Cardiac cine magnetic resonance fingerprinting for combined ejection fraction, T₁ and T₂ quantification

Area of Science:

• Magnetic Resonance Imaging
• Cardiovascular Imaging
• Biomedical Engineering

Background:

• Cardiac MRI is essential for assessing left ventricular function and myocardial tissue properties.
• Current methods often require separate acquisitions for functional assessment and T1/T2 mapping, increasing scan time.
• There is a need for integrated, time-efficient MRI techniques for comprehensive cardiac assessment.

Purpose of the Study:

• To introduce and validate cine magnetic resonance fingerprinting (cine-MRF) for simultaneous T1, T2, and ejection fraction (EF) quantification.
• To assess the feasibility and accuracy of cine-MRF in phantom and in vivo cardiac MRI.
• To compare cine-MRF results with established cardiac MRI techniques.

Main Methods:

• Developed a cine-MRF technique using free-running MRF sequences with retrospective ECG-sorting.
• Employed low-rank reconstruction with finite difference sparsity for cardiac phase-resolved imaging.
• Utilized nonrigid registration and dictionary matching for T1 and T2 mapping; derived EF from cine images.

Main Results:

• Cine-MRF accurately quantified EF, showing good agreement with conventional cine images (mean bias -1.0%).
• Myocardial T1 and T2 values obtained with cine-MRF were comparable to ECG-triggered cMRF.
• Significant differences were observed in T1 (longer) and T2 (shorter) values compared to MOLLI and T2-prepared FLASH, respectively.

Conclusions:

• Cine-MRF enables simultaneous quantification of cardiac function (EF) and myocardial T1/T2 relaxation times in a single acquisition.
• This technique has the potential to significantly streamline cardiac MRI protocols.
• Cine-MRF offers a time-efficient solution for comprehensive cardiovascular magnetic resonance assessment.