Histological Research Of Trachea Reconstruction By Autogenous Jejunal Graft

Objective: Establish a canine model of the tracheal reconstruction of partial free jejunal autotransplantation to investigate the histological changes of jejunum fixed with metal stent and wrapped with omentum in abdominal cavity after vascularization.Methods: The animal models of 6 dogs with free jejunum composite metal stent wrapped around the omentum were established by three-stage operation.1.After freeing part of the jejunal tube,the common metal external stent was used,and the polymer polypropylene pipe was used as the inner stent,and the whole jejunal tissue was wrapped by the omentum to achieve vascularization.2.Ligated the main branches of mesenteric arteriovenous arteries and veins at the fourth week.3.Took the tissue out,several items were observed,blood supply,bacterial state of intestinal secretion and pathological changes of intestinal wall were evaluated at the eighth week.Results:One of the 6 dogs died of overanesthesia immediately after supplementary anesthesia,and the rest 5 experimental dogs survived 8 weeks after operations.the diet,defecation and urination were good,without fever and weight lossing.It can be seen that the transplanted jejunum tissue is ruddy in color and has been completely wrapped by the greater omentum.the shape of the wire can be vaguely recognized at the fourth week,.a small number of small blood vessels can be seen converging into the greater omentum,and the vascular pedicle has no torsion.The end-to-end anastomosis of jejunum was continuous and no stenosis was found.Abdominal adhesion was more serious than before at the eighth week,the omentum completely wrapped instead of the jejunal tissue,the volume was thicker than before,accompanied by 7-10 thicker neovascularization into the omentum..After the jejunal segment wrapped by greater omentum was freed,the length of greater omentum vessels was more than 30 cm,which could be transplanted from abdomen to neck.A small amount of sticky yellow secretion spilled out of the omentum tissue,and no obvious colony growth was found after the bacterial culture of the intestinal fluid was collected.the omentum,metal stent and intestinal wall were completely integrated,and the intestinal cavity did not collapse.The pathological observation of the transverse section of the intestinal wall showed that the fat vacuoles in the omentum of the transplanted jejunum were arranged neatly and the number of new capillaries was large,showing chronic tissue reactive inflammatory changes.The omentum has been basically fused with the serous layer of the intestinal wall,and only a small number of residual cavities can be seen.There was no significant change in myometrium.The mucosal layer showed capillary occlusion,reduced blood supply to the mucous layer,chronic inflammatory tissue infiltration in the mucous layer and submucosa,smooth and no edema,and most of the glandular cells degenerated into vacuoles and were still covered with monolayer columnar epithelium.Part of the structure of the villi was destroyed and the arrangement was not neatly arranged.Conclusions:Part of the free autologous jejunum wrapped around the vascularized omentum and supported by metal stents accords with the conditions for autogenous transplantation and tracheal reconstruction.