Model-based reconstruction for simultaneous multi-slice mapping using single-shot inversion-recovery radial FLASH

Area of Science:

• Magnetic Resonance Imaging (MRI)
• Medical Physics

Background:

• Quantitative $$ mapping is crucial for various MRI applications.
• Current multi-slice $$ mapping methods can be time-consuming.
• Simultaneous Multi-Slice (SMS) techniques offer accelerated data acquisition.

Purpose of the Study:

• To develop a novel single-shot, multi-slice $$ mapping method.
• To combine Simultaneous Multi-Slice (SMS) excitations with single-shot inversion-recovery (IR) radial fast low-angle shot (FLASH) sequences.
• To implement a nonlinear model-based reconstruction for improved parameter estimation.

Main Methods:

• Extended a single-slice calibrationless model-based reconstruction to SMS.
• Formulated parameter map and coil sensitivity estimation as a single nonlinear inverse problem.
• Applied joint-sparsity constraints for enhanced $$ precision.
• Validated the method in phantoms and human brain/liver scans.

Main Results:

• Achieved accurate and precise multi-slice $$ maps comparable to single-slice references.
• Demonstrated superior performance of SMS over conventional interleaved acquisitions in brain scans.
• Confirmed good accuracy, precision, and repeatability in 6 healthy subjects (brain and abdomen).
• Enabled rapid acquisition of 5 brain slices or 3 abdominal slices in 4 seconds.

Conclusions:

• The proposed IR SMS radial FLASH method enables rapid, high-resolution multi-slice $$ mapping.
• The technique offers good accuracy, precision, and repeatability.
• This advancement has potential for accelerated quantitative MRI.