What is a CAT Scan? A CT or CAT scan is a medical imaging device that combines the use of x-rays with computers to produce images that allow physicians to look inside a patient's body. Unlike conventional radiographs, a CT scan can produce clear, extremely detailed pictures of the body's internal structures. It can separate bone from muscle and fat in the part of the body being examined. Much like a conventional radiograph, x-rays pass through the person's body and a computer then reconstructs the information into cross sectional images. These cross sectional images allow the radiologist to evaluate the internal organs as though we looked at the body separated into a series of thin "slices". Having a CT scan can assist your doctor in helping make a diagnosis so he/she can adequately treat your problem. The radiologist performs and interprets the examination and relays the information in a report which is then sent and discussed with your physician. Your physician will then, in turn, discuss the report with you.