Videonystagmography (VNG) is a diagnostic test used to evaluate the vestibular system, which is responsible for maintaining balance and orientation. The test measures eye movements in response to different stimuli to assess the function of the inner ear and associated structures. VNG is a non-invasive, objective test that can provide valuable information about the cause of balance disorders and dizziness.
The test involves wearing a pair of lightweight goggles that contain video cameras and infrared sensors. The goggles record eye movements while the patient performs a series of movements and tasks designed to stimulate the vestibular system. The patient may be asked to follow a moving target with their eyes, turn their head or body in different directions, or stand and walk on different surfaces. The goggles record and analyze eye movements, including the speed, duration, and direction of the movement.
VNG measures several types of eye movements that are associated with different components of the vestibular system. These include:
The results of the VNG test can help diagnose and differentiate between various vestibular disorders. For example, the test can help identify abnormalities in the vestibular system that may be responsible for dizziness or balance problems. The results can also help determine whether the problem is in the inner ear or central nervous system.
VNG can be used to diagnose a range of vestibular disorders, including:
VNG is a safe and non-invasive test that is typically well-tolerated by patients. The test takes approximately 30-60 minutes to complete, and patients may experience mild discomfort or dizziness during the test. The results of the VNG test can be used to develop an individualized treatment plan for the patient, which may include medications, physical therapy, or surgery.
One advantage of VNG over other vestibular tests is its ability to assess eye movements in response to specific stimuli. This allows for a more precise diagnosis and treatment plan. VNG also provides objective, quantitative data that can be used to track changes in vestibular function over time.
One limitation of VNG is that it does not provide information about the cause of vestibular dysfunction. Additional tests, such as magnetic resonance imaging (MRI), may be necessary to identify the underlying cause of the problem. In addition, VNG may not be suitable for patients with certain medical conditions, such as severe neck or back pain, claustrophobia, or other conditions that limit head movement.
