Difficult colorectal polypectomy: Technical tips and recent advances

Figure 5 Underwater endoscopic mucosal resection for a polyp involving appendiceal orifice. A: Endoscopic image showing a 15-mm sessile polyp involving the appendiceal orifice; B: Magnifying narrow-band image showing a type 1 polyp of the Japan Narrow-band Imaging Expert Team classification with open pit pattern. The most likely diagnosis was sessile serrated lesion; C: Underwater snaring without submucosal injection; D: Mucosal defect after completed underwater endoscopic mucosal resection.