A gallbladder radionuclide scan is an imaging test that uses radiation to detect:
- bile fluid leakage
- blockage in your gallbladder
The procedure uses radioactive “tracers” injected into your bloodstream that are viewed under specialized imaging equipment.
The gallbladder is a small organ underneath your liver that stores bile.
The gallbladder radionuclide scan is also called hepatobiliary imaging, or hepatobiliary iminodiacetic acid scan (HIDA).
A gallbladder radionuclide scan is done to help detect potential problems with your gallbladder or ducts near the gallbladder. Problems may include:
- bile duct blockage
- cholecystitis, or gallbladder inflammation
- bile leakage
- birth defects
In the case of detecting birth defects, the scan is performed early in life on newborns or young children.
The procedure can also be used to test your gallbladder ejection fraction, which is the percentage of total bile that gets produced during a certain period of time. The rate at which your gallbladder releases bile can also be determined by this procedure.
There’s a risk of exposure to radiation with this test, as the scan uses small amounts of radioactive tracers. However, this test has been used for over 50 years. There are no known long-term side effects from such low doses of radiation.
There’s a rare chance of an allergic reaction, which is typically mild.
Pregnant women or women who believe they could be pregnant should not undergo the test.
While the levels of radiation the tracers emit are considered safe for adults, they’re unsafe for developing fetuses. You should tell your doctor if there’s a chance that you’re pregnant before agreeing to have the scan.
Your doctor will give you complete instructions on how to prepare for your gallbladder radionuclide scan. These instructions may include fasting for four hours before the test.
At appointments before the scan, your doctor will perform a physical examination and request your complete medical history. Tell your doctor about any allergies you have and any medications you’re taking, including over-the-counter medications or nutritional supplements.
Let your doctor know if you have problems lying still for an extended period, as the test can take up to 90 minutes.
The procedure is typically done on an outpatient basis. You can go home when your gallbladder radionuclide scan is complete.
The machine used to complete the scan looks like a large metal donut with a table coming out of it.
You’ll begin by removing all jewelry. You may be required to change into a hospital gown. You’ll then lie flat on a scanning table.
A trained specialist will insert an intravenous (IV) needle into your arm and deliver radiotracers. The tracers will:
- travel through your bloodstream
- work their way into your gallbladder
- move through the bile ducts attached to it
When the medication (radionuclide) has properly absorbed into your body, the scan portion of the test begins. The technician will slide you into the machine feet-first. Your head will remain outside of the machine.
You’ll be instructed to hold still while the scan is in progress. This may be uncomfortable, but it helps the machine to achieve clear images.
Your healthcare provider will be watching the scan on a monitor as the tracers move through your body. When the tracers reach your small intestine, the scan is over.
After the scan, you’ll be instructed to drink plenty of water so the excess radioactive tracers can be flushed from your body.
If your doctor requested a stat reading, you may get your test results within hours. Or, your doctor may want to review them with you later.
The images from the scan are in black and white. Concentrated dark areas signify the concentration of the radioactive tracers.
If no tracers are found on the scan or the scan moved slowly, there may be blockage issues or problems with your liver. If the tracers are found in other areas, this could indicate a leak.
If the results of your gallbladder radionuclide scan show problems, your doctor may want to take immediate action. This could include surgery or medication. In all likelihood, you’ll undergo more testing so that your doctor has a higher level of certainty regarding your condition.