What is an Endoscopic Retrograde Cholangiopancreatography (ERCP)?

Endoscopic Retrograde Cholangiopancreatography (ERCP)

ERCP is primarily a therapeutic procedure that involves advancing an endoscope into the duodenum, cannulating the ampulla, and injecting contrast into the common bile duct (CBD) with fluoroscopic imaging to visualize and treat biliary and pancreatic duct disorders. 1

Procedure Overview

ERCP is typically performed by gastroenterologists or general surgeons in an interventional suite or operating room under general anesthesia. The procedure involves:

• Advancing a side-viewing endoscope through the mouth into the duodenum
• Cannulation of the ampulla of Vater
• Injection of contrast into the bile duct and/or pancreatic duct
• Fluoroscopic imaging to visualize the biliary and pancreatic ductal systems
• Potential therapeutic interventions such as sphincterotomy, stone extraction, stent placement, or tissue sampling 1

Evolution from Diagnostic to Therapeutic Role

ERCP has evolved significantly since its introduction:

• Originally developed as a diagnostic tool in the late 1960s 2
• Currently has an almost exclusively therapeutic role due to advances in non-invasive imaging such as Magnetic Resonance Cholangiopancreatography (MRCP) 1, 3
• At least 75% of ERCP procedures performed today are therapeutic 4

Primary Therapeutic Indications

1. Management of CBD stones:

   • Main indication for ERCP 1
   • 80-95% success rate in clearing stones via balloon sweep of the CBD 1
   • Stones >15mm may require advanced endoscopic techniques 1

2. Biliary stent placement:

   • Standard procedure for managing obstructive jaundice 1

   • 90% success rate for distal CBD strictures 1

3. Tissue sampling:

   • Endoscopically directed brushing or biopsy for suspected malignancies 1
   • Sensitivity varies: 57.1% for pancreatic body/tail neoplasms to 82.4% for pancreatic head neoplasms 1

Complications and Risks

ERCP carries significant risks that must be carefully considered:

• Major complications: 4-5.2% of cases 1, 5

  • Pancreatitis (most common): 3-5% 1
  • Cholangitis: 1-2.8% 1, 5
  • Hemorrhage (especially with sphincterotomy): 1.1-2% 1, 5
  • Perforation: 0.4% 1, 5
  • Mortality: 0.4% 1, 5

• Specific patient risks:

  • Increased risk of suppurative cholangitis in patients with sclerosing cholangitis or biliary stricture 1
  • Higher complication rates in elderly patients, emergency admissions, and those with comorbidities 4

Contraindications and Limitations

ERCP should be avoided or performed with caution in:

• Patients with gastric outlet or duodenal obstruction 5
• Patients with altered surgical anatomy (e.g., Roux-en-Y gastric bypass) 1, 5
• Suspected sclerosing cholangitis or biliary stricture with obstructed system 1, 5
• Primary Sclerosing Cholangitis (PSC): ERCP should only be considered if MRCP plus liver biopsy is equivocal or contraindicated 1

Alternative Diagnostic Methods

Less invasive alternatives to diagnostic ERCP include:

• MRCP: Non-invasive with high sensitivity (86%) and specificity (94%) 5
• Endoscopic Ultrasound (EUS): Excellent for imaging the pancreatic head and distal CBD 1, 5
• Percutaneous Transhepatic Cholangiography (PTC): Alternative for biliary drainage when ERCP fails 5

Technical Advances

Recent innovations in ERCP include:

• Disposable duodenoscopes to eliminate transmissible infections 3
• Cholangioscopy and pancreatoscopy for large bile duct stones and indeterminate strictures 3
• EUS-guided biliary drainage as an alternative when standard ERCP fails 5, 3
• Advanced techniques for patients with surgically altered anatomy 3

Important Clinical Considerations

• The risks of ERCP must be weighed against potential benefits 1
• ERCP should not be performed for purely diagnostic purposes when non-invasive alternatives are available 1, 3, 6
• Technical success rates are high (>90%) in experienced centers 4
• Post-procedure 30-day mortality (1-5%) correlates strongly with age, male sex, emergency admission, and comorbidities 4

ERCP remains a critical procedure in the management of pancreaticobiliary disorders, but its invasive nature and associated risks mandate careful patient selection and performance by experienced endoscopists in appropriate settings.