1. An ultrasonic imaging method for ultrasonic imaging of tissues located in a tissue image region including a contrast agent in at least a portion of said tissue image region, said method comprising the steps of: (a) projecting an ultrasound beam into said tissue image region; (b) receiving ultrasound reflections from said tissue image region and transducing said reflections into corresponding electrical echo signals; (c) first processing said electrical echo signals to derive a plurality of frequency component signals, each frequency component signal representing an electrical echo signal parameter associated with a pre-determined frequency component of said electrical echo signals; (d) second processing said plural frequency component signals to combine them into a single enhanced contrast image data signal; (e) repeating steps (a) through (d) to derive an ordered array of enhanced contrast image data signals representing an image of said tissue image region; and (f) displaying said ordered array of enhanced contrast image data signals as a visual image of said tissue image region.