High Intensity Focused Ultrasound (HIFU)
By using sound waves, the skin and connective tissue that holds skin, muscle, and fat, can trigger tightening through protein denaturation and stimulation of collagen. This device can be used on the face for mild to moderated tightening. The effect can last a year or longer. It usually takes a treatment series of two treatments with little to no downtime.
Topical numbing is used for comfort and nitrous oxide if needed. This is specifically for tightening through stimulation of collagen and elastin production. Full effect is not seen until 6-12 months. Average cost is $500/region around the eyes.
*Collagen references: Dartmouth Undergraduate Journal of Science, Scientific American, Cosmopolitan
Skin Thickness references: Aging Facts and Theories, Characteristics of the Aging Skin, Skin thickness changes in normal aging skin