Endoscopic Double-Layer Closure with Mucosal Flap By Combination Use of Tissue Anchors and Metallic Clips -Application of ESD Technique for NOTES-

Abstract

Background: Tissue anchors related devices have a great potential as safe and cost effective suturing devices for various NOTES procedures. However, there are a few studies to seek the most reliable suture method by use of tissue anchoring devices. The aims of this study were to evaluate the efficacy of various suture methods with tissue anchors and to seek the most reliable closure for NOTES. Methods: A prototype of double T-bar suturing device (Olympus Medical Systems Co., Tokyo, Japan) was used for this study. The pressure required to cause air leakage was compared in six closure arms in ex vivo porcine stomach models. A gastrotomy was created with a 10 mm diameter punch in five arms (1)-(5). In the last arm (6), a 15 mm diameter semicircular mucosal flap was created with ESD technique and then the seromusclar tissue was punched in 10 mm diameter. Air flow volume was stabilized in 1.5L/min. The six closure arms were (1) single full-thickness suture with T-bar; (2) double parallel full-thickness suture with T-bar; (3) double parallel mucosal suture with T-bar; (4) double parallel seromusclar suture with T-bar; (5) double-layer suture with double T-bar (seromusclar suture) and double metallic clips (mucosal suture); (6) double-layer suture with mucosal flap by combination use of double T-bar (seromusclar suture) and double metallic clips(mucosal suture). Results: The mean pressures for air leakage were (1) 4.3; (2) 10.5; (3) 18.2; (4) 23.6; (5) 28.8; (6) 40.5; in mm Hg. The overall comparisons were significant by use of Kruskal-Wallis statistical analysis (p < 0.01). Conclusions: Endoscopic double-layer closure with mucosal flap produced the strongest closure in porcine stomach model. This method would be a promising technique for the clinical application of NOTES.