Two-Treatment Protocol for Skin Laxity Using 90-Watt Dynamic Monopolar Radiofrequency Device With Real-Time Impedance Intelligence Monitoring

September 2014 | Volume 13 | Issue 9 | Original Article | 1112 | Copyright © September 2014


David McDaniel MD,a Robert Weiss MD,b Margaret Weiss MD,b Chris Mazur BS,a and Charmaine Griffin CCRPa

aMcDaniel Institute of Anti-Aging Research,Virginia Beach, VA
bMaryland Laser Skin & Vein Institute, Hunt Valley, MD

Abstract
Multiple devices are currently on the market that employ radiofrequency to non-invasively treat skin laxity and wrinkle reduction. The study device was a unique monopolar radiofrequency device FDA cleared for the treatment of wrinkles and rhytids. The delivery system allows constant monitoring of the real-time local skin impedance changes, which allows radiofrequency energy to be more uniformly dosed over an entire treatment area.
OBJECTIVE: The objective was to validate effectiveness of a modified treatment protocol for a unique monopolar radiofrequency device, which has been engineered with greater power and self-monitoring circuitry.
METHODS: Twenty-four female subjects received bilateral monopolar radiofrequency treatments to the mid and lower face from the sub malar region to the submentum. Subjects completed 1 and 3 month follow ups with digital imaging. Skin biopsies (on 4 subjects) and ultrasound measurements (on 12 subjects) were completed.
RESULTS: Assessments demonstrated a reduction in skin laxity of 35%, a reduction in fine lines/wrinkles of 42%, and a reduction in the appearance of global photodamage of 33%. Expert photograding demonstrated 92% of subjects showing at least a mild improvement in skin laxity at three months post treatment. 50MHz ultrasound measurements in 12 subjects showed an increase of 19% in skin density. Histology showed a marked increase in dermal collagen and elastin fibers in two subjects who demonstrated a clinically noticeable reduction in skin laxity and minimal changes in two subjects who demonstrated minimal clinical improvements. There were no significant adverse events reported.
CONCLUSION: This modified radiofrequency device and treatment protocol was well tolerated and produced improvements in the appearance of skin laxity and overall anti-aging effects in the majority of subjects. Objective measurements including ultrasound and histology help explain the clinical outcome.

J Drugs Dermatol. 2014;13(9):1112-1117.

INTRODUCTION

The appearance of the face and neck is profoundly affected in the aging process. There is decreased tissue elasticity coupled with rearrangement of facial volume that is compounded by the effects of gravity.1 As the appearance of the face and neck is a primary concern of many people, ways in which to tighten the skin are increasingly in demand. One such method to address this concern is radiofrequency treatment, which produces an electrical current that uses the resistance within the various skin layers to convert the delivered energy into thermal energy.2 Radiofrequency creates oscillating electrical current, causing vibration and collisions between charged molecules, thus resulting in the production of heat as described by Belenky, et al.3 This radiofrequency heating occurs regardless of skin chromophores or skin type and is not dependent upon selective photothermolysis but rather heating of water. Thus, hydration of tissues in the radiofrequency treatment area is important. There are many different types of radiofrequency devices using multiple types of radiofrequency energy, temperature ranges, and target depths.4,5 Radiofrequency heat has different biological and clinical effects, depending upon the method of delivery and depth of heating. In the dermis, which is comprised of collagen, elastin, and ground substances, radiofrequency mediated thermal stimulation of this matrix results in an immediate and temporary change in the helical structure of the collagen.6 It is also believed that radiofrequency thermal stimulation results in a micro-inflammatory stimulation of fibroblasts, which produces new collagen (neocollagenesis) and new elastin (neoelastogenesis), as well as other proteins to enhance dermal structure.7,8
To allow a constant and consistent radiofrequency energy delivery, there is a need for the power to be maximized and normalized for skin impedance. Some first generation radiofrequency skin tightening devices offer skin impedance measurements, but these measurements are not real-time measurements of the target area. Some radiofrequency devices use impedance of one sampled area to “average” impedance at the beginning of treatment. This initial one-time impedance measurement is used for the duration of the treatment and does not allow for changing