Fast adiabatic pulses
US6094049A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1997 |
| Grant date | Jul 25, 2000 |
| Priority date | — |
| Expiry date | Jun 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/446
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
New methods of generating optimal inversion pulses and adiabatic pulses in magnetic resonance imaging are disclosed. Trajectories, maximum sweep rates, and velocity profiles are used in defining an optimal pulse, over support regions. Adiabatic pulses are optimized by using the trajectory as a constraint of optimization, but selecting trajectories with velocity profiles, without using the adiabatic condition as a constraint for optimizing the velocity profile. A method or inverting MR spins substantially, independently of the pulse duration, by selecting a transition width between 1.4 and 1.9 and dividing that width by the pulse duration is disclosed; and A new method of inverting adiabatic, MR, amplitude modulated spins, with a trajectory defined by sin .alpha./cos .alpha., where .alpha.<0.9 and at least 50% of the trajectory is outside, in a z-x rotating frame of reference that rotates at the instantaneous frequency of the RF pulse is also taught.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.