| 摘要 |
Method for MR imaging of an object in which various RF and magnetic field gradient pulse sequences are used to produce transverse magnetization and to generate echoes. The RF pulse sequence may include a sinusoidal waveform component defined by either y=sin x, 0<=x <=4(pi); y=cos x, 0<=x <=4(pi); or y=sin x, 0<=x<=(pi)/2, y=cos x, (pi)/2<=x<=(pi); and a phase component defined by either y=0, 0<=x<=2(pi), y=(pi), 2(pi)<=x<=4(pi); or y =-2(pi)cos x, 0<=x<=(pi)/2, y=-2(pi)sin x, (pi)/2<=x<=(pi). The selected waveform and phase components may be combined to form a first, composite RF signal and the Hilbert transform of the composite RF signal selected as a second RF signal. Alternately, the second RF pulse sequence may be comprised of first and second phase shifting linear ramps. The selected gradient magnetic field pulse sequences may include a first sinusoidal readout pulse sequence defined by y=ax sin x, 0<=x<=n(pi) and a second sinusoidal readout pulse sequence defined by y=ax cos x, 0<=x<=n(pi), first and second constant magnitude phase encoding pulse sequences, or a square wave as a readout pulse sequence and a series of positive amplitude spikes positioned at each transition for the readout pulse sequence as a phase encode pulse sequence.
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