The fact is the properly applied STIMULATIVE radiofrequency / ultrasound cavitation can both lead to adipocyte apoptosis, i.e. programmed cell death of fat cells. This is fat cell death that gradually happens over days and weeks with a course of SAFE treatments provided under the pain threshold (less than 41-43ºC on the skin surface or 43-47ºC in the deeper skin layers). This ensures safety of all other tissues, except fat cells, and in fact also stimulates fibroblast (collagen cell) function, which leads to skin tightening, especially with RF.