What you can expect

By Mayo Clinic Staff

A bone scan is a nuclear imaging procedure. In nuclear imaging, tiny amounts of radioactive materials (tracers) are injected into a vein and taken up in varying amounts at different sites in the body. Areas of the body where cells and tissues are repairing themselves most actively take up the largest amounts of tracer. Nuclear images highlight these areas, suggesting the presence of abnormalities characteristic of disease or injury.

A bone scan can be divided into two basic parts:

  • The injection. You will receive an injection of tracers into a vein in your arm. Depending on the reason your doctor has ordered the scan, images of the injection may be taken immediately or after enough time has passed to allow the tracers to circulate and be absorbed by your bones — generally two to four hours. You may be allowed to leave the radiology department during this time. Your doctor will ask you to drink extra water to remove unabsorbed radioactive material from your system.
  • The scan. During the scan, you'll be asked to lie still on a table while an arm-like device supporting a tracer-sensitive camera passes back and forth over your body. This is painless. A scan of your entire skeleton takes as long as 60 minutes. Scanning a limited area of your body takes less time.

In some cases, your doctor might order a three-phase bone scan, which includes a series of images taken at different times. A number of images are taken as the tracer is injected, then shortly after the injection, and again three to four hours later.

To better see some bones in your body, your doctor might order additional imaging called single-photon emission computerized tomography (SPECT). This can help analyze conditions that are especially deep in your bone or in places that are difficult to see with static or 2-D (planar) images. For a SPECT scan, the camera rotates around your body, taking images as it rotates. The additional SPECT images take approximately 30 minutes.

After the test

Once inside your body, the tracers don't remain active for long. The radioactivity is mostly removed after one day and completely eliminated by two days. You should feel no side effects after the procedure, and no aftercare is necessary.

Jan. 26, 2012