Numerical simulation of the axial transmission technique for bone evaluation: a probabilistic approach
Résumé
The axial transmission technique is dedicated to cortical bone assessment. Ultrasonic wave velocity in the cortical thickness is measured using a multi element probe. In order to formulate an inverse problem for the measurement of bone elasticity, the sensitivity of the measurements to bone elastic properties must be assessed. A 2D model of the technique is developed which consists of a layer of homogeneous anisotropic solid bounded by two semiinfinite fluid media. A set of acoustic sources and receivers are placed in one fluid medium. The solid which models bone is considered to have random material properties. The measured velocity is predicted based on a finite element analysis taking into account exact fluid-solid interactions. The probability density functions of the random variables modelling each mechanical parameter of bone are derived following the maximum entropy principle. We will present the estimated mean values and confidence regions of the predicted velocity for various dispersion levels of the bone elastic parameters.