Balance Testing VNG/ENG

Balance testing, or VNG/ENG testing, is a compilation of several tests that measure eye movements to determine if vertigo is caused by central or peripheral pathology. Eye movement is measured using infrared cameras located in goggles worn by the patient during the evaluation. These tests are noninvasive; however, they may induce dizziness.

The vestibular system is comprised of both peripheral and central components. Peripheral components include the visual system, semicircular canals (inner ear), and a sense of muscular movement. Central components (neuronal) are combined with peripheral sensory information in order to help maintain balance.

The goal of a VNG/ENG is to determine whether vertigo or imbalance is due to a peripheral pathology, central pathology, or a combination of the two.

Generally, audiologists are part of a team of specialists who help to diagnose and treat vestibular disorders.


The four primary parts of the VNG test are:

  1. Ocular mobility. This part of the testing tracks rapid eye movements. The audiologist will be watching for slowness or inaccuracies in the eyes’ ability to follow objects.
  2. Optokinetic nystagmus. During this part, the patient will be asked to watch a continuously moving image to see if the eyes can appropriately track the movement.
  3. Positional nystagmus. During this part of the test, the technician will move the patient’s head and body into several different positions to make sure that there are no unexpected resulting eye movements. Inappropriate eye movements can be indicative of a peripheral pathology.
  4. Caloric testing. Finally, the audiologist will stimulate both of the patient’s inner ears with warm and then cold air to make sure that the ears can sense this stimulation. The ear’s response confirms that the vestibular system for each ear is working correctly.
women balancing