Dataset Information

Accelerated free-breathing 3D T1? cardiovascular magnetic resonance using multicoil compressed sensing.

ABSTRACT:

Background

Endogenous contrast T1? cardiovascular magnetic resonance (CMR) can detect scar or infiltrative fibrosis in patients with ischemic or non-ischemic cardiomyopathy. Existing 2D T1? techniques have limited spatial coverage or require multiple breath-holds. The purpose of this project was to develop an accelerated, free-breathing 3D T1? mapping sequence with whole left ventricle coverage using a multicoil, compressed sensing (CS) reconstruction technique for rapid reconstruction of undersampled k-space data.

Methods

We developed a cardiac- and respiratory-gated, free-breathing 3D T1? sequence and acquired data using a variable-density k-space sampling pattern (A?=?3). The effect of the transient magnetization trajectory, incomplete recovery of magnetization between T1?-preparations (heart rate dependence), and k-space sampling pattern on T1? relaxation time error and edge blurring was analyzed using Bloch simulations for normal and chronically infarcted myocardium. Sequence accuracy and repeatability was evaluated using MnCl₂ phantoms with different T1? relaxation times and compared to 2D measurements. We further assessed accuracy and repeatability in healthy subjects and compared these results to 2D breath-held measurements.

Results

The error in T1? due to incomplete recovery of magnetization between T1?-preparations was T1?_healthy =?6.1% and T1?_infarct =?10.8% at 60?bpm and T1?_healthy =?13.2% and T1?_infarct =?19.6% at 90?bpm. At a heart rate of 60?bpm, error from the combined effects of readout-dependent magnetization transients, k-space undersampling and reordering was T1?_healthy =?12.6% and T1?_infarct =?5.8%. CS reconstructions had improved edge sharpness (blur metric?=?0.15) compared to inverse Fourier transform reconstructions (blur metric?=?0.48). There was strong agreement between the mean T1? estimated from the 2D and accelerated 3D data (R² =?0.99; P 2 phantoms. The mean R1? estimated from the accelerated 3D sequence was highly correlated with MnCl₂ concentration (R² =?0.99; P?2D =?6.4% and COV_3D =?7.1%).

Conclusions

This is the first report of an accelerated, free-breathing 3D T1? mapping of the left ventricle. This technique may improve non-contrast myocardial tissue characterization in patients with heart disease in a scan time appropriate for patients.

SUBMITTER: Kamesh Iyer S

PROVIDER: S-EPMC6327532 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Publications

Accelerated free-breathing 3D T1ρ cardiovascular magnetic resonance using multicoil compressed sensing.

Kamesh Iyer Srikant S Moon Brianna B Hwuang Eileen E Han Yuchi Y Solomon Michael M Litt Harold H Witschey Walter R WR

Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance 20190110 1

<h4>Background</h4>Endogenous contrast T1ρ cardiovascular magnetic resonance (CMR) can detect scar or infiltrative fibrosis in patients with ischemic or non-ischemic cardiomyopathy. Existing 2D T1ρ techniques have limited spatial coverage or require multiple breath-holds. The purpose of this project was to develop an accelerated, free-breathing 3D T1ρ mapping sequence with whole left ventricle coverage using a multicoil, compressed sensing (CS) reconstruction technique for rapid reconstruction o ...[more]

PMID: 30626437

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