MR-Guided High-Intensity Focused Ultrasound: Current Status of an Emerging Technology

The concept of ideal tumor surgery is to remove the neoplastic tissue without damaging adjacent normal structures. High-intensity focused ultrasound (HIFU) was developed in the 1940s as a viable thermal tissue ablation approach. In clinical practice, HIFU has been applied to treat a variety of solid benign and malig- nant lesions, including pancreas, liver, prostate, and breast carcinomas, soft tissue sarcomas, and uterine fibroids. More recently, magnetic resonance guidance has been applied for treatment monitoring during focused ultrasound procedures (magnetic resonance–guided focused ultra- sound, MRgFUS). Intraoperative magnetic resonance imaging provides the best possible tumor extension and dynamic control of energy deposition using real-time magnetic resonance imaging thermometry. The lecture will introduce the fundamental principles of the MRgFUS technique reporting application and personal outcomes in the local control of bone metastasis and osteoid osteoma, and in the treatment of breast, prostate, liver and pancreas cancer.