During conventional colonoscopy with polypectomy, the colon lumen is insufflated with air, which flattens polyps and thins the wall of the colon. These two factors increase the risk of procedural complications such as bleeding and perforation. In order to counter these drawbacks a technique, which involves the injection of saline into the submucosal area beneath the polyp, is commonly used for the resection of large flat polyps. Theoretically, the injection creates a "safety cushion" that reduces the risks of accidental ensnarement of the muscularis propria, which can lead to iatrogenic perforation and thermal injury to the deeper tissue layers. However, the submucosal injection technique is cumbersome in patients with particularly large polyps as multiple injections are often necessary, which can blur the line between normal and abnormal tissue.