High frequency elastography for in-vivo study of the mechanical behavior of skin

The aim of this paper is to show the potential of high frequency elastography in the evaluation of the in-vivo mechanical behavior of human skin. In the first part we describe the filtered and staggered strain estimation (FSSE) which is a new elastographic algorithm based on the staggered strain estimation (SSE) method. This algorithm does not integrate the global stretching, commonly used in the case of global compression stress, but it uses a low-pass filtering to estimate the axial strain in a complex medium such as the skin. We present also a lateral displacement detection technique based on a parabolic interpolation. In the second part we expose a PVA-cryogel phantom and in-vivo experiments conducted with two combined devices: our 20 MHz real time sonographer (DERMCUP2020®) used for ultrasound imaging and a patented device devoted to apply uniaxial stretching stress. The in-vivo mechanical behavior of human skin is illustrated using the multi-stretching FSSE technique and elastograms and lateral displacement images are shown in the results.