Cancellous and cortical bone imaging by reflected tomography

This paper deals with the inverse scattering problem observed when ultrason ic waves are used to analyze biological media. The objective is to image ca ncellous and cortical bone by ultrasonic reflected tomography (URT). Becaus e strong contrast and high absorbance bodies such as bones cannot be imaged at usual ultrasonic high frequencies (>1 MHz), we adapted for low-frequenc y URT (< 1MHz) our tomographic set-up and reconstruction and acquisition to ols, previously developed for weakly scattered media. Indeed, when the freq uency of the transducer decreases, the penetration length of the wave incre ases, which unfortunately makes resolution poor, inappropriate for bone ima gery. To improve resolution, we extend the generalized inversion in the com plementary bandwidth of the electro-acoustic set-up (Papoulis deconvolution ). This resolution enhancement for human porous vertebrae and human and ani mal femur showed that high-resolution images can be obtained with low-frequ ency URT.