Q开关和长脉宽1064nm Nd:YAG激光真皮胶原重建疗效的比较性研究

Comparative study on dermal collagen remodelling using Q-switched and longpulsed 1064-nm Nd:YAG lasers

目的:本研究拟定量地比较Q开关和长脉宽1064 nm掺钕:钇-铝石榴石(neodymium-yttrium-aluminum garnet,Nd:YAG)激光诱导真皮胶原重建的疗效。方法:应用Q开关和长脉宽1064 nm Nd:YAG激光分别对36只雌性昆明小鼠左侧后背皮肤进行连续4次治疗,每次间隔1周,右侧相应的部位作为自身对照。分别于第1次治疗后1h、1天、7天、21天、30天和60天对小鼠皮肤行活组织取材。应用免疫组化方法分别对皮肤组织样品中真皮I、III型胶原进行检测,染色结果应用Motic医学数字图像分析系统进行定量分析。结果:与正常对照组相比,Q开关1064 nm Nd:YAG激光治疗后7天、21天、30天和60天,真皮I型胶原及III型胶原水平明显增高(均P<0.01)。长脉宽1064 nm Nd:YAG激光治疗后21天、30天和60天,真皮I型胶原水平明显增高(均P<0.01);激光治疗后7天、21天、30天和60天,真皮III型胶原水平明显增高(分别为P<0.01、P<0.05、P<0.01、P<0.01)。两组激光的比较:激光治疗后7天、21天和30天,Q开关1064nm Nd:YAG激光治疗组真皮I型胶原水平较长脉宽1064nm Nd:YAG激光治疗组明显增高(均P<0.01),而激光治疗后60天明显降低(P<0.05);激光治疗后7天和21天,Q开关1064nm Nd:YAG激光治疗组较长脉宽1064nm Nd:YAG激光治疗组真皮III型胶原水平明显增高(分别为P<0.05、P<0.01)。结论:Q开关和长脉宽1064nm Nd:YAG激光均可引起真皮胶原重建,但二者的作用效果不尽相同。

Objective The aim of this study was to quantitatively compare the changes of amount of type I and type Ⅲ collagen after nonablative laser treatment using Q-switched and long-pulsed 1064-nm Nd∶YAG lasers.Methods A total of 36 KunMing mice received a series of four nonablative laser treatments separated by 1-week intervals on dorsal skin.The left side of the mouse dorsal skin was exposed by Q-switched and long-pulsed 1064-nm Nd∶YAG laser respectively,leaving the right side as the contralateral controls.Biopsies were performed 1h after irradiation,and 1,7,14,30 and 60 days after the first treatment.Skin samples were studied for type Ⅰ and Ⅲ collagen applying immunohistochemistry.For each section of immunohistochemistry,the staining was quantified using Motic medical digital image analysis system.Results After Q-switched 1064-nm Nd∶YAG laser therapy,a statistically significant increase in type I collagen in the experimental group was seen at days 7,21,30 and 60 compared to the respective control （P＜0.01,respectively）.Type Ⅲ collagen level in the experimental group also showed a marked increase between day 7 and day 60 compared with its control （P＜0.01,respectively）.With long-pulsed 1064-nm Nd∶YAG laser therapy,the amount of type I collagen in the experimental group exhibited a significant increase as compared with the control at days 21,30 and 60 after irradiation （P＜0.01,respectively）.The amount of type Ⅲ collagen in the experimental group was significantly higher than in the control between day 7 and day 60 after treatment （P＜0.01,P＜0.05,P＜0.01,P＜0.01,respectively）.When the two lasers compared,the amount of type I collagen induced by Q-switched 1064-nm Nd∶YAG laser was significantly higher than longpulsed 1064-nm Nd∶YAG laser at days 7,21 and 30 （P＜0.01,respectively）,and lower than longpulsed 1064-nm Nd∶YAG laser at days 60 （P＜0.05）.The amount of type Ⅲ collagen induced by Qswitched 1064-nm Nd∶YAG laser was significantly higher than the long-pulsed 1064-nm Nd∶YAG laser at days 7 and 21 （P＜0.05,P＜0.01,respectively）.Conclusions Both lasers therapy may induce dermal collagen remodeling,although responses are not same betweent different lasers.