Skin anisotropy in vivo and initial natural stress effect: a quantitative study using high-frequency static elastography.

Background: Most studies on skin anisotropy are carried out in an "average" context, e.g. with an extension/compression test on the skin in vivo, the elastic modulus being estimated for the stretched zone overall.

Mechanical skin thinning-to-thickening transition observed in vivo through 2D high frequency elastography.

This study was based on two dimensional (2D) high frequency elastography to describe quantitatively the mechanical behavior of the human dermis in vivo. The study was conducted on the forearm skin and elastographic tests were performed using a combination of two devices: an extensiometer developed for the in vivo study of the mechanical behavior of the skin using uniaxial stretching stress, and a 20MHz real time sonographer (Dermcup 2020™) for ultrasound skin imaging. The staggered strain estimation algorithm (SSE) was used to produce elastograms.