Colonoscopy is the most reliable and effective examination method for colon diseases, and it is the goal of every colonoscopist to perform colonoscopy smoothly, quickly, safely and with low pain. From April 2001 to October 2007, based on the experience of others, the author switched to single-person operation to perform 1612 cases of colonoscopy, and hereby report the relevant operational experience as follows. 1, information and methods 1, 1 general information: this group of 1612 cases, 837 men and 775 women. The age ranged from 18 to 82 years. All of them were outpatients or inpatients of our hospital, and were seen for complaints of abdominal pain, diarrhea, abdominal distension or blood in stool, constipation, etc. 1, 2 Examination methods: Preoperative bowel preparation was routinely performed without any sedative and analgesic drugs. The PentaxEC3830FK electronic colonoscope was used for endoscopy. The patient was placed in the left lateral recumbent position. The main machine was located at the ventral bedside of the patient in the left lateral recumbent position, and the operator was located at the anal bedside of the patient, holding the manipulation part of the colonoscope in the left hand with the knob unlocked, and holding the endoscope body at 500px-750px from the anal opening with the right hand. The left and right hands work closely together to coordinate the rotation and angle of the endoscope according to the direction of the intestinal cavity, follow the cavity into the mirror, less inflation, hook and pull, pumping and rotation into the mirror when appropriate, change the position and abdominal pressure when necessary, keep the mirror body straight, shorten the intestinal tube state, prevent the mirror body from knotting, and avoid abdominal pain of the patient. The assistant passes the items, lubricates the mirror body and presses the abdomen when necessary. Indicators of success: insertion to the ileocecal region or the end of the mirror did not reach the ileocecal region, but the lesion was found and the purpose of the examination was achieved [1]. The success rate of insertion was 98.8%, and the insertion time ranged from 4 to 35 min, with an average of 11.4 min. The patients basically had no pain or mild abdominal pain and abdominal distension. In another 19 cases, the colonoscopy was not completed because of obvious abdominal pain, and one of them had a history of abdominal surgery and was later diagnosed with intestinal adhesions, and an adhesion cord between the colon and the abdominal wall was seen intraoperatively. No complications such as perforation occurred in the whole group. 3. Discussion Taking a straight mirror body and shortening the intestinal canal is the key to smooth, fast, safe and low pain colonoscopy operations [1], and the single operator method helps to achieve these purposes because of good coordination and more convenient use of some special maneuvers [2]. Through the practice of 1612 patients, the author has the following experience and skills in different intestinal segment access methods: 3.1 Recto-big colon and b-descending colon migration: by continuously rotating the mirror around the lumen and straightening the mirror body, the intestinal tube below the b-descending is basically set on a 750px mirror body. The purpose of rotating the mirror is to turn the direction of the intestinal cavity to the top or bottom of the field of view depending on the change of the intestinal cavity, and then adjust the up and down knobs (sometimes need to adjust the left and right knobs) to expose the intestinal cavity into the mirror. Repeatedly pulling back combined with shaking the mirror, shaking the mirror can make the mirror body straight, the overgrown, free sigmoid colon overlap on the mirror body, laying the foundation for the next step into the mirror smoothly. The medical education network collects and organizes 3,2 rotary approach: when the intestinal cavity is in the field of view and there is no obvious turning, do not send the mirror directly forward, but use the rotary approach. The method is to hold the mirror with the right hand and rotate the mirror left and right along the longitudinal axis of the mirror while entering the mirror. The advantage is that the hand force can be accurately transferred to the front of the endoscope to prevent the mirror body from bowing in the body, thus avoiding abnormal pain caused by elongation of the free bowel and preventing the formation of collaterals; it can also reduce the force of the right hand into the mirror and complete the operation more easily. The principle is especially like holding a needle sizzling needle through the skin: direct needle entry requires force, and it is easy to make the needle bend, such as gently rotate it is easy to maintain a straight line into. This method is simple, practical, especially suitable for use when passing through the descending and sigmoid colon. 3, 3 colonic splenic flexure: if the splenic flexure is overly twisted and the splenic flexure is at an acute angle, only visible flexural folds cover the entire intestinal cavity, then blindly slide the mirror can cause patient pain, intestinal wall damage, and even cause perforation. The right lateral position can be changed to follow the lumen into the mirror, or by rotating the mirror to turn the crease to the bottom of the field of view, send the front end of the endoscope to the crease, the left hand will rotate the large knob downward, the mirror end presses the crease, while hooking and pulling, slightly receding the mirror, so that the splenic flexure is bluntly angled, exposing the intestinal cavity into the mirror, while the left hand returns to the angle knob. This method can also be used when it is difficult to cross the hepatic flexure with the enteroscope. 3, 4 ascending colon: when the front end of the endoscope is just over the hepatic flexure, the intestinal lumen of the ascending colon is often fully exposed, but it is difficult to enter the mirror, or even backward instead of in. Mostly because the hand force can not be transferred to the front end of the endoscope, the colonoscope in the transverse colon is bowed down. At this time, the mirror should be retracted first to straighten the mirror body, ask the assistant to press the patient’s umbilicus, and push the top with force in the direction of the saber rib arch to resist the sagging of the colon, and then enter the mirror can be successful.