Frequently Asked Questions about Visual Electrophysiology and Eye Diseases
[/vc_column_text][vc_column_text]These FAQs are provided for general information. For questions about Diopsys® ERG or VEP vision tests, please ask the eye care specialist in charge of your vision care.[/vc_column_text][/vc_column][/vc_row][vc_row full_width=”stretch_row” el_class=”faq-index-row” el_id=”faqs”][vc_column width=”1/2″][vc_column_text]General Information
What is a Diopsys® ERG vision test?
What is a Diopsys® ffERG vision test?
What is a Diopsys® VEP vision test?
Are these vision tests covered by my insurance?
Will this replace any other eye tests I take?
How should I prepare for the test?
Should I bring my glasses or contacts if I do not wear them regularly?
Can my family member be present during testing?
Will I be dilated for my ERG or VEP vision test?
What can I expect after the test?
[/vc_column_text][/vc_column][vc_column width=”1/2″][vc_column_text]Eye and Vision Disorders
What is glaucoma? What causes glaucoma?
Signs and Symptoms of Glaucoma
Signs and Symptoms of Diabetic Retinopathy
Signs and Symptoms of Cataracts
What is multiple sclerosis (MS)?
Signs and Symptoms of Multiple Sclerosis
What is traumatic brain injury (TBI)?
Signs and Symptoms of Traumatic Brain Injury
[/vc_column_text][/vc_column][/vc_row][vc_row full_width=”stretch_row_content_no_spaces”][vc_column][vc_single_image image=”188″ img_size=”full” alignment=”center”][/vc_column][/vc_row][vc_row el_id=”ergvisiontest” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]What is a Diopsys® ERG vision test? A Diopsys® ERG vision test is a painless, safe, non-invasive way for your eye care provider to objectively measure the function of your retina – the light-sensitive layer at the back of your eye. When light from an image enters your eye, it is turned into electrical energy by cells in the retina. Pattern ERG, or electroretinography, uses visual stimuli from a computer screen in different patterns and contrasts to elicit that electrical response. The electrical energy created is measured by the Diopsys® ERG vision test, and used to create a report for your doctor. It is similar to an EKG, but for your eyes. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”ffergvisiontest” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]What is a Diopsys® ffERG vision test? A Diopsys® ffERG vision test is a painless, safe, non-invasive way for your eye care provider to objectively measure the function of cells in your retina – the light-sensitive layer at the back of your eye. When light from an image enters your eye, it is turned into electrical energy by cells in the retina. The full field electroretinography (ffERG) vision test, sometimes referred to as flash ERG or flicker ERG, uses flashes of light as a visual stimulus to elicit an electrical response from those cells. The electrical energy created is measured by the Diopsys® ffERG vision test, and used to create a report for your doctor. It is similar to an EKG, but for your eyes. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”vepvisiontest” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]What is a Diopsys® VEP vision test? A Diopsys® VEP vision test is a painless, safe, non-invasive way for your eye care provider to objectively measure the function of your entire vision system. When light from an image enters your eye, it is turned into electrical energy by cells in the retina – the light-sensitive layer at the back of your eye. These cells send the electrical energy back to the visual cortex, the part of your brain where the image is processed. VEP, or Visual Evoked Potential, uses visual stimuli from a computer screen in different patterns and contrasts to elicit the electrical response from your retina. The electrical energy is then sent to your visual cortex, where the Diopsys® VEP vision test records the electrical signal, and creates a report for your doctor. It is similar to an EKG, but for your entire vision system. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”whichtest” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Which test will I need? Your test will be ordered by your ophthalmologist or optometrist prior to your appointment. The type of test you need will be determined by the vision disorder that your doctor suspects. It is possible that multiple tests may be ordered on the same day or at separate visits. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”covered” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Are these vision tests covered by my insurance? Many insurance policies do cover these tests, as they are accepted as an additional, alternative testing method when more in-depth measures of visual function are required for diagnosis, treatment and management of disorders that affect vision. Your eye doctor’s office can help to verify coverage by your insurance plan. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”replaceother” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Will this replace any other eye tests I take? No. Other tests such as the Visual Field and OCT may still be performed. Electroretinography and visual evoked potential provide a different view into your overall eye health. The more information your doctors have, the better they can direct your care. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”whoperforms” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Who will perform the test? The test is typically performed by an ophthalmic technician. Diopsys Clinical Application Specialists train and certify technicians to perform the tests safely, accurately, and in a timely manner. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”howlong” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]How long does the test take? The test itself does not take long. However, there is some preparation involved in order to get quality test results. To get a more accurate time frame, Diopsys recommends you contact your doctor’s office directly. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”howprepare” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]How should I prepare for the test? All medications should be taken as usual unless otherwise directed by your doctor. Hair should be clean, dry, and free of any gels, sprays, or oils. We also recommend that you do not wear ponytails or braids to the appointment as they may need to be taken down. It is important that you feel relaxed and comfortable so the test results are accurate. For young children, it may be helpful to bring a favorite item such as a blanket, pacifier, or toy that will make them feel more comfortable. Smaller children may also sit in their parent’s lap during testing if this is calming for them. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”howperformed” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]How is the test performed? Each test uses three (3) small sensors for testing. The placement and type of sensor depends on the test ordered by your doctor. The technician will attach the small sensory pads to your face and/or head using a washable gel material. For Diopsys® ERG and Diopsys® VEP vision tests, you will be seated in front of a computer screen and asked to look at the center of the monitor. The screen will display different size patterns that appear to “flip” quickly. One eye may be covered while the other eye is tested. A computer records your response. For Diopsys® ffERG vision tests, you will be handed a small dome, and asked to cover your right eye. Lights will flash in the dome during the test, and half way through, you’ll be asked to switch to your left eye. A computer records your response. To watch a brief video of setup and testing, please click on the links for Diopsys® ERG, Diopsys® ffERG, or Diopsys® VEP. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”bringcorrection” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Should I bring my glasses or contacts if I do not wear them regularly? It is always recommended that you bring your eyewear. Depending on your refraction and ordered test, they may be helpful for your technician to have. If needed, the technician may have you wear a trial frame and lenses during the test. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”family” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Can my family member be present during testing? It is important for you to be relaxed and able to focus during the test. It is for this reason that we request family members wait outside the testing room. For young children, they may sit in their parent’s lap during testing if this is calming for them. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”dilated” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]Will I be dilated for my ERG or VEP vision test? Dilation is not indicated prior to pattern or full field (flicker) electroretinography, nor visual evoked potential vision testing. Dilation is required for multifocal ERG (mfERG) vision testing. Your doctor may decide to dilate your eyes after testing for other reasons. Your doctor’s office can tell you if dilation will be done during your appointment. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”aftertest” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]What can I expect after the test? The technician will remove the sensory pads and use a small amount of water to remove any gel residue. The ERG and/or VEP test results will then be read and interpreted by your ophthalmologist or optometrist. [/vc_column_text][/vc_column][/vc_row][vc_row el_id=”whatelse” el_class=”faq-answer”][vc_column el_class=”faq-answer”][vc_column_text el_class=”faq-answer clearfix”]What else do I need to know?- You must sit still as relaxation is an important part of testing.
- If you wear makeup, we suggest that you do not apply it prior to your visit. If you must wear makeup to your visit, you may want to bring it with you to touch up after testing. The technician must remove some makeup to ensure proper sensor connection to your skin.
- Supplies provided by Diopsys for testing are latex free, hypo-allergenic, and water soluble. If you have specific topical allergies, please consult your doctor prior to testing.
- Seizure disorders are contraindicated for VEP, ERG, mfERG and ffERG vision testing.
- People who are pregnant or wear a pace-maker are safe to be tested. However, we suggest you consult your doctor prior to testing.
- Please advise your doctor of any new eye complaints prior to testing. Severe seasonal allergies or certain ocular surface disorders can leave the eye dry, itchy and irritated, which can affect your ability to test.
- Diopsys kindly requests that you turn off your cell phone prior to testing to avoid any interruptions during these important vision tests.
