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bioRxiv · 10.1101/2024.05.13.593911

Single-shot water-fat imaging with multi-echo blip-rewound EPI

Wu, W.
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Abstract

PurposeTo develop a method for single-shot water-fat imaging. MethodsSingle-shot blip-rewound EPI (rEPI) is a fast imaging technique that can acquire multiple echo MRI images with a snapshot. Dixons method separates water and fat signals using signals acquired with different echo times. Combining multi-echo rEPI with properly chosen echo times and Dixon-based post-processing generates water and fat images with a single-shot scan. ResultsPhantom and in vivo experiments were performed to evaluate the proposed method. In phantom scans, water and fat signals are robustly separated using the proposed method, and the obtained water signal is much cleaner than that obtained by conventional EPI acquisition with fat suppression. In vivo experiments show that fat suppression can be obtained using the proposed method without fat saturation pulses, reducing SAR and shortening scan time. In addition, fat signal can also be reconstructed based on the proposed method. ConclusionA single-shot water-fat imaging technique has been successfully developed, a significant advancement that offers speed and robustness in separating water and fat signals for human MRI scans.

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Wu, W.. 2024-05-15. Single-shot water-fat imaging with multi-echo blip-rewound EPI. https://doi.org/10.1101/2024.05.13.593911

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