What is an X-Ray?

X-rays use external radiation to produce images of the body, its organs, and other internal structures to diagnose a problem. X-rays pass through body tissues onto specially treated plates (similar to camera film). It makes a "negative" type picture. Computers and digital media may be used in place of films.

Different parts of the body allow varying amounts of the X-ray beams to pass through. Images are produced in degrees of light and dark, depending on the amount of X-rays that penetrate the tissues. The more solid a structure is, the whiter it appears on the picture. The soft tissues in the body (such as blood, skin, fat, and muscle) allow most of the X-ray to pass through and appear dark gray on the film. A bone or a tumor, which is denser than the soft tissues, allows few of the X-rays to pass through and appears white on the X-ray. At a break in a bone, the X-ray beam passes through the broken area and appears as a dark line in the white bone.

How is it Done?

  • You will need to take off any clothing, jewelry, or other objects that might prevent a clear picture. If you are asked to remove clothing, you will be given a gown or other item to wear.
  • Your body will be positioned in a way that carefully places the part to be X-rayed between the X-ray machine and the film. You may be asked to stand up, lie flat on a table, or lie on your side on a table, depending on the X-ray view your healthcare provider has asked for. You may have X-rays taken from more than one position.
  • Body parts not being X-rayed may be covered with a lead apron or shield to limit exposure to the X-rays.
  • Once you are positioned, the X-ray beam is focused on the area to be examined. It is very important to stay completely still while the X-ray is taken. Any movement may ruin the image and may require another X-ray to be done.
  • The radiologic technologist steps behind a protective window while the image is taken.
  • You will be asked to hold still for a few moments while the X-ray is taken and may be asked to hold your breath.

X-rays are painless and fast. However, you may feel some discomfort or pain while your body is being positioned for the X-ray, particularly if you’ve recently had surgery or been injured. The radiologic technologist will do what they can to minimize any discomfort or pain.

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This medical information is provided by Intermountain Healthcare. It has not been developed to replace medical advice provided by your health care provider.

Last review date: March 2017