A nerve conduction study, also known as nerve conduction velocity (NCV), is a diagnostic tool that measures the speed of an electrical impulse as it travels through a nerve. Neurologists use the test when they want to evaluate nerve function and determine if a patient’s muscle weakness or pain are due to nerve damage or destruction. The physicians at The Neurology Group in Miami typically use nerve conduction velocity as part of an electromyography, a test that evaluates nerve impulses in the muscles. If you suspect you have nerve damage, call the office or book an appointment online today.
During a nerve conduction study, a neurologist places two surface electrodes on your skin over the nerve. One of the electrodes provides a mild electrical impulse, and the other electrode records the response of the nerve. The test is performed for each individual nerve that requires assessment.
To calculate how quickly a nerve transmits an impulse, neurologists measure the distance between the two surface electrodes and the time it takes for the electrical impulse to travel between them.
An nerve conduction study is often performed at the same time as an EMG, or electromyography, which is a test that evaluates the electrical impulses in muscles. An EMG can help diagnose a wide range of muscle disorders, including those that involve nerve disorders. After conducting an EMG and assessing muscle health, a nerve conduction study can be used to reveal specific areas of nerve damage.
Patients who have the following symptoms may need both types of tests:
Electromyography that includes a nerve conduction study can often confirm or rule out a variety of nerve problems and neuromuscular disorders, including:
During your nerve conduction study, you’ll be asked to remove jewelry and any other metal objects, because they can interfere with the test. You may also be asked to wear a hospital gown. Your neurologist at The Neurology Group places the surface electrodes at specific points on your skin. You feel each electrode giving off a constant, mild electrical impulse.
When your doctor stimulates a nerve, you feel something like a mild electrical shock. It may cause you to experience some temporary discomfort during nerve stimulation, but you won’t feel any pain once the procedure has finished.
To ensure the electrodes stay put on your skin during the test, take a shower beforehand to remove the natural oils from your skin, and don’t apply any lotions or creams. If you have a cardiac defibrillator or a pacemaker, let your neurologist know ahead of time.
It’s important for you to have a normal body temperature during the procedure, because a low body temperature slows nerve conduction and affects your results. If you feel cold or are having your test done in the winter, allow extra time so you can warm up after you arrive for your appointment. In the office we can warm your extremities using a heater.