Ultherapy uses focused ultrasound energy to target the deeper 4.5 mm SMAS...
https://helen-mitchell11.raindrop.page/bookmarks-74099039
Ultherapy uses focused ultrasound energy to target the deeper 4.5 mm SMAS layer, stimulating collagen over 3 to 6 months for gradual lifting. Compared to RF, which heats skin to 40-45°C mainly in the superficial layers, Ultherapy reaches deeper tissue