High-Intensity Focused Ultrasound Ablation Monitoring Using Ultrafast Doppler Imaging: A Preliminary Study

High-intensity focused ultrasound (HIFU) has emerged as a promising and noninvasive technique for localized thermal ablation of pathological tissue. Ultrasound-based monitoring of HIFU treatments has been developed by detecting echogenicity changes induced by cavitation. However, due to the low contrast between the lesion and surrounding tissue, for instance, ablation may occur in the absence of significant bubble generation, there is still a high request for developing more sensitive monitoring methods. Ultrafast ultrasound Doppler imaging has advantages in monitoring HIFU treatment due to its superior spatiotemporal resolution and heightened sensitivity for small vessels. In this study, we present a synchronized protocol that harmonizes HIFU exposure with an ultrafast acquisition sequence. The proposed method was demonstrated on the rat cerebral cortex ablation, enabling simultaneous visualization of hemodynamic changes and small vasculature disruption during the HIFU treatment. Ultrafast Doppler monitoring holds the potential to improve the safety and accuracy of HIFU treatments, thereby promoting its broader clinical adoption and utilization.