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Abstract #2600

Gradient Waveform Measurement Using Prephased Gradient Moments.

Peter Latta1, Marco L. H. Gruwel1, Vladimr Jell2, Boguslaw Tomanek1

1Institute for Biodiagnostics, National Research Council of Canada, Winnipeg, Manitoba, Canada; 2MR Application Development, Siemens AG, Healthcare, Erlangen, Germany

One of the commonly used methods for k-space trajectory/gradient waveform characterization is based on utilizing the FID phase evolution sampled from a thin slice excited at a known distance. In many cases like breast or extremity imaging, there is no source of signal near the magnets isocenter. This introduces problems with rapid phase accrual. Additional complications arise from measuring high gradient amplitudes when modification of this approach is necessary to avoid problems with low signal amplitudes caused by spin dephasing. Here we propose alternative methods for gradient characterization based on the gradient moment mapping.

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Keywords

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