[MORPHOLOGY AND PATHOLOGICAL CHANGES OF POLYTETRAFLUOROETHYLENE ARTIFICIAL TRACHEAL TRANSPLANTATION]

To observe the morphological and pathological changes after transplantation of polytetrafluoroethylene (PTFE) in vivo.

PTFE microporous polypropylene tube which was encircled by spiral steel wire was used to prepare the artificial trachea. Forty New Zealand white rabbits (weighing, 4-5 kg) were selected, and were divided into 2 groups. After the cervical trachea (2 cm in length) was removed, the end-to-end anastomosis between the trachea and PTFE artificial trachea was performed in the experimental group (n=20), and end-to-end anastomosis of the trachea in the control group (n=20). The survival of the rabbits was observed after operation; the X-ray, gross, and histological observations were carried out at 2, 4, and 6 months after operation. The longitudinal tensile and radial support biomechanical tests were performed before and after transplantation.

The survival time was more than 2 months and the artificial airway was patency in 15 rabbits of the experimental group; the tissue outside the artificial trachea was like tracheal tissue, which filled in the defect, but it was more than 4 months. X-ray observation showed that the PTFE artificial trachea had no obvious displacement in the experimental group, and no tracheostenosis was observed in the control group. After 2 months, there was no epithelial tissue on the artificial airway wall; after 4 months, there was some epithelial cells on the artificial airway wall, incomplete endothelialization and trachea layer structure were seen with no tracheal ciliated columnar epithelium; after 6 months, the artificial trachea wall was covered with epithelium basically, and some ciliated columnar epithelium cells were found, which had the physiological function of the trachea. The transplanted PTFE artificial trachea could keep the stability of the biological mechanics performance, and could be used for the rabbit tracheal reconstruction.

PTFE artificial trachea can induce to form a tracheal tissue in the trachea tissues of recipients, each layer of the trachea is relatively complete and the experiment animals can be short-term survival.