Visual Nystagmography (VNG)
VNG testing is a series of tests assessing balance (vestibular) function by recording a person’s ability to follow visual objects with their eyes and how well the eyes respond to information from the vestibular system.
To monitor the movements of the eyes, infrared goggles are are worn by the patient with the purpose of recording eye movements during testing. VNG testing is non-invasive, and only minor discomfort is felt by the patients during testing as a result of wearing goggles. VNG consists of three components:
Ocular-Motor Evaluation: This part of the test evaluates eye movements and the central nervous system. You will be asked to follow a green dot on a large monitor during different tasks for 10-15 minutes.
Positional Evaluation: This part of the test evaluates both your central nervous system and the balance organs of your inner ear. You will be asked to sit, lie down and turn your head to the left and to the right.
Caloric Evaluation: This part of the test evaluates the function of the balance organs of the inner ear. During the test, you will be lying comfortably on your back while wearing the capped goggles. Cool air, followed by warm air will be introduced into each ear canal for approximately 1 minute at a time. The change in the temperature of the ear canal will induce some dizziness. It is important to remember that while you may feel dizzy during this test, you should feel better by the time you leave.