Depth Evaluation of Soft Tissue Mimicking Phantoms Using Surface Acoustic Waves

Abstract

Surface acoustic wave (SAW) shows advantages in revealing skin mechanical properties. In this paper, we evaluates the elasticity of tissue mimicking phantoms by inversion of SAWs phase velocity to Young's Modulus, the estimated SAWs evaluating depth is determined based on the assumption of that SAWs penetration approximately equals one wavelength. The tissue mimicking phantoms are made of agar with concentration of 1%, 2% and 3%. Their elasticity tested from our system is 13.3kPa, 53.4kPa and 257.9kPa respectively, with expected gradient. The evaluation depth is then estimated as 0.542mm to 3.403mm underneath the phantom surface, which indicates that this method is suitable to measure elasticity in dermis layer of skin.