greatly improve the utility of 3D T1rho mapping of brain diseases such as Alzheimers and Parkinsons while also enabling state-based dynamic imaging studies such as investigations of stimulus-induced T1rho-sensitive pH fluctuations.