107 Dermal Wound Healing in an Animal Model Following Thermage Treatment

Abstract

The Thermage system is a radiofrequency (RF) device designed to treat human skin. The Thermage ThermaCool TC™ is a noninvasive, nonablative, nonlaser system that combines cryogen cooling and radiofrequency (RF) energy to volumetrically heat dermal and subdermal tissue. Thermage treatment causes collagen contraction resulting in immediate skin tightening. It has also been clinically shown to tighten skin over time. This long-term tightening effect is believed to result from the body’s wound healing response. We performed studies in a juvenile pig to characterize the wound healing response after ThermaCool treatment in order to elucidate the cellular and molecular events resulting from treatment. Histological markers of the wound healing process were examined over a 1-month period. Collagen gene expression was examined by quantitative PCR. Macrophages and mast cells are important inflammatory cell types that stimulate fibroblast recruitment, collagen synthesis and blood vessel growth. Three to 5 days following treatment, macrophages and mast cells were present in the dermis. By 28 days, both increased dermal blood vessel density and epidermal thickness was observed. Collagen I and collagen III genes were expressed at elevated levels by 21 days posttreatment. ThermaCool™ treatment stimulates dermal remodeling by initiating a wound-healing response. This study demonstrates that thermage treatment results in the recruitment of important cellular mediators of wound healing and increased collagen synthesis in an animal model. These events are presumed to be responsible for dermal remodeling and skin tightening over time in human subjects. Because the Thermage device noninvasively delivers heat energy, it may be a unique tool for the examination of aseptic thermally induced wound models.