Brain Imaging Tehnology: The CAT Scan

CAT Scans (also known as CT scans) can be a very helpful and life saving technological tool. C.A.T. stands for Computerized Axial Tomography. "Axial" means that the scan can rotate around the body's natural line of symmetry, which is the spine, to capture multiple pictures and put together a full image. "Tomography" is a series of cross-sectional pictures, taken in slices, of areas inside the body. The pictures, when put together, provide a three dimensional, structural image. CAT Scans can be used for various parts of the body, including the brain, spine, abdomen, chest, and pelvis. CAT scans are a combination of x-ray technologies and computer-imaging techniques. Therefore, CAT scans produced a more detailed picture than just an x-ray would. The machine itself is shaped somewhat like a donut, and the subject lays on a bench that slides through the center of the donut, where the machine captures the pictures of the body.

In 1972, the CAT scan was invented by two people in two different places simultaneously. Godfrey Newbold Hounsfield of EMI Central Research Laboratories and Allen McLeod Cormack of Tuft's University are credited with the invention.

CAT scans have been successful in finding tumors, blood clots, skull fractures, cysts, infections, and changes in the anatomy of one's body due to trauma. CAT scans are helpful in measuring bone density and evaluating osteoporosis, as well as detecting lung cancer.

There are several different types of CAT scans. Helical and spiral CAT scans are often used at trauma centers because they provide rapid and accurate pictures of internal organs that may be damaged due to trauma.

CAT scans are a blessing to the medical community and patients because the use of the scans decreases the demand for more invasive, surgical procedures. The CAT scans accomplish the goal of most exploratory procedures, without surgery, pain, and the necessary recovery. This saves time, money, and prevents the patient from having any additional discomfort.

Unfortunately, CAT scans cannot capture bodily movement, including but not limited to, a heart beat.

CAT scans are very safe and expose the subject to minimal amounts of radiation. There have not been any adverse reactions to a CAT scan. The possibility of an adverse reaction increases when doctors use an x-ray dye in the patient. The dye is an iodine based liquid injected into the vein known as an intravenous contrast. The dye is helpful to doctors because it makes organs and internal structures more visible. Rarely, life threatening side effects can occur.

Usually, patients are required to abstain from eating a few hours before the CAT scan. In preparation, patients may have to drink a chalk like beverage that helps to define the images in the CAT scan. A doctor may ask a patient to drink whole milk before having a CAT scan. The preparation instructions may vary due to the type of CAT scan and what the doctors are looking for. It is important to follow your doctor's instructions.

Citations:
"Computerized Axial Tomography." MedicineNet.com. 8/25/2005. Date Accessed 9/23/2008. http://www.medicinenet.com/cat_scan/article.htm

Howard, Pierce J. (2006). The Owner's Manual for The Brain. 3rd Edition. Austin, Texas: Bard Press.