Experimental study of the effects of fractional laser and pulsed dye laser combined with multi-point triamcinolone injection on hypertrophic scar in rabbit ears
10.3760/cma.j.cn114453-20200609-00346
- VernacularTitle:点阵激光联合脉冲染料激光加多点微量注射曲安奈德对兔耳增生性瘢痕的影响
- Author:
Ying LEI
1
;
Shiqi PENG
;
Hongyang CHEN
;
Huawei OUYANG
;
Jun TAN
Author Information
1. 湖南省人民医院整形和激光美容外科，长沙 410005
- Keywords:
Cicatrix;
Lasers, dye;
Ultra-pulsed fractional laser;
Triamcinolone
- From:
Chinese Journal of Plastic Surgery
2020;36(10):1128-1138
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the therapeutic mechanism of fractional laser combined with pulsed dye laser and multi-point microinjection of triamcinolone in the treatment of hypertrophic scars in rabbit ears.Methods:In this study, 80 hypertrophic scar models of rabbit ears were made and randomly divided into 4 groups: control group, laser combined group, laser combined multi-point microinjection group, simple traditional injection group, 20 scar models in each group.The control group was not given treatment; the laser combined group was treated with pulsed dye laser first, followed by fractional laser at the same time; the laser combined with multi-point microinjection group was treated with pulsed dye laser and fractional laser first, followed by multi-point microinjection of triamcinolone in the scar immediately after laser treatment; the traditional injection group was injected with triamcinolone in the scar.The gross appearance of hypertrophic scars was observed and recorded in 4 groups. At 7 days and 2 months after treatment, the hypertrophic scars were cut and the histological study were performed by HE staining; the expression of collagen was observed by Masson staining and the volume fraction of collagen was measured; the number of micro-vessels was observed by CD31 staining and the micro-vessel density was measured.One way ANOVA was used to show the difference between groups, LSD posthoc test was used to compare between groups, and Pearson correlation coefficient was used to analyze collagen volume fraction and micro-vessel density.Results:Two months after the treatment, the histological results showed that the scar thickness of the laser combined group and the laser combined with multi-point microinjection group was significantly thinner than that of the control group, the texture of the scar was softened, the red color gradually became lighter, and approached to the color of the surrounding skin. Compared with the control group, the scar in the traditional injection group was thinner, softer and lighter. The scar thickness of laser combined with multi-point microinjection group was thinner than that of laser combined group and simple traditional injection group.Masson staining was used to calculate the collagen volume fraction (CVF): the expression of CVF in hypertrophic scar tissue of each group was reduced. The CVF values of each group at the 7th day and the 2nd month were compared. There was statistically significant difference between the laser combined group, the laser combined multi-point microinjection group and the simple traditional injection group ( P<0.05), but there was no statistical difference between the control group ( P>0.05). The CVF value of each group was further compared at 2 months after treatment, the laser combined multi-point microinjection group 0.05). 2 months after treatment, the MVD values of each group were compared with the result as the laser combined with multi-point microinjection group < laser combined group < simple traditional injection group, but there was no statistical difference between the laser combined with multi-point microinjection group and the laser combined group ( P>0.05). There was statistical difference between the laser combined with multi-point microinjection group and the laser combined group and the simple traditional injection group ( P< 0.05). The Pearson correlation coefficient was r=0.972, which indicated that there was a positive correlation between the collagen content and the number of micro-vessels. Conclusions:The use of fractional laser combined with pulsed dye laser and multi-point microinjection of triamcinolone in the treatment of hypertrophic scars in rabbit ears can evenly reduce the number of fibroblasts, promote the normalization of collagen density and arrangement, and reduce collagen volume fraction and micro-vessel density. The curative effect is better than fractional laser combined with pulse dye laser therapy and simple traditional triamcinolone injection therapy. There is a positive correlation between collagen content and micro-vessel density in hypertrophic scars. Simultaneously inhibiting the proliferating blood vessels can improve the therapeutic effectiveness.
