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Abstract #3346

Autocalibrated Parallel MR Spectroscopic Imaging Without Extra Autocalibrating K-Space Lines

Michael Abram Ohliger1, Simon Hu1, Peder E. Z. Larson1, Robert Bok1, Peter Shin1, James Tropp2, Lucas Carvajal1, Sarah J. Nelson1, John Kurhanewicz1, Daniel

1Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, United States; 2General Electric Healthcare, Fremont, CA, United States

Autocallibrated parallel MR strategies generally rely on a densely sampled center of k-space to obtain coil array reference information. This dense sampling can be a large burden when applied to spectroscopic imaging. We present a new strategy for MR spectroscopic imaging with parallel reconstruction that eliminates the need for extra auto-calibrating lines. Combining spatial and spectral undersampling, select chemical species alias to unused portions of the spectrum, and can be used as sensitivity references. For an undersampling factor of 3, 38% fewer phase encode lines are acquired. Theoretical background, numerical simulations, and in vivo examples are presented using hyperpolarized 13C.

Keywords

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