A Visual Evoked Potential (VEP) is a test to help the eye doctor evaluate the vision of a patient who is too young to read the eye chart or who cannot communicate. In some cases, a VEP is used on adults to evaluate or diagnose vision problems.

During the Test

We will clean five to seven spots on your head where we place electrodes for the test. We will then place cupped electrodes filled with a thick lotion on your head. These electrodes will connect to a computer which will record the brain waves. The test is not painful. We will wash off the lotion after the test, but it may leave the hair looking greasy until washed.

Pediatric patients will view a screen that has thick black and white stripes that slowly become thinner until they can no longer be seen.

Adult patients will view moving black and white checks (checkerboard pattern) on the screen.

The computer looks at the brain waves and understands what stripe width or checkerboard pattern was the smallest seen. It will tell us the patient’s visual acuity score (e.g., 20/20, 20/100, etc.). One pediatric VEP measurement takes about ten seconds. We will take multiple measurements of each and both eyes together to get the best results. Total testing time takes about 15 minutes. The adult VEP testing will last about thirty minutes.

Who to Call

University Station Eye Clinic Triage Line

(608) 263-7171

The toll-free number is 1-800-323-8942.
Ask to be transferred to the above number.