X-Ray

What is an X-ray?

An X-ray is a quick, painless test that produces images of the structures inside your body — particularly your bones.

X-ray beams can pass through your body, but they are absorbed in different amounts depending on the density of the material they pass through. Dense materials, such as bone and metal, show up as white on X-rays. The air in your lungs shows up as black. Fat and muscle look like varying shades of gray.

For some types of X-ray tests, contrast medium — such as iodine or barium — is introduced into your body to provide greater detail on the X-ray images. Some people experience side effects from contrast material. X-ray beams also expose you to small doses of radiation, but the benefits from these tests far outweigh the risks.

Your child's X-ray

If a young child is having an X-ray, restraints or other immobilization techniques may be used to help keep him or her still. These will not harm your child and will prevent the need for a repeat procedure, which may be necessary if the child moves during the X-ray exposure. You may be allowed to remain with your child during the test. If you remain in the room during the X-ray exposure, you're typically asked to wear a lead apron to shield you from unnecessary exposure.

During your examination

X-rays are performed at most doctors' offices, dentists' offices, emergency rooms and hospitals — wherever an X-ray machine is available. The machine produces a tiny burst of radiation, at a safe level, that passes through your body and records an image on film or on a specialized plate. You can't feel the X-ray passing through you.

A technologist positions your body to obtain the necessary views. He or she may use pillows or sandbags to help you hold the proper position. During the X-ray exposure, you remain still and hold your breath to avoid moving, which can cause the image to blur.

An X-ray procedure may take only a few minutes for a bone X-ray, or more than an hour for more-involved procedures, such as those using a contrast medium.

After your examination

After an X-ray, you generally can resume normal activities. Routine X-rays usually have no side effects. However, if you receive an injection of contrast medium before your X-rays, call your doctor if you experience pain, swelling or redness at the injection site. Ask your doctor about other signs and symptoms to watch for pertaining to your specific X-ray procedure.

X-rays are saved on film or digitally on computers. Digital images can be viewed on-screen within minutes. A radiologist typically views and interprets the results and sends a report to your doctor, who then explains the results to you. In an emergency, your X-ray results can be made available to your doctor in minutes.