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Abstract #3777

Measurement of Short Time Constant Eddy Currents with Zero TE Imaging

Kevin F. King1, Graeme C. McKinnon1, Xu Dan1, Joseph K. Maier1

1GE Healthcare, Waukesha, WI, United States

Eddy currents are typically measured using small samples with a special fixture. As part of an image-based tool without a special fixture, we propose to measure eddy currents with time constants of a few hundred microseconds or less with ultrashort TE imaging. A spherical phantom was scanned with eddy current generating preparation gradients followed by readouts at increasing delays. The image phase was fit to spatially linear terms which were then fit to sums of decaying exponentials. Reasonable agreement with fixture-based decay curves and comparable correction for ghosting in single-shot EPI and spectral-spatial RF pulse banding was found.

Keywords

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