A Review of High-Intensity Focused Ultrasound in Urology.

This review provides an introduction to high-intensity focused ultrasound (HIFU) and reviews its historical and current use in urological surgery. Current and historical literature (1927-2020), including that describing trials and review articles in the medical and ultrasonic literature, has been reviewed, using Pub Med and Cochrane search engines. HIFU is currently one of a number of treatments for prostate cancer, both as a primary treatment that can be repeated, and as a salvage treatment post-radiotherapy. HIFU is not yet sufficiently mature to be a standard treatment for renal cancer or other urological diseases, although there has been some success in early clinical trials. As the technology improves, this situation is likely to change. HIFU has been understood as a concept for a century, and has been applied in experimental use for half that time. It is now an accepted treatment with low morbidity in many diseases outside the scope of this review. In urological surgery, prostate HIFU is accepted as a localised treatment in selected cases, with potentially fewer side effects than other localised therapies. Currently the treatment for renal cancer is hindered by the perinephric fat and the position of the kidneys behind the ribs; however, as the technology improves with image fusion, faster treatments, and the ability with phased array transducers and motion compensation to overcome the problems caused by the ribs and breathing, successful treatment of kidney tumours will become more of a reality. In due course, there will be a new generation of machines for treating prostate cancer. These devices will further minimise the side effects of radical treatment of prostate cancer.