A visual evoked potential test (VEP) is used to look for problems in the brain or nerves that affect vision. A machine records brain waves related to the nerves that make up the visual pathway.
This test is often used to:
There are many symptoms that might lead your doctor to order a VEP. You may be having double vision, blurred vision, or loss of part or all of your vision.
There are no major complications associated with this procedure.
You will be given instructions to prepare for the test, such as:
Wires will be attached to your scalp with tape. A patch will be placed over one eye. You will watch a screen with your other eye. The process is then repeated with the opposite eye covered.
The wires will be removed from your head.
You will be able to leave after the test is done.
About 45 minutes
Your doctor will discuss the results with you and any further treatment that may be needed.
Call your doctor if you have any concerns.
If you think you have an emergency, call for emergency medical services right away.
National Eye Institute (NEI)
National Multiple Sclerosis Society
Canadian Association of Optometrists
Canadian Ophthalmological Society
Evoked potentials (EP). National Multiple Sclerosis Society website. Available at: http://www.nationalmssociety.org/Symptoms-Diagnosis/Diagnosing-Tools/Evoked-Potentials. Accessed May 16, 2016.
Evoked potentials studies. Johns Hopkins Medicine website. Available at: http://www.hopkinsmedicine.org/healthlibrary/test_procedures/neurological/evoked_potentials_studies_92,P07658. Accessed May 16, 2016.
Visually evoked potentials. Webvision website. Available at: http://webvision.med.utah.edu/book/electrophysiology/visually-evoked-potentials. Updated July 14, 2015. Accessed May 16, 2016.
Last reviewed May 2018 by Michael Woods, MD Last Updated: 5/16/2016