Anthropomorphic phantoms for assessing systems used in ultrasound imaging of the compressed breast.

Two anthropomorphic phantoms, simulating the breast as it is compressed against the chest wall during ultrasonic imaging, are described in detail regarding structural configurations and distributions of ultrasonic properties. The external shape of each phantom is that of a rectangular parallelepiped; this simple shape is consistent with the breast in the compressed configuration and also facilitates the inclusion of a considerable variety of simulated lesions including comparisons of imaging as a function of depth. One of the phantoms was completed about 4 1/2 years prior to this writing, and images made with scanners which were state-of-the-art in late 1983 and 1984 are compared with images made with two current state-of-the-art imagers. Improvements in imager quality over that period are apparent. The more recently produced phantom contains a simulated tumor with a complex structure as well as realistic simulated calcifications of various sizes. The tumor has a necrotic core and an irregularly shaped boundary. This boundary possesses a roughness intended to give rise to diffuse reflection.