title: Assessment of the fundamental flexural guided wave in cortical bone by an ultrasonic axial-transmission array transducer.
abstract: The fundamental flexural guided wave (FFGW), as modeled, for example, by the A0 Lamb mode, is a clinically useful indicator of cortical bone thickness. In the work described in this article, we tested so-called multiridge-based analysis, based on the crazy climber algorithm and short-time Fourier transform, for assessment of the FFGW component recorded by a clinical array transducer featuring a limited number of elements. Methods included numerical finite-element simulations and experiments in bone phantoms and human radius specimens (n = 41). The proposed approach enabled extraction of the FFGW component and determination of its group velocity. This group velocity was in good agreement with theoretical predictions and possessed reasonable sensitivity to cortical width (r(2) = 0.51, p < 0.001) in the in vitro experiments. It is expected that the proposed approach enables related clinical application. Further work is still needed to analyze in more detail the challenges related to the impact of the overlying soft tissue.
authors: Department of Physics, University of Jyväskylä, Jyväskylä, Finland. warma@iki.fi
authors: Vantte
authors: V
authors: Kilappa
authors: Kailiang
authors: K
authors: Xu
authors: Petro
authors: P
authors: Moilanen
authors: Erkki
authors: E
authors: Heikkola
authors: Dean
authors: D
authors: Ta
authors: Jussi
authors: J
authors: Timonen
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D019220:High-Energy Shock Waves; D006801:Humans; D008027:Light; D008954:Models, Biological; D011884:Radius / Q000000981:diagnostic imaging* / Q000502:physiology*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation*