P7-Modeling of function-perfusion-deformation interaction on liver lobules and cellular scale based on a bi-scale continuum FEM model

The project is part of the research group 5151 "Quantification of the liver perfusion-function relationship in complex resection - a systems medicine approach" (QuaLiPerF). Within this research unit, this project aims to numerically simulate the mechanically and biologically coupled perfusion-function processes on the lobular level. The hepatic lobular level is the connection between the next larger (organ vascular system) and the next smaller (cell system) level. This allows the simulation of two- and three-dimensional (2D/3D) liver lobule groups (up to 20). We will study the changes in blood perfusion during fat accumulation and calculate the transient spatial distribution of fat accumulation in the liver lobules. The model will provide information on perfusion changes induced by fat accumulation via portal vein ligation (PVL) and liver resection ((e)PHx). We will extend the model to simulate tissue growth and structural changes during liver regeneration. A time-dependent reorientation approach of the sinusoids will be incorporated. The deformation, flow and transport processes will be modelled using a system of coupled partial differential equations (PDE), while the metabolic processes and fat accumulation will be described using a systems biology approach using a system of ordinary differential equations (PDE-ODE coupling). The high-resolution, hyperelastic and porous lobular model is developed and verified within a thermodynamically consistent continuum mechanical data- and knowledge-driven, multiphase and multi-scale approach. The model is directly founded on first principles of mechanics and based on the extended theory of porous media (eTPM). In addition, the lobular model is parameterized and verified by including experimental, clinical and in silico data obtained by partners from the research group.