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Abstract #4299

Direct Estimation of Hyperpolarized Metabolites with IDEAL Spiral CSI

Jeremy Gordon1, Sean B. Fain1, 2, Kevin Johnson1

1Medical Physics, University of Wisconsin-Madison, Madison, WI, United States; 2Radiology, University of Wisconsin-Madison, Madison, WI, United States

Hyperpolarization dramatically improves signal from 13C labeled molecules; however, the transient polarization must be used efficiently. Highly efficient acquisition trajectories, such as spirals, are well-suited to maximize utilization of hyperpolarization but are limited by off-resonance blurring, forcing short readout duration spirals for imaging. Here, we propose to use 1H data to provide a field-map estimate, reducing reconstruction of chemically-shifted species to a linear problem. A least-squares technique is presented to directly solve for 13C metabolites, generating images corrected for Bo inhomogeneity and with minimal off-resonance blurring. This technique permits non-Cartesian acquisitions with longer readouts, greatly increasing 13C spiral CSI efficiency.

Keywords

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