Computed tomography, also known as a CT scan, combines x-rays and computer technology to produce rapid, clear, two-dimensional images of organs, bones, and tissues. Occasionally a contrast dye is injected into the bloodstream to highlight the different tissues in the brain and to detect signs of encephalitis. CT scans can also detect bone and blood vessel irregularities, certain brain tumors and cysts, herniated discs, spinal stenosis (narrowing of the spinal canal), blood clots or intracranial bleeding in patients with stroke, brain damage from a head injury, and other disorders.
Magnetic resonance imaging (MRI) uses computer-generated radio waves and a strong magnet to produce detailed images of body structures, including tissues, organs, bones, and nerves. The pictures, which are clearer than those produced by CT, can help identify brain and spinal cord inflammation, infection, tumors, eye disease, and blood vessel irregularities that may lead to stroke. A contrast dye may be injected prior to the test to reveal more detail.
Electroencephalography, or EEG, can identify abnormal brain waves by monitoring electrical activity in the brain through the skull. Among its many functions, EEG is used to help diagnose:
- Certain seizure disorders
- Brain damage from head injuries
- Specific viral infections such as herpes virus
- Inflammation of the brain and/or spinal cord.
This painless, risk-free test can be performed in a doctor's office or at a hospital or testing facility.