Comparative experimental study of esophageal wall regeneration after prosthetic replacement

This study compares three prosthetic materials for potential use in patching and bridging congenital and acquired esophageal defects. The study was divided into two parts. In the first part, full-thickness, 6-cm2 cervical esophageal defects were induced in three groups of young mongrel dogs and were replaced with patches of lyophilized dura mater (Lyodura), polyethylene terephthalate (Dacron), or expanded polytetrafluoroethylene (PTFE). The dogs in the Lyodura subgroup were scheduled to be sacrificed after 1, 2, 4, 8, and 12 weeks and the dogs in the PTFE and Dacron subgroups were sacrificed after 1, 2, 3, 4, 6, and 7 months. The patched esophagus was removed for gross and microscopic examination. In the second part of the study a segment of the esophagus was excised in another three groups of dogs and replaced with 3 x 2 cm tubes of Lyodura, Dacron, or PTFE. Here the follow-up was prolonged and included radiological, endoscopic, and histological assessment. The dogs of each subgroup were scheduled to be sacrificed after 6, 8, and 12 months. Results indicated that lyophilized dura mater covered and neoepithelialized the patched area within the shortest period of time without foreign body reaction and with only slight collagen deposit, resulting in a ductile repaired esophageal wall. Therefore, its use may be considered for replacement of partial esophageal defects. For complete circumferential defects, the present study and our review of the literature showed that there is as yet no ideal prosthetic material that promotes good incorporation but is not prone to stenosis. Further studies in this area are required.