Correction of the artifact of the intensity distortion in the ultrasonic B-mode imaging with a phase insensitive method

The intensity distortion appearing as acoustical shadowing and intensity enhancements is a well known artifact in some areas behind curved objects in ultrasonic B-mode imaging. Assuming phase cancellation effects, the authors investigated these phenomena with the phase insensitive imaging method. A tissue-mimicking phantom was made especially for this study. The echoes for each emitting position were sampled separately within a receiving array by using a specially designed recording system. These A-scan signals were processed with the phase insensitive method and then used to generate a B-mode image. By comparison of this image to the conventional image, it was revealed that the acoustical shadowing is caused mostly by the phase cancellation effects. Furthermore, the phase insensitive signal processing reduces the speckles in the image. This discovery will be of great interest for ultrasonic tissue characterization