J 2018

Impact of isotropic constitutive descriptions on the predicted peak wall stress in abdominal aortic aneurysms

MAN, V., S. POLZER, T.C. GASSER, Tomáš NOVOTNÝ, J. BURSA et. al.

Základní údaje

Originální název

Impact of isotropic constitutive descriptions on the predicted peak wall stress in abdominal aortic aneurysms

Autoři

MAN, V. (203 Česká republika, garant), S. POLZER (203 Česká republika), T.C. GASSER (752 Švédsko), Tomáš NOVOTNÝ (203 Česká republika, domácí) a J. BURSA (203 Česká republika)

Vydání

MEDICAL ENGINEERING & PHYSICS, OXFORD, ELSEVIER SCI LTD, 2018, 1350-4533

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

30212 Surgery

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Impakt faktor

Impact factor: 1.785

Kód RIV

RIV/00216224:14110/18:00102966

Organizační jednotka

Lékařská fakulta

UT WoS

000429510600005

Klíčová slova anglicky

Abdominal aortic aneurysm; Wall stress; Non-linear material model

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 10. 2. 2019 14:40, Soňa Böhmová

Anotace

V originále

Biomechanics-based assessment of Abdominal Aortic Aneurysm (AAA) rupture risk has gained considerable scientific and clinical momentum. However, computation of peak wall stress (PWS) using state-ofthe-art finite element models is time demanding. This study investigates which features of the constitutive description of AAA wall are decisive for achieving acceptable stress predictions in it. Influence of five different isotropic constitutive descriptions of AAA wall is tested; models reflect realistic non-linear, artificially stiff non-linear, or artificially stiff pseudo-linear constitutive descriptions of AAA wall. Influence of the AAA wall model is tested on idealized (n = 4) and patient-specific (n = 16) AAA geometries. Wall stress computations consider a (hypothetical) load-free configuration and include residual stresses homogenizing the stresses across the wall. Wall stress differences amongst the different descriptions were statistically analyzed. When the qualitatively similar non-linear response of the AAA wall with low initial stiffness and subsequent strain stiffening was taken into consideration, wall stress (and PWS) predictions did not change significantly. Keeping this non-linear feature when using an artificially stiff wall can save up to 30% of the computational time, without significant change in PWS. In contrast, a stiff pseudo-linear elastic model may underestimate the PWS and is not reliable for AAA wall stress computations. (C) 2018 IPEM. Published by Elsevier Ltd. All rights reserved.