ImSonic Contrast Resonance Sequence (CRS) Imaging uses Imsonic proprietary technology that can always resonate the microbubbles in the circulation system. The received contrast responses mainly depend on the resonant response from the microbubbles, immune to the environment and ultrasound pathway. This is particularly helpful when the ultrasound pathway in front of the tumor has been heated up by HIFU therapy so that tissue acoustic / elastic characterization has changed or hyperechoic vapor effect starts to dominate during and immediately after the HIFU treatment.