Ultrasonic Quantitative Imaging with a Ring Array for Breast Examination

Abstract

An alternative approach to echographic breast imaging can be found in computerized transaxial tomography which can provide quantitative cross sectional images for various bulk acoustic parameters pertaining to the tissue. The first ultrasonic tomograms have been recorded in-vitro by Greenleaf et al. (1) and laterly in-vivo (2). In order to eliminate mechanical scanning effects in tomographic data recordings, an immobile 360° ring array has been proposed (3,4). The system architecture for electronic steering and scanning such an array has been described adopting “constant-K” mode of scanning (5). In this paper, we report the manufacturing technique for a 450 element toroidal ring array which has been built, as well as its experimental acoustic properties. We will also compare the ray displacement effects, due to refraction at a breast interface, for both a ring and linear array.