title: A hybrid FDTD-Rayleigh integral computational method for the simulation of the ultrasound measurement of proximal femur.
abstract: The development of novel quantitative ultrasound (QUS) techniques to measure the hip is critically dependent on the possibility to simulate the ultrasound propagation. One specificity of hip QUS is that ultrasounds propagate through a large thickness of soft tissue, which can be modeled by a homogeneous fluid in a first approach. Finite difference time domain (FDTD) algorithms have been widely used to simulate QUS measurements but they are not adapted to simulate ultrasonic propagation over long distances in homogeneous media. In this paper, an hybrid numerical method is presented to simulate hip QUS measurements. A two-dimensional FDTD simulation in the vicinity of the bone is coupled to the semi-analytic calculation of the Rayleigh integral to compute the wave propagation between the probe and the bone. The method is used to simulate a setup dedicated to the measurement of circumferential guided waves in the cortical compartment of the femoral neck. The proposed approach is validated by comparison with a full FDTD simulation and with an experiment on a bone phantom. For a realistic QUS configuration, the computation time is estimated to be sixty times less with the hybrid method than with a full FDTD approach.
authors.affiliation: Laboratoire d'Imagerie Paramétrique, UPMC Univ Paris 06, CNRS UMR 7623, ESPCI ParisTech, 15 rue de l'Ecole de Médecine, 75006 Paris, France. Electronic address: didier.cassereau@upmc.fr.
authors.forename: Didier
authors.initials: D
authors.lastname: Cassereau
authors.affiliation: Laboratoire d'Imagerie Paramétrique, UPMC Univ Paris 06, CNRS UMR 7623, 15 rue de l'Ecole de Médecine, 75006 Paris, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Nauleau
authors.affiliation: Institut Langevin, CNRS UMR 7587, ESPCI ParisTech, INSERM ERL U979, Université Denis Diderot-Paris7, 1 rue Jussieu, 75005 Paris, France.
authors.forename: Aniss
authors.initials: A
authors.lastname: Bendjoudi
authors.affiliation: Laboratoire d'Imagerie Paramétrique, UPMC Univ Paris 06, CNRS UMR 7623, 15 rue de l'Ecole de Médecine, 75006 Paris, France.
authors.forename: Jean-Gabriel
authors.initials: JG
authors.lastname: Minonzio
authors.affiliation: Laboratoire d'Imagerie Paramétrique, UPMC Univ Paris 06, CNRS UMR 7623, 15 rue de l'Ecole de Médecine, 75006 Paris, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Laugier
authors.affiliation: Institut Langevin, CNRS UMR 7587, ESPCI ParisTech, INSERM ERL U979, Université Denis Diderot-Paris7, 1 rue Jussieu, 75005 Paris, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Bossy
authors.affiliation: Laboratoire d'Imagerie Paramétrique, UPMC Univ Paris 06, CNRS UMR 7623, 15 rue de l'Ecole de Médecine, 75006 Paris, France.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Grimal
mesh_terms: D000465:Algorithms; D015519:Bone Density; D003198:Computer Simulation; D005272:Femur Neck / Q000000981:diagnostic imaging*; D006801:Humans; D019047:Phantoms, Imaging; D012542:Scattering, Radiation; D014159:Transducers; D014463:Ultrasonography
keywords: DORT method; Femoral neck; Guided waves; Semi-analytic; Simulation