Sa2009 DEVELOPMENT OF A PER ORAL TRANSESOPHAGEAL ENDOSCOPIC CRUROPLASTY (POTEC) IN AN ACUTE PORCINE MODEL

Abstract

Transluminal and intramural endoscopic procedures continue to increase in type and variety. Notably, POEM and ESD are now performed regularly in many centers. These procedures have led to additional diagnostic and therapeutic procedures in the extraluminal space via submucosal tunneling. Using an acute porcine model, our goal was to develop a procedure to approach the diaphragmatic hiatus and perform a cruroplasty via an esophageal tunnel. The specific aims were to determine the ideal location for access, ease of display of anatomy, feasibility of the cruroplasty, and to define the key steps of the procedure. An acute study with IACUC approval and veterinary staff assistance using 4 Yorkshire pigs was completed by a single endoscopist. Submucosal tunnels were made at different locations (10 and 20 cm above GEJ) in two animals, one prone and the other supine, and suturing of crura attempted. Lessons from these cases informed the latter two procedures. A 5cm submucosal tunnel was created posteriorly. The mediastinum was entered 2cm into the tunnel via myotomy and trans-mural incision sizable enough to accommodate the suturing device. From within the mediastinum, the esophagus was followed to the hiatus requiring dissection of connective tissue to allow for identification of both vagus nerves and crura on either side of the hiatus. One suture was placed after taking two bites from each crura. Immediate euthanasia and necropsy followed. Safe trans-esophageal access, display of anatomy, and cruroplasty was reliably achieved in all animals. Trans-esophageal access was best performed dorsally about 10-12cm above the GEJ, with the animal in the prone position. One animal was attempted in the supine position and had to be repositioned during the procedure as this position altered ability to navigate the hiatus. An anterior approach to mediastinal access was attempted in one animal and also interfered with ease of identification of structures. Tunnels that were made 10cm proximal to the GEJ allowed for easier access and identification of structures than those made 20cm from the GEJ (directly assessed in the first two animals). Myotomy and mediastinal access was done from the end of a 5 cm tunnel. Attempts to stay in the mediastinum caused micropuncture and tension pneumothorax in the first animal, resolved by making a larger access point. Immediate necropsy showed successful cruroplasty without iatrogenic injury. POTEC procedure is feasible. The procedural steps are defined and mediastinal anatomy can be safely identified and avoided during suturing. The cruroplasty was shown to be successfully placed without iatrogenic injury on necropsy. A survival study will confirm the potential for clinical application, particularly in the treatment of GERD.Figure 2Photo of necropsy showing successful endosuturing of the crura from the superior view of the diaphragm.View Large Image Figure ViewerDownload Hi-res image Download (PPT)