An X-ray is a diagnostic exam that produces images of the hard structures inside the body — particularly the bones.
During the exam, X-ray beams pass through the body and are absorbed in different amounts depending on the density of the material they pass through. Dense materials, such as bone and metal, are seen as white on X-rays, whereas air in the lungs shows up as black. Fat and muscle appear as shades of gray.
Some patients may be given a contrast medium — such as iodine or barium — to provide greater detail in the images.
X-ray exams can be done to examine the bones, teeth, chest, and abdomen.
A few conditions affecting the bones and teeth that can be diagnosed with the help of an X-ray include:
An X-ray can also identify abnormalities in the chest, such as:
Patients experiencing symptoms affecting their abdomen may need to undergo an X-ray to identify:
An X-ray exam may be performed at doctors’ offices, dentists’ offices, emergency rooms, clinics, and hospitals. During an exam, the machine produces a safe level of radiation that passes through the patient’s body and records an image on a specialized plate. Patients will not feel anything from the radiation.
The exam will begin with the technologist positioning the patient’s body to obtain the necessary views and placing pillows or sandbags to help the patient lie still for the duration of the exam. During the X-ray exposure, the patient will be instructed to remain still and sometimes hold their breath to avoid moving.
A simple X-ray procedure may take just a few minutes. More-involved procedures, such as those using a contrast medium, will take longer.