Diagnostic ultrasound image subtraction based HIFU effect estimation method by using wavelet decomposition coefficient energy

This study tests the hypothesis that the effect of High-Intensity Focused Ultrasound (HIFU) can be correlated with the texture feature of general ultrasound image subtraction (USIS). Porcine muscle was chosen as in-vitro sample. Tissue's ultrasound images and their relative temperature values were caught during experiment. We calculate the wavelet decomposition coefficient energy (WDCE) of USIS of the HIFU lesion area to analysis texture features at different temperature. The statistical results show that WDCE elevates linearly with the temperature especially under 65°C. We still analyzed the WDCE of rotation-invariant subbands. Between 40°C to 65°C, the subband WDCEs elevate linearly with temperature, but they will not change much above 65°C. So we get a conclusion that WDCE can be used as a parameter for estimating the temperature during HIFU treatment and subband WDCEs are helpful to monitor the HIFU effect non-invasively.