Preclinical ultrasound image-guided high intensity focused ultrasound robot system for breast cancer therapy.

Ultrasound imaging provides real-time feedback for highly accurate positioning and dosing control. In addition, spatial restriction of high-intensity focused ultrasound (HIFU) transducer position in the ultrasound image-guided system is less than that in the case of MRI-guided system. Therefore, wider beam approaching path can be used in the ultrasound image-guided system. To shorten the total treatment time, reducing the cooling time between sonication intervals is essential. Using a wide approach path promotes a reduction in both the cooling time and the risk of heat deposition to the body surface. The array in our preclinical HIFU system is supported by a 5-axis robotic system that enables motion with a pivot fixed at the focal point. In this report, we describe a HIFU beam imaging system that provides highly accurate pivoting motion and coagulation monitoring in real-time for dose control during HIFU treatment.