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Abstract PurposeThe reproducibility of scientific reports is crucial to advancing human knowledge. This paper is a summary of our experience in replicating a balanced SSFP half‐radial dual‐echo imaging technique (bSTAR) using open‐source frameworks as a response to the 2023 ISMRM “repeat it with me” Challenge. MethodsWe replicated the bSTAR technique for thoracic imaging at 0.55T. The bSTAR pulse sequence is implemented in Pulseq, a vendor neutral open‐source rapid sequence prototyping environment. Image reconstruction is performed with the open‐source Berkeley Advanced Reconstruction Toolbox (BART). The replication of bSTAR, termed open‐source bSTAR, is tested by replicating several figures from the published literature. Original bSTAR, using the pulse sequence and image reconstruction developed by the original authors, and open‐source bSTAR, with pulse sequence and image reconstruction developed in this work, were performed in healthy volunteers. ResultsBoth echo images obtained from open‐source bSTAR contain no visible artifacts and show identical spatial resolution and image quality to those in the published literature. A direct head‐to‐head comparison between open‐source bSTAR and original bSTAR on a healthy volunteer indicates that open‐source bSTAR provides adequate SNR, spatial resolution, level of artifacts, and conspicuity of pulmonary vessels comparable to original bSTAR. ConclusionWe have successfully replicated bSTAR lung imaging at 0.55T using two open‐source frameworks. Full replication of a research method solely relying on information on a research paper is unfortunately rare in research, but our success gives greater confidence that a research methodology can be indeed replicated as described.
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This content will become publicly available on January 1, 2026
T1 and T2 measurements across multiple 0.55T MRI systems using open‐source vendor‐neutral sequences
Abstract PurposeTo compare T1 and T2 measurements across commercial and prototype 0.55T MRI systems in both phantom and healthy participants using the same vendor‐neutral pulse sequences, reconstruction, and analysis methods. MethodsStandard spin echo measurements and abbreviated protocol measurements of T1, B1, and T2 were made on two prototype 0.55 T systems and two commercial 0.55T systems using an ISMRM/NIST system phantom. Additionally, five healthy participants were imaged at each system using the abbreviated protocol for T1, B1, and T2 measurement. The phantom measurements were compared to NMR‐based reference measurements to determine accuracy, and both phantom and in vivo measurements were compared to assess reproducibility and differences between the prototype and commercial systems. ResultsVendor‐neutral sequences were implemented across all four systems, and the code for pulse sequences and reconstruction is freely available. For participants, there was no difference in the mean T1 and T2 relaxation times between the prototype and commercial systems. In the phantom, there were no significant differences between the prototype and commercial systems for T1 and T2 measurements using the abbreviated protocol. ConclusionQuantitative T1 and T2 measurements at 0.55T in phantom and healthy participants are not statistically different across the prototype and commercial systems.
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- Award ID(s):
- 1828736
- PAR ID:
- 10572559
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Magnetic Resonance in Medicine
- Volume:
- 93
- Issue:
- 1
- ISSN:
- 0740-3194
- Page Range / eLocation ID:
- 289 to 300
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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