A chest X-ray is a safe and painless test that uses a small amount of radiation
to take a picture of a person's chest. During the examination, an X-ray machine sends
a beam of radiation through the chest, and an image is recorded on special film or
This image includes organs and structures such as the heart, lungs, large blood
vessels, diaphragm, part of the airway, lymph nodes, the upper spine, ribs, collarbone,
The X-ray image is black and white. Dense body parts that block the passage of
the X-ray beam through the body, such as the heart and bones, appear white on the
X-ray image. Hollow body parts, such as the lungs, allow X-ray beams to pass through
them and appear black.
An X-ray technician takes the X-rays. Usually, two are taken: one from the back
of the chest if the child is old enough to stand up for the X-ray, and one from the
side. In younger children a picture from the front of the chest is taken as well as
from the side. In some cases, special views of the chest are taken.
Why It's Done
A chest X-ray is used to help find the cause of symptoms such as cough, shortness
of breath, or chest pain. It can detect signs of asthma, pneumonia, a collapsed lung,
heart problems (such as an enlarged heart), and broken ribs or lung damage after an
Chest X-rays can reveal small metal objects (such as coins) that might have been
swallowed. They can also help confirm that medical tubes have been placed in the right
locations in the lungs, heart, blood vessels, or stomach.
A chest X-ray doesn't require special preparation. Your child may be asked to remove
all clothing and jewelry from the waist up and change into a hospital gown because
buttons, zippers, clasps, or jewelry might interfere with the image.
Developing babies are more sensitive to radiation and are at more risk for harm,
so if your daughter is pregnant, tell her doctor and the X-ray technician.
Although the procedure may take 15 minutes or longer from start to finish, the
actual exposure time to radiation is usually less than half a second.
Your child will be asked to enter a special room that will most likely contain
a table and a large X-ray machine hanging from the ceiling. Parents are usually able
to accompany their child to provide reassurance and support.
A chest X-ray may be performed in a standing, sitting, or lying position. This
will depend on the condition of your child and the reason for the X-ray. The technician
will position your child, then step behind a wall or to an adjoining room to operate
Older kids will be asked to hold their breath and remain still for 2-3 seconds
while the X-ray is taken; infants may require gentle restraint. Keeping the chest
still is important to prevent blurring of the X-ray image. Two X-rays are usually
taken, one from the back and one from the side.
If your child is in the hospital and cannot easily be brought to the radiology
department, a portable X-ray machine can be brought to your child's bedside. Portable
X-rays are often used in emergency departments, intensive care units, or operating
rooms. In this case, only one X-ray might be taken, usually from the front.
What to Expect
Your child won't feel anything as the X-ray is taken. The X-ray room may feel cool
due to air conditioning used to maintain the equipment.
Positions required for the X-ray may feel uncomfortable, but they need to be held
for only a few seconds. If your child has an injury and cannot stay in the required
position, the technician might be able to find another position that's easier on your
child. Babies often cry in the X-ray room, especially if they're restrained, but this
won't interfere with the procedure.
If you stay in the room while the X-ray is being done, you'll be asked to wear
a lead apron to protect certain parts of your body. Your child's reproductive organs
will also be protected with a lead shield.
After the X-rays are taken, you and your child will be asked to wait a few minutes
while the images are processed. If they are blurred or unclear, the X-rays may need
to be redone.
Getting the Results
The X-rays will be looked at by a radiologist (a doctor who is specially trained
in reading and interpreting X-ray images). The radiologist will send a report to your
child's doctor, who will discuss the results with you and explain what they mean.
In an emergency, the results of a chest X-ray can be available within a short period
of time. Otherwise, results are usually ready in 1 or 2 days. In most cases, results
cannot be given directly to the patient or family at the time of the test.
In general, chest X-rays are very safe. Although any exposure to radiation poses
some risk to the body, the amount used in a chest X-ray is small and not considered
dangerous. It's important to know that radiologists use the minimum amount of radiation
required to get the best results.
Developing babies are more sensitive to radiation and are at greater risk for harm,
so if your daughter is pregnant, make sure to inform her doctor and the X-ray technician.
Helping Your Child
You can help your young child prepare for a chest X-ray by explaining the test
in simple terms before the procedure. It may help to explain that getting an X-ray
is much like posing for a picture. You can describe the room and the equipment that
will be used, and reassure your child that you'll be right there for support.
For older kids, be sure to explain the importance of keeping still while the X-ray
is taken so it won't have to be repeated.
If You Have Questions
If you have questions about why the chest X-ray is needed, speak with the doctor.
You can also talk to the X-ray technician before the procedure.