Endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance cholangiopancreatography (MRCP) are medical tests. They’re used to diagnose problems in the bile and pancreatic ducts, such as:

ERCP involves an endoscope and X-ray to create images of your ducts. It’s a gold-standard method for diagnosing bile and pancreatic issues. However, it’s invasive and associated with various complications.

MRCP is a type of magnetic resonance imaging (MRI) technique. It uses magnets and radio waves to produce images of the ducts. The procedure is noninvasive and doesn’t use radiation, unlike ERCP.

Read on to learn about the differences between ERCP and MRCP.

Before you get either procedure, your doctor will consider any allergies or medical conditions you have.

These factors might increase your risk of complications related to contrast dye, which is used to produce better images. It’s used in ERCP and some MRCP tests.

Depending on your risk factors, your doctor might take extra precautions when planning your procedure.

Preparation also depends on the test.

ERCP preparation

ERCP involves sedatives. Therefore, here’s what preparation will involve:

  • You might need to stop taking your medications for a short time if they interact with sedatives. You may also need to temporarily stop taking medications that control blood clotting.
  • Ask a trusted friend or relative to help you get home. You’ll be asked to avoid driving for 24 hours after the procedure.
  • Avoid eating, drinking, smoking, or chewing gum 8 hours before ERCP. This will let your doctor view your intestinal tract properly.

MRCP preparation

Since MRCP is less invasive, the preparation process is less strict. It may involve the following:

  • Wear comfortable clothing.
  • Take off all your jewelry.
  • Let your doctor know if you have an implanted device.
  • You might need to avoid eating or drinking for a few hours before the procedure.

Here’s how ERCP and MRCP compare.


ERCP uses an endoscope, which is a long tube with a tiny camera at the end, and a catheter. Both tools are inserted into your small intestine. ERCP also involves X-ray, which uses radiation to create images of the ducts.

MRCP involves an MRI machine. It uses magnets and radio waves to take images.


Both techniques are used to detect pancreatic and bile duct problems. They produce similar images that can be used for diagnosis.

ERCP also allows your doctor to complete certain treatments, such as:

If you’re unable to get ERCP, MRCP can be used as a substitute. MRCP can also determine if you need ERCP as a pre-surgery procedure.


Both tests may be done at a hospital or outpatient center. You can also receive either test as part of a hospital stay.


During both procedures, you’ll be lying down on a table.

ERCP takes 1 to 2 hours. It generally involves the following:

  1. Your doctor will give you an intravenous (IV) line of sedatives to help you relax.
  2. They will also give you a local or general anesthetic.
  3. Your doctor will insert an endoscope into your mouth until it reaches your small intestine.
  4. They’ll locate the ducts and insert a catheter into the endoscope until it reaches the ducts.
  5. Your doctor will inject a contrast dye into the ducts and take an X-ray.

The process of getting MRCP takes 45 to 60 minutes. It involves:

  1. You’ll lie flat on your back on a table, which will slide into the MRI machine.
  2. If you’re also getting a standard MRI, a contrast dye will be injected into your arm.
  3. You’ll be asked to stay still during the entire test. You’ll also be asked to hold your breath for 12 to 18 seconds several times.
  4. The MRI machine will take multiple images of your ducts.

After ERCP, you’ll need to wait for the sedative or anesthesia to wear off. You’ll likely need to stay at the hospital or outpatient center for 1 or 2 hours.

You may also experience the following after ERCP:

  • bloating
  • nausea
  • sore throat

It’s recommended to rest when you’re back home. You can return to your usual diet when your sore throat goes away.

MRCP requires little to no recovery. You can go home after the procedure. If you took a sedative, you’ll need a ride home.

Since ERCP is invasive, the procedure is associated with more risks than MRCP. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), complications occur in 5 to 10 percent of ERCP tests.

Potential ERCP complications include:

  • pancreatitis, which is the most common complication
  • infection of the gallbladder or bile ducts
  • gastrointestinal bleeding
  • puncture of ducts or small intestine
  • atypical reaction to the sedative or dye
  • tissue damage from the X-ray

MRCP is noninvasive, so there are fewer risks. They include:

  • kidney scarring from the dye
  • allergic reaction to the dye
  • issues relating to implanted devices

If you’re allergic to iodine, it’s best to avoid ERCP. That’s because the contrast dye used in ERCP contains iodine. In this case, MRCP is the safer choice.

But if you need another treatment, like a stone removal, ERCP is the better choice. MRCP won’t allow your doctor to complete other treatments.

A hepatobiliary iminodiacetic acid (HIDA) scan is used to take images of the bile ducts, gallbladder, liver, and small intestine. It involves a radioactive tracer that’s injected into your vein.

It’s also called:

  • hepatobiliary scan
  • cholescintigraphy
  • hepatobiliary scintigraphy

A HIDA scan might diagnose a condition that can be treated with ERCP. It might also be used after MRCP to confirm the results.

The cost of ERCP and MRCP can vary greatly. It depends on many factors, like your insurance provider and where you live.

According to MDsave.com, the average cost for ERCP is $11,234.

The average cost for MRCP is $4,656, according to a 2015 article.

Both ERCP and MRCP are only used to diagnose medical conditions. If you have health insurance, this means your provider should cover some or all of the costs.

ERCP and MRCP are used to diagnose problems with the bile and pancreatic ducts. ERCP is more invasive, but it can be used as a treatment for certain conditions. MRCP is noninvasive and is ideal if you’re unable to get ERCP.

Your doctor can determine which test is best for you. They’ll consider factors like your medical history and symptoms. In some cases, they might use MRCP to determine if you need ERCP.