A computed tomography, or CT, scanner is a large, doughnut-shaped medical tool that utilizes X-rays to produce cross-sectional images of the internal structures of the body. This machine is used to perform a variety of imaging tests, including cranial, abdominal, orbit, thoracic or lumbosacral spine CT scans, notes MedlinePlus.
A CT scanner is made up of a circular opening, which the patient is wheeled through using a motorized table. This aperture, which measures 24 to 28 inches, contains an internal revolving structure. An X-ray tube is fastened on one side of this rotating frame, while detectors are mounted on the other side, explains Imaginis.
The machine works by passing a narrow, fan-shaped beam of X-rays around the patient while the rotating frame turns. Generally, CT scans involve several phases for data collection, where each phase can take between 10 and 50 rotations to complete, states the U.S. Food and Drug Administration.
With each rotation of the X-ray tube, the radiation detectors capture around 1,000 various angles called "profiles" of the scanned area. The snapshots are supplied to a dedicated computer, which constructs a two-dimensional image. These images can be displayed on a monitor, printed or stored in a database. Three-dimensional images can also be produced by digitally stacking the 2D images together.