Efficacy and Safety of a Novel Monopolar Radiofrequency Device for Mid and Lower Face Rejuvenation: A Retrospective Pre-Post Comparative Study

Aging of the face progresses through complex structural changes, including a decrease in skin elasticity, collagen loss, changes in subcutaneous fat distribution, and relaxation of the superficial musculoaponeurotic system (SMAS). These changes are particularly prominent in the mid and lower face, which has led to the widespread use of non-invasive energy-based lifting and contouring procedures in cosmetic and dermatology clinical practices.

Traditional laser and high-output radiofrequency (RF) based lifting treatments generally deliver brief high-temperature energy (over 70°C) to tissues, inducing protein denaturation and coagulation, followed by collagen remodeling through the wound healing process to achieve long-term effects. Although these treatments can induce relatively rapid clinical changes, side effects such as pain during the procedure, as well as erythema, edema, and blisters, which are associated with thermal damage, have been reported.

To address these limitations, there has been increasing interest in low-temperature-maintaining RF treatments that minimize tissue degeneration while inducing biological responses. In particular, RF stimulation in the range of 43-45°C is known to be a temperature range that does not induce tissue coagulation and is believed to trigger reactions related to cellular metabolic activation and programmed cell death (apoptosis), rather than necrosis-based damage with accompanying acute inflammatory responses. This approach has advantages, including relatively less pain, shorter recovery times, and the possibility of repeated treatments.

Recent studies have also reported that TRPV1 receptors, activated by thermal stimulation above 43°C, may be associated not only with pain transmission but also with the activation of fibroblasts, regulation of collagen and extracellular matrix (ECM) synthesis, and regulation of adipocyte metabolism. Some experimental studies have observed an increase in fibroblast proliferation and ECM production when RF energy was applied to maintain a temperature range of 43-45°C for a certain period. However, this evidence has been largely limited to studies focusing on the skin layer, and there is still limited systematic human research on the clinical efficacy and safety of RF treatments that simultaneously stimulate both the skin and subcutaneous fat layers.

NeoSculpt is a monopolar RF system designed with a multi-channel handpiece structure using different frequencies (1 MHz and 2 MHz) to deliver energy progressively to the dermal-SMAS interface and subcutaneous fat layers. Through a low-temperature-maintaining RF protocol, it is expected to achieve mid- and lower-face lifting and contouring effects. However, objective data regarding the efficacy, safety, and clinical changes associated with the use of this device in actual clinical settings are not yet sufficiently accumulated.