Depth of endoscopically placed sutures: an experimental study in a human cadaver model.

BACKGROUND: Endoscopic suturing devices offer interesting access for interventional procedures used on the gastrointestinal tract. For the time being, the main indication is endoluminal suturing at the gastroesophageal junction for the management of gastroesophageal reflux disease. There is some evidence that endoluminal endoscopic suturing offers an alternative to the closure of esophageal fistulas and to the fixation of feeding tubes and stents in the near future. A review of the literature found no anatomic data on wall layers stitched by sutures. The aim of this study was to determine the depth of sutures placed endoscopically in the esophagus of a human cadaver model.
METHODS: Altogether, 62 sutures were placed in the esophagi of 10 cadavers (complete exenterative cadaver model) at three different suction levels (0.4, 0.6, and 0.8 bar) using the EndoCinch suturing machine. After preparation of the esophagus from its mediastinal bed, all sutures were fixed in formalin and stained with hematoxylin and eosin for histologic examination.
RESULTS: No sutures were placed in the mucosa alone. As observed, 1.6% were placed in the submucosa, 4.8% in the circular muscularis propria, and 56.5% in the longitudinal muscularis propria, with 37% placed transmurally. At a suction level of 0.4 bar (0.6, 0.8 bar), 0% (0%, 1.6%) were placed in the submucosa, 3.2% (0%, 1.6%) in the circular muscularis propria, and 11% (25.8%, 12.9%) in the longitudinal muscularis propria, with 12.9% (6.5%, 17.7%) placed transmurally.
CONCLUSIONS: This study reports, for the first time, a systematic examination of the depth of sutures placed endoscopically in the esophagus. Most of the sutures were found in the muscular wall of the esophagus at a suction level of 0.6 bar. Also, transmural placements were seen. Reduction of suction pressure may lead to a decrease in transmural sutures.