Computed Tomography (CT) System, also know as a "CAT Scan" is a medical diagnostic tool that allows the visualization of internal structures within the human body. This aids physicians in diagnosing disease, viewing internal abnormalities and assessing the extent of trauma damage.

During a typical CT procedure, the patient is placed on a table. The table then moves the patient through the gantry (a donut-shaped device), which houses an X-ray tube and detector array. For each image acquired, the X-ray tube rotates around the patient and the X-rays pass through the patient to the detector array, and thousands of X-ray measurements are acquired. The computer then processes this information and displays the corresponding images on a computer screen. (See Figure 1) This imaging technique avoids any superimposition of organs or tissues upon one another that might occur during other types of X-ray tomographic studies.

The CT exam creates images analogous to a single slice of bread from a whole loaf or a slice from an orange. (See Figure 2) Hence, the word ‘slice’ is often used to describe a view of patient anatomy.

The quality of an image depends on the nature of the X-ray source and detectors, the number and speed of the measurements made, the details of the reconstruction technique (algorithm), the machine characteristics, and the methods of data display and interpretation. The computer allows healthcare professionals to shade, rotate, correlate and measure anatomy in the image. This data can be manipulated to derive even more precise clinical information. While conventional X-ray can discern tissue density difference of five percent, CT can distinguish a density difference of 1 percent or less, aiding in diagnostic confidence.

Figure 1	Figure 2