Dizziness and Balance Disorders
- Hearing loss
- Pressure or fullness in your head and ears
- Ringing/buzzing in the ears called tinnitus
Dizziness: A Symptom of Another Disorder
Dizziness can be a symptom of all sorts of disorders. Various disorders and conditions include:
- Vestibular disorders, or problems in the inner ear
- Disorders in the central nervous system, the brainstem or brain
- Cardiovascular problems such as high blood pressure or anemia
- Infection, either baterial or viral
- Reaction to medication
Diagnosing dizziness is a complex process usually requiring several tests. In most cases, you will start with a detailed medical history and a physical examination. The more specific you can be about when your dizziness began, when episodes are most likely to occur and what sensations you experience, the more information your physician will have to develop a diagnosis. The balance system is located primarily in your inner ear, and as such, a hearing test is a common first diagnostic procedure.
The Anatomy Underlying Eye-Movement Testing
Although your balance system is located primarily in the inner ear, it is connected with the brain and brainstem, the eyes, and the sensory nerves throughout your body. Each of these centers send and receive messages to the others, usually permitting you to maintain your balance or, when some disorder is present, causing you to feel abnormal dizziness.
One clearly measurable sign within the balance system is a rapid, involuntary eye movement called nystagmus. By stimulating your nervous system in various ways that stimulate your balance system and then carefully measuring the eye movements, your physician can learn much about any abnormalities in your vestibular system.
Electronystagmography (ENG) Testing
This test battery is called an ENG, short for electronystagmography, the electronic recording of your eye movements, as related to the balance system.
ENG testing is a battery of tests that contribute significantly to the information your doctor needs to diagnose your disorder.
- First is the saccade, testing rapid side-to-side eye movements
- Second is the pursuit test, measuring your ability to follow moving targets
- Third is a positioning maneuver test for motion-induced dizziness
- Fourth is a caloric test that introduces cool air or water and then warm air or water into the ear canal and measuring the resulting changes in eye movement
During ENG tests, electrodes taped near the eyes carefully monitor your eye movements. For some of the tests you will be seated and observing light targets whose movements are precisely planned and controlled to evoke normal or abnormal movements. For other procedures, such as the caloric test, you will be lying down. The entire test sequence usually takes approximately two hours.
Depending on the results of your other tests and your ENG tests, your doctor may arrive at a diagnosis or may require further testing. Once a diagnosis is determined, a range of treatments have been proven as safe and effective in controlling most of the disorders underlying dizziness.
Some conditions can be controlled with medication, others by diet. Some require surgical intervention, others physical therapy and exercise. Whatever your problem, the key to its solution most often lies in careful, sophisticated diagnosis made possible by today's advanced diagnostic instrumentation, and by careful adherence to your physician's treatment plan.