INTRODUCTION: Safe esophageal closure remains a challenge in transesophageal Natural Orifice Transluminal Endoscopic Surgery (NOTES) procedures. Suturing or t-tag devices are time consuming and risk organ injury due to their blind deployment. Endoclips are difficult to place in the narrow esophagus and submucosal tunneling techniques do not necessarily prevent leakage of esophageal contents into the mediastinum or thorax. In this survival animal series, we demonstrate safe esophageal closure with a prototype retrievable, anti-migration stent.
METHODS: Nine Yorkshire swine underwent thoracic NOTES procedures. A double-channel gastroscope equipped with a mucosectomy device was used to create a small esophageal mucosal defect. A 5-cm submucosal tunnel was created and a needle-knife was used to incise the muscular esophageal wall and permit entry into the mediastinum and thorax. Mediastinoscopy and thoracoscopy were performed in all swine; lymphadenectomy was performed in 7 swine. A prototype small intestinal submucosal (surgiSIS®) covered stent was deployed over the mucosectomy site and tunnel. Three versions of the prototype stent were developed (Table 1). Pre-necropsy endoscopy was performed to confirm stent location and retrieve the stent. Explanted esophagi were sent to pathology for review.
RESULTS: Esophageal stenting was successful in all animals. Stent placement took 15.8±5 min and no stent migration occurred in any swine. Pre-necropsy endoscopy revealed ingrowth of esophageal mucosa and erosion at the proximal portion of Stent A. Mucosal inflammation and erosion was observed at the proximal site of Stent B. No esophageal erosion or pressure damage from high radial forces was seen during stent retrieval in the swine receiving Stent C. On necropsy, swine 5 had a 0.5cm peri-esophageal abscess. Histology revealed a localized lesion at the esophageal exit site consisting of acute inflammatory cells in the esophageal wall in swine 4, 7, and 9. The mucosectomy site was partially healed in 3 swine and poorly healed in 6. All swine thrived clinically, except a brief period of mild lethargy in swine 9 on postoperative day 3. This particular swine improved with short-term antibiotic therapy. The submucosal tunnels were completely healed and no esophageal bleeding or stricture formation was observed in any swine. All swine survived 13.8±0.4 days and gained weight in the postoperative period.
CONCLUSION: Esophageal stenting provides safe closure for NOTES thoracic procedures, but may impede healing of the mucosectomy site.
Table 1: Prototype Stent Specifications for Esophageal Closure
|Swine No||Diameter Proximal Cage||Diameter (body)||Stent Length, mm||Plastic covered proximal cage|
SIS/Plastic Covered body cage
|Plastic covered distal cage|
Session: Podium Presentation
Program Number: S042