Ultherapy : Firm and Lift the skin without surgery using HIFU. High intensity focused ultrasound (HIFU) is an early stage medical technology that is in various stages of development worldwide to treat a range of disorders. The mechanism is similar to using a magnifying glass to focus sunlight. Focused ultrasound uses an acoustic lens to concentrate multiple intersecting beams of ultrasound on a target. Each individual beam passes through tissue with little effect but at the focal point where the beams converge, the energy can have useful thermal or mechanical effects. HIFU is typically performed with real-time imaging via ultrasound or MRI to enable treatment targeting and monitoring (including thermal tracking with MRI).