Ultherapy uses focused ultrasound to reach the 4.5 mm SMAS layer, which...

https://speedy-wiki.win/index.php/What_Does_a_%27Proper_Assessment%27_Look_Like_Before_Skin_Tightening%3F

Ultherapy uses focused ultrasound to reach the 4.5 mm SMAS layer, which standard HIFU often can’t target as deeply. RF heats skin to 40-45°C for collagen boost but doesn’t reach the same depth