The ultrasound macroscope: initial studies of breast tissue.

A system called the ultrasound macroscope has been developed to measure the ultrasonic properties of tissues. Based on the concept of the scanning acoustic microscope, it is capable of generating quantitative images of ultrasound velocity, attenuation and backscatter for macroscopic slices of tissue. By maintaining high resolution (approximately 120 microns at 13 MHz) the morphology of complex tissues is well delineated. Data from regions of interest in the tissue are transformed into three dimensional probability distributions representative of the tissue's ultrasonic characteristics. Sets of two dimensional projections of these distributions are used to display the information. As an initial study, the properties of breast tissues are analyzed. Examples of both normal and abnormal pathology are presented and the relevance of the results to clinical imaging are discussed.