Assessment Of Chemical Peel Efficacy And Skin Barrier Function In The Treatment Of Mild To Moderate Acne Using Non-invasive Skin Testing Techniques

Objective:Non-invasive skin testing techniques were employed to observe the effect of chemical peel treatment on the skin barrier from the perspectives of micromorphology,physicochemical properties,and visual analogue,and to assess the efficacy and the action characteristics of common chemical peeling agents on mild to moderate acne.Methods:Thirty consecutive cases each with mild to moderate acne who came to the Department of Dermatology of the First Affiliated Hospital of Kunming Medical University from September 1,2020 to December 15,2020 were selected.After obtaining informed consent,patients were randomly and equally divided into three groups and respectively treated with glycollic acid(GA),salicylic acid(SA),and salicylic-glycolic combination acid(CA)for three times at an interval of 4 weeks.To assess the overall acne condition and epidermal barrier function,four aspects of skin condition and function,including the improvement of various types of acne lesions and skin physiological functions,visual analogue scale system(VISIA),and microstructure(reflectance confocal microscopy,RCM),were assessed and analyzed before,immediately after,24 hours after treatment,and 7 days after each treatment.Results:1.Overall acne condition:There was no significant difference in the overall treatment effect of the three acids on mild to moderate acne(P>0.05).All mild to moderate acne improved after treatment,and showed an overall trend of gradually increase in the rate of acne improvement as the number of treatments increased,with mild acne consistently improving at a higher rate than moderate acne.2.Skin physiological function test:the epidermal water content,skin lipid content and pH decreased in all three groups immediately after treatment,while trans-epidermal water loss increased(P<0.05).The epidermal water content in the GA group was slightly higher than the other two groups,but with time,the epidermal barrier function gradually repaired,and the epidermal physicochemical test values almost recovered to baseline levels in approximately 1 week(P>0.05).3.VISIA:Patients in all three groups could had an increased pigmentation differences visible on the skin surface,mild epidermal edema,temporary capillary dilation,and increased porphyrins immediately after each treatment,as evidenced by significant changes in some indicators of spots,texture,pores,red areas,and purple matter(P<0.05).These changes recovered to almost the baseline values 7 days after treatment.There was no significant difference in index changes between the three treatment groups(P>0.05).4.RCM:In all three groups,the stratum corneum thickness and epidermis thickness were significantly thinner immediately after each treatment compared with those before the treatment(P<0.05),whereas the stratum corneum thickness and epidermis thickness were still thinner 24 hours and 7 days after treatment(P<0.05).The rate of change in stratum corneum and epidermis thickness was the most significant in the GA group immediately after treatment(P<0.05).Hair follicles with thinner post-treatment capsule wall thickness,reduced contents,and reduced internal diameter were seen in all three groups on day 7 after each treatment compared to those before treatment.Follicle scores within each group increased with increasing number of treatment days(P<0.05),but no significant difference in follicle scores was observed among groups(P>0.05).Conclusion:1.The results of barrier assessment by three testing methods,namely skin physiological function test,VISIA and RCM,showed similar trend,with the most significant changes in the data of each test of skin barrier immediately after treatment and almost recovered within 7 days without irreversible damage.2.0-7 days after chemical peel treatment is a critical period for skin barrier repair.Strengthening hydration and sun protection could be beneficial to reduce the occurrence of side effects and improve the healing effects.3.The skin microstructure changes were consistent with the clinical condition improvement,which could reflect the degree of acne improvement,indicating that RCM has some value in assessing the efficacy of acne.4.There was no significant difference in the overall efficacy of the different chemical peeling agents on acne,and the efficacy was better for mild acne than for moderate acne.All three acids had therapeutic effects on all types of acne lesions,and the characteristics of action were consistent with the mechanism of action.