Histological and Electron Microscopic Analysis of Fractional Micro-Plasma Radio-Frequency Technology Effects

November 2013 | Volume 12 | Issue 11 | Original Article | 1210 | Copyright © November 2013

Fan Xin MD PhD,a Liu Li-hong MD,a Macrene Alexiades-Armenakas MD PhD,b
Stefanie Luebberding PhD,b Shi Cui-ping MD,a Han Yue MD,a An Yu-xi MD,aYue Dan-xia MD,a
and Yang Rong-ya MD PhDa

aDepartment of Dermatology, General Hospital of Beijing Region of PLA, Beijing, China
bAssistant Clinical Professor, Yale University School of Medicine and Director and Founder,
Dermatology and Laser Surgery Center, New York, NY

Abstract
OBJECTIVE: The aim of this explorative study was to investigate the histological effects of a novel micro-plasma radio-frequency technology for skin rejuvenation the assessment of different parameters.
METHODS: Thirty guinea pigs were randomly selected and were distributed into three treatment groups: 40W/10KJ, 60W/10KJ, and 80W/10KJ. The treated skin was analyzed immediately, one week and one month post-treatment using histology and transmission electron microscope (TEM).
RESULTS: At 40W/10KJ, the epidermis was intact and light collagen homogenization was observed in the papillary dermis. At 60W/10KJ, the epidermis showed focal emergence of fractional shape change and obvious papillary dermal homogenization. At 80W/10KJ, the epidermis was completely vaporized and the superficial and mid-dermal layers of collagen tissue showed a large area of homogenization. Dermal collagen increased in density and became arranged in an orderly manner after one week and markedly thickened and arranged in compact manner after one month. TEM showed that epidermal cells were relatively complete, intercellular structure was normal, but the dermal collagen lost its typical structure, cell structure disappeared and showed massive apoptosis. A low level of apoptosis marker expression was observed, with collagen structure restoration after one month.
CONCLUSION: The treatment with the novel micro-plasma radio-frequency technique has a dose-dependent effect on the skin, especially on the dermal collagen tissue, where neocollagenesis is stimulated.

J Drugs Dermatol. 2013;12(11):1210-1214.

Introduction

Recently, fractional ablative radiofrequency (RF) technology has become commercially available and is gaining clinical recognition and popularity as novel fractional lasers in procedural dermatology.1,2 When compared to fractional ablative lasers (Er:YAG and CO2), fractional ablative radiofrequency technology to be bipolar or unipolar is still lacking understanding skin interaction and morpho-histology evidence.3,4
In the fractional bipolar RF devices the technology is forming an array of positive and negative charged multielectrod-pins on the surface of the skin. The RF current flows via the skin between the electrode-pins rows. This results in heating the pins to temperature leading to ablation, coagulation/necrosis and sub necrotic tissue zones, while leaving intact or slightly affected zones in between the pins.
In contrast, the Accent XL (Alma Lasers Ltd., Caesarea, Israel) is a novel unipolar RF-based technology, creating fractional ablative micro-plasma perforation on the skin.
Plasma is a partially ionized gas that contains charged carriers (electrons and ions), active radicals and excited molecules.
When a plasma contacts tissue, various effects can be achieved, from vaporization to simple heating of biological tissue. When the plasma interacts with the skin, there is a superficial, microplasma injury (ablative-thermal) of the skin ranging between 150-200 μm in depth and 80-120 μm in width.5
The purpose of this study was to document dose-response skin interaction of a novel unipolar RF micro-plasma technology in animal model through evaluation histology and ultra microstructure trends over time. In addition, the study aimed to suggest new revelation of the technology current clinical application.

Materials & METHODS

Thirty male and female cavies were randomly selected for this study. Cavies weight ranged between 0.25-0.35kg and age between 7-10 years old (Li Tong Li Hua, Beijing animal company, China). Each cavy was fed by group separately to adapt the environment. Animal waiting time for experiments was one week.
The Accent XL (Alma Lasers Ltd.) is a radiofrequency platform operated at a frequency of 40.68 MhZ. The Accent XL RF-based handpiece creates ablative fractional micro-plasma events,