Multiphysical modelling of mechanical behaviour of soft tissue : application to prostate

Abstract

The aim of this thesis is to propose computational methodologies to analyse how the morphological and microstructural changes in the soft tissues, caused by various pathological conditions, influence the mechanical properties of tissue. More importantly, how such understanding could provide more insights into the mechanical properties of tissue for the purpose of quantitative diagnosis. To achieve this objective, statistical analysis of tissue microstructure based on image processing of tissue histology has been carried out. The influence of such microstructural changes due to different pathological conditions has also been compared to the mechanical properties of the tissue by means of the homogenization approach. To understand better the influence of fluid movement in viscoelastic behaviour of tissue, an optimization based method using numerical homogenization that is integrated with fluid-structure interaction (FSI) modelling is presented. The microstructures of soft tissue are treated as bi-phasic materials, solid material representing the cells and extracellular materials and fluid phase for the interstitial fluid. Such proposed method would be beneficial for quantitative assessment of mechanical properties of soft tissue, as well as understanding the role of multiscale microstructural features of soft tissues in its functionality. It is envisaged that this work will pave the road towards more precise characterization of mechanical properties of soft tissue which can be implemented to non-invasive diagnostic techniques, in order to improve the effectiveness of a range of diagnostic methods such as palpation for primary prostate diagnosis and, more importantly, the life quality of patients.