We have developed a new system for measuring the viscoelastic property of the skin that involves no direct contact with the body surface. Traditional methods for measuring the elastic property of the skin required direct contact with the skin surface and involved many inconveniences in regard to clinical application such as pain and infection during measurement. In this study, we investigate the fundamental validity of this system. This method employs compressed air pressure to apply pressure to an area (6 mm in diameter) on the body surface. The deformation of the central part of this area is then precisely measured with a laser displacement meter. Tissue elasticity and viscosity is calculated from variation in time of displacement and load. The elastic modulus was calculated based on the Boussinesq equation. Because the dermal measuring result proved to be comparatively similar to the Maxwell model, the coefficient of viscosity modulus prescribed in the model can be calculated with this method. Using the system developed in our research, the elastic modulus and coefficient of viscosity were measured for the male and female skin surfaces of the forearm and heal of the foot. In both cases, the elastic modulus of the male forearm was larger than that of the female, while the coefficient of viscosity obtained for the male weas smaller than that of the female. Thus, we confirmed precision and repeatability by measuring the viscoelastic properties of the skin, and in particular, usability in terms of its ability to quantitatively calculate elastic modulus and viscosity.
