title: A versatile and experimentally validated finite element model to assess the accuracy of shear wave elastography in a bounded viscoelastic medium.
abstract: The feasibility of shear wave elastography (SWE) in arteries for cardiovascular risk assessment remains to be investigated as the artery's thin wall and intricate material properties induce complex shear wave (SW) propagation phenomena. To better understand the SW physics in bounded media, we proposed an in vitro validated finite element model capable of simulating SW propagation, with full flexibility at the level of the tissue's geometry, material properties, and acoustic radiation force. This computer model was presented in a relatively basic set-up, a homogeneous slab of gelatin-agar material (4.35 mm thick), allowing validation of the numerical settings according to actual SWE measurements. The resulting tissue velocity waveforms and SW propagation speed matched well with the measurement: 4.46 m/s (simulation) versus 4.63 ± 0.07 m/s (experiment). Further, we identified the impact of geometrical and material parameters on the SW propagation characteristics. As expected, phantom thickness was a determining factor of dispersion. Adding viscoelasticity to the model augmented the estimated wave speed to 4.58 m/s, an even better match with the experimental determined value. This study demonstrated that finite element modeling can be a powerful tool to gain insight into SWE mechanics and will in future work be advanced to more clinically relevant settings.
authors.forename: Annette
authors.initials: A
authors.lastname: Caenen
authors.forename: Darya
authors.initials: D
authors.lastname: Shcherbakova
authors.forename: Benedict
authors.initials: B
authors.lastname: Verhegghe
authors.forename: Clément
authors.initials: C
authors.lastname: Papadacci
authors.forename: Mathieu
authors.initials: M
authors.lastname: Pernot
authors.forename: Patrick
authors.initials: P
authors.lastname: Segers
authors.forename: Abigaïl
authors.initials: A
authors.lastname: Swillens
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000295:instrumentation / Q000379:methods* / Q000592:standards*; D020342:Finite Element Analysis; D008954:Models, Biological; D019047:Phantoms, Imaging; D014783:Viscosity