Reply To: E.N.G
I believe you are referring to Electromyogram (EMG). However, it is a Nerve Conduction Velocity Study (NCS or NVS) that may be most beneficial in diagnosing CIDP/GBS.
Conduction/velocity studies are tests that measure how well individual nerves can send an electrical signal from the spinal cord to the muscles. Nerve conduction studies are often used to help diagnose nerve disorders, such as carpal tunnel syndrome or Guillain-Barré syndrome.
During a nerve conduction test, a health professional places a shock-emitting electrode directly over the nerve to be studied, and a recording electrode over the muscles supplied by that nerve. The shock-emitting electrode sends repeated, brief electrical pulses to the nerve, and the recording electrode records the time it takes for the muscle to contract in response to the electrical pulse.
Diagnostic uses for nerve conduction studies include:
• Detecting and evaluating damage to the peripheral nervous system, which includes all the nerves that lead away from the brain and spinal cord and the smaller nerves that branch out from those nerves.
• Identifying the cause of abnormal sensations, such as numbness, tingling, or pain.
The electrodes often penetrate the skin and can be briefly painful. Sometimes I had a little bleeding following being poked. If one is on blood thinners (Coumadin, etc) the technician needs to be made aware of it. Ask your doctor if you can take a pain reliever (Tylenol, etc) in advance of the study to minimize discomfort. Wear loose fitting clothing; you may be given a hospital gown to wear anyway. Since electrodes will be placed on your skin, make sure the surface is clean and free of lotions and oils that might interfere with results. Ice the area after the tests to help reduce any discomfort.