兔耳解剖特点与成功建立增生性瘢痕模型的相关性实验研究

Experimental research of correlation between anatomy structure of rabbit ear and creating hypertrophic scar animal model

目的观察兔耳不同部位的解剖结构特点，探讨不同手术方式以及术后处理方法对兔耳增生性瘢痕形成的影响，为成功建立增生性瘢痕动物模型提供理论依据。方法新西兰白兔25只，切取5只兔10只耳60份全层组织标本，进行正常组织学观察；20只兔40只耳，每只兔耳腹侧各建立直径为8mm的全层皮肤缺损6个，总计240个创面。其中10只兔120个创面随机分为4组，手术后7d给予不同处理；另外10只兔120个创面术后不做处理。连续观察创面愈合以及瘢痕增生情况6个月，分别于手术后4、8周留取瘢痕组织行病理学检查和测量瘢痕增生指数。结果正常兔耳不同部位的解剖结构特点不一致；建立兔耳瘢痕模型，部位宜选择在双侧兔耳腹侧内侧缘中、下部位，创伤深度宜破坏软骨膜，瘢痕形成率高，瘢痕增生指数高，持续时间长；术后剥痂可促进创面愈合，不利于瘢痕形成与增生。结论兔耳自身的解剖结构特点与成功建立增生性瘢痕模型有一定的相关性，选择合适的建模部位、合理的创伤深度、术后恰当的处理均可影响瘢痕的形成和增生程度，可以提高增生性瘢痕建模成功率。

Objective To observe the anatomy structure of rabbit ear and the effect of different operation methods and post-operative treatments on the formation of hypertrophic scar. Methods The experimental animals were 25 New Zealand white rabbits. 6 pieces of fuU skin specimens were obtained from each of the ears in 5 rabbits for histological examination. 6 full-thickness skin wounds （d = 8 mm） were made on different sites of ventral side of each ear in the other 20 rabbits. The total number of the wounds was 240. 120 wounds in 10 rabbits were divided into 4 groups randomly to receive different treatments on day 7 postoperatively. No treatment was performed in the other 120 wounds. The wounds healing and the scar formation were observed for six months. The scars were harvested 4 weeks and 8 weeks after operation for pathologic examination and measurement of sear elevation index （SEI）. Results Histological analysis showed that the anatomy structure was different in different sites of the rabbit ear. The best sites for creating hypertrophic scar model were on the medial margin of the middle- and inferior part of ear. The depth of the wound should reach the cartilage membrane of the ear to facilitate the formation of hypertrophic scar. The second strip crust on day 7 postoperatively enhanced the wounds healing and minimized the scar proliferation and hypertrophy. Conclusions There is a close correlation between the anatomy structure of the ear and the creation of hypertrophic scar animal model. The wound site, the depth of wound and the post-operative treatment will affect the formation of hypertrophic scar. The study can help to improve the successful rate of creating hypertrophic scar animal model.