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Free-breathing volumetric fat/water separation by combining radial sampling, compressed sensing, and parallel imaging.

ABSTRACT: Conventional fat/water separation techniques require that patients hold breath during abdominal acquisitions, which often fails and limits the achievable spatial resolution and anatomic coverage. This work presents a novel approach for free-breathing volumetric fat/water separation.Multiecho data are acquired using a motion-robust radial stack-of-stars three-dimensional GRE sequence with bipolar readout. To obtain fat/water maps, a model-based reconstruction is used that accounts for the off-resonant blurring of fat and integrates both compressed sensing and parallel imaging. The approach additionally enables generation of respiration-resolved fat/water maps by detecting motion from k-space data and reconstructing different respiration states. Furthermore, an extension is described for dynamic contrast-enhanced fat-water-separated measurements.Uniform and robust fat/water separation is demonstrated in several clinical applications, including free-breathing noncontrast abdominal examination of adults and a pediatric subject with both motion-averaged and motion-resolved reconstructions, as well as in a noncontrast breast exam. Furthermore, dynamic contrast-enhanced fat/water imaging with high temporal resolution is demonstrated in the abdomen and breast.The described framework provides a viable approach for motion-robust fat/water separation and promises particular value for clinical applications that are currently limited by the breath-holding capacity or cooperation of patients. Magn Reson Med 78:565-576, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

SUBMITTER: Benkert T

PROVIDER: S-EPMC5344788 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Free-breathing volumetric fat/water separation by combining radial sampling, compressed sensing, and parallel imaging.

Benkert Thomas T Feng Li L Sodickson Daniel K DK Chandarana Hersh H Block Kai Tobias KT

Magnetic resonance in medicine 20160909 2

<h4>Purpose</h4>Conventional fat/water separation techniques require that patients hold breath during abdominal acquisitions, which often fails and limits the achievable spatial resolution and anatomic coverage. This work presents a novel approach for free-breathing volumetric fat/water separation.<h4>Methods</h4>Multiecho data are acquired using a motion-robust radial stack-of-stars three-dimensional GRE sequence with bipolar readout. To obtain fat/water maps, a model-based reconstruction is us ...[more]

PMID: 27612300

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Free-breathing volumetric fat/water separation by combining radial sampling, compressed sensing, and parallel imaging.

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Free-breathing volumetric fat/water separation by combining radial sampling, compressed sensing, and parallel imaging.

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