Dataset Information

3D myocardial T₁ mapping using saturation recovery.

ABSTRACT:

Purpose

To propose a 3D quantitative high-resolution T₁ mapping technique, called 3D SASHA (saturation-recovery single-shot acquisition), which combines a saturation recovery pulse with 1D-navigator-based-respiratory motion compensation to acquire the whole volume of the heart in free breathing. The sequence was tested and validated both in a T₁ phantom and in healthy subjects.

Materials and methods

The 3D SASHA method was implemented on a 1.5T scanner. A diaphragmatic navigator was used to allow free-breathing acquisition and the images were acquired with a resolution of 1.4 × 1.4 × 8 mm³ . For assessment of accuracy and precision the sequence was compared with the reference gold-standard inversion-recovery spin echo (IRSE) pulse sequence in a T₁ phantom, while for the in vivo studies (10 healthy volunteers) 3D SASHA was compared with the clinically used 2D MOLLI (3-3-5) and 2D SASHA protocols.

Results

There was good agreement between the T₁ values measured in a T₁ phantom with 3D SASHA and the reference IRSE pulse sequences (1111.6 ± 31 msec vs. 1123.6 ± 8 msec, P = 0.9947). Mean and standard deviation of the myocardial T₁ values in healthy subjects measured with 2D MOLLI, 2D SASHA, and 3D SASHA sequences were 881 ± 40 msec, 1181.3 ± 32 msec, and 1153.6 ± 28 msec respectively.

Conclusion

The proposed 3D SASHA sequence allows for high-resolution free-breathing whole-heart T₁ -mapping with T₁ values in good agreement with the 2D SASHA and improved precision.

Level of evidence

2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:218-227.

SUBMITTER: Nordio G

PROVIDER: S-EPMC5518207 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

3D myocardial T<sub>1</sub> mapping using saturation recovery.

Nordio Giovanna G Henningsson Markus M Chiribiri Amedeo A Villa Adriana D M ADM Schneider Torben T Botnar René M RM Botnar René M RM

Journal of magnetic resonance imaging : JMRI 20170202 1

<h4>Purpose</h4>To propose a 3D quantitative high-resolution T<sub>1</sub> mapping technique, called 3D SASHA (saturation-recovery single-shot acquisition), which combines a saturation recovery pulse with 1D-navigator-based-respiratory motion compensation to acquire the whole volume of the heart in free breathing. The sequence was tested and validated both in a T<sub>1</sub> phantom and in healthy subjects.<h4>Materials and methods</h4>The 3D SASHA method was implemented on a 1.5T scanner. A dia ...[more]

PMID: 28152227

Similar Datasets

Project description:BackgroundMyocardial 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.MethodsBalanced 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.ResultsSR 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.ConclusionsSaturation-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.

Project description:BackgroundMyocardial T1 mapping shows promise for assessment of cardiomyopathies. Most myocardial T1 mapping techniques, such as modified Look-Locker inversion recovery (MOLLI), generate one T1 map per breath-held acquisition (9-17 heartbeats), which prolongs multislice protocols and may be unsuitable for patients with breath-holding difficulties.PurposeTo develop and characterize novel shortened inversion recovery based T1 mapping schemes of 2-5 heartbeats.Study typeProspective.Population/phantomNumerical simulations, agarose/NiCl2 phantom, 16 healthy volunteers, and 24 patients.Field strength/sequence1.5T/MOLLI.AssessmentAll shortened T1 mapping schemes were characterized and compared with a conventional MOLLI scheme (5-(3)-3) in terms of accuracy, precision, spatial variability, and repeatability.Statistical testsKruskal-Wallis, Wilcoxon rank sum tests, analysis of variance, Student's t-tests, Bland-Altman analysis, and Pearson correlation analysis.ResultsAll shortened schemes provided limited T1 time variations (≤2% for T1 times ≤1200 msec) and limited penalty of precision (by a factor of ~1.4-1.5) when compared with MOLLI in numerical simulations. In phantom, differences between all schemes in terms of accuracy, spatial variability, and repeatability did not reach statistical significance (P > 0.71). In healthy volunteers, there were no statistically significant differences between all schemes in terms of native T1 times and repeatability for myocardium (P = 0.21 and P = 0.87, respectively) and blood (P = 0.79 and P = 0.41, respectively). All shortened schemes led to a limited increase of spatial variability for native myocardial T1 mapping with respect to MOLLI (by a factor of 1.2) (P < 0.0001). In both healthy volunteers and patients, the two-heartbeat scheme and MOLLI led to highly linearly correlated T1 times (correlation coefficients ≥0.83).Data conclusionThe proposed two-heartbeat T1 mapping scheme yields a 5-fold acceleration compared with MOLLI, with highly linearly correlated T1 times, no significant difference of repeatability, and limited spatial variability penalty at 1.5T. This approach may enable myocardial T1 mapping in patients with severe breath-holding difficulties and reduce the examination time of multislice protocols.Level of evidence1 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2019;50:641-654.

Dataset Information

3D myocardial T₁ mapping using saturation recovery.

Purpose

Materials and methods

Results

Conclusion

Level of evidence

Publications

3D myocardial T<sub>1</sub> mapping using saturation recovery.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

3D myocardial T1 mapping using saturation recovery.

Purpose

Materials and methods

Results

Conclusion

Level of evidence

Publications

3D myocardial T<sub>1</sub> mapping using saturation recovery.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

3D myocardial T₁ mapping using saturation recovery.