Experimental study of a new tracheal prosthesis: pored Dacron tube.
OBJECTIVE
This study was designed to evaluate how various sizes and densities of pores in Dacron tubing might enhance its utility as a tracheal prosthesis.


METHODS
A vascular prosthesis made of knitted external velour polyester was prepared for pore formation with a laser. The first set compared different pore sizes (300, 500, and 700 microm) and pore densities (25/cm(2) or 100/cm(2)). Grafts were reinforced with an externally heat-sealed silicone ring. The second set tested grafts with a pore density of 64/cm(2) and a pore size of 500 microm internally reinforced with a stainless-steel spiral stent. In all experiments, a canine mediastinal trachea 10 cartilage rings in length was resected, and the prosthesis was then implanted with an omental flap.


RESULTS
Lower pore size and density (300 microm, 25 pores/cm(2)) led to essentially no tissue ingrowth. Larger pore size (700 microm) and low density (25 pores/cm(2)) led to rapid and excessive ingrowth of granulation. Midrange pore size (500 microm) and high density (100 pores/cm(2)) invited steady tissue ingrowth, but marked luminal stenosis eventually developed. Stent-reinforced prostheses with 500-microm pores at 64 pores/cm(2), as used in the second set, maintained an average patency rate of 60% or more (range, 20%-100%) at least 12 months after implantation.


CONCLUSIONS
Our data show that porosity is a key factor for tissue growth through our Dacron tracheal prostheses. This artificial trachea model has led to long-term survivors up to 27 months after the operation and seems promising as a basic model for clinical tracheal repair.
Department of Surgery, Division of Chest Surgery, St. Marianna University School of Medicine, 2-16-1 Sugao Miyamae-ku, Kawasaki, Japan. h2tukada@marianna-u.ac.jp
Hisashi
H
Tsukada
Hiroaki
H
Osada
D000818:Animals; D001999:Bronchoscopy; D004285:Dogs; D004848:Epithelium / Q000254:growth & development; D020007:Implants, Experimental; D011093:Polyethylene Terephthalates; D016062:Porosity; D019736:Prostheses and Implants; D011474:Prosthesis Design; D014132:Trachea / Q000601:surgery
D011093:Polyethylene Terephthalates