Pancreatic trauma accounts for about 2% of abdominal trauma, of which 5% is caused by blunt trauma and 8% by sharp trauma. The clinical presentation of pancreatic trauma is insidious, early diagnosis is difficult, and the morbidity and mortality rates and complication rates are extremely high, reaching 30% and 45%, respectively [1]. Therefore, it is important to find timely and effective early diagnosis methods and make correct treatment decisions to improve patient prognosis. Preoperative diagnosis of pancreatic trauma Simple pancreatic injury is difficult to diagnose at an early stage because there are no obvious symptoms and signs. The sensitivity and specificity of blood and urine amylase and ultrasound are poor. CT can make the diagnosis based on pancreatic rupture, peripancreatic fluid retention and prerenal fascial hypertrophy, but there is a certain rate of missing the diagnosis for simple pancreatic duct system injury. The integrity of the main pancreatic duct is the most important factor affecting the prognosis of patients with pancreatic trauma [2]. Endoscopic retrograde cholangiopancreatography (ERCP), as a minimally invasive interventional technique, has become the gold standard for the diagnosis of pancreatic trauma and plays an important role in its treatment because of its significant advantages in many aspects such as pancreatic duct visualization, pancreatic duct stent placement and drainage. For patients with pancreatic trauma, the advantages of ERCP are: (1) it can show the rupture of the pancreatic duct early, precisely and visually, and avoid the leakage caused by CT and other imaging examinations to the maximum extent; (2) it can be used preoperatively, intraoperatively and postoperatively with good dynamics; and (3) the results of visualization can guide the implementation of treatment decisions. Takishima [3], a Japanese scholar, established injury grading criteria based on pancreatic ductal visualization (ERP) results through a retrospective case study (Table 1). Conservative treatment is feasible for patients with grades 1 and 2A, while patients with injury up to grade 2B require emergency drainage surgery; patients with grade 3 have involved main pancreatic duct injury, and distal pancreatic resection, pancreaticoduodenectomy, or pancreaticojejunostomy with Roux-en-Y anastomosis are selected depending on whether the injury site is in the tail or head of the pancreatic body, respectively. This grading method can guide clinicians to complete the localization and diagnosis of pancreatic injury in the shortest time and develop further treatment measures to prevent complications and reduce the morbidity and mortality rate. Despite these advantages, ERCP has certain drawbacks, including: (1) the complication rate of ERCP is high under emergency conditions, up to 3-5%, mainly pancreatitis; (2) it is difficult to intubate patients with post-traumatic duodenal mucosal edema, and about 10% of patients have unsuccessful intubation or inadequate visualization; (3) the visualization results of very few patients are inconsistent with the results of abdominal exploration. ④An experienced endoscopist is required to perform the procedure. Compared with ERCP, MRCP can also show the injury of the main pancreatic duct and its branches, and has the advantage of being non-invasive. It is suitable for patients with anatomical changes that make ERCP intubation difficult, such as pyloric hollowing and duodenal diverticulosis, and can also show whether there are joint injuries in other abdominal organs, but it cannot perform therapeutic operations. In recent years, new techniques such as contrast-enhanced ultrasound (CEUS) have also been used for the diagnosis of pancreatic injury, but their sensitivity and specificity remain to be seen. Table 1 ERP grading criteria for pancreatic injury Injury grading Contrast-enhanced ultrasound results Treatment Grade Normal pancreatic duct Non-operative treatment Grade Branch pancreatic duct injury Pancreatic leak located in the pancreatic parenchyma Non-operative treatment Pancreatic leak extending into the retroperitoneal cavity Dissection and drainage required Grade Main pancreatic duct injury Main pancreatic duct injury located in the tail of the pancreatic body Caudal pancreatic body resection Main pancreatic duct injury located in the head of the pancreas Pancreaticoduodenectomy/pancreatic jejunostomy Roux-en-Y anastomosis Y anastomosis Surgical treatment of pancreatic trauma Surgical treatment Except for patients with no obvious signs of peritonitis, no combined other organ injuries, hemodynamically stable and no main pancreatic duct rupture detected in preoperative diagnosis, conservative treatment should be considered, and all patients should be actively treated surgically. According to the results of the dissection, different surgical methods should be selected in combination with the five levels of pancreatic injury classification of the American Association for the Surgery of Trauma (AAST). For grade I and II patients, i.e., those with only contusions or lacerations but no involvement of the pancreatic duct and no tissue defects can undergo drainage surgery only. For grade III distal pancreatic injury involving the pancreatic duct on the left side of the superior mesenteric vessels, distal pancreatic resection should be performed, the proximal main pancreatic duct section should be ligated with nonabsorbable sutures, and the pancreatic section should be closed with double sutures and covered with large omentum, while for grade III pancreatic injury on the right side of the superior mesenteric vessels, the proximal end should be closed and the distal end should be closed with a Roux-en-Y anastomosis to the jejunum. In patients with grade IV and V injuries, the head of the pancreas is involved, and surgery should be performed depending on whether there is a combined duodenal and jugular injury. In patients without combined injuries, resection of the head of the pancreas with preservation of the duodenum is feasible. In cases of complex pancreaticoduodenal injury, diverticulization of the duodenum or pyloric exclusion surgery may be an option. Duodenal diverticulization surgery leaves the duodenum open, with only pancreatic fluid and a small amount of bile passing through, forming a low-pressure diverticulum that facilitates healing of the damaged duodenum. Pyloric exclusion surgery repairs the duodenal incision, incises the gastric sinus, blocks the pylorus, and anastomoses the sinus incision with the jejunum. Since this procedure is relatively easy to perform and takes a short time, there is a trend to gradually replace the former in recent years. The main complication of PD is pancreaticoduodenectomy (PD), with an incidence of 50% and a postoperative mortality rate of 30%-60%. Some scholars have tried to use single-layer anastomosis technique and bundled pancreatic-enteric anastomosis technique to reduce the incidence of anastomotic fistula, and certain results have been achieved. The therapeutic value of endoscopy in pancreatic trauma The therapeutic value of endoscopy in early pancreatic trauma With the development of endoscopic technology and medical interventional materials, case reports of successful treatment of pancreatic trauma by ERCP have become common. The core concept is to restore the integrity of the pancreatic duct, reduce or block pancreatic leakage, create opportunities for further treatment, and reduce treatment risks. Transpapillary stenting (TPS) or indwelling nasopancreatic drain (NPD) is the main method of ERCP for pancreatic trauma. The stent or drain supports and connects the ruptured pancreatic duct to stop the pancreatic leak, thereby accelerating the healing of the rupture and reducing the internal pressure in the pancreatic duct system.Kim et al [4] reported three cases of ruptured main pancreatic duct with pancreatic leak confined to the parenchyma treated with TPS, all of which were treated within 24-96 hours after the injury and the patients recovered well.Canty et al treated two pediatric cases with the same approach The stent was successfully removed 11 days after surgery. In patients with early single pancreatic trauma who are hemodynamically stable and have a partially ruptured pancreatic duct that can still be connected by stenting, timely TPS or NPD can sometimes prevent a high-risk pancreatectomy in an emergency setting. We have treated five patients with early pancreatic trauma with this technique and all recovered well. In such patients, we prophylactically place biliary stents along with pancreatic duct stents due to the possibility of papilledema and secondary biliary obstruction and liver function impairment due to pancreatic injury. and the main complications of NPD include: ① secondary pancreatic duct stenosis after stent removal, the cause of which may be caused by the trauma itself or the stent and has not been clarified. In recent years, some scholars have used a small diameter (3-Fr or 4-Fr) stent without an unflanged inner end to replace conventional stents for TPS. (ii) stent blockage: some studies found that the blockage rate is proportional to the time of stent placement; (iii) stent displacement; (iv) duodenal erosion and infection. In patients with early injury, TPS and NPD have a better clinical outcome for those who successfully bridge the two ends of the pancreatic duct dissection. At present, the safety and efficacy of this technique are yet to be further evaluated due to the small number of relevant case reports and the lack of conclusions from large sample of randomized controlled clinical studies. Role of endoscopy in the treatment of delayed complications of pancreatic trauma Delayed complications of pancreatic trauma mainly include chronic pancreatic leakage and pancreatic pseudocysts. The latter of these is a restricted accumulation of pancreatic enzyme-rich fluid surrounded by a non-epithelial cyst wall. Persistent pancreatic pseudocysts can lead to serious complications such as infection, abscess formation, bleeding due to erosion of peripheral blood vessels, rupture into adjacent organs, and compression of adjacent organs, which require timely drainage. Traditional drainage procedures include external drainage, internal drainage and partial pancreatectomy. At present, the most commonly used conventional surgical procedure is Roux-en-Y anastomosis of cystic jejunum, which is an internal drainage procedure and is suitable for cysts in various locations, especially for cysts in the tail of pancreas. The most common complication in the immediate postoperative period is mainly gastrointestinal bleeding, which is also the main cause of death in patients after surgery. In cases where the stomach or duodenum has a common wall with the pseudocyst, pancreatic pseudocysts can be drained by transgastric puncture under ultrasound or CT guidance, mainly including cyst gastric drainage and cyst duodenostomy drainage, with a higher success rate and a significantly lower overall complication rate than traditional open surgery, mainly for gastrointestinal penetration and bleeding. In recent years, ERCP has also made progress in the treatment of chronic post-traumatic pancreatic leakage and pancreatic pseudocysts.Lin [5] et al. reported the successful treatment of pseudocysts formed after routine AAST class IV pancreatic trauma by endoscopic transpapillary drainage (ETD). Satisfactory results of transnasal pancreatic drainage (NPD) have also been reported in the literature. However, similar to this technique for early trauma, the incidence of secondary main pancreatic duct stenosis is high. In conclusion, traditional surgery is still the most important method for treating pancreatic trauma, but new techniques including endoscopy have shown their advantages in diagnostic sensitivity, precision and minimally invasive treatment, and have broad application prospects. For patients with pancreatic trauma, timely and accurate diagnosis and risk assessment and selection of appropriate treatment methods are necessary to minimize the incidence of complications and achieve the best outcome.