Applicability of simplified computational models in prediction of peak wall stress in abdominal aortic aneurysms

Article type: Research Article

Authors: Novak, Kamil | Polzer, Stanislav | Bursa, Jiri^*

Affiliations: Institute of Solid Mechanics, Mechatronics and Biomechanics, Brno University of Technology, Brno, Czech Republic

Correspondence: [*] Corresponding author: Jiri Bursa, Institute of Solid Mechanics, Mechatronics and Biomechanics, Brno University of Technology, Technicka 2896/2, Brno 61669, Czech Republic. Tel.: +420 54114 2868; E-mail: bursa@fme.vutbr.cz.

Abstract: In the paper impact of different material models on the calculated peak wall stress (PWS) and peak wall rupture risk (PWRR) in abdominal aortic aneurysms (AAAs) is assessed. Computational finite element models of 70 patient-specific AAAs were created using two different material models – a realistic one based on mean population results of uniaxial tests of AAA wall considered as reference, and a 100 times stiffer artificial model. The calculated results of PWS and PWRR were tested to evaluate statistical significance of differences caused by the non-realistic material model. It was shown that for majority of AAAs the differences are insignificant but for some 10% of them their relative differences exceed 20% which may lead to incorrect decisions on their surgical treatment. This percentage of failures favours application of realistic material models in clinical practise although they are much more time-consuming.

Keywords: Abdominal aortic aneurysm, peak wall stress, finite element model

DOI: 10.3233/THC-171024

Journal: Technology and Health Care, vol. 26, no. 1, pp. 165-173, 2018