Electronistagmography & bull; hello healthy

Definition

What is electronistagmography?

Electronistagmography (ENG) is a method used by doctors to examine eye movements and nystagmus, the uncontrolled rhythmic movements of the eye resulting from small, fast, uncontrolled tremors. This procedure will also check the eye movement muscles. ENG will test how well the eyes, inner ear, and brain are in helping to coordinate your balance (such as when you get up after lying down).

ENG is performed to help check for possible injury or problems to the inner ear, brain, or the nerves that connect the two. This disorder can result in complaints of dizziness, vertigo, or loss of balance.

Nystagmus usually occurs when the head is moved. However, if nystagmus occurs all the time and doesn't go away, it may be caused by some condition that affects the inner ear, brain, or the nerves that connect the two.

During the ENG procedure, a number of electrodes will be attached to the area around the eye to record eye movements. This movement will be reflected on the graph paper. There may be several tests.

When should I undergo electronistagmography?

ENG is performed if you report complaints of unexplained periods of dizziness, vertigo, or hearing loss. Other conditions that make this procedure possible are acoustic neuroma, labyrinthitis, Usher's syndrome, and Menier's disease. If a lesion is detected, ENG can identify its initial location.

There may be other reasons for your doctor to recommend ENG.

Precautions & warnings

What should I know before undergoing electronistagmography?

In some clinics, you cannot perform ENG if you are using a pacemaker, because the electronystagmography device will affect the performance of the pacemaker. ENG cannot detect some problems in the inner ear, a normal test result does not mean there is no interference with the inner ear. To check for the cause of hearing loss or tinnitus, other tests such as audiometric tests or auditory brain stem response (ABR) may be performed. If a tumor or stroke is suspected in certain parts of your brain, a CT scan or MRI may be done to confirm the diagnosis.

Process

What should I do before undergoing electronistagmography?

Tell me about all the medicines you are taking, including blood thinners such as warfariin, clopidigrel, and aspirin. You may be advised to fast a few hours before the procedure and caffeine or alcohol for 24 - 48 hours leading up to the ENG procedure. Your doctor may also advise you to temporarily stop using sedatives, anesthetics, or anti-vertigo medications before the procedure. The morning before the procedure, clean the ears of excess wax. If you use hearing aids or glasses, take them to the test room with you.

You may be required to sign a consent letter before undergoing the procedure.

How is the process of electronistagmography?

Five electrodes will be attached to the area around the eye using a special glue. You will be examined in a dark room during the procedure. ENG consists of 6 parts:

1. In order to set the tester to the correct setting, you will have to watch the laser dot move. Don't move your head while doing this part.
2. The reading will be carried out blindfolded. You will be given tasks to do, such as mental arithmetic, during this part. The reading will be taken as you look straight ahead and both sides.
3. The reading will be taken as your eye follows the back and forth of the pendulum
4. The reading will be made when your eyes follow the movement of several objects that move outside your line of sight. Every time an object passes by, you will have to immediately focus on the next object's movement.
5. The reading will be made as you move your head from side to side, and tilt your head up and down. You will be asked to move your body (along with your head) in several positions.
6. Towards the end of the procedure, eye movements will be recorded while cold water and warm water are placed in your ear. In certain cases, cold and warm air will be blown into your ears. This part of the test is called a caloric test, and it can be done without electrodes placed on your face. The caloric test will not be done if you have a perforated eardrum, because the water used can get into the middle ear and put you at risk of infection. The caloric test can be done with water or air, but if the eardrum is perforated, the doctor will not do this test at all.

The duration of this examination ranges from 60 - 90 minutes.

What should I do after undergoing electronistagmography?

When the test is complete, the electrodes will be removed and any residual glue that had stuck to your face will be removed. Do not rub your eyes to avoid spreading the electrode glue. You will be checked for signs of pain, dizziness, and nausea, and may need to lie down or sit for a while to wait to recover. Your doctor will explain to you when you will be allowed to continue other medications that were stopped before the procedure. Depending on your condition, your doctor will provide special or additional instructions after the procedure.

Explanation of the Test Results

What do my test results mean?

Normal result

No abnormal eye movements were found during the procedure. Keep in mind that some nystagmus is normal when you move your head.

Caloric test results are said to be normal if uncontrolled eye movements have normal direction and intensity.

Abnormal results

Wild nystagmus was detected that occurred over time and did not go away. Caloric test results are said to be abnormal if there is little to no eye movement during the procedure.

Abnormal results can:

• find damage to nerves or structures near the ear or brain that affect balance coordination
• detect possible signs of Ménière's disease, multiple sclerosis, or labyrinthitis, or disease of the brain or a history of stroke

What can affect the test?

Reasons you cannot follow the ENG procedure or the test results are said to be not credible, including:

• taking some medications, such as stimulants (including caffeine), depressants, sedatives, and drugs for vertigo
• too much head or other eye movements, such as blinking
• unable to complete instructions during the test. Health conditions that can affect focus, blurred vision, or cause drowsiness
• find damage to nerves or structures near the ear or brain that affect balance coordination
• detect possible signs of Ménière's disease, multiple sclerosis, or labyrinthitis, or disease of the brain or a history of stroke