A VEP (Visual Evoked Potential) is a neurology test that examines the abnormalities and damage in the optical path from the eyes to the occipital lobe of the brain, which may cause specific visual problems. It is helpful for doctors to detect various kinds of vision disorders, and to understand the changes in visual functions. This test is also known as the VER (Visual Evoked Response) test.
Why is a Visual Evoked Potential (VEP) Test done?
The doctor usually recommends a VEP test, when you start experiencing changes in your eyesight that can be due to abnormalities/ problems along the routes of specific nerves.
You may experience the following symptoms:
- Painful or painless Loss of eyesight
- Duplicate or Blurred vision
- Vision impairment
- Flashing lights
- Changes in colour vision
- Weakness in eyes, legs or arms
What is the procedure for the Visual Evoked Potential (VEP) test?
- The technologist measures the head of the patient and then marks the positions of an electrode with a non-toxic and washable marker.
- The technologist will rub the positions with an exfoliating cream and apply four electrodes using a conductive cream and cotton balls.
- The technologist will then test the eyesight of the patient.
- Wear glasses or contacts lenses during the exam, if you have
- The technologist will then turn off the lights
- You will be asked to focus on a dot in the middle of a black and white checkerboard screen that moves back and forth for the best results.
- Once the results of both eyes are stored and printed correctly, the test is complete.
How does one prepare for the Visual Evoked Potential (VEP) test?
- Bring your glasses or contact lenses to wear during the test.
- Keep your hair and face clean and dry on the day of the test.
- Don’t use hair gel, hair sprays, hair oils, makeup or lotion on the day of the test
- Inform the Technologist/ radiologist/doctor about the medication you are taking.
No special care is required for the test.
Cost of Visual Evoked Potential (VEP) Test?
The cost of the Visual Evoked Potential (VEP) test ranges from INR 2000 to INR 4000.