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High intensity focused ultrasound (HIFU, or sometimes MRgFUS for magnetic resonance guided focused ultrasound) is a medical procedure that applies high intensity focused ultrasound energy to locally heat and destroy diseased or damaged tissue through ablation. HIFU is a hyperthermia therapy, a class of clinical therapies that use temperature to treat diseases. HIFU is also one modality of therapeutic ultrasound, involving minimally invasive or non-invasive methods to direct acoustic energy into the body. In addition to HIFU, other modalities include ultrasound-assisted drug delivery, ultrasound hemostasis, ultrasound lithotripsy, and ultrasound-assisted thrombolysis. Clinical HIFU procedures are typically performed in conjunction with an imaging procedure to enable treatment planning and targeting before applying a therapeutic or ablative levels of ultrasound energy. When Magnetic Resonance Imaging (MRI) is used for guidance, the technique is sometimes called Magnetic Resonance guided Focused Ultrasound, often shortened to MRgFUS or MRgHIFU. Currently, HIFU is an approved therapeutic procedure to treat uterine fibroids in Asia, Australia, Canada, Europe, Israel and the United States. HIFU is approved for use in Bulgaria, China, Hong Kong, Germany, Italy, Japan, Korea, Malaysia, Mexico, Poland, Russia, Romania, Spain and the United Kingdom. Research for other indications is actively underway, including clinical trials evaluating the effectiveness of HIFU for the treatment of cancers of the brain, breast, liver, bone, prostate, as well as soft tissue tumors. At this time non-image guided HIFU devices are cleared to be on the market in the US, Canada, EU, Australia, and several countries in Asia for the purposes of body sculpting. ==Medical uses== Therapeutic applications use ultrasound to bring heat or agitation into the body. Therefore, much higher energies are used than in diagnostic ultrasound. In many cases the range of frequencies used are also very different. *Ultrasound sources may be used to generate regional heating and mechanical changes in biological tissue, e.g. in occupational therapy, physical therapy and cancer treatment. However the use of ultrasound in the treatment of musculoskeletal conditions has fallen out of favor. *Focused ultrasound may be used to generate highly localized heating to treat cysts and tumors (benign or malignant), This is known as Magnetic Resonance guided Focused Ultrasound (MRgFUS) or High Intensity Focused Ultrasound (HIFU). These procedures generally use lower frequencies than medical diagnostic ultrasound (from 0.250 to 2 MHz), but significantly higher energies. HIFU treatment is often guided by MRI. *Focused ultrasound may be used to break up kidney stones by lithotripsy. *Ultrasound may be used for cataract treatment by phacoemulsification. *Additional physiological effects of low-intensity ultrasound have recently been discovered, e.g. its ability to stimulate bone-growth and its potential to disrupt the blood–brain barrier for drug delivery. *Procoagulant at 5–12 MHz 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「High-intensity focused ultrasound」の詳細全文を読む スポンサード リンク
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