A Computerized Axial Tomography (CAT) scan or CT scan is a way of X-raying a mass in the body that allows for one to see three-dimensional views of the mass. It can allow a neurologist to essentially look at "slices" of the brain for better diagnostics in locating cranial bleeds or the presence of a tumor. This type of imaging of other organs can reveal a great deal more information than a regular X-ray, which is two-dimensional.
A CAT scan tends to be completely painless, though it may require people to lie still for a period of time. Depending on the area for which one is having the scan, the patient may have to fast for four to six hours prior to the scan. This is particularly the case if one is having an abdominal/pelvic scan. In this case, one may also be asked to drink barium, a substance that shows up on the scan to identify any trouble or blockages in the intestines.
The CAT scan picture taking process usually only lasts a few minutes or less. It is usually the in-between time when pictures are not being taken that consumes the most time. A scan of the body can be completed in only about 30 minutes, in many cases.
A CAT scanner looks like a bed, or tube with a rounded device over the top. This device looks a bit like the handle of a light saber, and easily fits over the body. This is the picture taking part of the scan, and it can move both up and down, and from side to side.
While one is taking a CAT scan, one may be instructed to hold one's breath for short periods of time, and then to breathe out. This will be the case with those have abdominal/pelvic or chest scans.
People are concerned that the amount of radiation used in a CAT scan may be dangerous. It is true that radiation used is considerably higher than that of an X-ray. For this reason, physicians don't normally request this type of imaging study unless it is necessary to rule out or rule in a serious illness. Physicians have also worked on reducing radiation exposure to the absolute minimum to avoid dangerous exposure.
For those who might undergo a single CAT scan, radiation exposure is thought to pose very limited risk. Even a few scans are unlikely to have long-term effects. Those who must undergo scans on a frequent basis may have a greater risk from radiation exposure. Usually, benefits of multiple scans outweigh risks.
Once the CAT scan is finished, patients are usually able to get up and pursue regular activities, unless the scan is used on someone with injuries impairing normal activities. Radiologists read the scan, and then report findings to a person's specialist or general practitioner. Unless a serious problem is noted right away, results can take up to a week. In fact for most, not being contacted immediately is a good sign, as it means that the problem suspected may not exist, or may not require further treatment.