Conference Paper

Self-Navigated Ideal Water-Fat Separation with Variable K-Space Averaging.

DOI: 10.1109/ISBI.2009.5192998 Conference: Proceedings of the 2009 IEEE International Symposium on Biomedical Imaging: From Nano to Macro, Boston, MA, USA, June 28 - July 1, 2009
Source: DBLP

ABSTRACT Water-fat separation has been an important technique in MRI. IDEAL (Iterative Decomposition of water and fat with Echo Asymmetry and Least squares estimation) water-fat separation is a robust method to achieve water-fat separation, and has been adopted in quantitative analysis of adiposity. The presence of motion during acquisition causes artifacts, which can result in quantification inaccuracies. To overcome this challenge, a double-echo navigator technique was incorporated in the IDEAL sequence to monitor the signal fluctuation caused by motion. Retrospective motion correction led to a substantial reduction of motion artifacts, thereby improving the accuracy and robustness of the quantification. In addition, a variable k-space averaging for motion correction is proposed. By concentrating the averaging at the center of k-space, it achieved same motion correction performance with less acquired k-space profiles. Water/oil phantom data and animal hepatic adiposity data were acquired, and results were compared with and without motion correction. Simulated results were generated to evaluate the variable k-space averaging.

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