Differences in the attenuation of ultrasound by normal, benign, and malignant breast tissue.

In quantitative measurements of the attenuation of ultrasound in 18 samples of variously normal, benign, and malignant breast tissue, we found significantly different ranges of attenuation. As observed in previous in vivo studies, with the exception of medullary carcinoma, malignant tissue produces the most attentuation of ultrasound in the frequency range of 1.5 to 3.0 MHz we employed. The apparatus, measurement method, results, and the possible causes of the differences in attenuation are presented.