The balance organ is part of the inner ear, although the sense of balance actually comes from the coordination of three different body senses: the balance organ in the inner ear, the visual system and the muscles and joints in the body. Dizziness is what happens when there is a deficit in any of these three senses or the brain centers that tie them all together. Because of the complex system that keeps you balanced, dizziness can actually come in many different forms—as a sensation of unsteadiness, spinning or general disorientation in relation to an individual’s surroundings. Dizziness, therefore, is a symptom of a larger problem rather than a disease.
Inner ear causes of dizziness
Dizziness related to the inner ear is one of the most common types and it results from disturbances in the blood circulation or fluid pressure in the inner ear, pressure on the balance nerve or physiologic changes in the balance nerve. Any of these interruptions to the function of the inner ear may result symptoms like tinnitus (ringing in the ears) or hearing loss as well as dizziness.
This dizziness caused by the inner ear may feel like a whirling or spinning sensation (vertigo), unsteadiness or lightheadedness and it may be constant or intermittent. It may be aggravated by certain head motions or sudden positional changes. Although nausea and vomiting may occur, one does not lose consciousness as a result of inner ear dizziness. The pattern of the symptoms experienced will depend on which functions of the inner ear are affected.
Other causes of dizziness
There are many other causes of dizziness which are not related to the function of the inner ear. If the brain is not able to coordinate the inputs from the three parts of the balance system, there is central dizziness. Central dizziness may be caused by migraines, tumors, infections and degenerative diseases like multiple sclerosis. Visual dizziness can occur if the eye muscles are imbalanced or there are errors of refraction, such as when you borrow a pair of eyeglasses from a friend with a different prescription. Other causes of visual dizziness include intermittent inability to focus the eyes, difficulty reading or intermittent blurring of vision. Very rarely, dizzy symptoms may be caused by muscle or joint issues, such as unsteadiness due to muscular dystrophy. General health problems, such as diabetes, thyroid deficiency, vitamin deficiency, anemia and arterial blockage can cause dizziness as well.
Because the inner ear is the most common cause of dizziness, the first place to start with an evaluation is often a hearing test. The cochlea, our hearing organ, is contained within the same bony structure as the balance organ. A behavioral hearing test in a sound booth may be followed by an Auditory Brainstem Response (ABR) test. An ABR test non-invasively records brainstem responses to sound stimuli. The brain waves are collected while you rest comfortably with your eyes closed. The presence or absence of hearing loss or auditory brainstem anomalies will provide clues to the physician about the cause of your symptoms.
Another common test for balance is VNG, or videonystagmography. Usually performed by an ENT physician or an audiologist, a VNG test uses video cameras to record eye movements while a patient tracks a visual stimulus, is moved into different positions and while the ear canals are stimulated with warm and cool air or water. This test gives a broad picture of whether the underlying issue is related to the inner ear or not.
Other tests to evaluate dizziness may be performed by a physical therapist, cardiologist or neurologist. As there are many systems involved in balance, there are many possible underlying causes for dizziness and many medical specialties that may be involved. A very common cause of dizziness that is often overlooked is the interaction of multiple prescription and/or over-the-counter medications. If you have recently changed or added a prescription to your daily routine, be sure to ask your physician about the possibility of dizziness as a side-effect.
Treatments for dizziness
When the cause of the dizziness is determined and treated, the symptom will often go away. For BPPV, dizziness can be treated by a head positioning maneuver. In the case of medical conditions, like allergies, thyroid deficiency and diabetes, regulation of the condition will eliminate the dizziness. Many disorders can be treated with medication, surgery, diet, lifestyle changes or some combination of these. There are also physical therapists who specialize in vestibular rehabilitation, which is a treatment for balance disorders that gradually retrains the brain to compensate for lost sensory input from the balance system. For extreme cases, surgery may be warranted or a suppressant such as Valium may be prescribed to relieve the symptom.
When to get help
When part of your balance system is afflicted, the other parts can usually compensate for the deficit. Once the system is taxed, that compensation may fall short. For example, if you must take an ototoxic drug that destroys the balance organs of the inner ear, you can still stay quite balanced as long as your eyes are open. However, when you are asked to close your eyes, you may find it quite difficult to stay standing upright. Even though your body will work to compensate the immediate loss, don’t wait to seek help. If you experience any dizziness symptoms, you should talk to your physician or a hearing healthcare professional immediately so the underlying cause can be determined and the problem remediated.
- Understanding Vestibular Disorders, Vestibular Disorders Association, http://vestibular.org/
- Dizziness, Mayo Clinic, http://www.mayoclinic.org/diseases-conditions/dizziness/basics/definition/con-20023004