Ultrasonic speed of sound dispersion imaging.

The feasibility for speed of sound dispersion (SOSD) imaging was investigated here. A through transmission new method for measuring the SOSD was utilized. With this method a long pulse comprising of two frequencies one being the double of the other is transmitted through the object and detected on its other side. SOSD projection images were obtained by scanning objects immersed in water using a raster mode utilizing a computerized scanning system. Using this approach SOSD projection images were obtained for solids and fluids as well as for a tissue mimicking breast phantom and an in vitro soft tissues phantom. The results obtained here, have clearly demonstrated the feasibility of SOSD projection imaging. SOSD may serve as a new contrast source and potentially may aid in breast diagnosis.