Wandering pancreas

　　The occurrence of ectopic pancreas is related to abnormal embryonic development. At the 6th to 7th week of human embryo development, when the dorsal and ventral pancreatic primordia rotate and fuse with the superior segment of the primitive gut, if one or more pancreatic primordial cells remain in the wall of the primitive gut, due to the longitudinal growth of the primitive gut, the pancreatic primordia can be carried away. The cell tissue produced by the dorsal pancreatic primordia will be carried to the stomach; the ventral pancreatic primordia will be carried to the jejunum, becoming ectopic pancreas. If the pancreatic primordia extend into the gastrointestinal wall, biliary system, omentum, or even spleen, pancreatic tissue will appear in these organs, which is also ectopic pancreas.

　　Ectopic pancreas usually has no clinical symptoms and can be found incidentally during surgery or autopsy.Due to growth in certain special locations or other pathological changes, various complex clinical manifestations may occur. . Common complications include acute pancreatitis, chronic pancreatitis, cysts, adenomas, adenocarcinomas, and so on.

　　Ectopic pancreas usually has no clinical symptoms and can be found incidentally during surgery or autopsy. Due to growth in certain special locations or other pathological changes, the following six clinical manifestations may occur, which some people also call them six types:

　　1. Obstructive type

　　An ectopic pancreas growing in the digestive tract can cause compression or narrowing of the organ, resulting in obstruction symptoms. For example, if located in the antrum of the stomach, it can cause pyloric stenosis; if located in the ampulla of Vater, it can cause biliary obstruction; if located in the intestine, it can cause intestinal obstruction or intussusception, etc.

　　2. Hemorrhagic type

　　Ectopic pancreas is prone to cause gastrointestinal bleeding, the cause may be due to congestion and erosion of the gastrointestinal mucosa around the ectopic pancreas, or erosion of the gastrointestinal mucosal blood vessels leading to gastrointestinal bleeding.

　　3. Ulcer type

　　Ectopic pancreas in the gastrointestinal tract, due to stimulation by digestive juices, can secrete trypsin, digest the gastric and intestinal mucosa to form ulcers; ectopic pancreas located under the mucosa can compress the upper mucosa, causing atrophy, and then ulcers may occur.

　　4. Tumor type

　　An ectopic pancreas, if located in the submucosal layer of the gastrointestinal tract, can cause local bulging of the mucosa; if located in the muscular layer, it can thicken the gastric or intestinal wall, easily misdiagnosed as a gastrointestinal tumor. Occasionally, ectopic pancreatic tissue may develop into an insulinoma, causing hypoglycemia; malignant transformation will then manifest as pancreatic cancer.

　　5. Diverticular type

　　Ectopic pancreatic tissue can be located in congenital diverticula of the gastrointestinal tract, especially common in the Meckel diverticulum, and can cause symptoms such as diverticulitis and hemorrhage.

　　6. Hidden type

　　Since ectopic pancreas is a congenital developmental abnormality, some cases may have no symptoms throughout their lives or be discovered incidentally during surgery or autopsy.

　　When ectopic pancreas causes significant symptoms due to secondary pathological changes, surgical treatment should be performed, such as subtotal gastrectomy, intestinal resection, and diverticulectomy, etc. For smaller lesions, partial resection of the gastric or intestinal wall can be performed and then sutured, but it is strictly forbidden to attempt to simply peel off the ectopic pancreatic tissue from the gastric or intestinal wall. If ectopic pancreas is incidentally found during other surgeries and the patient has no symptoms caused by ectopic pancreas before surgery, it should be removed simultaneously as much as possible under the condition that it does not affect the original surgery and the resection of ectopic pancreas is not difficult. Frozen section should also be performed during the operation. If there is cancer, the resection range should be expanded or radical surgery should be performed.

　　The auxiliary examination methods for this disease are mainly X-ray examination. The characteristic manifestations of X-rays are the key to diagnosis. The typical signs of the lateral X-ray film are: the distance of the displaced vertebra in front is one-third of the posterior diameter of the vertebra, at most not more than one-half. On the plane of the displaced vertebra, the normal articular process cannot be seen.

　　1. The interrelation of joints: The spinous processes located in front and behind the displayed dislocated cervical vertebra deviate from the center and move towards the side of the small joint dislocation. The oblique view can clearly show signs of small joint dislocation or 'locking'.

　　2. Ectopic pancreas usually does not cause any symptoms, and there is currently a lack of specific examination and diagnostic methods. Only a few cases can be diagnosed due to their special location and large size.

　　3. Ectopic pancreas in the prepyloric area can cause pyloric obstruction symptoms (obstructive type). Barium meal examination of the upper gastrointestinal tract can show a filling defect in the prepyloric area, which is smooth, with clear boundaries, and has a wide base and is non-motile. If a small barium spot is seen in the center of the filling defect (similar to an ulcer excavation shadow), it is called a navel sign. In the lateral view, there may be a thin tubular dense shadow extending into the filling defect, called a duct sign. The navel sign and duct sign are characteristic manifestations of ectopic pancreas.

　　5. Ectopic pancreas located in the gallbladder can be seen as a fixed filling defect on cholecystography, with a defect in the gallbladder wall. The shadow of gallstones can move, which can be used for differentiation; however, it is difficult to distinguish from gallbladder polyps.

　　4. Endoscopic examination and biopsy: For ectopic pancreas located in the stomach and duodenum, fiberoptic gastroscopy or choledochoscopy can be performed to understand its location, size, and shape, and to differentiate it from other diseases occurring in the stomach and duodenum. If the opening of the pancreatic duct can be seen, an accurate diagnosis can be made. Biopsy confirming the presence of ectopic pancreatic tissue can definitely diagnose the condition.

　　Diet should be regular and reasonable, mainly high-protein and high-vitamin foods. Choose high-nutrient plant or animal proteins such as milk, eggs, fish, lean meat, and various bean products. Various fresh vegetables and fruits are rich in vitamins and have high nutritional value.

　　When the secondary pathological changes of ectopic pancreas cause obvious symptoms, surgical treatment should be performed. This includes procedures such as subtotal gastrectomy, intestinal resection, and diverticulectomy. For smaller lesions, partial resection of the gastric or intestinal wall can be performed, followed by suture of the gastric wall or intestinal tract. It is forbidden to attempt to simply剥离 the ectopic pancreas tissue from the gastric or intestinal wall.

　　If an ectopic pancreas is found occasionally during other surgeries, and the patient has no symptoms caused by ectopic pancreas before surgery, it should be removed simultaneously as much as possible if it does not affect the original surgery and the resection of the ectopic pancreas is not difficult. Frozen section examination should also be performed during surgery, and if there is cancer, the resection range should be expanded or radical surgery should be performed.

　　The treatment of this disease includes the following key points:

　　1. Traction Reduction

　　Cranial traction and occipito-maxillary band traction are commonly used methods of reduction. During traction, the head and neck are slightly flexed (about 30°), the traction weight is 5 to 6 kg, gradually increased, but not exceeding 10 kg, to avoid or exacerbate spinal cord injury. To facilitate reduction, a sand pad can be placed under the shoulder on the side of dislocation, causing the injured segment to slightly flex, pulling the dislocated articular process apart, and then adjusting the traction direction to realign it. As with bilateral articular process dislocation, throughout the reduction process, close attention should be paid to changes in the overall condition, and bedside radiography should be performed every 10 minutes to grasp the reduction.

　　2. After Reduction

　　Maintain traction with a weight of 1 to 2 kg for 3 to 4 weeks, and then use a cervical-thoracic-cervical plaster cast for fixation for 2 to 3 months. If there is a cervical spinal cord injury, it is not advisable to use plaster fixation, and continuous traction can be maintained for 2 to 3 months until healing.

　　3. Surgical Reduction and Fixation

　　Patients who fail to realign through traction can consider open reduction. The posterior midline incision is used to expose the locked minor articular processes, remove the embedded joint capsule and ligament tissue, and use a periosteal剥离器撬拨使之复位; if difficult, the superior articular process of the lower vertebral body that hinders realignment can be removed, and the traction direction can be adjusted, which is usually realigned.

　　4. If there is spinal cord injury

　　According to the range of compression, laminectomy decompression should be performed. To maintain the stability of the injured segment, a wire ring can be used to tie the spinous process during surgery, and autologous iliac bone grafting can be performed. The commonly used bone grafting method is the 'H' type inter-spinous bone grafting combined with wire fixation. Some people also use inter-articular bone grafting and fixation.