Dataset Information

Myocardial T₁-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

ABSTRACT:

Background

Myocardial T₁-mapping recently emerged as a promising quantitative method for non-invasive tissue characterization in numerous cardiomyopathies. Commonly performed with an inversion-recovery (IR) magnetization preparation at 1.5T, the application at 3T has gained due to increased quantification precision. Alternatively, saturation-recovery (SR) T₁-mapping has recently been introduced at 1.5T for improved accuracy. Thus, the purpose of this study is to investigate the robustness and precision of SR T₁-mapping at 3T and to establish accurate reference values for native T₁-times and extracellular volume fraction (ECV) of healthy myocardium.

Methods

Balanced Steady-State Free-Precession (bSSFP) Saturation-Pulse Prepared Heart-rate independent Inversion-REcovery (SAPPHIRE) and Saturation-recovery Single-SHot Acquisition (SASHA) T₁-mapping were compared with the Modified Look-Locker inversion recovery (MOLLI) sequence at 3T. Accuracy and precision were studied in phantom. Native and post-contrast T₁-times and regional ECV were determined in 20 healthy subjects (10 men, 27?±?5 years). Subjective image quality, susceptibility artifact rating, in-vivo precision and reproducibility were analyzed.

Results

SR T₁-mapping showed <4 % deviation from the spin-echo reference in phantom in the range of T₁?=?100-2300 ms. The average quality and artifact scores of the T₁-mapping methods were: MOLLI:3.4/3.6, SAPPHIRE:3.1/3.4, SASHA:2.9/3.2; (1: poor - 4: excellent/1: strong - 4: none). SAPPHIRE and SASHA yielded significantly higher T₁-times (SAPPHIRE: 1578?±?42 ms, SASHA: 1523?±?46 ms), in-vivo T₁-time variation (SAPPHIRE: 60.1?±?8.7 ms, SASHA: 70.0?±?9.3 ms) and lower ECV-values (SAPPHIRE: 0.20?±?0.02, SASHA: 0.21?±?0.03) compared with MOLLI (T₁: 1181?±?47 ms, ECV: 0.26?±?0.03, Precision: 53.7?±?8.1 ms). No significant difference was found in the inter-subject variability of T₁-times or ECV-values (T₁: p?=?0.90, ECV: p?=?0.78), the observer agreement (inter: p?>?0.19; intra: p?>?0.09) or consistency (inter: p?>?0.07; intra: p?>?0.17) between the three methods.

Conclusions

Saturation-recovery T₁-mapping at 3T yields higher accuracy, comparable inter-subject, inter- and intra-observer variability and less than 30 % precision-loss compared to MOLLI.

SUBMITTER: Weingartner S

PROVIDER: S-EPMC5114738 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Publications

Myocardial T<sub>1</sub>-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

Weingärtner Sebastian S Meßner Nadja M NM Budjan Johannes J Loßnitzer Dirk D Mattler Uwe U Papavassiliu Theano T Zöllner Frank G FG Schad Lothar R LR

Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance 20161118 1

<h4>Background</h4>Myocardial T<sub>1</sub>-mapping recently emerged as a promising quantitative method for non-invasive tissue characterization in numerous cardiomyopathies. Commonly performed with an inversion-recovery (IR) magnetization preparation at 1.5T, the application at 3T has gained due to increased quantification precision. Alternatively, saturation-recovery (SR) T<sub>1</sub>-mapping has recently been introduced at 1.5T for improved accuracy. Thus, the purpose of this study is to inv ...[more]

PMID: 27855705

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Project description:This study was conducted to improve the precision of arrhythmia-insensitive rapid (AIR) cardiac T1 mapping through pulse sequence optimization and then evaluate the intra-scan repeatability in patients at 3T against investigational modified Look-Locker inversion recovery (MOLLI) T1 mapping. In the first development phase (five human subjects), we implemented and tested centric-pair k-space ordering to suppress image artifacts associated with eddy currents. In the second development phase (15 human subjects), we determined optimal flip angles to reduce the measurement variation in T1 maps. In the validation phase (35 patients), we compared the intra-scan repeatability between investigational MOLLI and optimized AIR. In 23 cardiac planes, conventional centric k-space ordering (3.7%) produced significantly (p < 0.05) more outliers as a fraction of left ventricular cavity area than optimal centric k-space ordering (1.4%). In 15 human subjects, for each of four types of measurement (native myocardial T1 , native blood T1 , post-contrast myocardial T1 , post-contrast blood T1 ), flip angles of 55-65° produced lower measurement variation while producing results that are not significantly different from those produced with the previously used flip angle of 35° (p > 0.89, intra-class correlation coefficient ≥ 0.95 for all four measurement types). Compared with investigational MOLLI (coefficient of repeatability, CR = 40.0, 77.2, 26.5, and 25.9 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 2.0% for extracellular volume (ECV) measurements, respectively), optimized AIR (CR = 54.3, 89.7, 30.5, and 14.7 ms for native myocardial, native blood, post-contrast myocardial, and post-contrast blood T1 , and 1.6% for ECV measurements, respectively) produced similar absolute intra-scan repeatability in all 35 patients in the validation phase. High repeatability is critically important for longitudinal studies, where the goal is to monitor physiologic/pathologic changes, not measurement variation. Optimized AIR cardiac T1 mapping is likely to yield high scan-retest repeatability for pre-clinical and clinical applications.

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Dataset Information

Myocardial T₁-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

Background

Methods

Results

Conclusions

Publications

Myocardial T<sub>1</sub>-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Myocardial T1-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

Background

Methods

Results

Conclusions

Publications

Myocardial T<sub>1</sub>-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Myocardial T₁-mapping at 3T using saturation-recovery: reference values, precision and comparison with MOLLI.