HIDA Scan

What is a HIDA scan?

A HIDA scan is a test that can be done to see how well your gallbladder is working.

The gallbladder is a small sac that lies under the liver. It stores bile. Small tubes called bile ducts drain bile from the liver into the gallbladder and then into the small intestine. The bile helps you digest fats in the food you eat.

When you have the test, a tiny amount of radioactive chemical is injected into your vein. The chemical is called a tracer. The tracer attaches to the bile in your liver and gallbladder. With the tracer, pictures can be taken of your liver, gallbladder, and bile ducts to see how well the bile is flowing from the liver, through the gallbladder, and into the small intestine.

The full name for this test is hepatobiliary iminodiacetic acid scan. It is also called cholescintigraphy or hepatobiliary scan.

When is it used?

A HIDA scan is done to diagnose problems with the gallbladder. It may be done if you are having pain in the upper right side of your belly that your healthcare provider thinks may be caused by your gallbladder.

A gallbladder ultrasound may be done first. If the ultrasound is normal and doesn’t show any problems, the next step is a HIDA scan. The HIDA scan can help your healthcare provider diagnose:

• gallstones that didn’t show up on ultrasound
• blockage of bile ducts
• bile leakage
• problems with the way the bile ducts were formed before you were born.

The scan may be done as part of other tests.

How do I prepare for it?

Usually you will need to fast for several hours before your scan. Ask your healthcare provider for the specific instructions for your test. In most cases you’ll be able to drink clear liquids before the test.

Discuss all of your medicines with your provider. You may need to wait to take some of your medicines until after your scan.

Before your scan it is also important to tell your provider if:

• There is any possibility you are pregnant. Most of the time you should not have the scan if you are pregnant.
• You are breastfeeding. You will need to discard your milk for 1 to 2 days after the scan.
• You have had any recent medical procedures or medicines with barium or bismuth—for example, you have had a barium enema or you have been taking Pepto-Bismol.

When you go to have your scan, you should wear comfortable, loose-fitting clothes and leave your jewelry at home.

What happens during the scan?

The technician will inject the radioactive tracer into your arm. You will lie on your back on the table. A large camera will take pictures of the radioactive chemical as it passes through your liver system for about an hour. You may need to stay very still while the pictures are being taken. In some cases, you will need to return to the X-ray department later in the day or the next day for more scanning.

What happens after the scan?

Usually you’re able to go back to your usual schedule after the scan. The radioactive tracer will leave your body over the next several hours mainly in your urine and stools. The tracer does not cause you to be a danger to others. The day you have the scan it’s recommended that you flush twice after using the toilet and be especially sure to wash your hands well. You may be able to flush the tracer out faster by drinking lots of water.

What are the risks of the scan?

The scan has almost no risk. Allergic reactions to the tracer are very rare.

What are the benefits of the scan?

The scan allows many gallbladder and bile duct problems to be diagnosed without invasive procedures like surgery. It is usually quite painless and involves very little preparation or unwanted side effects.

When should I call my healthcare provider?

Call your provider right away if:

• You start having a rash within a few hours of the scan.
• You have a bruise that is getting bigger at the place where the tracer was injected.
• The symptoms for which you had the scan are getting worse, like fever, abdominal pain, or vomiting.

You should call during office hours to:

• Make your follow-up appointment.
• Get the results of the scan.