Chest X-Ray Test

What Does a Chest X-Ray Test For?

A chest x-ray produces images of the organs in your chest, including the heart and lungs. A very small amount of radiation is used to produce an image.

The chest x-ray can show if you have fluid buildup in the lungs or if your heart has become enlarged.

In heart failure diagnosis, the chest x-ray is one of the first tests performed to determine the cause of your heart failure symptoms. The test identifies or rules out other possible causes of shortness of breath and fluid buildup in the lungs, including lung problems such as pneumonia or emphysema.

A Chest X-Ray Test May Be Used To:

• Look at the structures of the chest (bones, heart, lungs)
• Evaluate placement of devices (pacemakers, defibrillators) or tubes placed during hospitalization for treatment and monitoring ( catheters, chest tubes)
• Diagnose lung and cardiac diseases

How is a Chest X-Ray Performed?

A machine beams x-rays that pass through the chest and onto a special film or digital recording plate placed behind your back or to your side, producing a black-and-white image of the organs inside the chest.

Different parts of the body absorb x-rays differently: the more the x-ray is absorbed, the lighter the tissue appears in the final image.

Bone is very dense and absorbs most x-rays, so little of the x-ray reaches the film plate, causing bones to appear white on the final image.

Softer tissue, such as the heart, is less dense and allows more x-rays to pass through to the film plate, causing the heart to appear gray on an x-ray film.

Hollow organs, such as the lungs and the air in them, allow most x-rays to pass through, so they appear black in the final image. If there is fluid buildup in the lungs, more of the x-rays will be blocked, so these areas will appear lighter than normal lungs.

If you are unable to stand, you may be asked to lie on a table with the x-ray beam above you and the film box beneath you.

A chest x-ray usually takes about 15 minutes.