Stent placement provides safe esophageal closure in thoracic NOTES(TM) procedures

Abstract

Background: Safe esophageal closure remains a challenge in transesophageal Natural Orifice Transluminal Endoscopic Surgery (NOTES). Previously described methods, such as suturing devices, clips, or submucosal tunneling, all have weaknesses. In this survival animal series, we demonstrate safe esophageal closure with a prototype retrievable, antimigration stent.

Methods: Nine Yorkshire swine underwent thoracic NOTES procedures. A double-channel gastroscope equipped with a mucosectomy device was used to create an esophageal mucosal defect. A 5-cm submucosal tunnel was created and the muscular esophageal wall was incised with a needle-knife. Mediastinoscopy and thoracoscopy were performed in all swine; lymphadenectomy was performed in seven 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. Prenecropsy endoscopy confirmed stent location and permitted stent retrieval. Explanted esophagi were sent to pathology.

Results: Esophageal stenting was successful in all animals. Stent placement took 15.8 ± 4.8 minuted and no stent migration occurred. Prenecropsy endoscopy revealed proximal ingrowth of esophageal mucosa and erosion with Stent A. Mucosal inflammation and erosion was observed proximally with Stent B. No esophageal erosion or pressure damage from proximal radial forces was seen with Stent C. On necropsy, swine 5 had a 0.5-cm periesophageal abscess. Histology revealed a localized inflammatory lesion at the esophageal exit site in swine 1, 3, and 9. The mucosectomy site was partially healed in three swine and poorly healed in six. All swine thrived clinically, except for a brief period of mild lethargy in swine 9 who improved with short-term antibiotic therapy. The submucosal tunnels were completely healed and no esophageal bleeding or stricture formation was observed. All swine survived 13.8 ± 0.4 days and gained weight in the postoperative period.

Conclusions: Esophageal stenting provides safe closure for NOTES thoracic procedures but may impede healing of the mucosectomy site.

Fig. 1

Stent A: erosion and ingrowth of esophageal mucosa at the proximal cage of the stent. The SurgiSIS material covering the stent is partially degraded revealing the underlying plastic

Fig. 2

Stent B: proximal mucosal erosion and inflammation

Fig. 3

Partial healing of a mucosectomy site is seen here as an ovoid defect in the mucosa. The proximal portion of the esophagus (right side of image) demonstrates tissue ingrowth at proximal portion of the stent