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Improved cardiac sodium MR imaging by density-weighted phase-encoding.

Andreas Greiser·Axel Haase·Markus von Kienlin
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Abstract

PURPOSE: To show that density-weighted (DW) k-space sampling improves the quality of human cardiac sodium imaging, a novel method was implemented that combines the high signal-to-noise efficiency of three-dimensional phase-encoding with the advantageous localization performance of nonuniform sampling. A simulation demonstrates substantially reduced blood contamination in the myocardium. MATERIALS AND METHODS: At 2.0 T, DW cardiac "fast" sodium images with a voxel size of 844 microL in seven minutes and "high-resolution" scans in 30 minutes with a voxel size of 570 microL were acquired. For comparison, conventional gradient-echo imaging was also performed. RESULTS: In the DW images, a myocardial signal-to-noise ratio (SNR) of 16.0 in the left ventricle and 8.5 in the septum (N = 4) was measured. With longer experimental duration (about 30 minutes; N = 3), the image quality and the SNR could be further improved (voxel size: 570 microL; SNR: blood 16.1, septum 10.6). Compared to the gradient-echo images, the image quality was substantially improved. CONCLUSION: This new method for human cardiac sodium imaging provides high image quality combined with optimal sensitivity and thus may improve the clinical applicability of 23Na cardiac MRI.

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Computer SimulationHumansImage EnhancementImage Processing, Computer-AssistedImaging, Three-DimensionalMagnetic Resonance ImagingMyocardiumSodiumSodium IsotopesJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

Andreas Greiser, Axel Haase, Markus von Kienlin. 2005. Improved cardiac sodium MR imaging by density-weighted phase-encoding.. https://doi.org/10.1002/jmri.20237

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