Monitoring HIFU thermal damage based on differential acoustic radiation force pulse imaging

High intensity focused ultrasound (HIFU) is widely used in the treatment of benign and malignant tumors. However, image monitoring remains a key challenge for precise treatment in clinical applications. The aim of this study is to validate the feasibility of the Acoustic radiation force impulse (ARFI) method for monitoring and assessing HIFU thermal damage, thus providing a more reliable method for clinical treatment monitoring. In this study, a HIFU damage monitoring system was constructed based on ARFI imaging. Before and after HIFU ablation, transient acoustic radiation force is employed to stimulate the focal tissue to generate motion, which was then detected with ultrafast ultrasound imaging. Finally, the two-dimensional motion images obtained before and after treatment were differentiated. The results demonstrate that after HIFU ablation, the increased stiffness of the damage region manifested as greater displacement, resulting in displacement differential images. In addition, the damage region in the differential ARFI image has a better match with the hyperechoic region in the ultrasound image, and has higher damage contrast and clearer damage boundaries, suggesting that the differential ARFI image can better reflect the tissue damage and has the potential to provide a more accurate monitoring method for the assessment of clinical HIFU thermal damage.