A computed tomography (CT) scan is an imaging method that uses x-rays to create pictures of cross-sections of the body.
Related tests include:
- Abdominal and pelvis CT scan
- Cranial or head CT scan
- Cervical, thoracic, and lumbosacral spine CT scan
- Orbit CT scan
- Chest CT scan
Alternative Names
CAT scan; Computed axial tomography scan; Computed tomography scan
How the Test is Performed
You will be asked to lie on a narrow table that slides into the center of the CT scanner.
Once you are inside the scanner, the machine's x-ray beam rotates around you. Modern spiral scanners can perform the exam without stopping.
A computer creates separate images of the body area, called slices. These images can be stored, viewed on a monitor, or printed on film. Three-dimensional models of the body area can be created by stacking the slices together.
You must stay still during the exam, because movement causes blurred images. You may be told to hold your breath for short periods of time.
Complete scans most often take only a few minutes. The newest scanners can image your entire body in less than 30 seconds.