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Abstract #2307

Efficient Gradient Waveform Design with 0th and 1st Moment Control for Flow Compensated BSSFP

Daniel Posfai1, J. Andrew Derbyshire2, Daniel A. Herzka1

1Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, MD, United States; 2Tornado Medical Systems, Toronto, Ontario, Canada

Time-efficient gradient waveforms with pre-defined 1st moments (M1) can be difficult to design. These gradients are at the core of many techniques such as phase contrast or flow-compensated acquisitions. A new method of designing hardware-optimized gradient waveforms is presented. The design strategy works in both logical and physical coordinate systems, pushing gradient hardware to limitations. The method works directly on a rasterized time scale, and yields complete control of the 0th (M0), or M0 and M1 of waveforms. Design of an efficient balanced steady-state free precession (bSSFP) sequence is demonstrated, along with partially and fully M1-nulled (M1=0 mT/m*us2) variants useful for flow-compensated bSSFP.

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Keywords

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