Visual Evoked Potential

*Play the video below to watch an example a Diopsys® VEP vision test.*Visual Evoked Potential (VEP) Vision Testing

Visual evoked potential (VEP) is a highly-advanced vision test that
objectively measures how well your entire vision system is working. The
results of this VEP vision test will help your doctor diagnose various
vision disorders, and better understand when changes in your visual
function occur.
What is a visual evoked potential (VEP) vision test?

The Diopsys® VEP vision test is a painless, safe, non-invasive way for your
eye care provider to objectively measure the function of your entire vision
system.

When light from an image enters your eye, it is turned into electrical
energy by cells in the retina – the light-sensitive layer at the back of
your eye. These cells send the electrical energy back to the visual cortex,
the part of your brain where the image is processed.

VEP, or Visual Evoked Potential, uses visual stimuli from a computer screen
in different patterns and contrasts to elicit the electrical response from
your retina. The electrical energy is then sent to your visual cortex,
where the Diopsys® VEP vision test records the electrical signal, and
creates a report for your doctor. It is similar to an EKG, but for your
entire vision system.
How do I prepare for the VEP test?

Your face and hair should be clean, dry, and free of any gels, sprays,
oils, makeup, or lotion.
How is the Diopsys® VEP vision test done?

A technician will clean and dry three small areas on your head, and then
place sensory pads on the cleansed areas.

The technician will ask you to cover one eye at a time while the VEP vision
test is being run.

Once the test begins, you will see black and white patterns that appear to
“flip” quickly over and over again on a computer screen. You will be asked
to focus on the pattern during the test. The computer will record the
electrical energy that reaches the visual processing center of your brain
and produce a report for your doctor.