Improvement on the elastic visualization of thermal lesion using block wavelet shrinkage

We proposed a method of block wavelet shrinkage (BW-Shrink) to improve the strain visualization of microwave-induced lesion by denoising the estimated displacements. The proposed method adaptively approaches the elastogrpahic noise distribution by applying wavelet shrinkage in group of local blocks respectively. The blocks are conjunctive to each other to cover the whole region of interest (ROI). In vitro experiments on porcine livers show that the signal-to-noise ratio (SNRe) and the contrast-to-noise ratio (CNRe) are significantly improved (more than 5-dB) while the lesion edges are well preserved. Also, the lesion sizes measured from the elastograms and the morphological samples show strong consistency.