Tissue hardness measurement using the radiation force of focused ultrasound

A technique for measuring hardness in which the impulsive radiation force is focused ultrasound is used to generate localized deformation of the tissue and the applied force and/or the deformation are measured as a function of time by a conventional pulse-echo technique is proposed. An attempt is made to derive some characteristic values from the curve as figures of tissue hardness. The decay of applied force measured while keeping the deformation constant proved to give a good figure. This preliminary experiment indicates that the proposed technique is feasible.<<ETX>>