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Alternative names Return to top
Scintigraphy - boneDefinition Return to top
A bone scan is a test that detects areas of increased or decreased bone metabolism (turnover). The test is performed to identify abnormal processes involving the bone such as tumor, infection, or fracture.How the test is performed Return to top
A radiotracer (bone-seeking radionuclide) is injected into the bloodstream through a vein. As it decays, the radiotracer emits gamma radiation, which is detected by a camera that slowly scans your body. The camera captures images of how much radiotracer collects in the bones.
If a bone scan is performed to evaluate possible fracture or infection, images will be performed shortly after the radiotracer injection, as well as after a 3-hour delay, when the tracer has collected in the bones. This is called a 3-phase bone scan.
To evaluate metastatic bone disease, images are obtained only after the 3-hour delay. Information from the camera is recorded in a computer, which then processes the data and creates an image.
The scanning part of the test will last about an hour and may require moving to various positions.
How to prepare for the test Return to top
You must remove jewelry and other metal objects. You may be asked to wear a hospital gown.
For infants and children:
The preparation you can provide for this test depends on your child's age and experience. For specific information regarding how you can prepare your child, see the following topics:
How the test will feel Return to top
There is a small amount of pain when the needle is inserted. During the scan there is no pain. You must remain still during the examination, and you will be instructed when to change positions by the technologist.
You may experience some discomfort due to lying still for a prolonged period of time.
Why the test is performed Return to top
Detecting areas of abnormal bone metabolism is valuable in determining whether there is associated tumor, fracture, infection (osteomyelitis), or an underlying metabolic disorder.
Normal Values Return to top
Normal distribution areas appear uniform and gray throughout all the bones in your body.
What abnormal results mean Return to top
There should be no areas of asymmetric increased or decreased distribution of the radionuclide. "Hot spots" are areas where there is increased bone uptake (accumulation) of the radiotracer; these appear black. "Cold spots" are areas where there is less uptake of the radiotracer. These appear light or white.What the risks are Return to top
If you are pregnant or nursing, the test may be postponed to prevent exposing the fetus to radiation.
The amount of radioactivity in the injection is very small, and virtually all activity is gone from the body within 2-3 days. Although it is extremely rare with bone scanning agents, a person may develop rash, swelling, or anaphylaxis (severe allergic response).
There is a slight risk of infection or bleeding with any intravenous injection.
Special considerations Return to top
Some abnormalities that may be identified on radionuclide bone scans include:
It is important to understand that bone scan findings must be correlated with other imaging studies, in addition to clinical information. You should always discuss the significance of abnormal findings with your health care provider.
Update Date: 7/21/2004 Updated by: Jeffrey J. Brown, MD, FACR, Mallinckrodt Institute of Radiology, Washington, University School of Medicine, St. Louis, MO. Review Provided by VeriMed Healthcare Network.
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Page last updated: 28 October 2004 |