title: The finite element method for micro-scale modeling of ultrasound propagation in cancellous bone.
abstract: Quantitative ultrasound for bone assessment is based on the correlations between ultrasonic parameters and the properties (mechanical and physical) of cancellous bone. To elucidate the correlations, understanding the physics of ultrasound in cancellous bone is demanded. Micro-scale modeling of ultrasound propagation in cancellous bone using the finite-difference time-domain (FDTD) method has been so far utilized as one of the approaches in this regard. However, the FDTD method accompanies two disadvantages: staircase sampling of cancellous bone by finite difference grids leads to generation of wave artifacts at the solid-fluid interface inside the bone; additionally, this method cannot explicitly satisfy the needed perfect-slip conditions at the interface. To overcome these disadvantages, the finite element method (FEM) is proposed in this study. Three-dimensional finite element models of six water-saturated cancellous bone samples with different bone volume were created. The values of speed of sound (SOS) and broadband ultrasound attenuation (BUA) were calculated through the finite element simulations of ultrasound propagation in each sample. Comparing the results with other experimental and simulation studies demonstrated the capabilities of the FEM for micro-scale modeling of ultrasound in water-saturated cancellous bone.
authors.affiliation: Faculty of Engineering, Civil and Environmental Engineering Department, 3-016 Markin/CNRL Natural Resources Engineering Facility, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: vafaeian@ualberta.ca.
authors.forename: B
authors.initials: B
authors.lastname: Vafaeian
authors.affiliation: Faculty of Engineering, Civil and Environmental Engineering Department, 3-016 Markin/CNRL Natural Resources Engineering Facility, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: elrich@ualberta.ca.
authors.forename: M
authors.initials: M
authors.lastname: El-Rich
authors.affiliation: Faculty of Medicine and Dentistry, 7-020D Katz Group Centre for Pharmacy and Health Research, University of Alberta, Edmonton, Alberta T6G 2E1, Canada. Electronic address: telbialy@ualberta.ca.
authors.forename: T
authors.initials: T
authors.lastname: El-Bialy
authors.affiliation: Faculty of Engineering, Civil and Environmental Engineering Department, 3-016 Markin/CNRL Natural Resources Engineering Facility, University of Alberta, Edmonton, Alberta T6G 2W2, Canada. Electronic address: adeeb@ualberta.ca.
authors.forename: S
authors.initials: S
authors.lastname: Adeeb
mesh_terms: D015519:Bone Density / Q000502:physiology*; D003198:Computer Simulation; D020342:Finite Element Analysis; D006801:Humans; D021621:Imaging, Three-Dimensional; D010024:Osteoporosis / Q000000981:diagnostic imaging*; D011884:Radius / Q000000981:diagnostic imaging*; D014159:Transducers; D014463:Ultrasonography; D014867:Water
chemical_list: D014867:Water
keywords: Broadband ultrasound attenuation; Cancellous bone; Finite element method