Incorporating Spatial and Spectral Saturation Modules Into MR Fingerprinting.

Area of Science:

• Medical Imaging
• Physics in Medicine

Background:

• Magnetic Resonance Fingerprinting (MRF) enables quantitative mapping of tissue properties.
• Flow-related artefacts can degrade the accuracy of MRF-based T1 and T2 mapping.
• Existing MRF sequences may require modifications to address specific artefact sources.

Purpose of the Study:

• To introduce and evaluate spatial and chemical saturation techniques for artefact reduction in MRF.
• To assess the impact of these saturation methods on T1 and T2 mapping accuracy.
• To demonstrate the utility of saturation modules in in vivo prostate MRF.

Main Methods:

• Modification of a radial MRF pulse sequence to incorporate spatial and chemical saturation modules.
• Phantom experiments to demonstrate artefact reduction and evaluate T1/T2 map accuracy.
• In vivo prostate MRF on a volunteer, comparing maps with and without saturation.

Main Results:

• Spatial saturation effectively reduced streaking artefacts originating from femoral vessels in prostate MRF.
• T1 mapping accuracy was preserved with saturation, while T2 accuracy remained acceptable for T2 values up to ~100 ms.
• In vivo results showed reduced flow-related artefacts in prostate MRF with saturation modules.

Conclusions:

• Spatial and chemical saturation can be integrated into MRF sequences with minimal impact on T1 accuracy.
• These saturation techniques show promise for reducing flow-related artefacts in applications like prostate MRF.
• Further optimization may be necessary for accurate estimation of long T2 components.