Experimental study of tracheal patch reconstruction with a covered expandable metallic stent

Abstract

Background. We evaluated the efficacy of tracheal patch reconstruction with a covered expandable metallic stent (EMS) with omentoplasty. Methods. After resecting the right half of the circumferential wall of two tracheal rings in adult beagle dogs, we inserted a covered EMS to reconstruct the defect interiorly. Then, through laparotomy, we made an omental pedicle flap and wrapped it around the EMS-interposed area. For comparison with the group without omentoplasty, we periodically examined the healing process macroscopically and histologically. Results. Bronchofiberscopic observations revealed that incorporation of the covered EMS progressed with the passage of time and tracheal luminal patency was maintained well in both groups. However, polyplike granulation developed gradually at both ends of the EMS. Histologically, epithelium was regenerated in the patched area 4 weeks postoperatively and the area was covered with pseudostratified ciliated epithelium at 12 weeks postoperatively. Quantitative analysis of the macroscopic and histologic findings showed that the inflammatory polyps were reduced and epithelialization was promoted in the group with omentoplasty. Conclusions. Tracheal patch reconstruction with a covered EMS, when combined with omentoplasty, promoted early epithelial regeneration and suppressed the development of inflammatory polyps.