T1 Fast Acquisition Relaxation Mapping (T1-FARM): Optimized Data Acquisition

A theoretical procedure for estimating the precision of the T1 Fast Acquisition Relaxation Mapping sequence as a function of a number of acquisition parameters has been validated by both simulations and experimental results. These results have clarified the selection of sequence parameters to give optimal accuracy and precision in the R1∗ measurements. There is excellent agreement between theory, simulation, and experiment except for flip angles greater than 9°, at which point slice profile imperfections significantly degrade the precision of the technique. The experimental results indicate that over a range of T1s that would be seen in a bolus tracking experiment (25–1200 ms), T1 Fast Acquisition Relaxation Mapping can be used to obtain 64 × 128 R1∗ maps at a rate of 1 map/s, with a precision of 10% or better.