A gallium scan is a test that uses radioactive material to look for infection in the body. It is a type of nuclear medicine exam.
See also: Gallium scan of the lung
Liver gallium scan; Bony gallium scan
How the test is performed:
The health care provider will tie a rubber band (tourniquet) around your upper arm, and inject a radioactive material called gallium into a vein.
The gallium travels through the bloodstream and collects in the bones and certain organs.
Your health care provider will tell you to return at a later time to be scanned. If your health care provider thinks you have an acute inflammatory disease, the scan is done 4 - 6 hours after the injection. Otherwise, the scan is taken 24 - 48 hours (occasionally 72 hours) after the injection.
You will lie on your back on the scanner table. A special camera detects where the gallium has gathered in the body.
You must lie still during the scan, which takes 30 - 60 minutes.
How to prepare for the test:
The night before the test, a laxative may be necessary to clean out the bowel so that stool does not interfere with the test. An enema may instead be given 1 - 2 hours before the test.
Food and liquids are not restricted. You must sign a consent form. Remove all jewelry and metal objects.
How the test will feel:
The enema may be uncomfortable but does not cause pain. The injection will feel like a sharp prick, and the site may be tender to the touch for a few minutes.
The hardest part of the scan is holding still, as the scan itself is painless. Before the scan, some adjustments may be made to make the patient more comfortable.
Why the test is performed:
This test may be performed in the search for an unknown source of fevers. Gallium collects in areas of inflammation, which may be due to an abscess or tumor. Combined with other imaging, such as CT , hidden disease may be detected.
Gallium normally collects in bones, the liver, spleen, the large bowel, and breast tissue.
What abnormal results mean:
Gallium detected outside the normal areas (areas of increased uptake) can indicate infection, inflammation, or possibly tumors, including Hodgkin's disease or non-Hodgkin's lymphoma .
What the risks are:
There is a minimal risk of radiation exposure (less than with x-rays or CT scans). Radiation exposure of any sort is not usually recommended for pregnant or nursing women or for young children unless the benefits of the test exceed the risks.
Not all cancers show up on a gallium scan.
Segerman D, Miles KA. Radionuclide imaging: general principles. In: Grainger RC, Allison D, Adam, Dixon AK, eds. Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 7.