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A new tracheal prosthesis made from collagen grafted mesh.

The authors studied the efficacy of a new tracheal prosthesis made from mesh. The prosthesis, 50 mm long and 18-22 mm in diameter, is made from a Marlex mesh cylinder reinforced with a continuous polypropylene spiral that is grafted and coated with porcine collagen to increase its biocompatibility and provide an airtight seal during the initial implantation stage. Circumferential surgical resection and replacement of a seven to nine ring segment of the cervical trachea was performed in 20 adult mongrel dogs. At the time of surgery, a silicone tube was inserted into the tracheal prosthetic lumen to promote secretory transportation until the prosthesis was covered with host tissue. The silicone tube was removed during fiber bronchoscopy 1 month after surgery. With the exception of the prostheses in 3 dogs that died of unrelated causes, all were infiltrated by connective tissue and incorporated completely by the host. One of these 17 dogs died of suffocation caused by luminal stenosis 2.5 months after surgery, but the others survived until they were killed at more than 6 months. The luminal surfaces of the reconstructed tracheae were covered with respiratory epithelium to varying degrees, and in one dog killed at 22 months after surgery, confluent epithelization throughout the length of the prosthesis was confirmed histologically. In eight dogs, prosthetic luminal stenosis occurred because of overgrowth of granulation tissue, which generally was mild in all but three dogs. The authors conclude that this tracheal prosthesis is highly biocompatible and shows promise for clinical application.