摘要 |
<p>IN NMR images, which are constructed from resonance signals, for examples using Fourier zeugmatography, coherent interference effects resulting, for example, from "Leak-through" of NMR signals from one sequence to a next sequence of resonance signals, can cause artefacts to occur in the images, which, depending upon the kind of interference, become manifest in the image as interference lines, ghost images or conspicuouc dots. A method is proposed for reducing the effect of this interference by smearing the artefacts out over the image as noise. For this purpose, the phase of the reference signals is randomly modulated between successive measurement cycles of the resonance signals. The reference signal is used to form excitation pulses for producing resonance signals in a body and further for the synchronous detection of the resonance signals.</p> |