Objective: To investigate the feasibility of tracheal reconstruction with a prosthesis made of memory alloy coated with collagen sponge in mongrel dogs.
Method: The basic skeleton of the prosthesis was knitted with Ni-Ti memory alloy wires. The tubular mesh was sealed with polyurethane membrane and then inner and external walls of the lumen were coated with collagen sponge. Cervical trachea segmental reconstruction was performed in 8 mongrel dogs with these prostheses. The efficacy of the implanted prostheses were periodically evaluated after operation using x-ray, tracheoscopy and specimen microscope examinations.
Results: One dog died of prosthesis dislocation 10 days after operation, another was killed 45 days later because of anastomotic stenosis. 6 dogs survived more than 90 days and the longest one lived for 150 days. Its implanted prosthesis was completely incorporated with the recipient tissue, where re-epithelialization occluded on anastomotic sites. The tracheal lumen was patent.
Conclusion: This memory alloy tracheal prosthesis has been proved useful for reconstruction of large, circumferential tracheal defects, although its long-term safety and efficiency need to be confirmed.