The authors have indicated no significant interest with commercial supporters.T here is growing interest in a wide range of nonablative interventions that, predictably, are claimed to rejuvenate skin and subcutaneous tissue ''safely and effectively.'' Although for many years surgery in its many forms has been the criterion standard treatment in aesthetic aspect of aging, nonsurgical methods have always been an attractive choice because of their low invasiveness and shorter recovery time. Nevertheless, most nonsurgical modalities have centered around those that destroy the epidermis and cause a dermal wound, with resultant dermal collagen remodeling and secondary skin tightening and rhytid improvement. Radiofrequency (RF) tissue tightening was developed to create thermal effects in the dermis without external cutaneous wounding. The current review aims at summarizing the nonablative RF currently in use for skin rejuvenation.
HistoryRedundant facial, neck, or body laxity is a major feature of aging and, until recently, surgery was the sole option for its correction. As newer methods developed, RF was introduced at the beginning of the 21st century as a nonlaser technology for cosmetic dermatology, although it has been in use for much longer as a therapeutic option in medicine and surgery. Tissue tightening was one of the first dermatologic uses of RF, where it was used as an alternative or complement to nonablative laser technologies. RF-based systems have been used successfully for nonablative skin rejuvenation, atrophic scar revision, treatment of hypertrophic scars and keloids, 1 treatment of unwanted hair, rosacea, 2 vascular lesions, and inflammatory acne. 3,4
RF Technology
How it Works: Biophysics of Thermal Collagen RemodelingThermal collagen contraction can be applied to the skin for use in aesthetic rejuvenation, restoring skin laxity and aging symptoms. Collagen fibers consist of triple helix strands of protein containing strong hydrogen bonds that deteriorate over the course of several years. The application of thermal energy over a period of time contracts, compresses, and thickens the collagen fibers. An ideal heat of 571C to 611C is adjusted for collagen shrinkage, with a time depending on type and area of skin applied. The dermal collagen fibers are detected at a depth of 1 to 2 mm for treatment of skin laxity.
Nonablative Skin RemodelingPhotomodulation, a nonablative laser treatment, allows matrix metalloproteinase reduction to produce an increase in the cellular response of dermal collagen. There are two hypotheses to explain this treatment method: (1) water and collagen absorb the light energy, producing a thermal effect on the dermis, and (2) cellular mediators and growth factors
