Cryopreserved, Irradiated Tracheal Homograft Transplantation for Laryngotracheal Reconstruction in Human Beings

Abstract

Subglottic tracheal stenosis is a common clinical entity. Management in severe cases is often problematic. Various techniques for tracheal replacement have been used with varying degrees of success. In this study we used cryopreserved, irradiated tracheal homografts, the use of which in human beings has not been reported previously. In a sterile setup, the tracheas were harvested from donor cadavers within 24 hours of death. The grafts were initially kept at 57°C for 20 minutes; they were then placed in a −70°C chamber for another 2 to 3 days or more and were irradiated to 25 kGy (2.5 million rad). Finally, the grafts were stored at −70°C until usage. Seven patients underwent the surgery, but only 4 are presented here. In the remaining 3 patients, the follow-up time was too short to be evaluated. Four patients, 2 male and 2 female (aged 2-40 years, mean 16 years), with severe subglottic tracheal stenosis underwent segmental tracheal graft reconstruction. Immunosuppressant medications were not given to any patient. Follow-up ranged from 18 to 20 months. Three patients successfully underwent decannulation, and 1 patient had local infection and dislodgment of the intraluminal stent with subsequent restenosis. The postoperative tracheal lumen appeared to be near normal, with histologic evidence of normal respiratory epithelium at the grafted site. In conclusion, cryopreserved, irradiated tracheal homograft transplantation is a valuable alternative for subglottic tracheal reconstruction.

Fate of mucosal healing in transplanted deep frozen irradiated tracheal homograft

“…It is probably reasonable to believe that the remaining epithelium and subepithelial structures of the donor trachea might slough off shortly after transplantation. This may explain why there was no graft‐vs‐host reaction or graft rejection in the previous report by Kunachak et al 2 The postoperative macroscopic and microscopic appearance of normal tracheal mucosa most likely reflected migration of the recipient tracheal mucosa onto the de‐epithelialized framework of transplanted donor trachea. This hypothesis was supported by genomic difference between the mucosa of the tracheal graft pre‐ and postoperatively, and genomic compatibility between the recipient mucosa and regenerated mucosa at the transplanted site postoperatively.…”

“…Thirty samples from six sets of specimens, acquired from the tracheas of six donors and the corresponding recipients, each set consisting of five samples of tracheal mucosa, were studied. Sample 1 was taken from deep‐frozen irradiated donor tracheal homograft (described previously 2 ) just before transplantation; sample 2 was taken from the recipient area adjacent to the operating field; sample 3 came from the grafted site eight months postoperatively; and samples 4 and 5 were from the donor trachea and the transplanted site eight months postoperatively.…”

“…2 Macroscopically, good endoluminal healing has been reported. 2 Microscopically, the transplanted site has demonstrated healed tracheal mucosa overlain with pseudostratified ciliated columnar epithelium. However, the exact source of the epithelium is not known.…”

“…One of the most promising methods of reconstruction is tracheal homograft transplantation using either chemically processed 1 or cryopreserved irradiated homograft 2 . Macroscopically, good endoluminal healing has been reported 2 . Microscopically, the transplanted site has demonstrated healed tracheal mucosa overlain with pseudostratified ciliated columnar epithelium.…”

“…A s long as subglottic‐tracheal stenosis remains a clinical problem, novel methods of correction will probably appear periodically in the literature. One of the most promising methods of reconstruction is tracheal homograft transplantation using either chemically processed 1 or cryopreserved irradiated homograft 2 . Macroscopically, good endoluminal healing has been reported 2 .…”