Tissue reaction and injury after nitinol artificial esophagus replacement / 中国组织工程研究

ABSTRACT

BACKGROUND:Previous experiment has confirmed that the nitinol artificial esophagus is an artificial succedaneum which can be used for replacing an esophagus resected and rebuilding esophageal tube. OBJECTIVE:To observe the tissue reaction of the neo-esophagus and the adjacent organs injury contacted with the nitinol artificial esophagus after replacement. METHODS:Eight miniature pigs were selected and modeled by resection of a 70 mm segment of the thoracic esophagus. After modeling, the nitinol artificial esophagus was inserted into the proximal and distal end of the thoracic esophagus at an insert distance of about 10 mm. After that, the nitinol artificial esophagus with polyester connecting ring was sewed into the thoracic esophagus in a manner of ful-thickness anastomosis. After operation, the pigs were subjected to feeding regulation measures to control the shedding time of the artificial esophagus. Two model pigs were sacrificed for anatomical observation at 1, 2, 3, 4 months postoperatively, respectively. The tissue reaction during the neo-esophagus formed procedure and adjacent organs injury contacted with the nitinol artificial esophagus were observed. RESULTS AND CONCLUSION:Al pigs survived without complications such as thoracic hemorrhage, pneumothorax, pyothorax, esophageal perforation and anastomotic leakage. The experimental animals with the nitinol artificial esophagus fixed in situ had no dysphagia for eating semisolids food (Bown’SⅡ). Autopsy findings showed that there was slight membrane-like adhesion between partial pleura and lung. No hydrothorax was found. The nitinol artificial esophagus was wrapped up by the neo-esophagus. There was slight membrane-like adhesion between the neo-esophagus and the adjacent organs such as the lung, aorta and esophageal mucosa. The esophageal mucosa covered the neo-esophageal entocoele from esophageal stumps to intermedius of neo-esophagus until completely covered. Histological findings of the neo-esophagus showed that in imbed cycle of the nitinol artificial esophagus the tissue reaction showed aseprtic inflammation reaction and foreign body reaction around the implant. These tissue reactions were most severe at 1 month after operation and thereafter relieved gradual y.