| 摘要 |
After exciting magnetic resonance (60), a train of magnetic resonance echoes including echoes (701, 702, . . . ) is induced, e.g., with a series of refocusing pulses including pulses (721, 722, . . . ). The echoes are phase and frequency-encoded appropriately for generating at least first and second images (94, 98). The first image echoes are interleaved with the second image echoes, for example, odd-numbered echoes for the first image and even-numbered echoes for the second image. To select the effective first/second image echo time, the first/second image echo which follows resonance excitation by a time closest to the selected first/second image effective echo time is given the zero or minimum phase-encoding. Nearby echoes being encoded with low phase-encode angles. In this manner, the effective echo times of the first and second images are selected to have preselected relative contrasts of diagnostic interest. Typically, the effective echo times of both the first and second image is less than the time between resonance excitation and the eighth echo, even although the echo train may be 32, 64, 128, or more echoes.
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