**Visual Evoked Potential (VEP) test** also known as **nerve eye tape** is a non-invasive test that helps doctors diagnose certain symptoms that affect the way the eyes and brain function. Examples of this test being used to diagnose symptoms of Multiple Sclerosis (MS), brain, head or brain injury.. Discuss and explain how it is done.. Article Related: What is the auditory evoked potential test?... What is the optic nerve strip?.. Using the eye strip test, it is possible to measure and evaluate the electrical signals that the visual cortex (an area of the brain) produces in response to visual stimulation.. This is also called the visual evoked potential (VEP) test.. The VEP test evaluates the function of the visual pathway, which includes: - Eyes - Optic nerves - Optic chiasm (a place in the brain where the optic nerve fibers coming from one eye pass between the nerve fibers of the other eye.) - visual system (the path between the visual chiasm and the brain) - optic radiation (part of the visual pathway that transmits visual input from the retina, optic nerve and optic canal) .... - meninges Any abnormality affecting the visual pathways or the visual cortex of the brain can show up as an abnormality in the VEP test. When is VEP used?. Some problems in the path of certain nerves can cause changes in vision. In these cases, the doctor may recommend an optic nerve tape test. Some of these symptoms may include the following: - Loss of vision - double vision - Blurred vision - Flashing light - Change in seeing colors - Weakness in the eyes, arms or legs These changes are often very subtle or not easily detected by a doctor during a clinical examination.... In general, the VEP test is useful for diagnosing problems with the optic nerve, so the nerve allows us to transmit signals to the optic nerve.. To see how the visual system reacts to light.. This test can be used to check vision in children and adults who are unable to read eye charts.. - Multiple sclerosis (MS), which often causes optic neuritis.. MS is the most common reason a doctor may recommend a visual evoked potential test. slow.. - Glioma on the optic nerve (usually due to neurofibromatosis type 1.) - Compression of visual pathways, such as hydrocephalus or pituitary adenoma - Damage to the visual pathway related to head or brain trauma - Toxic optic neuropathy caused by some drugs or other toxins such as carbon monoxide - Other types of optic neuropathy, such as anterior ischemic optic neuropathy - Vision problems due to infections such as meningitis VEPs can also help doctors assess the progress of certain neurological diseases that have already been diagnosed. Examples of these diseases include: - Multiple sclerosis (MS) - Leber's optic neuropathy (LON) - Predominant optic neuritis (DON) - Friedrich's ataxia How is VEP optic nerve tape done? The optic nerve strip test involves electrodes being placed on specific areas of the scalp while the person views a visual stimulus (usually a flashing checkerboard pattern)...the electrodes record electrical activity in the brain....neurologists perform VEP tests in the background of an electroencephalogram (EEG)...a device that captures the evoked potential of EEG signals following multiple visual stimuli to assess pathway function Sight averages.. An evoked potential device records the electrical response to visual stimulation in multiple channels or traces.. Stimulus... which can indicate various issues in your visual pathway.... How to prepare for an optic nerve tape test?... Your doctor will give you adequate information about what to expect during the test and what to do beforehand, as well as instructions to prepare for the study.... Before doing the test you need to make sure your hair is clean and free of any hair sprays, oils or gels... Can these products interfere with possible electrodes during the test? Different types of VEP tests, so the process may vary. In general, you can expect the following: 1... a medical professional places electrodes (small metal discs) with removable adhesive on specific places on your scalp... 2... the electrodes are connected to a machine that gives the operator information about brain activity... 3... you place a patch over one eye and look at a flashing visual stimulus (usually a checkerboard pattern) played on a monitor... 4... when the test is repeated for the other eye. What information does the optic nerve tape result contain?.. Using the visual evoked potential test, several different problems can be detected in the visual pathway... Each subject has a different presentation in terms of the waveform and duration between the stimulus and the brain activity... For example, in the condition of nerve demyelination Vision (as in MS), VEP testing shows delayed brain responses... Complications of visual evoked potential testing This procedure rarely has side effects... The visual evoked potential test is painless and, apart from minor skin irritation, often has no complications... If you have a condition such as epilepsy, visual stimuli to which you are exposed are unlikely to cause seizure activity... However, you should consult your doctor before performing a VEP test... Getting... VEP testing in the brain and nerve center The visual evoked potential (VEP) test is performed by a neurologist at Neurali Neurology Center with the best and latest equipment...