Prototype ANAIS : Tomographe ultrasonore pour l'imagerie anatomique du sein. Comparaison avec l'´ echographie

The research in ultrasound tomography conducted by PROPAGATION and IMAGERIE group of the LMA, results in the execution of an ultrasound mammograph : the ANAIS project (ANAtomical Imaging and Interventional System). Ulti- mately, this work aims to characterize breast tissues and to provide an early detection of breast cancer. This system is dedicated for measuring scattered field in reflection and transmission. The physical parameter reconstructed by inverse methods firstly depends on the accuracy of the wave environment interaction model used, and secondly on the acoustic sensors properties. For an inspection to be consistent with the breast anatomy, our group opted for a semi-circular array allowing an examination of each breast lobe. Several reconstruction methods for various acquisition configurations have been developed, as an ellipsoidal back-projection filtered algorithm in near-field. A preliminary work on the calibration of the prototype array allows to incorporate the probe directivity in the reconstruction procedure. The first images of breast phantom depict the abilities of the ultrasound tomograph with regard to conventional echography.