Nerve conduction velocity

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Nerve conduction test

Overview

Risks

Results

Nerve conduction velocity

Definition:

Nerve conduction velocity (NCV) is a test of the speed of conduction of impulses through a nerve.

Alternative Names:

NCV

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 NCV test.

How to prepare for the test:

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

Infants and children:

The preparation you can provide for this test depends on your child's age and experience. For general information regarding how you can prepare your child, see the following topics:

Infant test or procedure preparation (birth to 1 year)
Toddler test or procedure preparation (1 to 3 years)
Preschooler test or procedure preparation (3 to 6 years)
Schoolage test or procedure preparation (6 to 12 years)
Adolescent test or procedure preparation (12 to 18 years)

How the test will feel:

The impulse may feel like an electric shock. Depending on how strong the stimulus is, you will feel it to varying degrees, and it may be uncomfortable you. You should feel no pain once the test is finished.

Often the nerve conduction test is followed by electromyography (EMG) which involves needles being placed into the muscle and you contracting that muscle. This can be uncomfortable during the test, and you may feel muscle soreness at the site of the needles afterwards as well.

Why the test is performed:

This test is used to diagnose nerve damage or destruction.

Review Date: 4/28/2005
Reviewed By: Chitra R. Uppaluri, M.D., Clinical Assistant Professor of Medicine, Saint Louis University, St. Louis, MO. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2004 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.