title: A simulation framework for estimating wall stress distribution of abdominal aortic aneurysm.
abstract: Abdominal aortic aneurysm (AAA) rupture is believed to occur when the mechanical stress acting on the wall exceeds the strength of the wall tissue. In endovascular aneurysm repair, a stent-graft in a catheter is released at the aneurysm site to form a new blood vessel and protect the weakened AAA wall from the pulsatile pressure and, hence, possible rupture. In this paper, we propose a framework to estimate the wall stress distribution of non-stented/stented AAA based on fluid-structure interaction, which is utilized in a surgical simulation system (IRAS). The 3D geometric model of AAA is reconstructed from computed tomography angiographic (CTA) images. Based on our experiments, a combined logarithm and polynomial strain energy equation is applied to model the elastic properties of arterial wall. The blood flow is modeled as laminar, incompressible, and non-Newtonian flow by applying Navier-Stokes equation. The obtained pressure of blood flow is applied as load on the AAA meshes with and without stent-graft and the wall stress distribution is calculated by fluid-structure interaction (FSI) solver equipped in ANSYS. Experiments demonstrate that our analytical results are consistent with clinical observations.
authors.affiliation: Department of Mechanical Engineering, National University of Singapore.
authors.forename: Jing
authors.initials: J
authors.lastname: Qin
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Chee-Kong
authors.initials: CK
authors.lastname: Chui
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Huang
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.forename: Wai-Man
authors.initials: WM
authors.lastname: Pang
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Sudhakar
authors.forename: Stephen
authors.initials: S
authors.lastname: Chang
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000503:physiopathology* / Q000601:surgery*; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001807:Blood Vessel Prosthesis; D003198:Computer Simulation; D055119:Elastic Modulus; D006801:Humans; D008955:Models, Cardiovascular; D033081:Shear Strength; D015607:Stents; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed