Electronystagmography is defined as the test that is done to look at the voluntary and the involuntary eye movements in a person. It actually helps evaluate the acoustic nerve. This is the nerve that runs from a person's brain to their ears and thus helps to control the hearing and the balance. Also the occulomotor nerve, that runs from the person's brain to their eyes could be examined. The test is also used to help in determining whether balance or a nerve disorder is the cause of dizziness or even of vertigo. The doctor may order the electronystagmography test if the patient has impaired hearing, or even has suspected damage to their inner ear from some medications that were prescribed to them or consumed.
Normal results may indicate the distinct involuntary eye movements that can normally occur after the instillation of some warm or even cold water into the patient's ear canal. Normal value ranges can normally vary a little among different laboratories. Abnormal results can be a sign of some damage to the patient's nerve of their inner ear or any other parts of their brain which controls the eye movements. It could be any disease or any injury that can damage the acoustic nerve and can cause vertigo. It could include a blood vessel disorder with some bleeding or clots, or even atherosclerosis of the patient's blood supply of their ear. It can be related to Cholesteatoma and other ear tumors or congenital disorders or an Injury. There are some medications which are toxic to the patient's ear nerves, including the aminoglycoside antibiotics, a few antimalarial drugs, some loop diuretics, and also salicylates. It even includes multiple sclerosis and movement disorders like progressive supranuclear palsy or Rubella. Some other conditions when the test can be taken include Acoustic neuroma or Benign positional vertigo or Labyrinthitis or Meniere's disease.
There does however, exist a very small risk associated with the electronystagmography test mainly during the caloric stimulation part of this particular test. If there is an excessive water pressure then it can injure an already damaged eardrum which has actually been perforated in the recent past due to the risk of causing an ear infection. Some alternative names for this electronystagmography test include ENG. There is very minimal discomfort. Some may find the cold water in one's ear uncomfortable. The patient may experience brief dizziness while this test is being conducted.
Submitted by M T on April 1, 2010 at 06:05