Nerve Conduction Study


In this test, several flat metal-disc electrodes are attached to your skin with tape or a paste. An electrode that puts out electric pulses is placed right over the nerve. Then a recording electrode is placed over the muscles controlled by that nerve. Several quick electrical pulses are given to the nerve. The time it takes for the muscle to contract in response to the electrical pulse is recorded. The speed of the response is called the conduction velocity.
The same nerves on the other side of the body may be studied. The results from both sides of the body can be compared. When the test is done, the electrodes are removed.
Nerve conduction studies are done before an EMG if both tests are being done. Nerve conduction tests may take from 15 minutes to 1 hour or more. How long the tests take depends on how many nerves and muscles are studied.

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