Use of pattern recognition for unaliasing simultaneously acquired slices in simultaneous multislice MR fingerprinting

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Biomedical Engineering
• Medical Physics

Background:

• Magnetic Resonance Fingerprinting (MRF) enables quantitative tissue mapping.
• Accelerating MRF acquisition is crucial for clinical applicability.
• Simultaneous multislice (SMS) imaging offers potential for acceleration.

Purpose of the Study:

• To accelerate MRF acquisition using a simultaneous multislice (SMS) method.
• To develop a multiband radiofrequency (RF) pulse for exciting multiple slices concurrently.
• To validate the accuracy of the accelerated MRF method for T1 and T2 quantification.

Main Methods:

• Designed a multiband RF pulse to excite two slices with orthogonal signals.
• Matched undersampled MRF signals to dictionaries for T1 and T2 mapping.
• Validated quantitative results against gold-standard spin echo methods in phantoms.
• Compared in vivo human brain T1 and T2 maps with conventional MRF-FISP.

Main Results:

• The SMS-MRF-FISP method accurately quantified relaxation properties in phantoms, comparable to spin echo methods.
• In vivo brain T1 and T2 values obtained with SMS-MRF-FISP matched conventional MRF-FISP results.
• Accurate T1 and T2 quantification was achieved at a multiband acceleration factor of two with a single-channel coil.

Conclusions:

• Simultaneous multislice MRF-FISP accelerates acquisition while maintaining quantitative accuracy.
• The method is effective even with a single-channel receive coil.
• Further acceleration is possible by integrating parallel imaging or iterative reconstruction techniques.