2-D FFT for Periodic Noise Removal on Strain Image & &

Abstract-Elastography is a non-invasive method in which stiffness of soft tissue is displayed as strain images to assist in detecting or classifying tumors. External tissue compression causes axial displacements which are subsequently computed and converted to strain. However, in this processing, periodic artifacts often corrupt the image quality severely. This paper presents a 2-D FFT removal algorithm for reducing such artifacts in ultrasonic strain imaging. Because the periodic pattern of the artifacts, we apply the 2-D FFT in the strain image to extract and remove the peaks which are corresponding to artifacts in the frequency domain. Computer simulations and in vitro testing demonstrate our proposed method performs quite well in removing strain image artifacts.