An X-ray is a quick, painless test that produces images of the structures inside your body — particularly your bones.
X-ray beams pass through your body, and 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 shades of gray.
Reasons your physician might order an X-ray:
- Dental decay. Dentists use X-rays to check for cavities in your teeth.
- Osteoporosis. Special types of X-ray tests can measure your bone density.
- Bone cancer. X-rays can reveal bone tumors.
- Lung infections or conditions. Evidence of pneumonia, tuberculosis or lung cancer can show up on chest X-rays.
- Digestive tract problems. Barium, a contrast medium delivered in a drink or an enema, can help reveal problems in your digestive system.
- Swallowed items. If your child has swallowed something such as a key or a coin, an X-ray can show the location of that object.
What to wear for your X-ray
In general, you undress whatever part of your body needs examination. You may wear a gown during the exam, depending on which area is being X-rayed. You may also be asked to remove jewelry, eyeglasses and any metal objects because they can show up on an X-ray.
What to expect for your X-ray
The machine produces a safe level of radiation that passes through your body and records an image on a specialized plate. You can't feel an X-ray.
A technologist positions your body to obtain the necessary views. He or she may use pillows or sandbags to help you hold the position. During the X-ray exposure, you remain still and sometimes hold your breath to avoid moving so that the image doesn't blur.
An X-ray procedure may take just a few minutes for a simple X-ray or longer for more-involved procedures.