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Preparation of 2‐amino‐2‐hydroxymethyl‐1,3‐propanediol ( TRIS ) pHT buffers in synthetic seawater
- Award ID(s):
- 1657799
- PAR ID:
- 10220626
- Date Published:
- Journal Name:
- Limnology and Oceanography: Methods
- Volume:
- 18
- Issue:
- 9
- ISSN:
- 1541-5856
- Page Range / eLocation ID:
- 504 to 515
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT Background0.55T systems offer unique advantages and may support expanded access to cardiac MRI. PurposeTo assess the feasibility of 0.55T cardiac MR Fingerprinting (MRF), leveraging a deep image prior reconstruction to mitigate noise. Study TypePhantom and prospective in vivo assessment. PopulationISMRM/NIST MRI system phantom and 18 healthy subjects (11 female; ages 28 ± 8 years). Field Strength and SequencesMRF, modified Look‐Locker inversion recovery (MOLLI), and T2‐prepared balanced steady state free precession (T2‐bSSFP) at 0.55T. AssessmentMRF T1and T2maps were reconstructed using (1) a low‐rank technique with sparse and locally low‐rank regularization (SLLR‐MRF) and (2) a deep image prior (DIP‐MRF). Accuracy and precision of MRF and conventional sequences were evaluated in a phantom. In vivo performance of MRF was evaluated in the 18 healthy subjects, with 7 subjects also undergoing conventional mapping. Myocardial T1and T2values were compared among methods and image quality scored by three readers (2, 3, and 4 years of experience) on a 5‐point scale. Statistical TestsLinear regression, Bland–Altman, intraclass correlation coefficient, and one‐way ANOVA withp < 0.05 considered significant. ResultsMean measurements in the left ventricular septum were 671 ± 31 ms (MOLLI), 761 ± 147 ms (SLLR‐MRF), and 686 ± 39 ms (DIP‐MRF) for T1, and 63.5 ± 5.7 ms (T2‐bSSFP), 47.5 ± 12.7 ms (SLLR‐MRF), and 45.2 ± 4.5 ms (DIP‐MRF) for T2. Compared to conventional mapping, DIP‐MRF exhibited significantly lower T2but no differences in T1(p > 0.99). Standard deviations within the myocardium were significantly lower with DIP‐MRF compared to SLLR‐MRF (39 vs. 147 ms for T1and 4.5 vs. 12.7 ms for T2). Overall image quality ratings were significantly lower for SLLR‐MRF (T1: 2.3, T2: 2.9), which were significantly lower compared to conventional mapping methods (T1: 3.4, T2: 3.9), and DIP‐MRF (T1: 3.8, T2: 4.1) received higher scores. Data ConclusionThis study demonstrated the feasibility of cardiac MRF on a commercial 0.55T system, enabled by a deep image prior reconstruction for denoising. Evidence Level2. Stage of Technical Efficacy1.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/lom3.10383
