Experimental Replacement of the Thoracic Esophagus with a Bioabsorbable Collagen Sponge Scaffold Supported by a Silicone Stent in Dogs

Abstract

We manufactured an esophageal prosthesis made of a collagen sponge supported by an inner silicone tube. The collagen was derived from porcine skin and was crosslinked by dehydrothermal treatment. We implanted our prosthesis in nine dogs after resecting a 5 cm length of the thoracic esophagus. Intravenous hyperalimentation was performed for 4 weeks after the surgery. After 29 days, the inner silicone tube was removed endoscopically and oral feeding was restarted immediately. All nine dogs survived more than 1 month, and three of the nine dogs survived for more than 1 year. Endoscopically, the luminal surface of the regenerated esophagus was covered with a lustrous, smooth mucosa, but stenosis was observed in the midregion of the regenerated esophagus. Microscopically, no foreign material remained at the reconstructed site 1 month after surgery; the collagen sponge was absorbed and replaced by host tissue. Complete epithelization was observed within 3 months. Regeneration of the lamina muscularis mucosae, esophageal glands, and skeletal muscle were observed near the anastomoses. Our artificial esophagus holds promise for esophageal reconstruction in a clinical setting, even in the thorax.