What is “Nerve Conduction Velocity?” (NCV)
Nerve conduction velocity (NCV) is a test to see how fast electrical signals move through a nerve.
How the test is performed.
Patches called surface electrodes, similar to those used for ECG, are placed on the skin over nerves at various locations. Each patch gives off a very mild electrical impulse, which stimulates the nerve.
The nerve’s resulting electrical activity is recorded by the other electrodes. The distance between electrodes and the time it takes for electrical impulses to travel between electrodes are used to determine the speed of the nerve signals.
Electromyography (recording from needles placed into the muscles) is often done at the same time as this test.
How should you prepare for the tests?
- Please inform the physician if you are taking any blood thinners (Plavix, Coumadin, aspirin, etc.), or if you have a pace-maker implanted or have been diagnosed with a bleeding disorder
- Bathe or shower before the test to remove extra oil from the skin
- Avoid applying body lotions or skin oils on the day of the test
How long do the tests take?
- Between 20 and 90 minutes depending on whether you are getting an EMG alone or an EMG combined with NCV.
- You can do any of your normal activities like eating, driving and/or exercising before and immediately after the tests.
- There are no lasting side effects of any of these tests.
