Deformačně-napěťová analýza aneurysmatu břišní aorty

STRESS STRAIN ANALYSIS OF ABDOMINAL AORTIC ANEURYSM

conference paper

en

Aneurysms of arteries are rather frequent diseases of cardiovascular system, especially among older people, endangering them by their rupture. They are found especially in some of the brain arteries and in abdominal part of aorta. Aneurysm of abdominal aorta (AAA) is a pathological change in lumen (inner diameter) of aorta, with synchronous decrease of wall thickness, often in the whole part between renal arteries and aortic bifurcation. This changes are mostly accompanied by creation of wall thrombus in the deformed region with decreased flow near the aortic wall. The study presented in [1] proved that maximum principal stresses in AAA wall (calculated using a 3D model) predict the risk of its rupture better than the mere maximum diameter of the aneurysm, used as a criterion for decision about its operability in clinical practice. The stress-strain analysis of AAA presented in this paper focuses on comparison of 2D and 3D finite element models of AAAs. Comparison of 2D and 3D models will enable us to evaluate the credibility of the 2D computational model that is highly convenient for computer aided decisions in clinical practices. The significance of axial prestretch in aortic wall can be estimated as well.

Příspěvek prezentuje 3D MKP model aneuryzmatu břišní aorty, jehož geometrie je vytvpořena na základě CT snímků pacienty. Rozložení napětí v modelu ukazuje, že maximální napětí se nevyskytují v místě maximálního průměru, a že pro jejich posouzení nestačí 2D model v místě největšího průměru.

Aneurysms of arteries are rather frequent diseases of cardiovascular system, especially among older people, endangering them by their rupture. They are found especially in some of the brain arteries and in abdominal part of aorta. Aneurysm of abdominal aorta (AAA) is a pathological change in lumen (inner diameter) of aorta, with synchronous decrease of wall thickness, often in the whole part between renal arteries and aortic bifurcation. This changes are mostly accompanied by creation of wall thrombus in the deformed region with decreased flow near the aortic wall. The study presented in [1] proved that maximum principal stresses in AAA wall (calculated using a 3D model) predict the risk of its rupture better than the mere maximum diameter of the aneurysm, used as a criterion for decision about its operability in clinical practice. The stress-strain analysis of AAA presented in this paper focuses on comparison of 2D and 3D finite element models of AAAs. Comparison of 2D and 3D models will enable us to evaluate the credibility of the 2D computational model that is highly convenient for computer aided decisions in clinical practices. The significance of axial prestretch in aortic wall can be estimated as well.

Keywords: Stress-strain analysis, abdominal aortic aneurysm, finite element model

2006

13.11.2006

Brno University of Technology, Institute of Solid Mechanics, Mechatronics and Biomechanics

Hrotovice

80-214-3232-2

Human Biomechanics 2006

178–179

2