Reactivity Study of a Biodegradable Polydioxanone Tracheal Stent in a Rabbit Model.

Abstract Introduction The objective of this study was to evaluate tracheal reactivity induced by a biodegradable polydioxanone tracheal stent. Materials and methods Twenty-two rabbits were divided into 3 groups assigned to different survival times (30, 60 and 90 days post-implantation). A biodegradable stent was implanted in each animal, except for 1 from each group (negative control). Implantation was performed through a small tracheotomy under fluoroscopic control. CT and histopathological studies were scheduled at the end of survival times. Results No animal died during the procedure or follow-up. The stent had disappeared in 100% of the cases at 90 days, in 50% at 60 days, and in none at 30 days. CT studies revealed a greater tracheal wall thickness at 30 days than at 60 and 90 days (1.60 ± 0.41 mm in the central part of the stent versus 1.11 ± 0.18 and 0.94 ± 0.11; P = .007, respectively). No granulomas were observed on histopathology. Some degree of histological changes were noted at 30 days, which had reduced at 60 and 90 days. Differences were also found in both CT and histology between animals in which the stent was present and animals in which it had degraded. Conclusions Polydioxanone stents produce a mild reaction that reverts with tracheal degradation. The use of these biodegradable stents in benign tracheal disease is promising.