CAT Scans for Epilepsy

Another tool a neurologist uses to assist in diagnosing a case of epilepsy is the CAT scan, or Computerized Axial Tomography. The CAT scan, which was first introduced in the 1970s, allows neurologists to see the inside of the brain without surgery.

Most people with epilepsy have normal CAT scans however the CAT scan screens for abnormalities in the brain such as scar tissue, atrophy, strokes, tumors and abnormal blood vessels. Even with a normal CAT scan, a person can have epilepsy. In many cases, a cause for epilepsy is never found.

Neurologists often choose CAT scans over MRIs because of speed and availability. CAT scans offer lower resolution than MRIs and use radiation just like x-rays. The amount of radiation used is low and safe enough to be repeated several times.

Getting a CAT scan for epilepsy is easy and painless. An iodine based dye is injected in a vein before the patient is placed inside the donut like scanner. Those who have allergic reactions to iodine should notify their doctor and choose an alternative method for testing for epilepsy.

The CAT scan takes x-ray images of the body, in this case the brain, from many different angles. Results are immediately displayed on a computer showing progressive slices of the brain. These slices can be manipulated by the computer to show a 3D model of the patient's brain.

The whole procedure can take from a half hour to longer depending on what the neurologist is looking for. Like a MRI, the machine can be rather claustrophobic however the CAT scan machine tends to be larger than a MRI machine.

CAT scans for epilepsy are low-risk procedures however some patients experience a reaction to the iodine based dye that is injected into the bloodstream. Reactions to the dye include itching, rashes, hives and a feeling of warmth in the body and usually disappear on their own, going away quickly. Anaphylactic reactions are more serious and potentially life threatening. These reactions are much rarer and require immediate medical assistance.

The dyes have caused toxicity to the kidneys in the past. People with impaired kidney function, diabetics and dehydrated individuals were most susceptible to this while undergoing a CAT scan however newer dyes have been developed and have nearly eliminated this complication.

Because radiation is used in CAT scans, pregnant women should discuss the potential risks with her doctor and consider other methods of testing that won't endanger the fetus.