A method to evaluate the relationship between signal acquisition number and parametric mapping precision in MR fingerprinting

MR Fingerprinting (MRF) is a novel technique to quantify multiple MR parameters simultaneously. A train of pseudorandomized radiofrequency (RF) excitations are used to generate unique signal evolution for different tissues, followed by matching the measured signals to a pre-established dictionary. The signal acquisition number in MRF is related to the signal length. Longer signals and larger dictionaries increase the scan time and computational complexity. However, as the signal acquisition reduces, the mapping precision also changes. Therefore, for designing an efficient MRF sequence, a method to evaluate the precision change is necessary. In this thesis, we propose a mapping variation index to reflect the mapping precision in MRF. Besides, this index can predict the precision change under different signal acquisition numbers before MRF scans and provide a reference for sequence designers to modify the signal acquisition number.