Janet Revelle, AuD, Director of the Bacharach Hearing and Balance Center explains why someone with vertigo would need a VNG test. “It is,” she says, “simply the Gold Standard.”
For individuals having difficulties with their balance and equilibrium, videonystagmography (VNG) is a valuable diagnostic procedure. It is simple and painless, and it can help more accurately determine the cause of dizziness symptoms.
“Vertigo or dizziness is a symptom, not a disorder,” says Dr. Revelle. “Just like a headache can be a symptom of many different conditions or even a combination of conditions. There are many possible underlying causes for vertigo, and a VNG is a vital component of the diagnostic process.”
The hearing and equilibrium systems share the same fluids and nerve pathways to the brain. They are located in the inner ear. That is why a comprehensive audiologic evaluation is performed along with the VNG study. It helps to identify any asymmetry which may not be detected in everyday listening. The difference between ears can point to an inner ear problem.
What Does a VNG Test Reveal?
The VNG evaluation does three things. It tests the visual pathways to the brain, it evaluates the function of the equilibrium system in each inner ear, and it provides information of how these systems work together for the body to be “in balance.”
During the VNG evaluation, patients wear special goggles. The goggles use infrared cameras that track and record their eye movements. Specific eye movements are measured in response to the stimuli during the test. These movements reflect the functionality of these systems.
When Might a VNG Test Be Indicated?
Dr. Revelle noted some instances where a VNG test was indicated. “A person with a concussion, suspected Lyme disease or MS with dizziness or imbalance, may be referred for VNG testing”, she said. “The results can indicate or identify the underlying issue, whether it is due to a central/neurological condition or inner ear disorder. This helps us develop a recommended treatment plan. Sometimes the treatment is vestibular rehabilitation with a physical therapist or it may be medical treatment and the patient will be referred back to the managing physician.”
It is also common for a person with vertigo to be referred directly for physical therapy. There are specific conditions which are the result of is misplaced “crystals” in the inner ear, which stimulate the equilibrium systems in response to quick head or body movements. A functional physical therapy evaluation can identify these conditions and often correct the condition quickly with specialized maneuvers. Strengthening techniques are also included to reduce the possibility of fall risk.