What does electronystagmography test for?
Electronystagmography is used to evaluate unexplained dizziness, vertigo or hearing loss.
Electronystagmography (ENG) is a test that evaluates involuntary (not under conscious control) movements of the eyes (nystagmus). It is generally advised if you have unexplained dizziness, vertigo or hearing loss.
The physician may ask for an ENG if you have the symptoms of vertigo, which include
ENG may help the physician find the exact cause of your symptoms. Some of the most common causes of these symptoms include
- Acoustic neuroma (tumor of the nerve that controls sound and balance)
- Labyrinthitis (inflammation of the inner ear)
- Usher syndrome (a congenital disorder that leads to hearing loss)
- Meniere disease (a condition where there is an excessive fluid in the inner ear affecting hearing and balance)
- Benign paroxysmal positional vertigo (sudden sensation of spinning with episodes of dizziness associated with head movements)
- Vestibular neuronitis (sudden severe attack of vertigo)
- Perilymph fistula (tear in either one of the membranes separating your middle and inner ear)
ENG also helps determine the actual location of the lesion.
What is electronystagmography?
Electronystagmography (ENG) is used to assess vertigo and other hearing and vision disorders. Vertigo is a false sense of spinning motion or motion that can cause dizziness. Electrodes used in ENG are placed above and below the eye to record electrical activity. ENG is a series of tests that may include one or more of the following measurements
- Calibration test: In this test, you follow a light with your eyes. Calibration tests help to detect ocular dysmetria, which is a condition that causes under- or over-shooting of the eye when you try to fix your gaze on an object.
- Pendulum-tracking test: In this test, the eyes move like a clock pendulum while following light.
- Gaze nystagmus test: In this test, you gaze at a fixed light placed to either the center or the side as you are seated or lying down. This test measures how well you can fix your gaze on an object without your eyes moving involuntarily.
- Positional test: In this test, you may have to move your head, perhaps your whole body, as opposed to just your eyes.
- Optokinetic test: This test checks your ability to follow a light as it moves quickly across and out of your field of vision and back again while you keep your head still.
- Water caloric test: This test places warm or cool water into the ear canal with a syringe. As the water touches the eardrum, the eyes will move involuntarily in response to the stimulus in the absence of any disorders.
What does the result of electronystagmography mean?
Electronystagmography (ENG) is excellent for identifying inner ear disorders. If ENG diagnoses the exact type of vertigo, the physician may suggest physical therapy, surgery or medications for balance-related disorders.
If ENG fails to identify the exact cause of vertigo, the doctor may suggest other tests such as rotational chair testing, fistula tests or magnetic resonance imaging (MRI).
