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Kang Il Lee - One of the best experts on this subject based on the ideXlab platform.
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Correlations of the frequency dependence of the ultrasonic backscatter coefficient with the Bone volume fraction and the trabecular thickness in bovine trabecular Bone: Application of the binary mixture model.
The Journal of the Acoustical Society of America, 2019Co-Authors: Kang Il LeeAbstract:The ultrasonic backscatter coefficient and the exponent n (frequency dependence of the backscatter coefficient) were measured in 24 bovine femoral trabecular Bone samples. The binary mixture model for ultrasonic scattering from trabecular Bone was applied to predict the variations of the ultrasound parameters with the Bone volume fraction (BV/TV) and the trabecular thickness (Tb.Th) in trabecular Bone. The backscatter coefficient exhibited significant, positive correlations with the BV/TV (R = 0.82) and the Tb.Th (R = 0.79). In contrast, the exponent n was found to be significantly, negatively correlated with the BV/TV (R = −0.77) and the Tb.Th, (R = −0.71).The ultrasonic backscatter coefficient and the exponent n (frequency dependence of the backscatter coefficient) were measured in 24 bovine femoral trabecular Bone samples. The binary mixture model for ultrasonic scattering from trabecular Bone was applied to predict the variations of the ultrasound parameters with the Bone volume fraction (BV/TV) and the trabecular thickness (Tb.Th) in trabecular Bone. The backscatter coefficient exhibited significant, positive correlations with the BV/TV (R = 0.82) and the Tb.Th (R = 0.79). In contrast, the exponent n was found to be significantly, negatively correlated with the BV/TV (R = −0.77) and the Tb.Th, (R = −0.71).
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Dependences of the attenuation and the backscatter coefficients on the frequency and the porosity in bovine trabecular Bone: Application of the binary mixture model
Journal of the Korean Physical Society, 2012Co-Authors: Kang Il LeeAbstract:The present study aims to investigate the dependences of the attenuation and the backscatter coefficients on the frequency and the porosity in bovine trabecular Bone in vitro. The frequencydependent attenuation and backscatter coefficients were measured in 22 bovine femoral trabecular Bone samples over a frequency range from 1.4 to 3.0 MHz by using a pair of transducers with a diameter of 12.7 mm and a center frequency of 2.25 MHz. The binary mixture model for ultrasonic scattering in trabecular Bone, in which trabecular Bone is assumed to be an isotropic binary mixture composed of a Bone matrix and marrow, was applied to predict the measurements. The experimental results showed that the attenuation and the backscatter coefficients increased with increasing frequency from 1.4 to 3.0 MHz and decreased with increasing porosity from 66.9 to 91.5%. The predictions of the binary mixture model showed good agreements with the measurements, suggesting that scattering may be the dominant attenuation mechanism in dense bovine trabecular Bone at frequencies from 1.4 to 3.0 MHz.
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Dependence of phase velocity on porosity in cancellous Bone: Application of the modified Biot‐Attenborough model
The Journal of the Acoustical Society of America, 2006Co-Authors: Suk Wang Yoon, Kang Il LeeAbstract:This study aims to apply the modified Biot‐Attenborough (MBA) model to predict the dependence of phase velocity on porosity in cancellous Bone. The MBA model predicted that the phase velocity decreases nonlinearly with porosity. The optimum values for input parameters of the MBA model, such as compressional speed cm of solid Bone and phase velocity parameter s2, were determined by comparing the prediction with the previously published measurements in human calcaneus and bovine cancellous Bones. The value of the phase velocity parameter s2=1.23 was obtained by curve fitting to the experimental data only for 53 human calcaneus samples with a compressional speed cm=2500 m/s of solid Bone. The root‐mean‐square error (rmse) of the curve fit was 15.3 m/s. The optimized value of s2 for all 75 cancellous Bone samples (53 human and 22 bovine samples) was 1.42 with the rmse of 55 m/s. The latter fit was obtained by using cm=3200 m/s. Although the MBA model relies on empirical parameters determined from the experime...
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Acoustic wave propagation in bovine cancellous Bone: Application of the Modified Biot–Attenborough model
The Journal of the Acoustical Society of America, 2003Co-Authors: Kang Il Lee, Heui-seol Roh, Suk Wang YoonAbstract:Acoustic wave propagation in bovine cancellous Bone is experimentally and theoretically investigated in the frequency range of 0.5–1 MHz. The phase velocity, attenuation coefficient, and broadband ultrasonic attenuation (BUA) of bovine cancellous Bone are measured as functions of frequency and porosity. For theoretical estimation, the Modified Biot–Attenborough (MBA) model is employed with three new phenomenological parameters: the boundary condition, phase velocity, and impedance parameters. The MBA model is based on the idealization of cancellous Bone as a nonrigid porous medium with circular cylindrical pores oriented normal to the surface. It is experimentally observed that the phase velocity is approximately nondispersive and the attenuation coefficient linearly increases with frequency. The MBA model predicts a slightly negative dispersion of phase velocity linearly with frequency and the nonlinear relationships of attenuation and BUA with porosity. The experimental results are in good agreement wit...
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Acoustic wave propagation in bovine cancellous Bone: Application of the Modified Biot-Attenborough model.
The Journal of the Acoustical Society of America, 2003Co-Authors: Kang Il Lee, Heui-seol Roh, Suk Wang YoonAbstract:Acoustic wave propagation in bovine cancellous Bone is experimentally and theoretically investigated in the frequency range of 0.5-1 MHz. The phase velocity, attenuation coefficient, and broadband ultrasonic attenuation (BUA) of bovine cancellous Bone are measured as functions of frequency and porosity. For theoretical estimation, the Modified Biot-Attenborough (MBA) model is employed with three new phenomenological parameters: the boundary condition, phase velocity, and impedance parameters. The MBA model is based on the idealization of cancellous Bone as a nonrigid porous medium with circular cylindrical pores oriented normal to the surface. It is experimentally observed that the phase velocity is approximately nondispersive and the attenuation coefficient linearly increases with frequency. The MBA model predicts a slightly negative dispersion of phase velocity linearly with frequency and the nonlinear relationships of attenuation and BUA with porosity. The experimental results are in good agreement with the theoretical results estimated with the MBA model. It is expected that the MBA model can be usefully employed in the field of clinical Bone assessment for the diagnosis of osteoporosis.
A. Lucas-girot - One of the best experts on this subject based on the ideXlab platform.
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Thermal behaviour of composites aluminosilicate-calcium phosphates
Journal of Thermal Analysis and Calorimetry, 2004Co-Authors: A. C. Derrien, H. Oudadesse, Jean-christophe Sangleboeuf, P. Briard, A. Lucas-girotAbstract:A new type of aluminosilicate matrix calcium phosphate crystallites composites (ACPC) was synthesized and studied for osseous Bone Applications. The room temperature synthesis of the aluminosilicate matrix and composites was described. Thermal treatments of compounds allowed the adaptability of some parameters (pH, porosity and mechanical properties). Structure of heat treated composites were characterized by XRD and FTIR. The influence of thermal treatment on the mechanical properties, the porosity and the pH was studied for two temperatures (250 and 500°C). Results evidenced the ability to control the pH, the high level of porosity (»70%) and the good mechanical properties, allowing to consider that ACPC are potential biomaterials for osseous Bone Application.
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Thermal behaviour of composites aluminosilicate-calcium phosphates
Journal of Thermal Analysis and Calorimetry, 2004Co-Authors: A. C. Derrien, H. Oudadesse, Jean-christophe Sangleboeuf, P. Briard, A. Lucas-girotAbstract:A new type of aluminosilicate matrix calcium phosphate crystallites composites (ACPC) was synthesized and studied for osseous Bone Applications. The room temperature synthesis of the aluminosilicate matrix and composites was described. Thermal treatments of compounds allowed the adaptability of some parameters (pH, porosity and mechanical properties). Structure of heat treated composites were characterized by XRD and FTIR. The influence of thermal treatment on the mechanical properties, the porosity and the pH was studied for two temperatures (250 and 500degreesC). Results evidenced the ability to control the pH, the high level of porosity (approximate to70%) and the good mechanical properties, allowing to consider that ACPC are potential biomaterials for osseous Bone Application.
Guillaume Haiat - One of the best experts on this subject based on the ideXlab platform.
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Influence of viscoelastic and viscous absorption on ultrasonic wave propagation in cortical Bone: Application to axial transmission
The Journal of the Acoustical Society of America, 2010Co-Authors: Salah Naili, Quentin Grimal, Maryline Talmant, Christophe Desceliers, Christian Soize, Guillaume HaiatAbstract:Cortical Bone and the surrounding soft tissues are attenuating and heterogeneous media, which might affect the signals measured with axial transmission devices. This work aims at evaluating the effect of the heterogeneous acoustic absorption in Bone and in soft tissues on the Bone ultrasonic response. Therefore, a two-dimensional finite element time-domain method is derived to model transient wave propagation in a three-layer medium composed of an inhomogeneous transverse isotropic viscoelastic solid layer, sandwiched between two viscous fluid layers. The model couples viscous acoustic propagation in both fluid media with the anisotropic viscoelastic response of the solid. A constant spatial gradient of material properties is considered for two values of Bone thicknesses (0.6 and 4 mm). In the studied configuration, absorption in the surrounding fluid tissues does not affect the results, whereas Bone viscoelastic properties have a significant effect on the first arriving signal (FAS) velocity. For a thin Bone, the FAS velocity is governed by the spatially averaged Bone properties. For a thick Bone, the FAS velocity may be predicted using a one-dimensional model.
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Influence of viscoelasticity on the ultrasonic wave propagation in cortical Bone: Application to the axial transmission technique
The Journal of the Acoustical Society of America, 2009Co-Authors: Guillaume Haiat, Salah Naili, Quentin Grimal, Maryline Talmant, Christophe Desceliers, Christian SoizeAbstract:Cortical Bone quality is assessed in clinical practice using axial transmission (AT) devices. Cortical Bone and the surrounding soft tissues are attenuating media, which might affect the results obtained with AT devices. Following the work of in Haiat et al. [J. Acoust. Soc. Am. (2009)] which considers the elastic case, the aim of this work is to evaluate the effect of anisotropic heterogeneous dissipative phenomena occurring in Bone and in soft tissues on the ultrasonic response of the Bone structure. A two‐dimensional finite element time‐domain method is derived to model transient wave propagation in a three‐layer medium composed of an inhomogeneous transverse isotropic viscoelastic (Kelvin–Voigt description) solid layer sandwiched between two dissipative acoustic fluid layers. Bone viscoelasticity is assumed to be heterogeneous and a constant spatial gradient of viscoelastic properties is considered for two values of Bone thicknesses corresponding to relatively thick and thin Bones. The results allow the derivation of a contributing depth (CD) for a thick Bone width. For a gradient of viscoelasticity, CD≅1.6 mm, for a gradient of C11, CD≅0.6 mm, and for a gradient of mass density, CD≅1 mm. [The Agence Nationale de la Recherche (Contract No. no BLAN06‐2 144779) is acknowledged.]
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Influence of a gradient of material properties on ultrasonic wave propagation in cortical Bone: Application to axial transmission.
The Journal of the Acoustical Society of America, 2009Co-Authors: Guillaume Haiat, Salah Naili, Quentin Grimal, Maryline Talmant, Christophe Desceliers, Christian SoizeAbstract:The aim of this work is to evaluate the effect of a spatial gradient of material properties (mass density and stiffness coefficients) of cortical Bone on its ultrasonic response obtained with an axial transmission device. Therefore, a two-dimensional finite element time-domain method is derived to model transient wave propagation in a three-layer medium composed of an inhomogeneous transverse isotropic solid layer sandwiched between two acoustic fluid layers and excited by an acoustic linear source located in one fluid layer, delivering broadband ultrasonic pulses. The model couples the acoustic propagation in both fluid media with the elastodynamic response of the solid layer. A constant spatial gradient of material properties is considered for two values of Bone thicknesses corresponding to relatively thick and thin Bone widths. For a thin Bone (0.6mm) compared to wavelength (around 4mm at 1MHz), the results are in good agreement with a S0 Lamb wave assuming a homogeneous material with spatially average...
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Finite element model of the ultrasonic propagation in cortical Bone: Application to the axial transmission device
2008Co-Authors: Salah Naili, Quentin Grimal, Maryline Talmant, Christophe Desceliers, Christian Soize, Guillaume HaiatAbstract:The axial transmission technique is used clinically for cortical Bone assessment. However, the ultrasonic propagation in this multiscale transverse isotropic medium remains unclear, because of the heterogeneous nature of cortical Bone. At the macroscopic scale, the distribution of porosity induces a gradient of material properties oriented in the radial direction. The aim of this work is to evaluate the effect of a spatial gradient of material properties on the ultrasonic response of a transverse isotropic Bone structure.
A. C. Derrien - One of the best experts on this subject based on the ideXlab platform.
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Thermal behaviour of composites aluminosilicate-calcium phosphates
Journal of Thermal Analysis and Calorimetry, 2004Co-Authors: A. C. Derrien, H. Oudadesse, Jean-christophe Sangleboeuf, P. Briard, A. Lucas-girotAbstract:A new type of aluminosilicate matrix calcium phosphate crystallites composites (ACPC) was synthesized and studied for osseous Bone Applications. The room temperature synthesis of the aluminosilicate matrix and composites was described. Thermal treatments of compounds allowed the adaptability of some parameters (pH, porosity and mechanical properties). Structure of heat treated composites were characterized by XRD and FTIR. The influence of thermal treatment on the mechanical properties, the porosity and the pH was studied for two temperatures (250 and 500°C). Results evidenced the ability to control the pH, the high level of porosity (»70%) and the good mechanical properties, allowing to consider that ACPC are potential biomaterials for osseous Bone Application.
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Thermal behaviour of composites aluminosilicate-calcium phosphates
Journal of Thermal Analysis and Calorimetry, 2004Co-Authors: A. C. Derrien, H. Oudadesse, Jean-christophe Sangleboeuf, P. Briard, A. Lucas-girotAbstract:A new type of aluminosilicate matrix calcium phosphate crystallites composites (ACPC) was synthesized and studied for osseous Bone Applications. The room temperature synthesis of the aluminosilicate matrix and composites was described. Thermal treatments of compounds allowed the adaptability of some parameters (pH, porosity and mechanical properties). Structure of heat treated composites were characterized by XRD and FTIR. The influence of thermal treatment on the mechanical properties, the porosity and the pH was studied for two temperatures (250 and 500degreesC). Results evidenced the ability to control the pH, the high level of porosity (approximate to70%) and the good mechanical properties, allowing to consider that ACPC are potential biomaterials for osseous Bone Application.
Suk Wang Yoon - One of the best experts on this subject based on the ideXlab platform.
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Dependence of phase velocity on porosity in cancellous Bone: Application of the modified Biot‐Attenborough model
The Journal of the Acoustical Society of America, 2006Co-Authors: Suk Wang Yoon, Kang Il LeeAbstract:This study aims to apply the modified Biot‐Attenborough (MBA) model to predict the dependence of phase velocity on porosity in cancellous Bone. The MBA model predicted that the phase velocity decreases nonlinearly with porosity. The optimum values for input parameters of the MBA model, such as compressional speed cm of solid Bone and phase velocity parameter s2, were determined by comparing the prediction with the previously published measurements in human calcaneus and bovine cancellous Bones. The value of the phase velocity parameter s2=1.23 was obtained by curve fitting to the experimental data only for 53 human calcaneus samples with a compressional speed cm=2500 m/s of solid Bone. The root‐mean‐square error (rmse) of the curve fit was 15.3 m/s. The optimized value of s2 for all 75 cancellous Bone samples (53 human and 22 bovine samples) was 1.42 with the rmse of 55 m/s. The latter fit was obtained by using cm=3200 m/s. Although the MBA model relies on empirical parameters determined from the experime...
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Acoustic wave propagation in bovine cancellous Bone: Application of the Modified Biot–Attenborough model
The Journal of the Acoustical Society of America, 2003Co-Authors: Kang Il Lee, Heui-seol Roh, Suk Wang YoonAbstract:Acoustic wave propagation in bovine cancellous Bone is experimentally and theoretically investigated in the frequency range of 0.5–1 MHz. The phase velocity, attenuation coefficient, and broadband ultrasonic attenuation (BUA) of bovine cancellous Bone are measured as functions of frequency and porosity. For theoretical estimation, the Modified Biot–Attenborough (MBA) model is employed with three new phenomenological parameters: the boundary condition, phase velocity, and impedance parameters. The MBA model is based on the idealization of cancellous Bone as a nonrigid porous medium with circular cylindrical pores oriented normal to the surface. It is experimentally observed that the phase velocity is approximately nondispersive and the attenuation coefficient linearly increases with frequency. The MBA model predicts a slightly negative dispersion of phase velocity linearly with frequency and the nonlinear relationships of attenuation and BUA with porosity. The experimental results are in good agreement wit...
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Acoustic wave propagation in bovine cancellous Bone: Application of the Modified Biot-Attenborough model.
The Journal of the Acoustical Society of America, 2003Co-Authors: Kang Il Lee, Heui-seol Roh, Suk Wang YoonAbstract:Acoustic wave propagation in bovine cancellous Bone is experimentally and theoretically investigated in the frequency range of 0.5-1 MHz. The phase velocity, attenuation coefficient, and broadband ultrasonic attenuation (BUA) of bovine cancellous Bone are measured as functions of frequency and porosity. For theoretical estimation, the Modified Biot-Attenborough (MBA) model is employed with three new phenomenological parameters: the boundary condition, phase velocity, and impedance parameters. The MBA model is based on the idealization of cancellous Bone as a nonrigid porous medium with circular cylindrical pores oriented normal to the surface. It is experimentally observed that the phase velocity is approximately nondispersive and the attenuation coefficient linearly increases with frequency. The MBA model predicts a slightly negative dispersion of phase velocity linearly with frequency and the nonlinear relationships of attenuation and BUA with porosity. The experimental results are in good agreement with the theoretical results estimated with the MBA model. It is expected that the MBA model can be usefully employed in the field of clinical Bone assessment for the diagnosis of osteoporosis.