Stéphane Avril — Page 2

arXiv2011

Identification of Heterogeneous Elastic Properties in Stenosed Arteries: a Numerical Plane Strain Study

Assessing the vulnerability of atherosclerotic plaques requires an accurate knowledge of the mechanical properties of the plaque constituents. It is possible to measure displacements in vivo inside a plaque using magnetic resonance imaging. An important issue is to solve the inverse problem that consists in estimating the elastic properties inside the plaque from measured displacements. This study focuses on the identifiability of elastic parameters e.g. on the compromise between identification time and identification accuracy. An idealised plane strain. Finite Element (FE) model is used. The effects of the FE mesh, of the a priori assumptions about the constituents, of the measurement resolution and of the data noise are numerically investigated.

physics.med-ph↗

arXiv2009

Etude mécanique des articles de contention et de leurs effets sur la jambe humaine. Mechanical investigation of compression stockings and of their effects on the human leg

This paper presents a synthesis of different studies willing to bring a scientific insight into leg compression, which is the process of applying external compression forces onto the human leg with stockings or socks, for enhancing the venous flow. It seems obvious that the pressure distribution on the leg affects the blood flow in the veins. However, the pressure distribution that leads to the optimal blood flow is not trivial, and it is different with regard to the application: medical treatment or recovering after an effort in sports. In order to improve the scientific knowledge about this topic, a numerical 2D model was set up for computing stress fields inside the leg, accounting for the actual material properties of both the compression stocking and of the leg biological tissues. Suitable identification methods, based either on model updating from digital image correlation (for the compression stockings), or on image warping and model updating from MRI scans (for the internal leg tissues), were developed for retrieving these material properties.

physics.med-ph↗