CT SCAN

Computed tomography (CT) is a diagnostic imaging technique that allows various parts of the body to be examined for the diagnosis and study of numerous other diseases. It is a radiological examination in which data collected from the passage of various X-ray beams over the affected area are reprocessed by a computer to reconstruct a three-dimensional image of different tissue types.

Because the examination was once conducted along a single axis, with parallel sections perpendicular to the length of the body, as if the body were ideally “sliced,” it was referred to as computed axial tomography. From this name comes the acronym TAC, by which it is still commonly called today. With more modern multilayer machines, however, the term is a misnomer because computed tomography is no longer just “axial”; images are acquired using a spiral technique that takes advantage of table motion and thus allows for three-dimensional images.

Because computed tomography, in all its variants, employs X-rays, the examination is contraindicated in pregnancy. In these and other cases (e.g., in young subjects), where it is important to avoid exposure to ionizing radiation, Magnetic Resonance Imaging (or MRI), which does not pose this risk, is preferred.