Of the dermatologic indications for radiofrequency microneedling (RFMN), the published evidence is strongest for skin rejuvenation, acne vulgaris, acne scars, and axillary hyperhidrosis, according to results from a new systematic review.
"Most devices for aesthetic purposes induce denaturation and remodeling of collagen, elastin, and other dermal structures through tissue injury and stimulating the body's wound-healing response," lead study author Marcus G. Tan, MD, told this news organization during the annual conference of the American Society for Laser Medicine and Surgery. "Radiofrequency microneedling is no exception in this regard. RFMN creates perforations in the skin and delivers radiofrequency-generated thermal energy into the underlying tissue. However, RFMN is unique in that thermal energy is delivered in a fashion that produces a reverse temperature gradient to most ablative lasers."
When using ablative lasers, which target water as its chromophore through selective photothermolysis, the temperature gradient is highest at the epidermis and papillary dermis, and decreases as it penetrates the deeper structures of the skin. In RFMN, radiofrequency energy is delivered directly to the target depth through the microneedle electrodes, thus creating a temperature gradient that is highest in the deep, target structures and cooler at the superficial structures. "This results in less unwanted epidermal heating and reduces the risk of postinflammatory hyperpigmentation," explained Tan, a resident in the division of dermatology at the University of Ottawa.
