3470 Widespread circumferential mucosectomy in the porcine esophagus–a pilot study.

Abstract

Endoscopic mucosal resection (EMR) is a procedure growing in significance as an alternative to surgery in the treatment of gastrointestinal mucosal lesions. Current EMR techniques are limited to lesions measuring less than 2 cm. Aim: To demonstrate that widespread circumferential mucosectomy up to 5 cm in length can be performed using a stripping method. Method: Eight, 60 kg anesthetized pigs were studied. The distal 5 cms of the esophagus was injected with 50% dextrose to create a lasting submucosal protective cushion. A strip of mucosa approximating 5 cm in length from the esophagogastric junction and 1 cm in width was marginated along its length and proximal end using a porcelain ball-tipped needle knife and prototype teflon backed monopolar scalpel (Olympus America, Inc., NY). The proximal end once undermined was grasped using forceps and stripped off the submucosal cushion in a distal direction. The distal end was then resected using a needle knife from a retroflexed position. This was repeated sequentially until the distal esophagus was circumferentially denuded of mucosa. Four pigs were sacrificed immediately after the procedure while two each of the remaining four animals were followed for two and four weeks. Result: Complete widespread circumferential mucosectomy was achieved in five animals with an average of four strips removed per pig. The average strip length was 5.5 cm(range 5-6 cm) and width 0.9 cm(range 0.6-1.2 cm). There were no procedural complications in the five animals. Mucosectomy was incomplete in the first two animals as the technique of mucosal stripping evolved with another animal experiencing a perforation early in this learning curve. The animals sacrificed immediately post-procedure showed histologically intact muscularis propria with some preservation of the submucosa and minimal associated edema and cautery injury. Repeat endoscopy of the surviving animals (4) showed healing with moderate (1) to tight (3) strictures at both two and four weeks. Conclusion: 1. Widespread circumferential esophageal mucosectomy can be performed endoscopically using a true stripping technique with preservation of the muscularis propria. 2. This technology has exciting potential clinical applications especially in the treatment of Barrett's esophagus. 3. The appropriate measures to prevent post-procedural stricture formation need to be further investigated and identified. (The Apollo Group: Sydney Chung, Peter Cotton, Christopher Gostout, Robert Hawes, Anthony Kalloo, Pankaj Pasricha, Thadeus Trus)