Endoscopic knot tying: In vitro assessment in a porcine stomach model

Figure 1 Endoscope. A: The “in vitro” pig stomach model with the endoscope in place; B: View over muscularis propria from the gastric lumen in the submucosal space created by endoscopic submucosal dissection. Muscularis propria is about to be punctured (“peritoneoscopy”); C: Endoscope outside of the stomach simulating peritoneoscopy, with the dilated balloon in the working channel.

Figure 2 Natural orifice translumenal endoscopic surgery. A: Puncture of the mucosa from the submucosal space on the right side of the incision and passing a guidewire into the gastric lumen; B: The guidewire traverses the mucosa on the right side of the incision, both ends are outside; C: Surgical wire replaces the guidewire first on the right side, then is passed through both sides after replacing the guidewire on the left side; D: A loop formed outside is pushed with the endoscope (here at the rim of the transparent cap) at the mucosal incision so as to tighten the knot; E Cutting the wire ends; F: The final aspect of the surgical knot.