镍钛记忆合金支架治疗兔外耳道狭窄的实验研究

An Experiment of Using Nitinol Alloy Momemorial Stent to Treat the Stenosis of the Rabbi

目的比较镍钛记忆合金支架与硅胶管治疗兔外耳道瘢痕狭窄的疗效。方法将16只外耳道瘢痕狭窄的新西兰大白兔,随机分为植皮组和不植皮组各8只,各组在兔的双侧外耳道分别植入镍钛记忆合金支架和硅胶管,在植入后5、15、30、60天时,植皮组测量两侧的外耳道直径变化;不植皮组分别取双侧外耳道瘢痕组织HE染色观察瘢痕中成纤维细胞变化、RT-PCR检测转化生长因子β1mRNA(TGFβ1)表达,比较两种材料抑制瘢痕增生的效果。结果植皮组使用镍钛记忆合金支架侧各时间点兔外耳道直径明显大于硅胶管侧;不植皮组植入镍钛记忆合金支架侧外耳道瘢痕组织中成纤维细胞数明显少于植入硅胶管侧(P<0.05),TGFβ1mRNA表达亦明显较硅胶管侧降低(P<0.05)。结论镍钛记忆合金支架在治疗兔外耳道狭窄方面疗效显著优于传统的硅胶管。

Objective To compare the effects of nitinol alloy memorial stent with silastic tube in treating the stenosis of the rabbit. Methods 16 rabbits with external ear canal（EEC）stenosis were randomly divided into two groups. One group was implanted with skin on the EEC wound while the other not. By self-comparison method nitinol alloy memorial stent was implanted in a rabbifs one ear and the silastic tube in the other. After days 5, 15, 30, and 60 later, the diameters of the external ear canal （with two materials planted） were measured respectively in the skin--planting group. In the naked group scar tissues were harvested and tested separately according to the planting material. HE coloration were used to study fibroblast hyperplasty while RT--PCR were applied to detecting the TGFβ1mRNA expression. The two brackets were compared according to their effect to scar hyperplasty, Results The EEC diameters using nitinol alloy memorial stent were found more spacious than using silastie tube. HE coloration showed the fibroblast hyperplasia was more mitigatory by using the nitinol alloy memorial stent. RT-PCR also found the TGFβ1mRNA expression was low by using same material. Conclusion The nitinol alloy memorial stent shows obvious superiority over silastic tube in external ear canal stenosis therapy.