Laryngotracheal reconstruction with tracheal patch allografts.

The capacity of tracheal allotransplants in providing optimal tissues for laryngotracheal repair was studied in an animal model. Segments of cervical trachea could be revascularized completely when wrapped in a receptor fascia flap in immunosuppressed rabbits. In phase I the revascularized tracheas were incised longitudinally and transformed into four different patches after a 14-day revascularization period. The blood supply toward the four patch designs was examined with angiography. The patch designs that showed a vascularization over at least 75% of their mucosal surface area were used in phase II to reconstruct extended anterior laryngotracheal defects. The morphologic characteristics of the tracheal patches when used inside laryngotracheal defects were studied using radiographic, angiographic, and histologic techniques. The revascularized allograft patches that were fully supported by tracheal cartilage were most suitable to repair anterior laryngotracheal defects in this animal study. This model allowed us to define the tissue characteristics necessary for obtaining a combination of primary healing and optimal luminal support in the repair of laryngotracheal defects.