RESUMO
Objective To investigate the structural and ultrastructural changes of the skin induced by micro-plasma radio-frequency technology,and to preliminarily discuss this novel technology mechanism.Methods Thirty guinea pigs were enrolled and randomly divided into three groups.They were radiated by different dose parameters 40 W,10 kJ; 60 W,10 kJ and 80 W,10 kJ.Every guinea pig's back was divided into two parts which was removed after immediately,one week and one month,and dermatopathology and transmission electron microscopy (TEM) were performed.Results The different dose setting could make different skin change of immediately effect.When dose setting was 40 W,10 kJ,skin showed that epidermal cells were integrity and the superficial layer of dermis collagen tissue was light homogenization.When dose setting was 60 W,10 kJ,epidermal tissue showed focal emergence of fractional shape change and obvious homogenization.When dose setting was 80 W,10 kJ,epidermal showed complete vaporization loss or degeneration necrosis,and dermal superficial and middle layer of collagen tissue showed a large area of homogenization.Skin superficial collagen tissue's structure gradually showed dense and 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 originally normal structure and cell structure disappeared and obviously showed massive apoptosis.A small amount of apoptosis was showed but collagen structure gradually restored after one month.Conclusions The novel micro-plasma radio-frequency has obvious dose effect to skin,and its main target tissues are dermal collagen tissue.It can stimulate skin collagen hyperplasia in certain degree.