  Making use of the poroelastic theory for hydrated polymeric matrices, the
ultrasound (US) propagation in a gel medium filled by spherical cells is
studied . The model describes the connection between the poroelastic structure
of living means and the propagation behavior of the acoustic waves. The
equation of fast compressional wave, its phase velocity and its attenuation as
a function of the elasticity, porosity and concentration of the cells into the
gel external matrix are investigated. The outcomes of the theory agree with the
measurements done on PVA gel scaffolds inseminated by porcine liver cells at
various concentrations. The model is promising in the quantitative non-invasive
estimation of parameters that could asses the change in the tissue structure,
composition and architecture.
