Development of surgical protocol for implantation of tracheal prostheses in sheep Agnès Dupret-Bories, MD; Philippe Schultz, MD, PhD; Nihal Engin Vrana, PhD; Philippe Lavalle, PhD; Dominique Vautier, PhD; Christian Debry, MD, PhD
Purpose • Design and test in sheep an implantable tracheal prosthesis with rigid, immovable structure. • Perform biocompatibility studies before designing a laryngeal prosthesis. • Relevance • Disability resulting from total laryngectomy is a public health problem. • Significant difficulties with social reintegration. • Tracheostomies must be maintained for life.
Methods • Tracheal prostheses manufactured: • 400 to 500 μm diameter. • Mixture of titanium beads. • Using 5 different methods, prostheses were implanted in 11 sheep. • Daily clinical follow-ups, biweekly endoscopic follow-ups, and posteuthanasia histological analyses were performed.
Histological examination of central third of animal 4’s tracheal prosthesis. Lumen is covered with simple squamous epithelium. Endoscopic evaluation of animal 2 on day 55 showed large endoprosthetic lumen with good application of silicon tube.
Histological exam of middle of animal 11’s prosthesis. Squamous epithelium is present in lumen and pores are infiltrated by fibrovascular tissues. Microscopic view of animal 6’s prosthesis after muscle implantation. Pores between beads are infiltrated by mature connective tissue composed of fibroblasts. Microscopic view of animal 11’s prosthesis. Vascularized fibrous tissue filled in pores of titanium prosthesis.
Conclusions • Optimal surgical protocol for tracheal prosthesis implantation was established: 1. Precondition prosthesis. 2. Graft endoluminal epithelium. 3. Implant trachea using silicone tube for calibration. • Long-term study of tracheal prostheses implanted by this technique will be performed soon.