Demonstration of the role of an implantable bioscaffold in airway reconstruction: a pilot study utilizing an animal model.

INTRODUCTION: Laryngotracheal reconstruction is a common procedure to repair subglottic stenosis. Despite a success rate upwards of 85%, this procedure has significant morbidity associated with it, specifically with the site of the graft harvest and recurrence of stenosis. We propose that a recently described cellular bioscaffold xenograft may be useful in reducing these complications.

METHODS AND MATERIALS: 10 Sprague Dawley rats were divided into 2 groups of 5. One group underwent incision through the cricoid and the first two tracheal rings followed by primary closure (G1); the second group underwent incision through the cricoid and the first two tracheal rings followed by placement of the xenograft (G2); additionally, a specimen was harvested from an animal which did not undergo any surgical procedure to compare to the two surgical groups. Specimen harvest occurred on post-operative days 1, 7, 14, 21, and 28.

RESULTS: 6 of 10 animals provided usable data. All animals receiving the xenograft survived until the time of specimen harvest. Only 1 animal undergoing primary closure survived beyond post-operative day one. On histology review, the xenograft animals showed a progressive decrease in fibrosis relative to the animals that underwent primary closure. On POD 28, restoration of the respiratory epithelium and intact basement membrane was noted in the xenograft group.

CONCLUSION: We believe that this pilot study shows the potential of utilizing bio-implantable biomaterials, specifically a cellular bioscaffold which encourages the ingrowth of native tissue instead of fibrosis. Histologic analysis shows that use of the xenograft can initiate the proliferation of native tissues decreasing the amount of fibrosis present post-operatively, although significant further analysis is needed before definitively concluding that this approach is superior to utilization of a graft.