Determination of patient-specific material properties of cardiovascular tissue through noninvasive measurements

The mechanical properties of human biological tissue vary greatly. Hence, patient-specific material properties are a must for realistic intra-operative simulations. The determination of arterial material properties should be based on experimental data (i.e. diameter, length, intramural pressure, axial force and stress-free geometry). Currently, clinical data provide only non-invasively measured pressure-diameter data for superficial arteries (e.g. common carotid and femoral artery). To overcome this lack of information, an approach has been proposed taking into account certain assumptions regarding the in situ configuration and stress states of arterial walls [2]. This paper presents a method towards validation of this and other approaches. A finite element model of a simplified artery was used as a mock experimental situation. This method enables exact knowledge of the actual material properties, thereby allowing a qualitative evaluation of the different approaches. The results of the validation show that the material parameters estimated with the noninvasive approaches can deviate quite a lot from the real material properties. Future work is directed towards improving the existing noninvasive parameter estimation approaches.status: publishe