When you arrive, please follow the signs to Electrophysiology on the first floor and report to the reception desk in the department.
When you look at something, an image of the object is projected onto the retina at the back of your eye. The retina converts this optical image into very small electrical signals, which pass along the optic nerve to the brain, where the sensation of ‘seeing’ occurs. Visual electrophysiology measures these very small signals produced by the eye and the brain.
Your consultant has asked us to examine the function of your visual system. This is usually to help diagnose the cause of your visual problem. The tests are also used to monitor disease or the effects of any treatment you may be receiving.
The tests are non-invasive and do NOT involve injections.
To perform the tests
When you attend you will have a selection of the tests over the page, depending on the reason for referral:
Dilating drops will cause blurred vision and increased sensitivity to bright light/sunlight, but this will wear off after a few hours. Dark glasses may help on a sunny day.
You should NOT drive for several hours after the testing has finished, until the effects of the eye drops have worn off.
The results of the tests will be analysed, and a report will be sent to the consultant who referred you for testing.
This leaflet is intended to provide general information for patients. If you require further information or advice, please contact the electrophysiology department:
Author: Andrew Carter, Technical Manager
Review date: October 2026