Summary
The computed tomography (CT) scan is a medical imaging procedure that uses x-rays and digital computer technology to create cross-section images of the body. It can make an image of every type of body structure at once, including bone, blood vessels and soft tissue. The CT scan may also be referred to by its older name of computed axial tomography or CAT scan.

The computed tomography (CT) scan is a medical imaging procedure that uses x-rays and digital computer technology to create detailed two- or three-dimensional images of the body. Unlike other forms of medical imaging, the CT scan can make an image of every type of body structure at once, including bone, blood vessels and soft tissue.

The CT scanning equipment consists of a large gantry (a supporting structure) with a circular hole. Inside the gantry is a rotating ring that carries the x-ray source and electronic x-ray detectors. An attached table slides the fully reclined person into the hole.

Multiple x-ray projections are taken in thin cross-sections along the person’s body (imagine a loaf of sliced bread). The detectors collect the x-ray information from each cross-section and send them to a special computer that combines them into an image.

The CT scan may also be referred to by its older name of computed axial tomography or ‘CAT’ scan.