Computed tomography, also called computerized axial tomography (CAT) scan, is used to create cross-sectional images of structures in the body. In this procedure, x-rays are taken from many different angles and processed through a computer to produce a three-dimensional (3-D) image called a tomogram.
Computed tomography is used to detect abnormalities such as blood clots, cysts, fractures, infections, and tumors in internal structures (bones, muscles, organs, soft tissue). The procedure also may be used to guide the placement of instruments within the body.
Your doctor may order a contrast agent (such as an iodine based dye or barium solution) to be administered prior to CT scan to allow organs and structures to be seen more easily. Contrast agents can be administered through a vein (IV), by injection, or taken orally. Generally, patients are instructed not to eat or drink for a few hours prior to contrast injection or IV because the dye may cause stomach upset.