 High intensity focused ultrasound HIFU is a form of IGTA that needs no skin incision or needle insertion and so, is a truly noninvasive treatment. Under USG guidance, it is able to cause irreversible tissue destruction deep to the skin and subcutaneous layer. Apart from being non-invasive, it is less dependent on the operators skill as the treatment could be controlled by an automated program. In fact, HIFU is highly successful in a number of solid cancers. In the thyroid, it induces tissue damage via the cavitation and thermal effects. To date, several groups including us have confirmed that HIFU ablation is highly effective in inducing shrinkage of benign thyroid nodules. 