内視鏡的処置 V: ERCP

Endoscopic Retrograde Cholangiopancreatography (ERCP) is a therapeutic procedure that integrates endoscopy with fluoroscopy to examine and treat biliary and pancreatic ductal conditions. A side-viewing duodenoscope is inserted through the mouth, esophagus, and stomach into the duodenum. Contrast material is injected into the ducts, and real-time X-ray imaging captures the contrast flow, enabling visualization of abnormalities like gallstones and strictures.

Patient preparation includes explaining the procedure and obtaining informed consent. Patients must fast for at least eight hours to minimize aspiration risk and clear the stomach. Medications like NSAIDs are withheld, and pre-procedure drugs such as glucagon or anticholinergic agents are administered to reduce duodenal peristalsis and facilitate cannulation. Sedatives may also be given to relax the patient and minimize discomfort.

Once the duodenoscope reaches the duodenum, a cannula or catheter is carefully guided through the duodenoscope into the major duodenal papilla, the opening where bile and pancreatic ducts enter the duodenum. This precise positioning allows contrast material to be injected into the ducts for visualization. Proper cannulation is essential for successful imaging and any therapeutic interventions.

Fluoroscopy captures real-time X-ray images that allow physicians to observe contrast material flow through the biliary and pancreatic ducts. This imaging can identify abnormalities including gallstones, strictures, bile leaks, and tumors. The combination of contrast injection and fluoroscopy enables comprehensive visualization of ductal structures and pathology.

ERCP is both diagnostic and therapeutic, allowing interventions such as sphincterotomy, gallstone removal, and stent placement to relieve strictures and keep ducts open. Biopsy or brush cytology can also be performed to diagnose malignancies and other conditions. These therapeutic capabilities enable treatment of identified problems in a single session.

After ERCP, patients are closely observed for respiratory or central nervous system depression from sedatives. Vital signs are monitored and the return of the gag reflex is checked. Healthcare providers watch for signs of perforation such as abdominal pain, excess gas, and fever. Patients typically rest for the remainder of the day and can resume regular activities and diet the next day.

Unlike standard endoscopic procedures, ERCP uniquely combines endoscopy with fluoroscopy to visualize and treat biliary and pancreatic duct conditions. While endoscopic procedures like esophagogastroduodenoscopy examine the upper GI tract, ERCP specifically targets the ductal systems using real-time X-ray imaging. This dual-imaging approach enables both diagnosis and therapeutic intervention in one procedure.