Diagnostic Tests

Advances in technology have helped doctors understand how the brain works and what happens when the brain is injured. The following tests are often used when a child has a brain injury.

CT or CAT Scan (computerized axial tomography)

This special type of x-ray uses a computer to give detailed pictures. A CT scan of the brain helps identify the location and extent of brain injury. It shows areas of hemorrhage, fluid collection, or swelling inside the brain. Often a CT scan of the brain is repeated several times to watch for changes.

MRI (magnetic resonance imaging)

Like a CT scan, an MRI uses a computer to produce a very clear, two-dimensional picture. An MRI uses magnetic fields to produce the picture. An MRI may reveal subtle injuries to the brain or spinal cord that cannot be seen on regular x-rays or even CT scans.

EEG (electroencephalogram)

An EEG records electrical activity of the brain. It uses electrodes which look like small flat sponges with wires attached. These are placed onto the scalp and connected to a machine which records electrical activity. An EEG can tell if brain activity is normal or not, and it helps identify and locate areas in the brain causing a seizure.

Evoked Response Test

An evoked response test, or evoked potential test, is a special type of EEG. In children who are unconscious, evoked response testing may help determine their potential to see, hear, or feel. This testing determines if connections between the brain and sensory organs like the eyes, ears, and skin have been affected. However, the child's actual ability to see, hear, or feel can not really be known until the child is alert. There are several types of evoked tests:

* VER (Visually Evoked Response) uses checkerboard pictures or flashing lights and electrodes to test the child's ability for sight.

* BAER (Brainstem Auditory Evoked Responses) uses clicking noises and electrodes to test the child's ability for hearing.

* SEP (Somatosensory Evoked Potential) uses small electrical currents and electrodes to test the child's ability to feel the environment.