What is Evoked Potential (EP) Testing?

Evoked Potential (EP) testing is used to check the condition of nerve pathways. A healthy nervous system uses electrical energy to carry messages smoothly along nerve cells to the brain. EP tests quickly and safely measure the electrical signals carried by the nerves.

What do these tests show?

EP testing helps diagnose disorders of the nervous system, locate the site of nerve damage, and evaluate your condition after treatment or during surgery. In many cases, EP testing allow for an early diagnosis and more effective treatment.

Who performs the testing?

A qualified neurologist supervises the testing and interprets the results. A technologist may perform the test.

What happens during EP testing?

A mild stimulus is applied repeatedly to the eyes, ears, or limbs. The stimulus is what causes the nerves to react and send a message to the brain. Small metal discs (electrodes) on the skin's surface record how the brain and spinal cord respond to the stimulus. A computer analyzes the responses and displays them on a screen as a waveform. The waveform may also be printed on paper. Patterns in the waveform help reveal or rule out certain problems. The wave patterns also help show where any damage is along the nerve pathway.

When will the results of my EP testing be available?

The results are typically available within three to five days. These results will be sent to your personal physician, who will make a diagnosis based upon the neurologist's interpretation.