Prestressing patient-specific biomechanical problems under finite deformation

In simulation of biomechanical structures the patient specific geometry of the object of interest is very often reconstructed from in–vivo medical imaging such as CT scans. Such geometries therefore represent a deformed configuration stressed by typical in–vivo conditions. Commonly, such structures are considered stress–free in simulation. In this contribution we present and compare two methods to introduce a physically meaningful stress/strain state to the obtained geometry for simulations in the finite strain regime and demonstrate the necessity of such prestressing techniques. One method is based on an inverse design analysis (ID) to calculate a stress–free reference configuration. The other method developed by the authors is based on a modified updated Lagrangian formulation (MULF). Formulation of both methods is provided and implementation issues are discussed. Applicability and accurateness of both approaches are compared and evaluated utilizing fully three dimensional patient specific abdominal aortic aneurysm structures within the context of wall stress and fluid–structure interaction analysis.     «

In simulation of biomechanical structures the patient specific geometry of the object of interest is very often reconstructed from in–vivo medical imaging such as CT scans. Such geometries therefore represent a deformed configuration stressed by typical in–vivo conditions. Commonly, such structures are considered stress–free in simulation. In this contribution we present and compare two methods to introduce a physically meaningful stress/strain state to the obtained geometry for simulations...     »