Dataset Information

Improved reproducibility for myocardial ASL: Impact of physiological and acquisition parameters.

ABSTRACT:

Purpose

To investigate and mitigate the influence of physiological and acquisition-related parameters on myocardial blood flow (MBF) measurements obtained with myocardial Arterial Spin Labeling (myoASL).

Methods

A Flow-sensitive Alternating Inversion Recovery (FAIR) myoASL sequence with bSSFP and spoiled GRE (spGRE) readout is investigated for MBF quantification. Bloch-equation simulations and phantom experiments were performed to evaluate how variations in acquisition flip angle (FA), acquisition matrix size (AMS), heart rate (HR) and blood T1$$ {\mathrm{T}}_1 $$ relaxation time ( T1,B$$ {\mathrm{T}}_{1,B} $$ ) affect quantification of myoASL-MBF. In vivo myoASL-images were acquired in nine healthy subjects. A corrected MBF quantification approach was proposed based on subject-specific T1,B$$ {\mathrm{T}}_{1,B} $$ values and, for spGRE imaging, subtracting an additional saturation-prepared baseline from the original baseline signal.

Results

Simulated and phantom experiments showed a strong dependence on AMS and FA ( R2$$ {R}^2 $$ >0.73), which was eliminated in simulations and alleviated in phantom experiments using the proposed saturation-baseline correction in spGRE. Only a very mild HR dependence ( R2$$ {R}^2 $$ >0.59) was observed which was reduced when calculating MBF with individual T1,B$$ {\mathrm{T}}_{1,B} $$ . For corrected spGRE, in vivo mean global spGRE-MBF ranged from 0.54 to 2.59 mL/g/min and was in agreement with previously reported values. Compared to uncorrected spGRE, the intra-subject variability within a measurement (0.60 mL/g/min), between measurements (0.45 mL/g/min), as well as the inter-subject variability (1.29 mL/g/min) were improved by up to 40% and were comparable with conventional bSSFP.

Conclusion

Our results show that physiological and acquisition-related factors can lead to spurious changes in myoASL-MBF if not accounted for. Using individual T1,B$$ {\mathrm{T}}_{1,B} $$ and a saturation-baseline can reduce these variations in spGRE and improve reproducibility of FAIR-myoASL against acquisition parameters.

SUBMITTER: Bozic-Iven M

PROVIDER: S-EPMC10962577 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Publications

Improved reproducibility for myocardial ASL: Impact of physiological and acquisition parameters.

Božić-Iven Maša M Rapacchi Stanislas S Tao Qian Q Pierce Iain I Thornton George G Nitsche Christian C Treibel Thomas A TA Schad Lothar R LR Weingärtner Sebastian S

Magnetic resonance in medicine 20230905 1

<h4>Purpose</h4>To investigate and mitigate the influence of physiological and acquisition-related parameters on myocardial blood flow (MBF) measurements obtained with myocardial Arterial Spin Labeling (myoASL).<h4>Methods</h4>A Flow-sensitive Alternating Inversion Recovery (FAIR) myoASL sequence with bSSFP and spoiled GRE (spGRE) readout is investigated for MBF quantification. Bloch-equation simulations and phantom experiments were performed to evaluate how variations in acquisition flip angle ...[more]

PMID: 37667643

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Dataset Information

Improved reproducibility for myocardial ASL: Impact of physiological and acquisition parameters.

Purpose

Methods

Results

Conclusion

Publications

Improved reproducibility for myocardial ASL: Impact of physiological and acquisition parameters.

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