Visual Evoked Potential/Response (VEP/VER)
What is VEP?
Visual Evoked Potential/Response (VEP/VER) measures the electrical signal generated at the visual cortex in response to visual stimulation. The retina, generates electrical signals that are transformed to the visual cortex in the brain, through the optic nerve and optic pathways. The visual cortex is primarily activated by the central visual field and there is a large representation of the macula in the occipital cortex. VEP depends on the integrity of the visual pathway including eye, optic nerve, optic chiasm, optic tract, optic radiation and cerebral cortex.
Why is the test performed?
The Vep test is performed in order to diagnose and follow up on different conditions of the eye. It is used in pathologic conditions of the optic nerve and the visual pathway. It is used to assess the damage of optic nerve and visual pathway from congenital eye disease, trauma, tumors of the brain and optic nerve and autoimmune diseases. It is also used and help diagnose different nervous system conditions like multiple sclerosis and other conditions. It also can be used to asses vision in newborns and toddlers.
How is the test performed?
The test is very simple and fast. In our center we use a special portable device that does not need sedation nor anesthesia. The test takes few minutes to perform each eye. It is noninvasive and no injection is needed. During the test, three electrodes are used. One electrode is attached to forehead, the second to the occipital oz in the back of the skull and the third is attached to the ear lobe. During the test the patient is asked to look inside the ball of the device. The device will then scan your eye without touching it. Scanning takes few seconds.