What is a chest x-ray?

A chest x-ray is an image of the inside of your chest created by passing a small amount of radiation through your body. The brightest images in a chest x-ray are your bones, including your ribs and collarbone. But the chest x-ray also helps to evaluate the health of your cardiovascular system by providing shadowy images of your heart, lungs and major blood vessels, including the aorta, the large artery that transports blood away from the heart.


Chest x-rays usually show the chest in two views. The first view is taken from the back to the front, as you press your chest against the x-ray film or digital plate. It is called the posterior-anterior (PA) view. (When your doctor views the PA view, it actually looks as if it were taken from the front.) The second view is taken from the side and is called the lateral view.

A chest x-ray is a type of diagnostic radiology procedure used to examine the chest and the organs and structures located in the chest. Chest x-rays may be used to assess the lungs, as well as the heart (either directly or indirectly) by looking at the heart itself. Certain conditions of the heart may cause changes in the lungs and/or the vessels of the lungs. Changes in the normal structure of the heart, lungs, and/or lung vessels may indicate disease or other conditions.

Chest x-rays may provide important information regarding the size, shape, contour, and anatomic location of the heart, lungs, bronchi, great vessels (aorta, aortic arch, pulmonary arteries), mediastinum (an area in the middle of the chest separating the lungs), and the bones (cervical and dorsal spine, clavicles, shoulder girdle, and ribs).
A chest x-ray produces an image of the inside of the chest showing the bones, heart and blood vessels. Chest x-rays usually show the chest in two views: from the front and from the side.

Although chest x-rays are not as sophisticated as some other diagnostic technologies, they provide information that cannot be obtained in an examination. For instance, they can be valuable in initially evaluating:
  • The size of the heart.
  • The contour of the heart. Enlargement of a particular chamber or blood vessel may suggest heart failure or other abnormal functioning.
  • The size of the large blood vessels of the lungs. Enlarged blood vessels may suggest any of several heart defects or diseases—and indicate the need for more sophisticated tests.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.