Experimental Research Of Tracheal Allotransplantation With Cryopreserved Grafts

Clinically extensive tracheal stenosis caused by congenital disease, benign or malignant tumor, inflammation and other reasons is common, and the treatment is long-section tracheal resection and reconstruction which has long been a difficult surgical issue.Physiologically there is no artificial prosthesis, autogenous or homo-loguous tissues which work like human trachea, so tracheal allotrans-plantation is the best option which is also the hot research field at home and overseas recently. However, many difficulties such as preservation and revascularization of donator's trachea and immunologic rejection after transplantation, need to be resolved, before tracheal allotransplantation is used clinically.For the purpose of mentioned above, we underwent the following experiments:Different cryoprotective agents used commonly at present were selected for the protection of tracheal fragments of dogs. After frozen in a programed freezer and stored in liquid nitrogen at different intervals, tracheal fragments were thawed and inspected by histopathology, electron microscope and enzyme histochemistry to compare their viabilities. By the examination of fiberoptic bronchoscopy, histopathology and microangio-graphy, the measurement of tracheal mucosal blood flow and the calculation of survival rate and percentage of patency, the viability of graft status of autograft tracheas wrapped in one-sided sternocephalic muscle flap and two-sided sternohyoid-sternothyroid muscle flap with variant length, allograft tracheas without cryopreservation or cryopreservated at varying intervals also wrapped in one-sided sternocephalic muscle flap and two-sided sternohyoid-sternothyroid muscle flap, autograft tracheas without wrapped in muscles were evaluated in dogs.The results demonstrated:...