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Ency. home > Test > N > Nerve conduction velocity

Nerve conduction velocity   

Overview | Risks | Results

Alternative names:

NCV

Definition:

An NCV is a test of the speed of conduction of impulses through a nerve.

How the Test is Performed

The nerve is stimulated, usually with surface electrodes, which are patch-like electrodes (similar to those used for ECG) placed on the skin over the nerve at various locations. One electrode stimulates the nerve with a very mild electrical impulse.

The 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 calculate the nerve conduction velocity.

Electromyography is often done at the same time as the nerve conduction velocity (NCV) test.

How to Prepare for the Test

Normal body temperature must be maintained (low body temperature slows nerve conduction).

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

How the Test will Feel

The impulse given may feel like an electric shock. Depending on how strong the stimulus is, the patient will feel it to varying degrees. It may be uncomfortable for some patients (though only during the actual test and there should be no residual pain once the test is finished).

Often the nerve conduction test is followed by an EMG (electromyography) which involves needles being placed into the muscle and the patient being asked to contract that muscle. This can be uncomfortable during the test, and muscle soreness at the site of the needles may be experienced subsequently as well.

Why the Test is Performed

This test is used to diagnose nerve damage or destruction.

Ency. home > Test > N > Nerve conduction velocity

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