肺组织瓣包埋金属支架重建气管、食管的动物实验研究

Experimental use of pulmonary flap with alloy stent for the reconstruction of trachea and esophagus

目的 用犬的自体肺组织瓣包埋金属支架重建气管、食管,探索应用肺组织瓣重建气管、食管的可行性.方法 24只杂种犬,分别制成气管、食管缺损模型,用自体肺组织瓣内衬金属支架分别修补.定期处死实验犬,行大体观察、组织学观察和影像学检查.结果 18只实验犬存活超过2周以上.肺组织瓣与气管、食管紧密结合,未发生缺血坏死,术后12周被走行一致的胶原纤维替代.肺组织瓣表面有新生上皮爬行,且爬行较快.结论 自体肺组织瓣与气管、食管上皮细胞有较好的相容性,能为气管、食管上皮的爬行提供良好的载体.

Objective To study the feasibility of applying autogenous pulmonary tissue flap with alloy stent to correct the defects of trachea and esophagus. Methods Twenty-four dogs were divided into tracheal and esophageal groups. Bronchus was ligated to prepare a pulmonary flap. And a defect of 3 -4 cm long and 1/2-2/3 perimeter was made in tracheal or esophageal wall. Pulmonary arteries and veins were protected. Then the pulmonary gas was emitted to create a pulmonary tissue flap. The defect was repaired with a pulmonary flap with a self-expanded stent inside. The gross appearance, histological appearance, CT and barium X-ray films were observed at Weeks 2, 4, 6 and 8 post-operation. Results Eighteen experimental dogs survived over 2 weeks. Anatomotic leak was the main cause of death. Two dogs died of perforation of ulcer in esophageal group. Reliable cicatrisation was observed between the pulmonary tissue flap and damage area. A quick growth of new tracheal and esophageal epithelium was observed from periphery area to central area. During the first 2 weeks, a little epithelization was observed at free edge of anastomosis equivalent to 1 - 2 layers of new epithelial cells. At weeks 4-6 post-operation, the internal surface of defect was covered with 3 - 5 layers of epithelial cells. At Weeks 8-10 post-operation, the luminal surface was covered with 6 - 8 layers of stratified epithelial cells. More ulcers could be observed on the surface of pulmonary tissue flap in esophageal group. In pulmonary flap, massive fibrous tissue proliferated and fibroblasts were active, but no necrosis occurred. CT and barium X-ray showed no obstruction in anastomotic stoma. Conclusion With an excellent compatibility with epithelial cells of trachea and esophagus, the autogenous pulmonary tissue flap can support the mucosal crawl in the defect of trachea and esophagus. When combined with alloy stent, it may be a choice procedure for reconstructing the defect of trachea and esophagus.