Electricity: measuring and testing – Particle precession resonance – Using a nuclear resonance spectrometer system
Reexamination Certificate
2005-10-18
2005-10-18
Shrivastav, Brij (Department: 2859)
Electricity: measuring and testing
Particle precession resonance
Using a nuclear resonance spectrometer system
Reexamination Certificate
active
06956374
ABSTRACT:
A technique is set forth that is designed to reduce RF induced power in high field MR imaging that includes application of an initial contrast preserving phase of RF pulses. These initial RF pulses are designed to have a constant, relatively high flip angle over the initial contrast preserving phase. Following an effective TE, a ramp down phase is applied that has a limited number of RF pulses with a flip angle that is less than the flip angle of those in the initial contrast preserving phase. Further, the RF pulses in the ramp down phase have a flip angle that is decreased over the ramp down phase. This technique provides improved resolution and steady contrast and SNR, while significantly reducing induced RF power.
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Della Penna Michael A.
General Electric Company
Horton Carl B.
Shrivastav Brij
Vargas Dixomara
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