Electrodiagnostic Testing (NCV)
Nerve Conduction Velocity Testing (NCV) is used to diagnose nerve damage or dysfunction and to confirm a particular diagnosis. It can usually differentiate injury to the nerve fiber (axon) from injury to the myelin sheath surrounding the nerve, which is useful in diagnostic and therapeutic strategies.
How is it performed?
During the test, flat electrodes are placed on the skin at intervals over the nerve that is being examined. A low intensity electric current is introduced to stimulate the nerves.
The velocity at which the resulting electric impulses are transmitted through the nerves is determined when images of the impulses are projected on an oscilloscope or computer screen. If a response is much slower than normal, damage to the myelin sheath is implied. If the nerve’s response to stimulation by the current is decreased but with a relatively normal speed of conduction, damage to the nerve axon is implied. NCV testing is useful in arriving an accurate diagnosis when combined with other diagnostic tests, patients symptoms and clinical testing.
NCV Testing is useful in the diagnosis of:
- Peripheral Neuropathies
- Carpal Tunnel Syndrome
- Tarsal Tunnel Syndrome
- Other nerve aliments