How It Is Done continued...
Afterward, the radioactive gas or mist will clear from your lungs as you breathe.
The ventilation scan takes about 15 to 30 minutes.
For the perfusion scan, the technologist cleans the site on your arm where the radioactive tracer will be injected. A small amount of the radioactive tracer is then injected.
After the radioactive tracer is injected, the camera will scan for radiation released by the tracer and produce pictures as the tracer moves through your lungs. The camera may be repositioned around your chest to get different views. You need to remain very still during the scans to avoid blurring the pictures.
The perfusion scan takes about 5 to 10 minutes.
How It Feels
You may find that breathing through the mask during the ventilation scan is uncomfortable, especially if you feel very short of breath. But you will be given plenty of oxygen through the mask.
You may feel nothing at all from the needle puncture when the tracer is injected, or you may feel a brief sting or pinch as the needle goes through the skin. Otherwise, a lung scan is usually painless. You may find it hard to remain still during the scan. Ask for a pillow or blanket to make yourself as comfortable as possible before the scan begins.
Allergic reactions to the radioactive tracer are very rare. Most of the tracer will be eliminated from your body (through your urine or stool) within a day, so be sure to promptly flush the toilet and thoroughly wash your hands with soap and water. The amount of radiation is so small that it is not a risk for people to come in contact with you following the test.
Occasionally, some soreness or swelling may develop at the injection site. These symptoms can usually be relieved by applying moist, warm compresses to your arm.
There is always a slight risk of damage to cells or tissue from being exposed to any radiation, including the low level of radiation released by the radioactive tracer used for this test.