Method for determining the spectral distribution of nuclear magnetisation

摘要

The invention relates to a method for determining the spectral distribution of nuclear magnetisation, in which a plurality of sequences in the presence of a stationary homogeneous magnetic field act on an examination region, the stimulated echo signal generated in each case in the section region of three layers, each excited by one layer-selective high-frequency pulse in conjunction with a magnetic field gradient (irrotational field), being analysed, as well as to an arrangement for implementing this method. In order to make it possible to measure the spectra of a plurality of mutually separated volume regions, without lengthening the measuring time and without degrading the stimulated echo signals from these volume regions by signals which are produced outside the volume regions, the invention provides for each sequence to contain a plurality of partial sequences, for each partial sequence to include the generation and reception of a stimulated echo signal in a section region assigned to the partial sequence in question and for the mean frequency and the bandwidth of the three high-frequency pulses of each partial sequence and the direction and the strength of the magnetic field gradients accompanying the high-frequency pulses are chosen so that the nuclear magnetisation in none of the section regions is influenced by more than one partial sequence. <IMAGE>