Séminaire Creatis : Shear wave elastography for muscle biomechanics, Jean-Luc Gennisson , INSERM

In vivo muscle biomechanical properties are classically deduced from inverse dynamics or measures of joint torque performed using ergometers. However, this provides information about the combined behavior of several structures. Thus, it is complicated to isolate the behavior of an individual muscle. Ultrasound elastography techniques have been developed with the aim to non-invasively assess localized stiffness. In this presentation we focused on the supersonic shear imaging technique that allows us to recover stiffness by looking at the propagation of shear waves. In the case of isotropic, homogeneous and quasi-incompressible biological tissues, the propagation velocity is directly linked to the shear elastic modulus. However, this link is not so obvious in muscles due to their anisotropy. Here we present how stiffness as well as viscosity can be estimated in fusiform muscles but also in pennate muscles by using specific ultrasound sequences that allows to directly recover anisotropy in a 2D imaging plane. Fi