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URL of this page: https://medlineplus.gov/nuclearscans.html

Nuclear Scans

Also called: Radioisotope scans, Radionuclide scans

Summary

What is a nuclear scan?

A nuclear scan is a type of medical imaging test that uses a small amount of radioactive material, called a radiotracer. This scan shows how organs and tissues are working, not just what they look like.

After the radiotracer is given, a special camera detects the radiation coming from inside the body. This allows your health care provider to see organ function, blood flow, or tissue activity, which can help diagnose conditions and check how well treatment is working.

Who needs a nuclear scan?

Nuclear scans may be used to find disease, target certain cells, and monitor response to treatment. They are commonly used to:

  • Check how organs such as the heart, lungs, or kidneys are working
  • Find disease early, sometimes before changes can be seen on other imaging tests
  • Perform bone scans
  • Evaluate the thyroid
  • Check how well cancer treatment is working

How do you prepare for a nuclear scan?

Before the scan, you will receive a small amount of radiotracer. This may be given as:

  • An injection
  • A pill or liquid to swallow
  • A gas to inhale

The radiotracer travels to the part of the body being examined. How much of the tracer is absorbed can help show how well an organ or tissue is functioning.

Always tell your provider if you are pregnant, think you may be pregnant, or are breastfeeding.

How is a nuclear scan done?

You may be asked to change clothes and remove jewelry or other items that could interfere with the scan. Ask your provider if there are any special instructions before your scan.

Depending on the type of nuclear scan, you may:

  • Lie on a table
  • Sit in a chair
  • Stand
  • Walk on a treadmill or ride a stationary bike (for some heart scans)

You will be asked to stay as still as possible, unless movement is part of the test.

A special imaging device, such as a gamma camera, single-photon emission computed tomography (SPECT) scanner, or positron emission tomography (PET) scanner, detects radiation from the tracer and creates images.

The length of the scan depends on the type of test and the area being examined. Some scans take only minutes. Others may include waiting periods or require you to return later the same day or over several days.

What should you expect after a nuclear scan?

Most people can return to normal activities right away. Drinking fluids may help your body clear the radiotracer.

A specialist called a radiologist reviews the images and shares the results with your provider.

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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.