Specular echo imaging with spectral correlation

The presence of small specular scatterers in biological tissue gives rise to coherent echoes masked by diffuse scattering, which is present throughout the tissue. In tissues such as breast, the detection of small specular scatterers is important for identifying certain malignant neoplasm's or microcalcifications found in malignant tumors. This paper demonstrates the use of the generalized spectrum for quantifying the specularity of the scattering in each resolution cell, independent of echo intensity. Parametric images are obtained by computing specular-to-diffuse ratios from the generalized spectra of each resolution cell. Variations in this ratio are used to identify distinct rf echo patterns caused by malignant tumors in breast tissue. High ratio values are observed near malignant tumor locations, while low values are observed for benign tumors (cysts and fibroadenomas) and normal tissue locations.