Elastic properties imaging by periodical displacement NMR measurements (EPMRI)

The method described here for the detection of the periodical sample element displacement, consisting in the determination of the nuclear spin phase shift between magnetic field gradient pulses can be applied in two ways: (I) using the synchronization of gradient pulses G with the elastic wave phase; and (II) without synchronization. The combination of the measurement of ΔΦ with magnetic resonance imaging methods (MRI) can provide new diverse possibilities of applying MRI in medical diagnostics as well as in basic examinations. Accounting for this, the following items can be mentioned: mapping of adiabatic compressibility coefficient, mapping of amplitude wave damping coefficient α and mapping of the elastic relaxation processes. It can be evaluated that the precision of the method proposed for determining the displacement evoked by the elastic wave will not be worse than that of the measurement of the diffusion coefficient. It can be concluded that the method presented makes it possible to detect and map the interesting, in view of medical and material diagnostics, viscoelastic properties of matter. The development of the method described provided the basis for a method called nuclear elastomagnetic resonance