Dizziness & ENG/VNG Testing
Dizziness is a symptom, not a disease. It is defined as a sensation of unsteadiness, imbalance, or disorientation in relation to an individual’s surroundings. Someone experiencing dizziness might describe it as feeling lightheaded, unsteady, giddy, or having a floating sensation. Feeling dizzy can be caused by many factors, some of which are listed in the chart below.
|Causes of Dizziness|
|Circulation||If your brain does not get enough blood flow, you feel lightheaded. If the inner ear fails to receive enough blood flow, the more specific type of dizziness – vertigo – occurs.|
|Neurological diseases||A number of diseases of the nerves can affect balance, such as multiple sclerosis, syphilis, tumors, etc. These are uncommon causes, but your doctor may perform certain tests to evaluate these.|
|Anxiety||Anxiety can be a cause of dizziness and lightheadedness.|
|Vertigo||An unpleasant sensation of the world rotating, usually associated with nausea and vomiting. Vertigo usually is due to an issue with the inner ear.|
When investigating dizziness, an ENT Specialists provider will do a thorough examination reviewing your symptoms of dizziness along with your general health. Routine tests are performed to check your blood pressure, nerve and balance function, and hearing. Possible additional tests may include a CT or MRI scan of your head, ENG or VNG testing, and in some cases, a cardiology evaluation. Your physician will determine the best treatment for you based on your condition.
Diagnostic testing for Dizziness
Electronystagmopraphy (ENG) and Videonystagmography (VNG) are two tests used by ENT Specialists to test dizziness or loss of balance. These tests evaluate both the central and peripheral aspects of your overall balance system.
ENG means electrical recording of nystagmus, a specific type of eye movement. This testing is performed by using electrodes that are placed around the eyes. VNG is a similar test with the added enhancement of video recordings. This testing is through the use of video goggles placed over your eyes. Both tests record eye movements, providing our specialists with information about your brains ability to coordinate balance signals, react to changes in position, and determine the function of your inner ear. Since our eyes and ears depend on each other for balance and clear vison, these diagnostic tests are great tools to stimulate the inner ear in a controlled way to measure any involuntary eye movement.
Four Part testing of ENG and VNG testing
During the four stages of testing, eye movements are recorded and displayed them on a computer screen. The examiner may ask the patient to perform some mental tasks during the test, such as counting backward or thinking of names. These activities keep the mind busy and alert so that valid test results are obtained.
2010 American Academy of Otolaryngology – Head and Neck Surgery. For more information, visit www.entnet.org or consult with your ENT Specialists physician.