Tracheoplasty using a metallic fusiform centrally-doubled coiled stent for a major tracheal defect in rabbits

Abstract

Background/PurposeThe long-term survival rate of rabbits treated with a fusiform metallic coil for a large tracheal wall defect is 60%. In the present study, the central half of a simple coil was covered by a double coil to prevent the ingrowth of the surrounding connective tissue and to provide a sutureless fixation of the coil to obtain a further increase in the survival rate. Study DesignThe anterior half of the tracheal wall was removed for a longitudinal length of 6 tracheal rings to make a large tracheal defect. Metallic coils were placed into the tracheal lumen through the wall defect. The doubly-coiled portion was designed to fit the length of the defect to eliminate the need for suture fixation. The survival at two months after the operation, endoscopic findings and histological changes were evaluated. ResultsAll 6 rabbits treated with a centrally-doubled coiled stent survived without major respiratory trouble for at least 2months. Endoscopic examinations performed 1month after the operation revealed an irregular coating of reddish granulation tissue inside the coil, and a wet portion was aspirated. The tracheal defect was replaced with fibrous tissue, but neither a complete epithelialization nor cartilage formation was observed. ConclusionThese results suggest that the metallic coil was useful to obtain an improvement in the survival of rabbits with a large tracheal wall defect. Therefore, this new coil might be indicated for the treatment of tracheal wall defects.