Direct measurement of sound velocity in various specimens of breast tissue

RATIONALE AND OBJECTIVES. Previous studies using ultrasound CT or clinical amplitude/velocity reconstruction imaging ultrasound may indicate that canc ers differ from normal breast tissue by increased sound velocity. However, only limited experience with direct measurements of sound velocity exists. This study aimed to investigate sound velocity measured directly in a varie ty of breast specimens. METHODS. Sound velocity was measured directly by forceps in fresh breast sp ecimens chosen to contain one type of tissue only. Eighty specimens (31 can cers, 18 benign changes of glandular/fibrous tissue, 22 fatty tissues, 5 fi broadenomas, 2 compound tissues, 1 phylloides tumor, and 1 inflammation) we re analyzed. RESULTS. Ultrasound velocities in carcinoma, benign changes, fibroadenoma, inflammation, and the phylloides tumor were very similar, with almost compl ete overlap. In contrary, the ultrasound velocity of fatty tissue was signi ficantly lower. Compound tissues containing fat had an intermediate sound v elocity. CONCLUSIONS. Sound velocity may add complementary information to echogenici ty (B-scan). Because fat lobules exhibit low ultrasound velocity and carcin omas do not, a locally exact combination of ultrasound velocity information and reflexivity information should allow improved breast cancer detection by ultrasound.