There are many types of small bowel diseases, such as infectious inflammation (bacterial, viral, parasitic, etc.), Crohn’s disease, tumor or vascular lesions, etc. Although there are many examination methods, such as whole gastrointestinal barium meal, small intestine air-barium double imaging, nuclear scan, selective arteriography, B ultrasound, CT, MRI, PET, etc., these methods have solved some of the clinical problems, but they all have their limitations. With the rapid development of endoscopic technology, the capsule endoscopy (CE) produced by Gxv EN, Israel, has been used in clinical practice since 2001, which can observe the whole small intestine and obtain imaging data of the whole small intestine, but the field of view of CE is only 140°, which has a certain blind area and is easy to miss the diagnosis, and if the capsule is embedded, it cannot be accurately located, biopsied and treated. In addition, it is suitable for those with relatively large bleeding or suspected intestinal obstruction, and its application is somewhat limited. 2001, Dr. Borden Yamamoto of Japan was the first to carry out double-balloon electronic small intestinal microscopy, which has the characteristics of wide field of view and clear image, and can perform biopsy, mucosal staining to mark lesion sites, submucosal injection, polypectomy, balloon dilation, and stent installation, etc. It has become an important tool for the diagnosis and treatment of small intestinal diseases. and increasingly presents its excellent functions. Because only a few hospitals in Zhejiang Province have carried out double balloon small bowel microscopy, and there is still a gap in Ningbo city. Therefore, this study aims to evaluate the diagnostic value of double-balloon electronic small intestine microscopy on small intestine diseases. Our hospital introduced double-balloon electronic small bowel microscopy in July 2014, and from July 2014 to August 2015, 20 patients suspected of small bowel disease were hospitalized for double-balloon small bowel microscopy. In this paper, we review and analyze the microscopic performance and lesion detection rate of double balloon small bowel microscopy on patients with different clinical symptoms such as unexplained gastrointestinal bleeding, abdominal pain and other incomplete intestinal obstruction and diarrhea, observe the complications, and evaluate the clinical value of double balloon small bowel microscopy in the diagnosis of small bowel diseases. I. Materials and methods 1. General data From July 2014 to August 2015, a total of 20 patients with suspected small bowel disease underwent double-balloon electronic small bowel microscopy. Among them, 16 cases were male (18-64 years old), with an average age of 41.0 years, and 4 cases were female (36-44 years old), with an average age of 40.0 years. Among the 20 patients, 8 had abdominal pain of unknown origin, 7 had gastrointestinal bleeding of unknown origin, 4 had abdominal pain with black stool, and 1 had incomplete small bowel obstruction of unknown origin. The patients were examined by gastroscopy, colonoscopy, whole abdomen CT, abdominal B-ultrasound, abdominal CT, etc., and no positive lesions were found. The whole endoscopic operating system consists of four parts: endoscope, main unit, outer sleeve and air pump. Patients were prepared with bowel cleansing before entering the scope, and all patients completed a preoperative interview and signed an informed consent form. A double-balloon small bowel microscopy was performed under intravenous anesthesia with isoproterenol + fentanyl for transoral access. Half an hour before the transanal approach, pethidine injection 50mg + diazepam injection 10mg + scopolamine injection 10mg was administered intramuscularly. After the head of the endoscope entered the horizontal section of the duodenum, the balloon at the end of the endoscope was inflated and fixed in the intestinal canal, and then the outer casing was pushed 50 cm into the front of the endoscope along the body of the endoscope, and then the balloon of the outer casing was inflated and the endoscope, the outer casing and the intestinal canal were fixed relative to each other, and then the endoscope and the outer casing were slowly straightened; then the balloon at the front of the endoscope was deflated and the endoscope was inserted deeper into the intestine until The endoscope is then deflated at the front end of the endoscope and inserted deeper into the intestine until it is impossible to continue to enter the scope. Repeat the above-mentioned inflation, deflation and sliding of the cuff, together with the rotation of the mirror and hook and pull, to advance the mirror to the deep small intestine. If no abnormality is found through the mouth or anus, the site reached will be marked by submucosal injection of dye to indicate the depth to be reached in the next examination through the opposite side to complete the bilateral examination. In some patients with lesions, tissue was taken under the microscope for pathological examination. During and after the operation, some patients may experience nausea, throat discomfort, mild abdominal pain, and abdominal distension, etc., all of which can be improved with symptomatic treatment or can be relieved by themselves. There were no other serious complications such as gastrointestinal bleeding, acute pancreatitis, tracheal aspiration, anesthesia accident, etc. All patients with microscopic biopsy did not have perforation and obvious gastrointestinal bleeding. 5 of 20 patients with suspected small bowel disease had first transoral access to the mirror and 15 had first transanal access to the mirror; 2 patients received bilateral access to the mirror. The detection rate was 75.0%, including 4 cases of intestinal Crohn’s disease, 3 cases of nonspecific inflammation of jejunum, 4 cases of terminal lymphoid follicular hyperplasia of ileum, 1 case of multiple ulcers of jejunum, 1 case of intestinal tuberculosis, 2 cases of vascular malformation of ileum, and 5 cases of no lesions were found. The examination time was 80 to 180 min, with an average of about 100 min. In the examination safety, the site of the endoscope and the time required to reach the endoscope vary depending on the location of the lesion and the patient’s tolerance. During and after the operation, most patients had throat discomfort and mild pain; they improved significantly after giving antispasmodics and other symptomatic treatments; no gastrointestinal bleeding, acute pancreatitis, gastrointestinal perforation or other complications were observed; all patients with endoscopic biopsy did not have symptoms related to gastrointestinal bleeding and perforation. The introduction of double-balloon small intestinal microscopy has revolutionized the diagnosis of small intestinal diseases, and in 2001, YAMADA was the first in the world to report the use of double-balloon propelled small intestinal microscopy, which is a double-balloon propelled small intestinal microscope with an outer tube with an airbag at the tip and an airbag at the tip of the small intestinal microscope. In an experimental study in Japan, the double-balloon trocar mounted on the gastroscope allowed the conventional gastroscope to be inserted 30-50 cm below the varicose ligament, while the double-balloon advancement small bowel microscopy could reach the ileocecal valve, confirming that the double-balloon structure has a long-distance advancement effect. The detection rate of small bowel disease by double-balloon electronic small bowel microscopy is significantly higher than that of other examination methods. In this study, good clinical results were achieved in patients with suspected small bowel lesions who underwent double-balloon e-colonoscopy. Most of the lesions could be detected in the area accessible by endoscopy, and the overall diagnosis rate was 75.0%. The overall diagnostic rate was 75.0%, which was smaller than the diagnostic rate of 83.3% by Zhong Jie et al. In patients with negative small bowel microscopy, the results may be related to the lesion being of non-small bowel origin. Although double balloon small bowel microscopy through the oral cavity can reach the middle and lower ileum under routine circumstances, and some can reach the last ileum, for patients whose endoscope does not reach the ileocecal valve, a small portion of the intestinal segment remains unexamined. In this group of patients, a double-balloon small bowel scope can be used to enter the ileum through the ileocecal valve and continue up to the jejuno-ileal junction, thus completing the examination of the remaining small bowel segment. Therefore, a top-down and bottom-up double balloon small boweloscopy can be performed in different ways and at different times to provide a complete and comprehensive examination of the entire small bowel. In theory, this approach will eliminate any blind spots in the entire small intestine. In this study, one case was embedded in the upper part of jejunum due to capsule endoscopy, and was successfully removed by transoral double-balloon small boweloscopy. In this study, one case was embedded in the upper part of the jejunum due to capsule endoscopy, which was later removed smoothly by oral double balloon small intestine microscopy. At the same time, no significant complications were found in double balloon small intestine microscopy, and no complications were found in one case in this study. Therefore, DBE is the most ideal means of small bowel disease examination. In addition, attention must be paid to the selection of examination timing, and the positive rate of DBE examination decreases after the cessation of gastrointestinal bleeding; double-balloon electronic small bowel microscopy has a high diagnostic rate for gastrointestinal bleeding and mucosal layer lesions, but has less value for the application of submucosal layer and extraintestinal lesions. Other disadvantages such as long examination time and poor patient tolerance also affect the wide application of DBE.