 scale manifest as noticeable edges in the ultrasound image. At a microscopic level, there is also a difference in the acoustic properties between the cells and the extra cellular matrix in which they preside. Diffusive scattering from heterogeneities on this scale ultimately results in the speckle pattern that is characteristic of ultrasound images. (The speckle pattern is created by the constructive and destructive interference of spatial and temporal variations in these reflections. The exact speckle pat