Combination of high-intensity focused ultrasound with nanoscale ultrasound contrast agent in treatment of rabbit breast VX2 tumors: a pilot study

To demonstrate ultrasound contrast agents to be important potentiators of high-intensity focused ultrasound (HIFU), we prospectively assessed the effectiveness of HIFU combined with nanoscale ultrasound contrast agents for the treatment of breast VX2 tumors in rabbits. We found that the change of grayscale value in the target area in the HIFU+nanobubble group was significantly higher than that in the HIFU+phosphate-buffered saline (PBS) group after irradiation (P<.01). The size of coagulation necrosis was also significantly larger in the HIFU+nanobubble group when compared to that in the HIFU+PBS group (P<.001). In conclusion, our study suggested that adding nanoscale ultrasound contrast agents may improve the treatment efficacy of HIFU for breast VX2 tumors in rabbits.