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Minimizing TE in moment-nulled or flow-encoded two- and three-dimensional gradient-echo imaging.

M A Bernstein·A Shimakawa·N J Pelc
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Abstract

A method for minimizing field-echo delay in moment-nulled gradient-echo imaging is presented. Even though ramps are accounted for, the analysis yields simple closed-form solutions. The method is then generalized to the section-select waveform for three-dimensional volume imaging and to flow encoding for phase-contrast imaging. Three strategies for first-moment selection in phase-contrast imaging are discussed, including a new strategy that always yields the minimum echo delay. Trapezoidal and triangular gradient lobe shapes are analyzed.

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M A Bernstein, A Shimakawa, N J Pelc. Minimizing TE in moment-nulled or flow-encoded two- and three-dimensional gradient-echo imaging.. https://doi.org/10.1002/jmri.1880020517

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