Colonoscopy is a relatively intuitive and accurate examination method for checking colon and rectal lesions. It is a tube-like structure containing fiber-optic equipment that is inserted into the rectum and colon through the anus, and it can be used to observe rectal and colonic mucosal lesions through the electronic transmission of the pictures seen on the television, and it can detect inflammatory lesions, ulcerative lesions, and even neoplastic lesions of rectal and colonic mucosa, so it is equivalent to intuitive observation of the mucosal lesions. Colonoscopy is equivalent to visual observation of the lesions of the intestinal mucosa, and is a more accurate and objective means of examination of the intestinal tract.