Makindo Medical Notes

🧪 Endoscopic Retrograde Cholangiopancreatography (ERCP) was once the standard investigation for suspected choledocholithiasis. ⚠️ However, it carries risks such as pancreatitis, perforation, bleeding, and rarely death. ✨ Magnetic Resonance Cholangiopancreatography (MRCP) is now preferred as it is non-invasive, safer, and highly sensitive for biliary and pancreatic pathology.

📖 About MRCP

• MRCP is an advanced MRI technique that provides high-resolution images of the biliary and pancreatic ducts without the need for endoscopy.
• Particularly valuable in detecting gallstones in the common bile duct (choledocholithiasis) and other obstructive pathologies.
• Can also assess the liver, gallbladder, pancreas, and surrounding soft tissues without ionizing radiation, making it safer than CT scans in younger patients.
• Useful in differentiating between benign strictures and malignancy in the biliary system.

⚙️ Techniques

• Uses heavily T2-weighted MRI sequences, which make static or slow-moving fluid (like bile) appear bright and ducts clearly visible.
• Sometimes performed with intravenous (IV) gadolinium contrast to improve visualization of masses or vascular structures (though not always necessary for ductal stones).
• The scan is painless, requires no recovery time, and typically takes 30–45 minutes.
• Patients usually need to fast for a few hours prior to improve bile duct distension.

📌 Indications for MRCP

• 🪨 Choledocholithiasis: To confirm stones in the common bile duct in cases of acute gallstone pancreatitis or obstructive jaundice.
• 🧩 Primary sclerosing cholangitis: To evaluate characteristic bile duct strictures and irregularities.
• 🎯 Biliary & pancreatic malignancy: Non-invasive assessment of strictures, masses, or obstruction.
• 🔥 Unexplained pancreatitis: Identifies structural causes such as pancreatic divisum, strictures, or tumours.
• 🔄 Pre-operative planning: Prior to gallstone surgery or biliary interventions.

🚫 Contraindications

• Pregnancy – generally avoided in the first trimester unless benefits outweigh risks.
• ❌ Gadolinium contrast is avoided in pregnancy unless essential.
• Absolute contraindications: patients with non-MRI-compatible pacemakers, ICDs, cochlear implants, metallic foreign bodies, or ferromagnetic aneurysm clips.
• Claustrophobia may limit use, though sedation can sometimes help.

🌟 Clinical Pearls

🔑 MRCP is purely diagnostic – it cannot treat stones. If a stone is confirmed, patients usually require therapeutic ERCP for stone removal. Think of MRCP as the “safe scout” 🕵️ before the “treatment mission” 🚑 with ERCP.

📚 References

• Radiopaedia: MRCP
• British Society of Gastroenterology Guidelines: Investigation of Biliary Disease (2021)