In vivo preclinical evaluation of thermal safety for monopolar RF devices
Objectives: This study aims to evaluate the thermal safety of the monopolar RF medical device. The study used in vivo porcine skin to analyze thermal damage, inflammatory responses, and changes in skin condition. The goal is to verify the safety of RF-based skin treatment and explore its potential for human application.
Introduction: Radiofrequency technology has emerged as a leading modality for preserving facial elasticity due to its sustained effects and notable improvements in skin firmness and texture. RF therapy delivers high-frequency electrical currents that generate heat within the dermal layers, stimulating collagen remodeling and tissue tightening. This study provides objective, quantifiable data on temperature distribution and tissue responses, contributing valuable reference points for the broader development and evaluation of RF-based medical devices.
Materials / method: This study used a crossbred miniature pig weighing approximately 50 kg as the animal model. The procedure was performed under anesthesia using the monopolar radiofrequency device, with two different energy settings applied. Changes in the skin surface condition were visually assessed using a Folliscope. For histopathological analysis, various staining methods were employed. An infrared thermography camera was used to measure changes in skin surface temperature, the maximum intradermal temperature, and the depth of heat penetration.
Results: The small-area tip setting demonstrated noticeable efficacy, resulting in temporary erythema and mild epidermal damage that resolved entirely within 14 days. Histological analysis affirmed these findings, revealing only mild thermal effects and transient inflammation. The large-area tip exhibited exceptional performance with no visible abnormalities or histopathological issues. Notably, while the small-area tip generated higher surface temperatures, the large-area tip successfully achieved deeper heat penetration and covered a more extensive treatment area without any adverse effects.
Conclusion: This study represents the in vivo preclinical evaluation of the monopolar RF device, offering critical insights into the thermal safety of its treatment protocol. The results validate the high safety profile of the large area tip for skin applications, showing no adverse effects despite deeper thermal penetration. Furthermore, the study provides objective, quantifiable data on temperature distribution and tissue responses, contributing valuable reference points for the broader development and evaluation of RF-based medical devices.
