EST was pioneered by Karwai in 1974 and applied to clinical treatment of common bile duct stones. After more than 30 years of application and development, it has now become a safer and more mature technique. Compared with traditional open surgery, it has the advantages of less pain, faster recovery, and is not limited by factors such as adhesions around the bile ducts after multiple surgeries and old age and frailty. The success rate of ERCP is 92%, while the success rate of EST can reach 98%. Therefore, EST is widely used for perioperative stone extraction in patients with gallbladder stones combined with common bile duct stones, especially for patients with acute pancreatitis, common bile duct stones that cannot tolerate larger surgery and residual or recurrent stones in the common bile duct after LC surgery, but The complication rate is around 10%, and due to the size of the opening of the extraction basket, it is often not possible to remove all the stones in patients with huge common bile duct stones and multiple stones. long-term follow-up by Costamagna et al. showed that the recurrence rate of biliary disease after EST of common bile duct stones was 12%. the incidence of recent complications related to EST was 7%, including bleeding (1%-5%), acute cholangitis ( The rate of long-term complications is 12%, including recurrence of common bile duct stones (9.7%-11.9%), cholangitis (9.7%-11.9%), papillary stenosis (0.5%-6.8%), cholecystitis (5.8%-6%), and possible malignancy. So far, the factors of cholangitis and recurrence of biliary stones after EST are still unclear and may be related to the disruption of the structure and function of the sphincter muscle by EST EST is considered to be a simple and easy way to manage biliary stones and duodenal papillary stenosis, and has been widely used in clinical practice. In patients with concomitant jaundice, septic cholangitis and other high-risk factors, EST is even widely recognized as the preferred surgical approach. ANSELMI et al. treated patients with bile duct stones complicated by acute cholangitis with endoscopic drainage or open surgery and found that endoscopic treatment had significant advantages over conventional surgery and could significantly reduce the complication rate and mortality. However, EST as an invasive minimally invasive treatment can still lead to many postoperative complications. We can broadly classify postoperative complications into early complications (<3 months) and long-term complications (≥3 months) according to the time of their appearance. early complications of EST often appear within 24 h after surgery, and common symptoms include bleeding, perforation, acute biliary ductitis, acute pancreatitis, etc. The incidence is roughly 6.3%-11%, and the causes are mainly related to the operator's operating technique. postoperative complications of EST Long-term complications mainly include retrograde cholangitis, pancreatitis, recurrence of common bile duct stones, postoperative biliary end stenosis, and biliary malignancy. The literature reports that the incidence of long-term complications after EST surgery ranges from 5.8% to 18% at an average follow-up of 8 years, and from 5.8% to 24% at an average follow-up of more than 10 years. Because it is difficult to observe the long-term prognosis of patients undergoing EST surgery, there is a lack of relevant literature reports. Preoperative patient jaundice, acute cholangitis, acute pancreatitis, duodenal diverticulum, and the type of bile duct stones have been studied as risk factors for the emergence of long-term complications after EST, but the findings are not uniform. In fact, the underlying causes of long-term complications are biliary infection due to loss of duodenal sphincter function and papillary stenosis due to scar contracture at the papillotomy site. The duodenal sphincter is a critical barrier between the bile duct and the duodenal lumen and functions to resist intestinal fluid reflux and maintain a normal bile-intestinal pressure gradient. Once the sphincter of Oddis is cut, the pressure gradient in the common bile duct decreases and the contents of the intestinal lumen flow back into the bile duct, thus causing retrograde bacterial infection and subsequently increasing the risk of stone recurrence.MANDRYKA et al. evaluated the effect of EST surgery on bacterial colonization, chronic infection of the common bile duct, and recurrence of bile duct stones and found that all post-EST patients had bacterial colonization in the bile duct The majority were Gram-negative bacteria, and all were multibacterial infections, with the most common bacterial cultures being Escherichia coli and Enterococcus. Moreover, the width of the common bile duct, the number of bacterial cultures and the virulence of the bacteria increased with the prolongation of the post-EST period. Because biliary tract infection is inevitable after EST, many believe that preservation of the gallbladder after EST is one of the risk factors for the emergence of long-term complications. This is because when bile duct inflammation spreads to the gallbladder it can lead to cholecystitis and gallbladder stone formation; gallbladder stones falling into the common bile duct can lead to recurrence of bile duct stones. However, LAI et al. found that there was no significant effect of gallbladder removal or not on the recurrence of common bile duct stones in patients after EST, so prophylactic removal of the gallbladder was considered unnecessary and cholecystectomy should be performed only when complications do arise. In our group, 31 of 103 cases had gallbladder present at the time of EST, 19 of which had no gallbladder lesions and 13 were accompanied by gallbladder stones. In the 13 patients with gallbladder stones, laparoscopic cholecystectomy was performed immediately after EST, and none of them had any postoperative complications. In contrast, 19 patients with normal gallbladder underwent EST only, and 3 cases developed complications after surgery, 1 case was recurrence of bile duct stones; 2 cases developed gallbladder stones, which appeared at 16, 18 and 24 months after surgery, respectively, and their complication rate was 15.8%. However, there was no significant difference in the statistical analysis between the two groups (Fisher's exact probability method, P=0.253). Therefore, it is reasonable to believe that the presence of the gallbladder does not increase the recurrence of bile duct stones, but rather ensures the physiological characteristics of bile secretion in patients and reduces postoperative digestive discomfort; at the same time, the contraction of the gallbladder caused by food stimulation and the large amount of bile secretion can also play a role in bile duct contouring, thus effectively preventing the formation of stones. Complications can also occur when scar contracture at the papillotomy site causes the papilla to narrow again and the bile excretion channel is obstructed. Since papillotomy is the direct cause of scar growth, appropriate incision method and incision size have been considered as key measures to prevent the emergence of postoperative complications in EST. In patients with duodenal insufficiency (disorder), a complete incision of the sphincter of Oddis is generally required to prevent cholestasis and stone formation, whereas in patients with papillary stenosis, a small to medium incision of the papilla can be performed. The larger the incision, the greater the damage to the sphincter of Oddis and the greater the chance of complications; at the same time, the larger the incision, the more likely it is to produce reflux of intestinal contents into the bile duct, causing cholangitis, pancreatitis and even bile duct cancer. Such an incision can significantly reduce the incidence of short-term complications of EST surgery and prevent the occurrence of bile duct infection. The size of papillotomy performed in our center ranged from 0.5 to 1.5 cm, with an average of (0.9456±0.169) cm. We believe that the length of the incision should be just enough to pull out the stone, and for oversized stones the mesh basket can be pulled and crushed first. The incision usually does not exceed 1.5 cm, and the farthest incision is about 2-3 mm from the junction with the intestinal wall, with good postoperative results. In addition, the incidence of distant complications varies with the same incision length performed in patients with different etiologies. This explains why patients with simple bile duct stones have a lower incidence of acute pancreatitis and papillary (re)stricture after EST than patients with duodenal papillary stenosis. This may be due to the fact that: (1) most patients with papillary stenosis have combined sphincter malfunction, and conventional small to medium sized incision of the papilla does not completely relieve the symptoms of poor bile drainage; (2) patients with papillary stenosis are more likely to develop massive local fibrous tissue hyperplasia and scar contracture after incision, leading to re-stenosis of the papilla; (3) patients with papillary stenosis have more difficulty in accessing the papilla with a needle knife, and repeated electrical incision and probing lead to severe local mucosal injury, which increases scar tissue generation. However, our group study of patients with different etiologies found that the complication rate of 8 patients with duodenal papillary stenosis, one of whom had a recurrence of stones 8 months after surgery, was 12.5%, which was not significantly different from the complication rate of 12.6% in our group of patients with simple bile duct stones (P=0.9). This is different from the results reported in the literature, and the reason for this may be related to the small sample size. In conclusion, the reliability of the theory that patients' preoperative jaundice may be a risk factor influencing the emergence of postoperative complications in EST needs to be further demonstrated. The underlying causes for the emergence of distant complications are disruption of papillary sphincter function, poor bile drainage; retrograde infection of duodenal bacteria and repeated irritation of the bile duct by long-term bile duct inflammation. From the return of cases after EST in our center, the overall surgical efficacy is relatively satisfactory, and EST can be used as the treatment of choice for biliary obstruction due to different causes.