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Abstract #2580

Correction of Motion-Induced Phase Variance in Single-Voxel 1H Spectroscopy

Brian Robert Keating1, Thomas Ernst2

1Department of Medicine, Unversity of Hawaii, Honolulu, HI, United States; 2Department of Medicine, University of Hawaii at Manoa, Honolulu, HI, United States

Subject motion introduces unwanted phase variance in the MR signal, resulting in image/spectral artifacts. We performed single-voxel brain scans (PRESS) while subject head movement was monitored by an external optical tracking system. The motion-induced phase evolution was estimated based on tracking data and knowledge of the gradient waveforms. Phase corrections were applied in post-processing, resulting in improved phase coherence and increased SNR on real spectra. These results demonstrate the promise of a high-accuracy motion tracking system for reducing movement-related artifacts in phase-sensitive modalities.

Keywords

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