Chest radiography, chest roentgenography, and chest films.

• To evaluate the lungs, as well as the chest cage, for the presence of abnormalities.
• To evaluate the size of the heart.
• To establish the size and location of an abnormality prior to performing other tests, such as a biopsy.
• To screen for lung disease in people who have occupational exposure to potentially toxic substances such as asbestos.

X-rays (electromagnetic energy emitted by an X-ray tube) are absorbed by the body tissue. When the tissue is exposed to special photographic film, various types of tissue show up as shadows, dark gray areas, or white opaque areas.

• You remove clothing and jewelry above the waist and don a hospital gown.
• If your hair is long, you must pin it up on your head so that no locks hang over your chest or shoulders.

• The technician positions you against the X-ray machine.
• You are asked to take a deep breath and hold it without moving while an X-ray picture is taken.
• Pictures are usually taken from the front and the side. Depending on the suspected problem, additional X-rays may be taken at different angles.

• You dress and are free to leave.
• The film is processed in a developing machine, and X-ray pictures are produced.

• If you move during the test, the image may be distorted.
• Images obtained with portable X-ray machines tend to be of poorer quality than those taken with stationary X-ray equipment. Portable X-rays are usually done only if you are hospitalized and physically unable to go to the X-ray department.

The doctor studies the X-ray picture and determines whether all chest structures look normal.

• It's relatively inexpensive and widely available.
• It's painless and fast.

• It involves exposure, although minimal, to radiation.
• It may not provide adequate information about lungs and other soft tissues.

• A normal X-ray usually requires no further testing.
• An abnormal X-ray may require monitoring (observation), confirmation by another test such as a chest CT scan or MRI, or a biopsy of the abnormality.