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Anthropomorphic breast phantoms for qualification of Investigators for ACRIN Protocol 6666.

The purpose of this study was to evaluate various ultrasonic properties of breast phantoms developed for use in qualifying investigators for participation in the American College of Radiology Imaging Network (ACRIN) protocol 6666, "Screening Breast Ultrasound in High-Risk Women." Specifically, a tool was sought to consistently measure the performance of radiology personnel in detecting and characterizing lesions similar to those expected with screening breast ultrasonography (US). The phantoms are equivalent to one another except for the randomization of positions of 14 of the 17 simulated lesions. The lesions differ in depth and ultrasonic properties. Representative values of propagation speed, attenuation, relative echogenicity, and mass density are reported for all tissue-mimicking components. Beam refraction occurs at the interface between the subcutaneous fat layer and the glandular parenchyma and can result in beam distortion artifacts similar to those encountered in clinical breast US.