brain, spinal cord, and nerve disorders
Tests for Brain, Spinal Cord, and Nerve Disorders
Other Tests for Brain, Spinal Cord, and Nerve Disorders
Occasionally, doctors cannot determine the cause of the nerve damage or muscle weakness based on results of blood tests, imaging tests, electromyography (EMG), or nerve conduction studies. In such cases, doctors typically refer the person to a specialist, who may remove a small sample of muscle tissue and/or a nerve to examine under a microscope (biopsy). The sample is removed from an area of the body where symptoms occur. The sample is stained to help doctors identify the pattern of muscle or nerve damage and to determine whether white blood cells (which indicate inflammation) are present. Often, the sensory nerve examination and EMG do not detect damage of the nerves that sense pain or that automatically regulate body processes (called ). Doctors may suspect such damage if people have less sensitivity to pain, have burning pain in their feet, feel dizzy or light-headed when they stand up, or sweat too much or too little. To check for this damage, doctors may use a small round cutter to remove a sample of skin (punch skin biopsy) and send it to a laboratory to be examined under a microscope. If the nerve endings in the skin sample have been destroyed, the cause may be a disorder (such as Overview of Vasculitis ) that affects small nerve fibers, including pain-sensing and autonomic nerves fibers. Echoencephalography uses ultrasound waves to produce an image of the brain. This simple, painless, and relatively inexpensive procedure can be used in children younger than 2 years because their skull is thin enough for ultrasound waves to pass through. It can be done quickly at the bedside to detect Hydrocephalus (previously called water on the brain) or bleeding. CT and MRI have largely replaced echoencephalography in older children and adults because they produce much better images in these age groups. Genetic abnormalities cause many neurologic disorders—particularly Overview of Movement Disorders , including those that cause tremor or problems walking. Genetic tests can sometimes help doctors diagnose certain nerve and muscle disorders. When genetic testing is recommended, people are usually referred to a genetic counselor. If they are not, people may request an appointment with one. 