Patent ID: 9643030
Date: 2017-05-09
CPC Classifications: A61B,A61N,G16H

Claim:
1. A method for operating a high-intensity focused ultrasound (HIFU) thermal ablation apparatus having functions of integrated temperature estimation and elastography for thermal lesion determination comprising: reconstructing an ultrasound data into raw data using the high-intensity focused ultrasound (HIFU) thermal ablation apparatus; dicing the raw data into a plurality of fragments and using an echo time shift to calculate a shift of every fragment using the high-intensity focused ultrasound (HIFU) thermal ablation apparatus, wherein the raw data comprise 128 signals; using the high-intensity focused ultrasound (HIFU) thermal ablation apparatus to compare the shift of every fragment before and after an application of stress in order to obtain and acquire a temperature image and an elasticity image; and obtaining a strain image including an ultrasound temperature-change image and an ultrasound elasticity-change image by integrating the temperature image and the elasticity image, wherein the ultrasound temperature-change image being defined as a temperature rising effect, the ultrasound elasticity-change image being defined as a displacement caused by the stress, wherein a relationship between a temperature and a time displacement is given by wherein α(z) is a linear coefficient of a thermal expansion of a medium at an axial depth z, being defined as a coefficient of thermally induced sound speed, and T is a temperature, wherein equation (1) is simplified for small temperature changes as wherein k wherein when a tissue undergoing external compression, a longitudinal strain change is estimated comprising the steps: wherein said equation (3) is rearranged as wherein (d simplifying said equation (1), said equation (2), said equation (3), and said equation (4), to a statement that a derivative of the time shift being proportional to an external compression as wherein strain changes presented in said equation (2) and said equation (5) being based on the echo time shifts, which is estimated by computing a 1-D cross-correlation on paired RF A-lines, wherein said strain changes are calculated using a numerical derivative of said time shifts as