A gallbladder scan is a nuclear scanning test that is done to evaluate gallbladder function. It can detect blockage in the tubes (bile ducts) that lead from the liver to the gallbladder and small intestine (duodenum). See an illustration of the gallbladder and the duodenum.

During a gallbladder scan, a radioactive tracer substance is injected into a vein in the arm. The liver removes the tracer from the bloodstream and adds it to the bile that normally flows through the bile ducts to the gallbladder. The gallbladder then releases the tracer into the beginning of the small intestine. A special camera (gamma) takes pictures of the tracer as it moves through the liver, bile ducts, gallbladder, and small intestine.

Why It Is Done

A gallbladder scan is done to:

• Help determine the cause of pain in the upper right side of the abdomen.
• Evaluate the function of the gallbladder. A gallbladder ultrasound may be done before a gallbladder scan to help detect structural problems in the gallbladder. If the ultrasound is normal, a gallbladder scan often is done to evaluate gallbladder function.
• Help determine the cause of jaundice.
• Detect blockage of the tubes (bile ducts) leading from the liver to the gallbladder and small intestine (duodenum).

How To Prepare

Before your gallbladder scan, tell your doctor if:

• You are or might be pregnant.
• You are breast-feeding. Use formula (discard your breast milk) for 1 to 2 days after the scan until the radioactive tracer has been eliminated from your body.
• Within the past 4 days, you have had an X-ray test using barium contrast material (such as a barium enema) or have taken a medication (such as Pepto-Bismol) that contains bismuth. Barium and bismuth can interfere with test results.

Do not eat or drink for 4 to 12 hours before a gallbladder scan. Your doctor will tell you how long depending on what the test is being done for.

You may be asked to sign a consent form before the test. Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

How It Is Done

A gallbladder scan is usually done by a nuclear medicine technologist. The scan pictures are usually interpreted by a radiologist or nuclear medicine specialist.

You will need to remove any jewelry that might interfere with the scan. You may need to take off all or most of your clothes, depending on which area is being examined (you may be allowed to keep on your underwear if it does not interfere with the test). You will be given a cloth or paper covering to use during the test.