Method for determining the nuclear magnetisation distribution in a layer of a region under examination and NMR tomograph for carrying out the method

摘要

The invention relates to a method for determining the nuclear magnetisation distribution in a layer which yields very short echo times. Each sequence of this method comprises, in this case, at least two part-sequences of which one comprises a selective 180@ radio-frequency pulse and a non-selective radio-frequency pulse following thereon, and the other comprises a corresponding non-selective radio-frequency pulse. The resulting FID-signals are superimposed on each other in such a way that the components of the FID-signals resulting from the nuclear magnetisation outside the layer compensate one another. Since the non-selective radio-frequency pulses are relatively broad-band and can therefore have a short period, the result is short echo times and, consequently, a good signal-to-noise ratio. <IMAGE>