Have a question? Feel free to browse our Frequently Asked Questions listed below. If you don’t see the information you need, please contact us.

Index

VEP and EEG Technology
What is Visual Evoked Potential (VEP)?
What is Electroencephalograph (EEG)?
What is the relationship between VEP & EEG technology?

General Information

What is a Diopsys NOVA-DT VEP Pediatric Vision Test?

It is a painless, safe, non-invasive test to objectively measure neurological responses of the entire visual pathway. It is much more than a common vision test.

How should I prepare for the test?

All medications should be taken as usual unless otherwise directed by the doctor. Hair should be clean, dry, and free of any gels, sprays, or oils.

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.

How is the test done?

The technologist will attach three small sensory pads to your head using a washable gel material. You will be seated in front of a screen and asked to stare at the center. The screen will display different size patterns that quickly reverse. One eye is covered while the other eye is tested. A computer records your response. The test will take between 5 and 20 minutes.

What else do I need to know?

You must sit still during the test. Relaxation is an important part of the test.

What can I expect after the test?

After the test the technologist will remove the sensory pads and use a small amount of water to remove any gel residue. The test results will be given to your doctor.

Questions?

These FAQ’s are not specific to your child but provides general inform. For questions about your child’s test please ask your child’s doctor.

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VEP & EEG Technology

What is Visual Evoked Potential (VEP)?

Visual Evoked Potential is a non-invasive testing method that provides objective information about a child’s vision system. VEP provides a means to measure the complete visual pathway, from the lens to the visual cortex, to detect mechanical or neural abnormalities related to vision. These problems are often subtle and difficult to detect.

The VEP is an electrical signal generated in response to a known visual stimulus. The potential is an electrical response to a stimulus. This testing device uses visual stimuli in a specific pattern to evoke the electrical response, or potential, in the brain. It then measures the potential from the visual pathway of each eye, or both eyes simultaneously and graphically documents the results.

What is Electroencephalograph (EEG)?

The Electroencephalograph (EEG) is a neurological test which measures electrical activity of the brain. To do an EEG a patient has sensory pads applied to various locations on the head. A test device records the electrical signals from these sensory pads and plots the data for evaluation. The EEG can be tailored to evaluate specific functions of the brain.

What is the relationship between VEP and EEG technology?

The VEP is a tailored EEG Test. The VEP is used to test the functionality of the brain’s vision system from the eye to the visual cortex. With the VEP, this external stimulus is a series of patterns displayed on a computer monitor.

The Diopsys NOVA-TR system uses VEP technology with size varying objects held at a constant light level as the stimulus. This system requires only three sensory pads to acquire the data required to assess the patient’s neurological response.

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