Abstract: Objective To investigate the effect of intense pulsed light(420 nm+560 nm)combined with needle free water light in the treatment of refractory acne.Methods From February 2017 to November 2017,90 patients with refractory acne were randomly divided into two groups:control group(n=45)and experimental group(n=45).The patients in the control group were treated with intense pulsed light(420 nm+560 nm),and the patients in the experimental group were treated by needle-free water light based on intense pulsed light.The pigmentation rate of the acne,the number of patients with acne in cheek,forehead and temple after treatment,the treatment efficiency and the number of patients with adverse reactions in the two groups were all compared.Results The pigmentation rate of acne in the experimental group was significantly lower than that in the control group(P<0.05).After treatment,the patients with acne in cheek,forehead and temple of the experimental group were significantly less than that of the control group(P<0.05).The effective rate of the experimental group was significantly higher than that of the control group(P<0.05).The number of adverse reactions in the experimental group was significantly less than that in the control group(P<0.05).Conclusion Intense pulsed light(420 nm+560 nm)combined with needle-free water light is effective and safe in the treatment of refractory acne.It is worthy of clinical promotion.

Key words: Intense pulsed light, Needle free water light, Refractory acne, Pigmentation, Adverse reactions