CT Scan stands for Computed Tomography Scan. It is also known as CAT Scan i.e. Computer Axial Tomography Scan. CT Scan is an X-ray technique that produces images of your body visualizing internal structures in cross section, rather than the overlapping images typically produced by conventional X-rays.

CT Scan is a medical imaging method employing tomography created by computer processing. It produces a series of detailed pictures of areas inside the body, taken from different angles. These pictures are created by a computer linked to an x-ray machine.

How is CT Scan different From conventional X-Rays?

In CT Scan technique, digital geometry processing is used to generate a three-dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.

Conventional X-ray exams use a stationary X-ray machine to focus beams of radiation on a particular area of your body to produce two-dimensional images on film or a digital detector, much like a photograph. But CT scans use an X-ray unit that rotates around your body and a powerful computer. The result with CT scans is a set of cross-sectional images, like slices, of the inside of your body.

How Does CT Scan Work?

A CT scanner emits a series of narrow beams through the human body as it moves through an arc, unlike an X-ray machine which sends just one radiation beam. Thus the resulting picture is far more detailed than an X-ray one.

Inside the CT scanner there is an X-ray detector which can see hundreds of different levels of density. It can see tissues inside a solid organ. This data is transmitted to a computer, which builds up a 3-D cross-sectional picture of the part of the body and displays it on the screen.

The patient should wear loose fitting clothes for an effective CT Scan. Sometimes a contrast dye is used because it shows up much more clearly on the computer screen. This improves the picture of some blood vessels or tissues. If a patient is allergic to contrast material he/she should tell the doctor beforehand. There are some medications that reduce allergic reactions to contrast materials.

When is a CT Scan recommended?

Doctors recommend a CT scan for a wide variety of reasons.A conventional X-ray of your abdomen, for example, shows your bones as well as subtle overlapping outlines of your liver, stomach, intestines, kidney and spleen. A CT scan, however, clearly reveals these bones and organs as well as their inner structure and detailed anatomy of your pancreas, adrenal glands, kidneys and blood vessels.

CT Scan is normally recommended to:

· Diagnose muscle and bone disorders, such as bone tumors and fractures
· Pinpoint the location of a tumor, infection or blood clot
· Guide procedures such as surgery, biopsy and radiation therapy
· Detect and monitor diseases such as cancer or heart disease
· Detect internal injuries and internal bleeding

CT scanning is useful to get a very detailed 3-D image of certain parts of the body, such as soft tissues, the pelvis, blood vessels, the lungs, the brain, abdomen, and bones. CT Scans are often better for looking at cancer, pneumonia, abnormal chest x-rays, bleeding in the brain (especially from injury).