The difference between e-rectoscopy and colonoscopy: 1. the examination parts are different, colonoscopy can examine all the intestines except the small intestine, while e-rectoscopy only examines the rectum, similar to a longer anoscope. 2. the average time for a long colonoscopy is about 30 minutes, and if a suspicious lesion is found that requires pathological examination, its time will be longer; e-rectoscopy takes less time, about 10 minutes. 3. the comfort It is different, there are many parts of colonoscopy, and patients need to inflate and check at the same time during the colonoscopy, which is more painful than e-rectoscopy. In addition, colonoscopy is usually performed from the rectum to the colon to the cecum, and then to the end of the ileocecal part about 10 cm. Therefore, what is seen and detected by the colonoscopy can completely replace the e-rectoscopy, so there are many differences between e-rectoscopy and colonoscopy.