Water/fat separated Echo Planar Time-resolved Imaging (EPTI) for efficient distortion-free multi-contrast imaging

Motivation: Echo Planar Time-resolved Imaging (EPTI) can produce distortion- and blurring-free multi-echo images with high efficiency. For its broader application such as in body imaging, the challenge of fat suppression/separation needs to be addressed. Goal(s): Achieving efficient water/fat separation using EPTI for high-quality fast multi-contrast/quantitative imaging in the presence of fat tissues. Approach: In this study, water/fat separated EPTI (WFS-EPTI) was proposed to achieve this by: (1) designing a novel in-phase and out-of-phase EPTI acquisition and encoding scheme; and (2) adopting a k-space-based water/fat separation method. Results: Experimental results demonstrated the efficacy of WFS-EPTI for water/fat separation and fat-robust distortion-free multi-contrast/quantitative imaging. Impact: The proposed WFS-EPTI effectively separates water and fat signals, while providing efficient acquisition of high-resolution, distortion-free multi-contrast images and quantitative maps. It can extend EPTI to a broader range of applications.