Hello! Thank you for your question. Ulthera is the device, as Ultherapy is the treatment. HIFU stands for high-intensity focused ultrasound. A form of HIFU is used with Ulthera- MFU, which stands for micro-focused ultrasound technology. The Ulthera system is a FDA approved, non-invasive aesthetic treatment, that uses MFU for skin lifting and tightening. It combines MFU with high resolution ultrasound imaging, so that the practitioner can see the layers of tissue and make sure that the energy is being delivered to the correct layer to produce the desired result. I recommend that you consult with an experienced practitioner to see if it is an appropriate treatment for you..