The duodenal periampullary diverticulum, also known as the duodenal peripapillary diverticulum, is a congenital disease characterized by a bag-like structure composed of the duodenal mucosa, submucosa and muscularis mucosae. A herniation-shaped structure in which the muscular layer protrudes out of the intestinal lumen, usually within 2-3 cm of the nipple. In the past, the diagnosis of PAD mainly relied on the upper gastrointestinal barium meal and intraoperative findings, and the diagnosis rate was <1%. In recent years, with the popularization and promotion of ERCP, the diagnosis rate of PAD has increased significantly. In recent years, the detection rate of PAD in ERCP patients is 9%-32%, and it is more common in the elderly population, and it is rare in people less than 40 years old, and its incidence increases with age. PAD can affect common bile duct bile excretion and is an important factor affecting the occurrence of common bile duct stones.

2. Impacted nipple stones affect ERCP surgery

Papillary stone incarceration is an emergency in hepatobiliary surgery, which can lead to complete obstruction of the outflow tract of the bile and pancreatic ducts, obstruction of bile and pancreatic juice discharge, and increased pressure in the bile and pancreatic ducts, resulting in acute cholangitis, acute pancreatitis, and even acute Serious complications such as suppurative obstructive cholangitis and severe acute pancreatitis. Before the advent of therapeutic endoscopic techniques, the calculi in the nipple were removed by surgical means, but surgery was performed on severe patients such as acute suppurative obstructive cholangitis, and the mortality and complication rates of surgical treatment were high. For patients with poor general condition who cannot tolerate long-term surgery, T-tube biliary drainage should be performed first. After the condition is stable, choledochoscopy can be used to remove stones through the T-tube sinus. Sometimes repeated stone removal or reoperation is required, or even papilloplasty. For incarcerated stones in the nipple, even if choledochoscopy is used in surgical ERCP, it is still very difficult to successfully remove the stones. In addition, long-term stone impaction compression will cause chronic inflammation and fibrosis of the nipple and adjacent bile ducts and pancreatic ducts, resulting in nipple stenosis, making ERCP intubation difficult.

3. Duodenal papillary stenosis affects ERCP surgery

The causes of papillary sphincter stenosis are divided into benign etiology and malignant etiology, and a small number of primary papillary stenosis have unknown causes. Benign strictures of the duodenal papilla are classified into two types: muscular stenosis and muscular dyskinesia. About 60% of benign stenoses are due to structural abnormalities of the sphincter. Pathology shows inflammation, muscle hypertrophy, fibrosis, or endometriosis. The remaining 40% have no structural abnormalities, which are considered to be caused by damage to the important nerves that innervate the sphincter. , but the etiology of most patients is still unknown. Benign causes of duodenal papillary stenosis have been proven to include iatrogenic injury, acute and chronic pancreatitis, choledocholithiasis, primary sclerosing cholangitis, associated sclerosing cholangitis, bile duct anastomotic stricture, bile duct After surgery, incision scar stenosis, recurrent suppurative cholangitis, syndrome, acquired immunodeficiency syndrome biliary tract disease, sphincter dysfunction, etc., lead to bile duct fibrous tissue hyperplasia, scar contracture, and secondary stenosis. Among them, iatrogenic injury is the most common.

In the case of combined nipple stenosis, methods such as double guide wire method and straightening of the mirror body method can be tried. If there is still no successful intubation, nipple pre-incision can be considered. However, it should be noted that in principle, needle-shaped knife pre-incision is not recommended for diagnostic ERCP surgery. Before pre-incision, the patient's tolerance must be carefully considered, the risk of complications such as perforation, bleeding, and pancreatitis, and the ability to withstand remedial measures such as surgery, etc., before deciding whether to perform pre-incision. In particular, caution should be exercised in patients with insignificant dilation of the common bile duct. The prerequisite for successful intubation is that the bile duct has continuity and the guide wire can pass through the stenosis.