Abnormal visually evoked potential [VEP]

This code indicates an abnormal result from a visually evoked potential (VEP) study. A VEP measures the electrical signals generated by the brain in response to visual stimuli, assessing the integrity of the visual pathway from the retina to the occipital cortex. An abnormal VEP suggests dysfunction in this pathway.

Use this code when diagnostic testing, specifically a VEP, reveals an abnormal response. This often occurs in patients presenting with unexplained vision loss, suspected optic nerve disorders (e.g., optic neuritis, multiple sclerosis), or other neurological conditions affecting visual processing. Documentation should clearly state the VEP results as abnormal.

• This code is for the finding of an abnormal VEP, not the VEP procedure itself.
• Always code the underlying condition or definitive diagnosis if known and documented, as the abnormal VEP may be a symptom.
• Do not confuse with codes for abnormal electroretinogram (ERG) or other electrophysiological studies of the eye.