What is VNG testing?
The Videonystagmography (VNG) is a test of your balance system. The test records nystagmus (quick eye jerks) by a camera. There are neural connections that stretch from the balance mechanism in the inner ear to the muscles of the eye. A disorder of the balance mechanism results in small eye jerks that can only be detected by a sophisticated computer. A camera attached to a pair of goggles that the patient wears records these eye jerks during a series of tasks.
The balance mechanism is monitored during tasks that consist of looking back and forth between designated points, following moving lights, lying in different positions, shaking your head, and lying down and sitting up quickly.
The final portion of the test requires putting cool and warm air in the ear canal for roughly 60 seconds in order to determine if the balance mechanism of each ear can increase and decrease normally in response to stimulation.
Because the hearing and balance functions of your inner ear are closely related, a hearing test will be administered prior to the VNG if not recently performed.
10Important Instructions For VNG Testing
Certain medications and alcoholic beverages can influence the body’s response to the test, altering the results of the test; therefore, it is important to observe the following:
- Certain medications must be avoided for 48 hours before the test, including: sleeping pills, diuretics, tranquilizers, sedatives, antihistamines, muscle relaxants, anti-dizzy medications, barbiturates, anti-depressants, anti-anxiety medications, pain medication. **Please do not discontinue prescription medications without checking with the physician who prescribed them. If you cannot go without a medication listed above, please call the audiologist to discuss this prior to arriving for the evaluation.
- No alcohol for 48 hours before the test.
- No food or beverages (except water) for 3 hours before the test.
- No smoking for 3 hours before the test.
- Females – no eye make-up of any sort (no eyeliner or mascara, especially) should be worn to the test.
- Please dress comfortably. Women may wish to wear slacks.
What should I expect?
This test will likely cause some dizziness, however, this generally passes within a few minutes. It is advisable that you make arrangements for someone to be available to drive you home in the event of prolonged dizziness. In most circumstances, the test will be interpreted and you will see the doctor shortly after the test procedure. This test takes approximately 60-90 minutes to administer.