Myocardial Approximate Spin-lock Dispersion Mapping using a Simultaneous $T_{2}$ and $T_{RAFF2}$ Mapping at 3T MRI

Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, vol. 2022, pp. 1694–1697

Abstract

Ischemic heart disease (IHD) is one of the leading causes of death worldwide. Myocardial infarction (MI) represents a third of all IHD cases, and cardiac magnetic resonance imaging (MRI) is often used to assess its damage to myocardial viability. Late gadolinium enhancement (LGE) is the current gold standard, but the use of gadolinium-based agents limits the clinical applicability in some patients. Spin-lock (SL) dispersion has recently been proposed as a promising non-contrast biomarker for the assessment of MI. However, at 3T, the required range of SL preparations acquired at different amplitudes suffers from specific absorption rate (SAR) limitations and off-resonance artifacts. Relaxation Along a Fictitious Field (RAFF) is an alternative to SL preparations with lower SAR requirements, while still sampling relaxation in the rotating frame. In this study, a single breath-hold simultaneous$T_{RAFF2}$and$T_{2}$mapping sequence is proposed for SL dispersion mapping at 3T. Excellent reproducibility (coefficient of variations lower than 10%) was achieved in phantom experiments, indicating good intrascan repeatability. The average myocardial$T_{RAFF2}, T_{2}$, and SL dispersion obtained with the proposed sequence$(68.0\pm 10.7$ms,$44.0\pm 4.0$ms, and$0.4\pm 0.2 \times 10^{-4} s^{2}$, respectively) were comparable to the reference methods$(62.7\pm 11.7$ms,$41.2\pm 2.4$ms, and$0.3\pm 0.2\mathrm{x} 10^{-4}s^{2}$, respectively). High visual map quality, free of$B_{0}$and$B_{1}^{+}$related artifacts, for$T_{2}, T_{RAFF2}$, and SL dispersion maps were obtained in phantoms and in vivo, suggesting promise in clinical use at 3T. Clinical relevance — and imaging promises non-contrast assessment of scar and focal fibrosis in a single breath-hold using approximate spin-lock dispersion mapping.

Authors 8

1. João Tourais

   Delft University of Technology

   Affiliation as printed

   Delft University of Technology (TU Delft),Department of Imaging Physics,Delft,Netherlands

   Department of Imaging Physics, Delft University of Technology (TU Delft), Delft, Netherlands

2. Ömer Burak Demirel

   University of Minnesota

   Affiliation as printed

   Department for Electrical and Computer Engineering,Minneapolis,MN,USA

   Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA

   Department for Electrical and Computer Engineering, Minneapolis, MN, USA

3. Qian Tao

   Delft University of Technology

   Affiliation as printed

   Delft University of Technology (TU Delft),Department of Imaging Physics,Delft,Netherlands

   Department of Imaging Physics, Delft University of Technology (TU Delft), Delft, Netherlands

4. Iain Pierce

   University College London

   Affiliation as printed

   Barts Heart Centre and Institute for Cardiovascular Science, University College London,London,United Kingdom

   Barts Heart Centre and Institute for Cardiovascular Science, University College London, London, United Kingdom

5. George D. Thornton

   University College London

   Affiliation as printed

   Barts Heart Centre and Institute for Cardiovascular Science, University College London,London,United Kingdom

   Barts Heart Centre and Institute for Cardiovascular Science, University College London, London, United Kingdom

6. Thomas Alexander Treibel

   University College London · Delft University of Technology

   Affiliation as printed

   Barts Heart Centre and Institute for Cardiovascular Science, University College London,London,United Kingdom

   Barts Heart Centre and Institute for Cardiovascular Science, University College London, London, United Kingdom

   Department of Imaging Physics, Delft University of Technology (TU Delft), Delft, Netherlands

7. Mehmet Akçakaya

   University of Minnesota

   Affiliation as printed

   Department for Electrical and Computer Engineering,Minneapolis,MN,USA

   Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, USA

   Department for Electrical and Computer Engineering, Minneapolis, MN, USA

8. Sebastian Weingärtner Aachen

   Leiden University Medical Center · Holland Particle Therapy Center · Delft University of Technology

   Affiliation as printed

   Delft University of Technology (TU Delft),Department of Imaging Physics,Delft,Netherlands

   Delft University of Technology, Delft, The Netherlands

   Department of Imaging Physics, Delft University of Technology (TU Delft), Delft, Netherlands

   HollandProton Therapy Centre, Delft, The Netherlands

   Leiden University Medical Center (LUMC), Leiden, The Netherlands