壳聚糖管状支架联合肌瓣修补颈段食管部分缺损

Chitosan tubular stent combined with muscle flaps for repair of partial defects of the cervical esophagus

背景:多年来使用肌肉、皮肤、骨骼肌瓣及胃、肠等管腔组织等作为人工食管修补食管缺损,但效果都不甚理想。目的:探讨壳聚糖管状支架联合肌瓣修补颈段食管部分缺损的可行性。方法:取30只大耳白兔,制作颈段食管部分缺损动物模型,实验组20只破损处植入壳聚糖管状支架,外覆自体颈部肌瓣修补;对照组10只直接覆盖自体颈部肌瓣修补。于植入后第2,4,8周观察支架吸收及破损处组织学变化;植入后第10周行食管钡透,观察有无狭窄发生及食管蠕动。结果与结论:植入后2周,实验组及对照组均见肌肉组织结构,细胞肿大,炎性细胞浸润,表现为急性炎症反应。植入后4周,实验组替代物肌瓣组织结构清晰,炎性反应减弱,无明显纤维组织增生;对照组缺损处肌组织结构可见,肌肉组织表面可见纤维组织细胞生长,伴有少许炎性细胞。植入后8周,实验组肌肉组织瓣表面大部分鳞状上皮化,可见食管黏膜组织,黏膜下伴有慢性炎性反应,较4周时明显减轻;对照组为慢性炎症反应,伴有明显纤维组织增生,表面无鳞状上皮化生及黏膜再生。钡餐透视显示实验组食管通畅无狭窄,蠕动减弱;对照组食管部分狭窄,无蠕动。表明壳聚糖管状支架联合肌瓣可较好修补颈段食管部分缺损。

BACKGROUND： Over the years, muscle, skin, skeletal muscle flaps and luminal tissues, such as stomach and intestines, are used as an artificial esophagus to repair esophagus defects, but the results are not good. OBJECTIVE： To investigate the feasibility of chitosan tube stent combined with muscle flaps to repair partial defects of the cervical esophagus. METHODS： Thirty white rabbits were used to make animal models of partial cervical esophageal defects, and randomly divided into experimental group （n=20） and control group （n=l 0）. Esophagus defect in rabbits of experimental group was repaired using autologous muscle flap with a chitosan tube stent, and esophagus defect in the control group was repaired only with muscle flap. Gross and histological appearance was observed at weeks 2, 4 and 8 after operation, and barium sulphate X-ray screen was performed at week 10 after operation. RESULTS AND CONCLUSION： After 2 weeks, muscle tissue structure, cell swelling, and inflammatory cell infiltration could be seen in the experiment and control groups, exhibiting an acute inflammatory reaction. After 4 weeks, the experimental group showed clear muscle flaps, reduced inflammatory reaction, and no obvious fibrosis; while in the control group, muscle tissue could be seen at defect site, with growth of fibrous tissue cells and a few of inflammatory cells. After 8 weeks, in the experimental group, squamous metaplasia could be seen on the gross surface of the muscle flaps, esophageal mucosa could be seen, accompanied by chronic inflammatoryreaction under the mucosas that had a clear abate than that at 4 weeks after implantation; in the control group, chronic inflammatory reaction could be found, accompanied by clear fibrosis but no squamous metaplasia and mucosal regeneration. Barium sulphate examination found that the esophagus was smooth with a slight motility in the experimental group, but there was a part of stricture in the esophagus without motility. These findings suggest that the chitosan tube stent combined with muscle flaps could better repair partial defects of the cervical esophagus.