Magnetic Resonance Fingerprinting

Why it matters

Combining relaxation and diffusion measurements can provide complementary information about liver tissue. Acquiring them together is challenging: motion during diffusion encoding can cause signal loss and unreliable measurements.

Contribution

DiffPrep optimizes motion-compensated gradient waveforms for diffusion-preparation modules. The open-source Julia implementation makes the waveform optimization reproducible and provides the gradients used in our liver MR fingerprinting study.

Combined with peripheral pulse triggering and a breath-held acquisition, these preparations enable co-registered T1, T2, and apparent diffusion coefficient (ADC) maps in approximately 16 seconds. The method was evaluated in phantoms and healthy volunteers; evaluation in patients remains future work.

Diffusion-prepared MRF at 0.55T

The low-field feasibility study combines radial bSSFP readouts with inversion recovery, T2 preparation, and optimized diffusion-preparation pulses over 16 heartbeats. Simultaneous T1, T2, and ADC mapping was validated in phantoms against spin-echo references at 0.55T.

Related cardiac T1/T2 MRF at 0.55T

The cardiac studies presented at ISMRM and SCMR 2024 investigate T1 and T2 mapping without diffusion preparation or motion-compensated diffusion gradients. Radial bSSFP acquisitions over 16 heartbeats were evaluated in phantoms and healthy volunteers. These studies establish low-field cardiac MRF feasibility; they are distinct from the diffusion-prepared approach above.