X-ray or Computed Radiography 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 appear as varying shades of gray.
For some types of X-ray tests, a contrast medium — such as iodine or barium — is introduced into your body to provide greater detail on the X-ray images.
X-ray technology is used to examine many parts of the body.
Some people worry that X-rays aren’t safe because radiation exposure can cause cell mutations that may lead to cancer. But the amount of radiation you’re exposed to during an X-ray is so small that the risk of any damage to cells in your body is extremely low. Some may receive more radiation from the sun than an x-ray.
However, if you’re pregnant or suspect that you may be pregnant, tell your doctor before having an X-ray. Though the risk of most diagnostic X-rays to an unborn baby is small, your doctor may consider another imaging test, such as ultrasound.
The machine produces a tiny burst of radiation, at a safe level, that passes through your body and records an image 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.
X-rays are saved 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 within 48 hours, who then explains the results to you.