Diagnostic tests overview

What are some diagnostic tests for nervous system disorders?

Evaluating and diagnosing damage to the nervous system is complicated and complex. Many of the same symptoms occur in different combinations among the different disorders. To further complicate the diagnostic process, many disorders do not have definitive causes, markers, or tests.

Neurological tests to evaluate children may include:

• Computed tomography scan (Also called a CT or CAT scan) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called "slices"), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays. 
• Electroencephalogram (EEG) - a procedure that records the brain's continuous, electrical activity by means of electrodes attached to the scalp.
• Magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.
• Electrodiagnostic tests (i.e., electromyography and nerve conduction velocity) - studies that evaluate and diagnose disorders of the muscles and motor neurons. Electrodes are inserted into the muscle, or placed on the skin overlying a muscle or muscle group, and electrical activity and muscle response are recorded.

• Positron emission tomography (PET) scan - a computer-based imaging technique that provides a picture of the brain's activity rather than its structure by measuring levels of injected glucose which are labeled with a radioactive tracer.
• Arteriogram (Also called angiogram) - a procedure that provides a scan of arteries going to and through the brain.
• Cerebral spinal fluid analysis (Also called spinal tap or lumbar puncture) - a procedure used to make an evaluation or diagnosis by examining the fluid withdrawn from the spinal column.
• Evoked potentials - procedures that record the brain's electrical response to visual, auditory, and sensory stimuli.
• Myelogram - a procedure that uses dye injected into the spinal canal to make the structure clearly visible on x-rays.
• Ultrasound (Also called sonography) - a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.
• Neurosonography - a procedure that uses ultra high-frequency sound waves that enable the physician to analyze blood flow.

How should I prepare my child for neurological testing?

• Infants - You cannot explain the examination to an infant, but you can help your baby feel more secure during the test by bringing a special blanket, toy, or pacifier. You may breastfeed your baby or give him/her a bottle of juice or formula once the technician tells you your baby can eat.
• Toddlers and preschool-aged children - Young children remember things for only a short time, so the best time to talk about the test is right before you are ready to come to the hospital. Explain to your child that you are going to the hospital to have some pictures taken that the physician needs in order to help him/her get better. Try to use simple words.
  It is important to be honest with your child. If the test will be uncomfortable, be sure to talk about and tell him/her it is okay to cry. Because children at this age are afraid of being separated from their parent, let him/her know that mom or dad will stay with him/her as much as possible. When you come to the hospital, bring a favorite book, toy, or blanket.
• School-aged children - School-aged children have good imaginations. If you do not tell them the truth, they may imagine something much worse than the actual test. The day of the test, tell your child that he/she will be going to the hospital to have some pictures taken. Tell him/her that the pictures will help the physician decide how to make him/her better. Use simple words. Be honest. Try to tell your child exactly what will happen. If your child's test is going to be uncomfortable, be sure to tell him/her it is okay to cry. When you come to the hospital, bring along a favorite book, toy, or game.