大鼠食管支架置入术后再狭窄模型构建及观察

The establishment of esophageal re-stenosis model by using esophageal stent implantation:observation in experimental rats

目的探讨大鼠食管支架置入及术后食管良性增生性狭窄模型构建的可行性和安全性。方法实验使用定制的自膨式金属直筒支架(直径5 mm,长15 mm),其中部两侧各有一外突倒刺用作固定,防止滑脱移位。12只健康Sprague-Dawley大鼠随机分成A组(空白对照组)和B组(支架置入组),每组6只;B组大鼠食管内置入支架,分别于置入即刻、1周、4周作食管造影。4周后处死所有大鼠,取A组正常食管组织及B组支架部位食管组织作大体形态、光镜等病理学分析。结果 B组食管内支架置入均获成功,术后即刻、1周、4周复查造影均未发现食管内支架移位,手术及随访期间无严重并发症发生。与A组相比,4周后B组复查造影显示支架段食管增生导致食管狭窄,取出支架部位食管段肉眼见管腔明显狭窄,光镜下呈典型良性增生样表现。结论采用大鼠构建食管支架置入后再狭窄模型安全、可行,带倒刺食管支架能够明显降低支架置入后移位发生率。

Objective To evaluate the feasibility and safety of establishing benign proliferative esophageal stenosis model by using stent implantation in experimental rats. Methods A customized self- expanding, metallic and straight tubular stent was used in this experiment （5 mm in diameter and 15 mm in length）, on both sides at the stent＇s middle part there was a protruding barb that was used as a fixation device. Twelve healthy Sprague Dawley （SD） rats were randomized divided into group A （blank control group） and group B （stent implantation group）, with 6 rats in each group. Esophageal stent implantation was employed in the rats of group B, and esophageal radiography was separately performed immediately, one and 4 weeks after stent implantation. All the experimental rats were sacrificed 4 weeks after stent implantation. The normal esophageal tissue of the rats in group A and the esophageal tissue at stent site of the rats in group B were collected and sent for pathological examinations, including gross morphology, light microscopy, etc. Results Successful stent implantation was achieved in all rats of group B, and the esophageal radiography performed immediately, one and 4 weeks after stent implantation showed no esophageal stent displacement; no severe complications occurred during the operation or follow-up period. Compared with group A, esophageal radiography reexamination performed 4 weeks after stent implantation in group B revealed that esophageal stricture at stent segment, caused by benign tissue hyperplasia, could be observed. The esophageal stent segment was taken out, its lumen was obviously narrowed under gross observation, and typical benign hyperplasia could be seen under optical microscope examination. Conclusion Using esophageal stent implantation to establish esophageal stenosis model is safe and feasible in experimental rats. The use of esophageal stent with barbs can significantly reduce the incidence of stent displacement. （J Intervent Radiol, 2017, 26： 157-160）