A chest x ray is a painless, noninvasive test that
creates pictures of the structures inside your chest, such as your heart and
lungs. "Noninvasive" means that no surgery is done and no instruments are
inserted into your body.
This test is done to find the cause of symptoms such
as shortness of breath, chest pain, chronic cough (a cough that lasts a long
time), and fever.
Overview
X rays are electromagnetic waves. They use ionizing
radiation to create pictures of the inside of your body.
A chest x ray takes pictures of the inside of your
chest. The different tissues in your chest absorb different amounts of
radiation. Your ribs and spine are bony and absorb radiation well. They
normally appear light on a chest x ray. Your lungs, which are filled with air,
normally appear dark. A disease in the chest that changes how radiation is
absorbed also will appear on a chest x ray.
Chest X Ray
Figure A shows a cross-section of a
chest. Figure B shows an x-ray image of a chest. Roll your mouse over the terms
on right side of the x-ray image to highlight the internal structures of the
chest on both figures.
Chest x rays help doctors diagnose conditions such
as pneumonia,
heart
failure, lung cancer,
lung
tissue scarring, and
sarcoidosis
(sar-koy-DO-sis). Doctors also may use chest x rays to see how well treatments
for health problems are working. Also, doctors often use chest x rays before
surgery to look at the structures in the chest.
Chest x ray is the most common x-ray test used to
diagnose health problems.
Outlook
Chest x rays have few risks. The amount of radiation
used in a chest x ray is very small. Sometimes, a lead apron may be used to
protect certain parts of your body from the radiation.
A chest x ray gives out a radiation dose similar to
the amount of radiation you're naturally exposed to over 10 days. Chest x rays
use a smaller amount of radiation than other imaging tests.
Other Names for a Chest X Ray
Chest radiography (RA-de-OG-ra-fee)
CXR
Who Needs a Chest X Ray?
People who have symptoms such as shortness of
breath, chest pain, chronic cough (a cough that lasts a long time), or fever
may need chest x rays. The test can help find the cause of these symptoms.
Chest x rays look for conditions such as pneumonia,
heart
failure, lung cancer,
lung
tissue scarring, or
sarcoidosis.
The test also is used to check how well treatments for health problems are
working.
People who test positive for tuberculosis
(tu-ber-kyu-LO-sis) exposure on skin tests, but have no symptoms, also may need
chest x rays.
Sometimes, doctors order more chest x rays within
hours, days, or months of an earlier chest x ray. This allows them to follow up
on a condition.
People who are having certain types of surgery also
may need chest x rays. Doctors often use this test before surgery to look at
the structures inside the chest.
What To Expect Before a Chest X Ray
You don't have to do anything special to prepare for
a chest x ray. However, you may want to wear a shirt that's easy to take off.
Before the test, you'll be asked to undress from the waist up and wear a
gown.
You also may want to avoid wearing jewelry and other
metal objects. You'll be asked to take off any jewelry, eyeglasses, and metal
objects that might interfere with the x-ray picture. Let the x-ray technician
(a person specially trained to do x-ray tests) know if you have any body
piercing on your chest.
Let your doctor know if you're pregnant or may be
pregnant. In general, women should avoid all x-ray tests during pregnancy.
Sometimes, though, having an x ray is important to the health of the mother and
fetus. If an x ray is needed, the technician will take extra steps to protect
the fetus from radiation.
What To Expect During a Chest X Ray
Chest x rays are done at doctors' offices, clinics,
hospitals, and other health care facilities. The location depends on the
situation. An x-ray technician performs the test. This person is specially
trained to do x-ray tests.
The entire test usually takes about 15 minutes.
During the Test
Depending on your doctor's orders, you'll stand,
sit, or lie for the chest x ray. The technician will help position you
correctly. He or she may cover you with a heavy lead apron to protect certain
parts of your body from the radiation.
The x-ray equipment usually consists of two parts.
One part, a box-like machine, holds the x-ray film or a special plate that
records the picture digitally. You will sit or stand next to this machine. The
second part is the x-ray tube, which is located about 6 feet away.
Before the pictures are taken, the technician will
walk behind a wall or into the next room to turn on the x-ray machine. This
helps reduce his or her exposure to the radiation.
Usually, two views of the chest are taken. The first
is a view from the back. The second is a view from the side.
For a view from the back, you'll sit or stand so
that your chest rests against the image plate. The x-ray tube will be behind
you. For the side view, you'll turn to your side and raise your arms above your
head.
If you need to lie down for the test, you'll be
placed on a table that contains the x-ray film or plate. The x-ray tube will be
over the table.
You'll need to hold very still while the pictures
are taken. The technician may ask you to hold your breath for a few seconds.
These measures help prevent a blurry picture.
Although the test is painless, you may feel some
discomfort from the coolness of the exam room and the coldness of the recording
plate. If you have arthritis or injuries to the chest wall, shoulders, or arms,
you may feel discomfort holding a position during the test. The technician may
be able to help you find a more comfortable position.
When the test is done, you'll need to wait while the
technician checks the quality of the x-ray pictures. He or she needs to make
sure that the pictures are good enough for the doctor to use.
What To Expect After a Chest X Ray
You usually can go back to your normal routine right
after a chest x ray.
A radiologist will analyze, or "read," your x-ray
images. A radiologist is a doctor who is specially trained to supervise x-ray
tests and look at the x-ray pictures.
The radiologist will then send a report to your
doctor (who ordered the x-ray test). Your doctor will discuss the results with
you.
In an emergency, you will get the x-ray results
right away. Otherwise, it may take 24 hours or more. Talk to your doctor
about when you should expect the results.
What Does a Chest X Ray Show?
Chest x rays show the structures in and around the
chest. The test is used to look for and track conditions of the heart, lungs,
bones, and chest cavity. For example, chest x-ray pictures may show signs of
pneumonia,
heart
failure, lung cancer,
lung
tissue scarring, or
sarcoidosis.
Chest x rays do have limits. They only show
conditions that change the size of a tissue or how radiation is absorbed. Also,
chest x rays create two-dimensional pictures. This means that denser
structures, like bone or the heart, may hide some signs of disease. Very small
cancers and
blood
clots in the lungs usually don't show up on chest x rays.
For these reasons, other tests may be needed to
confirm a diagnosis.
What Are the Risks of a Chest X Ray?
Chest x rays have few risks. The amount of radiation
used in a chest x ray is very small. Sometimes, a lead apron may be used to
protect certain parts of your body from the radiation.
The test gives out a radiation dose similar to the
amount of radiation you're naturally exposed to over 10 days. Chest x rays use
a smaller amount of radiation than other imaging tests.
Key Points
A chest x ray is a painless, noninvasive test
that creates pictures of the structures inside your chest, such as your heart
and lungs.
This test is done to find the cause of symptoms
such as shortness of breath, chest pain, chronic cough (a cough that lasts a
long time), and fever.
The test helps doctors diagnose conditions such
as pneumonia,
heart
failure, lung cancer,
lung
tissue scarring, and
sarcoidosis.
Doctors also may use chest x rays to see how well treatments for health
problems are working. Also, doctors often use chest x rays before certain types
of surgery to look at the structures in the chest.
X rays use ionizing radiation to create pictures
of the inside of your body. Chest x ray is the most common x-ray test used to
diagnose health problems.
Chest x rays have few risks. The amount of
radiation used in one chest x ray is very small. Sometimes, a lead apron may be
used to protect certain parts of your body from the radiation.
You don't have to do anything special to prepare
for a chest x ray. However, you may want to wear a shirt that's easy to take
off. You also may want to avoid wearing jewelry and other metal objects.
Before the test, let your doctor know if you're
pregnant or may be pregnant. In general, women should avoid all x-ray tests
during pregnancy. Sometimes, though, having an x ray is important to the health
of the mother and fetus. If an x ray is needed, the technician will take extra
steps to protect the fetus from radiation.
A chest x ray usually takes about 15 minutes.
You'll sit, stand, or lie for the test. Usually, two views of the chest are
taken. The first view is from the back. The second view is from the side.
You'll need to hold very still while the pictures are taken. The technician may
ask you to hold your breath for a few seconds. These measures help prevent
blurry pictures.
You usually can go back to your normal routine
right after a chest x ray. In an emergency, you will get the x-ray results
right away. Otherwise, it may take 24 hours or more. Talk to your doctor about
when you should expect the results.
Chest x rays do have limits. They only show
conditions that change the size of a tissue or how radiation is absorbed. Also,
chest x rays create two-dimensional pictures. This means that denser
structures, like bone or the heart, may hide some signs of disease. Very small
cancers and
blood
clots in the lungs usually don't show up on chest x rays. For these
reasons, other tests may be needed to confirm a diagnosis.