What method can assure that the muscular layer of the bowel wall is not affected during polypectomy?

Using saline injection under the polyp is a technique that helps to ensure the muscular layer of the bowel wall remains intact during polypectomy. This method involves the injection of saline into the submucosal layer beneath the polyp. The infusion of saline creates a cushion that elevates the polyp away from the muscularis propria, allowing for safer resection. By maintaining this distance, the risk of damaging the underlying muscle layer is significantly reduced, which can lead to complications such as perforation.

In contrast, full-thickness excision would involve cutting through the entire bowel wall, which is not ideal when the goal is to avoid affecting the muscle layer. Cauterization at high temperatures could potentially damage deeper tissues and the muscular layer, as heat can extend beyond the target area. Mechanical disruption, while it may remove a polyp, does not provide the controlled and careful approach of saline injection, increasing the likelihood of damaging the underlying structure. Therefore, the use of saline injection stands out as the safest method to preserve the muscle layer during a polypectomy.