Lung gallium scan is a type of nuclear scan that uses radioactive gallium (Ga) to identify swelling (inflammation) in the lungs.

This test is most often performed when there is evidence of inflammation in the lungs (sarcoidosis).

Gallium is injected into a vein. The scan will be taken 6 - 24 hours after the gallium is injected. (Test time depends on whether your condition is acute or chronic.)

During the test, you lie on a table that moves underneath a scanner called a gamma camera. The camera detects the rays the gallium releases. Images display on a computer screen.

During the scan, it is important that you keep still to get a clear image. The technician can help make you comfortable before the scan begins. The test will take about 30 - 60 minutes.

You must sign an informed consent form. Several hours to 1 day before the scan, you will get an injection of gallium at the hospital or doctor's office.

Just before the scan, remove jewelry, dentures, or other metal objects that can affect the scan. Take off the clothing on the upper half of your body and put on a hospital gown.

The injection of gallium will sting, and the puncture site may hurt for several hours or days when touched.

The scan is painless. However, you must stay still. This may cause discomfort for some patients. The wait between the injection and scan can cause some patients to become agitated.