Dynamic quantitative ultrasound imaging of mimicked breast lesions during shear wave propagation to emphasize differences in tissue statistical backscatter properties

Abstract

The main motivation was to increase the accuracy of the breast tissue characterization by combining quantitative ultrasound (QUS) with ultrasound (US) dynamic elastography. An agar-gelatin breast mimicking phantom with two inclusions containing the same density of agar (US scatterers) but different proportions of gelatin corresponding to different mechanical properties was made. Transient plane shear waves (SW) at 200 Hz were transmitted through the phantom while the displacement of scatterers was imaged at 5 MHz with an ultrafast imaging technique. From segmented inclusions, the reciprocal of the effective density of scatterers of a general distribution model of the echo envelope and its normalized range were estimated for each inclusion. The results showed that the relative difference of magnitudes between the surrounding medium and both inclusions A and B were 65.4% (A) and 6.4% (B), respectively, whereas differences (in %) of the normalized range (under SW propagation) were 35.3% (A) and 35.1% (B), respectively. The static value could barely distinguish inclusion B from the surrounding; however, the dynamic range of succeeded in that task for both inclusions. Thus, dynamic QUS might add information to QUS performed traditionally in a static framework. © 2013 Acoustical Society of America.