How It Is Done
A lung scan is usually done by a
nuclear medicine technologist. The scan pictures are usually interpreted by a
nuclear medicine specialist.
need to remove any jewelry that might interfere with the scan. You may need to
take off all or most of your clothes, depending on which area is being examined
(you may be allowed to keep on your underwear if it does not interfere with the
test). You will be given a cloth or paper covering to use during the
During the scan, you will either lie on your back with the
scanning camera positioned over or under your chest, or you will sit with the camera
positioned next to your chest. The camera does not produce any radiation, so
you are not exposed to any more radiation while the scan is being
For the ventilation scan, a mask
will be placed over your mouth and nose. Or you may have a nose clip on your
nose and a tube in your mouth that you use for breathing. You will inhale the
tracer gas or mist through the mask or tube by taking a deep breath and then
holding it. The camera will scan for radiation released by the tracer and
produce pictures as the tracer moves through your lungs. You may be asked to
breathe the gas in and out through your mouth for several minutes. You may then
be asked to hold your breath for short periods (about 10 seconds) and to change
positions so your lungs can be viewed from other angles. The camera may move to
take pictures from different angles. You need to remain very still during the
scans to avoid blurring the pictures.
Afterward, the radioactive
gas or mist will clear from your lungs as you breathe.
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
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.