A novel imaging approach utilizing microwave scattering was proposed in order to analyze various\nproperties of bone. Microwave frequencies of 900 MHz, 1 GHz, and 2.4 GHz were used during this\nstudy. This investigation�s objectives were to emphasize characteristics of abnormalities in human\nbones and to detect fine fractures through contrasts in bone density. The finite element method\n(FEM) presented here is generated from COMSOL software at different frequencies. The study identified\nthe optimum transmission directed at the interface layers from an external microwave source.\nIt was found that approximately 900 MHz microwave power was ideal for this application. This can\nbe attributed to the penetration depth where the power dissipation is analyzed based on bone condition.\nThe microwave energy was generated from an exterior antenna that was interfaced, via catheter,\nto skeletal bone. The power transmitted to bone was converted into thermal energy, and has\nled to a visible temperature distribution pattern, which reflects the bone density level, and accordingly,\nthe type of bone under investigation. The electrical and thermal properties, including the dielectric\npermittivity, thermal conductivity, and heat flux absorption through the bone substance,\nhave great implications on the FEM distribution. The boundary conditions using tangential matching\nof field components at the tissue-bone interface were incorporated into the finite element method.\nThe average power from the electromagnetic fields (estimated from the Poynting�s vector, P = E*H),\nwas assumed to be fully absorbed as heat due to the conductivity of the bone material. Furthermore,\nmicrowave energy was applied as a delta function and the thermal distributions have been analyzed\nin order to distinguish between normal healthy bone and bones with structural or metabolic abnormalities.\nThe latter was emulated by different bone density to contrast normal bone anatomy.\nThe FEM simulation suggests that thermography microwave imaging could be a good tool for bone\ncharacterization in order to detect skeletal abnormalities. This approach could be advantageous\nover other existing methods such as X-ray imaging.
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