Accelerated magnetic resonance fingerprinting using soft-weighted key-hole (MRF-SOHO)

作者：Cruz Gastao^*; Schneider Torben; Bruijnen Tom; Gaspar Andreia S; Botnar Rene A M; Prieto Claudia

来源：PLos One, 2018, 13(8): e0201808.

DOI：10.1371/journal.pone.0201808

Object
To develop a novel approach for highly accelerated Magnetic Resonance Fingerprinting (MRF) acquisition.
Materials and methods
The proposed method combines parallel imaging, soft-gating and key-hole approaches to highly accelerate MRF acquisition. Slowly varying flip angles (FA), commonly used during MRF acquisition, lead to a smooth change in the signal contrast of consecutive time-point images. This assumption enables sharing of high frequency data between different time points, similar to what is done in some dynamic MR imaging methods such as key-hole. The proposed approach exploits this information using a SOft-weighted key-HOle (MRF-SOHO) reconstruction to achieve high acceleration factors and/or increased resolution without compromising image quality or increasing scan time. MRF-SOHO was validated on a standard T-1/T-2 phantom and in in-vivo brain acquisitions reconstructing T-1, T-2 and proton density parametric maps.
Results
Accelerated MRF-SOHO using less data per time-point and less time-point images enabled a considerable reduction in scan time (up to 4.6x), while obtaining similar T-1 and T-2 accuracy and precision when compared to zero-filled MRF reconstruction. For the same number of spokes and time-points, the proposed method yielded an enhanced performance in quantifying parameters than the zero-filled MRF reconstruction, which was verified with 2, 1 and 0.7 (sub-millimetre) resolutions.
Conclusion
The proposed MRF-SOHO enabled a 4.6x scan time reduction for an in-plane spatial resolution of 2x2 mm(2) when compared to zero-filled MRF and enabled sub-millimetric (0.7x0.7 mm(2)) resolution MRF.

• 出版日期2018-8-9