Electricity: measuring and testing – Particle precession resonance – Using a nuclear resonance spectrometer system
Reexamination Certificate
2007-05-18
2010-06-15
Shrivastav, Brij B (Department: 2831)
Electricity: measuring and testing
Particle precession resonance
Using a nuclear resonance spectrometer system
Reexamination Certificate
active
07737690
ABSTRACT:
A system and method are provided for adjusting RF pulses and gradient waveforms to reduce B1field magnitude in MR imaging sequences. When an RF pulse is presented which has a high amplitude segment that would exceed a maximum B1magnitude, the system and method provided herein can apply a variable slew rate design technique. A slew rate of at least one gradient waveform can be varied to reduce a B1field magnitude during transmission of the high amplitude segment of the RF pulse. By controlling the slew rate of gradient waveforms for non-Cartesian k-space trajectories according to a calculated maximum allowable slew rate function, embodiments of the system and method can, in effect, reduce gradient amplitude.
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King Kevin F.
Xu Dan
General Electric Company
Shrivastav Brij B
Vargas Dixomara
Ziolkowski Patent Solutions Group, SC
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