• Introduction
• Anatomy
• Maintenance of Balance
• Causes of Dizziness
• Diagnosing the Cause of Dizziness
• Common Types of Dizziness
• Medical Treatment of Dizziness
• Surgical Treatment of Dizziness
• Risks and Complication of Surgery for Dizziness
• Summary

Dizziness is a general term for many different symptoms. While it generally means an abnormal sensation of motion, it can also mean imbalance, lightheadedness, blacking out, staggering, disorientation, weakness, and other sensations. The symptoms can range from mild and brief to severe spinning sensations accompanied by nausea, also known as vertigo.

Dizziness:

General term for all abnormal symptoms of balance and stability

Imbalance:

Inability to keep one's balance, especially when standing or walking

Lightheadedness:

The feeling of nearly passing out, similar to the feeling you might get if you hold your breath for a long time.

Vertigo:

The sensation that you or your surroundings are moving or spinning or whirling.

The ability to keep one's balance is a complicated interaction between many different organs and systems in the body. The brain is the central processing center for all balance information coming from the senses and for all information going out to the muscles of balance. Input comes from three main areas: vision, the balance portion of the inner ear, and the touch (from the feet and joints). Vision is an important cue to the brain, which tells us if we are moving relative to our surroundings.

There are two parts of hearing: mechanical and nerve (or electrical). The mechanical part picks up sound from the outer ear canal and then vibrates the ear drum and three tiny hearing bones in the middle ear. The inner ear looks a bit like a snail. It has two halves which are connected and are filled with fluid. The coil or cochlea takes care the nerve part of hearing. Like a telephone, it takes the vibration and turns it into an electric signal that is relayed to the brain.

The other half of the inner ear is the balance or vestibular system. There are three balance canals, each set in a different direction. Depending on which way you turn fluid moves within the canals and sends the direction to the brain by way of the vestibular nerve. The inner ear fluid undergoes a natural recycling everyday. It is made from the brain's spinal fluid and is absorbed by the endolymphatic sac. In Meniere's disease, the sac fails to absorb enough fluid. This increases inner ear pressure resulting in dizziness and hearing loss.

Also, in close association with the ear is the facial nerve. It helps move the face and also provides for some of the taste to the tip of the tongue.

Balance is maintained by the interactions in the brain of nerve impulses from the inner ear, the eye, the neck muscles, and the muscles and joints of the limbs. A disturbance in any of these areas may result in the subjective sensation of dizziness or unsteadiness. General disturbances of body function may lead to dizziness by interfering with coordination of the impulses in the brain.

The brain, reacting to abnormal or uncoordinated impulses, may respond in such a way that the individual has false feeling of movement (dizziness), resulting in staggering or falling. The brain's influence on the body's glands and muscles may result in the individuals breaking out in a cold sweat, along with nausea or vomiting.

According to the National Institute of Health, the senses are also important in determining balance. Sensory input form the eyes as well as from the muscles and joints is sent to the brain, alerting us that the path we are following bends the right or that our head is tilted as we bend to pick up a dime. The brain interprets this information - along with cues from the vestibular system and adjusts the muscles so that balance is maintained. Dizziness can occur when sensory information is distorted. Some people feel dizzy at great heights, for instance, partly because they cannot focus on nearby objects to stabilize themselves. When one is on the ground, it is normal to sway slightly while standing. A person maintains balance by adjusting to the body's position to something close by. When someone is standing high up, however, objects are too far away to use to adjust balance. The result may be confusion, insecurity, and dizziness, which is sometimes resolved by sitting down.

Some scientist believe that motion sickness, a malady that affects sea, car and even space travelers, occurs when the brain receives conflicting sensory information about the body's motion and position. For example, when someone reads while riding in a car, the inner ear senses the movement of the vehicle, but the eye gazes steadily on the book that is not moving. The resulting sensory conflict may lead to the typical symptoms of motion sickness: dizziness, nausea, vomiting, and seating.

Another form of dizziness occurs when we turn in a circle quickly several times and then stop suddenly. Turning moves the endolymph. The moving endolymph tells us we are still rotating but other senses say we have stopped, therefore, we feel dizzy.

Dizziness can be grouped into types by the portion of the entire balance system that is not working properly. The different portions include the inner ear, the brain, the eyes, and the limbs (neck, back, and leg muscles and joints which react to keep us upright).

Half of the inner ear is used for hearing (the cochlea) and the other half is used for balance (the labyrinth). If the labyrinth or the nerve that connects it to the brain is malfunctioning, dizziness can result. Many types of maladies occur in the inner ear to cause dizziness, including Meniere's disease, labyrithitis, positional vertigo, and vestibular neuritis and tumors of the inner ear nerves. These usually cause imbalance, vertigo (spinning), and nausea. It can also be accompanied by tinnitus and hearing loss, if the nearby cochlea is also affected. These diseases will be further explained later.

Central dizziness is caused by problems in the balance portion of the brain. Anytime this portion of the brain is not working properly, dizziness can occur. Symptoms usually include lightheadedness, disorientation, imbalance, and sometimes even blacking out. Causes of central dizziness include low blood sugar, low blood pressure to the brain, strokes, multiple sclerosis, migraine headaches, head injury, tumors, and the aging process, among others. Treating these types of dizziness usual involves treating the problem which is causing the brain not to work properly.

This type of dizziness is uncommon. If the muscles, joints or touch sensors of the limbs are not working well, it becomes difficult for the body to react to motion, and makes it difficult to remain upright. Causes of muscle-joint dizziness include muscular dystrophy, severe diabetes, arthritis, joint replacements, and injuries. Symptoms are usually imbalance and unsteadiness.

Eye muscle imbalance and poor vision can make one's balance worse. The brain relies on information from the eyes to help with balance. Carsickness or seasickness are types of visual dizziness because the eyes are constantly adjusting to a moving visual field, and confuses the balance part of the brain. This can lead to dizziness, nausea, and vomiting.

Dizziness can be caused by numerous disturbances to any of many different parts of the body. Based upon your history and physical findings, your physician may require further tests to complete a full evaluation. The test necessary are determined at the time of examination, and may include hearing and balance tests, x-rays (CT or MRI scans), blood tests, and ultrasound tests. A general physical exam and neurological tests may also be needed.

The most common test for dizziness is the ENG, or electronystagmogram. In this test, the strength of inner ear is tested, as well as the coordination of eye movements. It involves watching eye movements after placing warm or cool air into the ear canal. This usually causes a normal sensation of brief dizziness. It is important not to be taking any medications which can effect the test, such as valium, Antivert, alcohol, and others. When scheduling this test, make sure to ask if your medications are OK.

Transcranial Doppler is another test for specific types of vascular dizziness. It is a safe, quick way of looking at the change in blood flow to the balance centers of the brain. It uses soundwaves, much like a ultrasound looks at babies in a mother's womb.

The object of this evaluation is to be certain that there is no serious or life threatening disease, and to pinpoint the exact site of the problem. This lays the groundwork for effective medical or surgical treatment.

Diagnosis can often be difficult. Frequently, multiple tests must be conducted. Patience and understanding is necessary on the part of the doctor and patient alike. This will lay the groundwork for effective medical or surgical treatment.

BPPV is the most common type of dizziness. In BPPV, you experience vertigo, usually when changing head position, such as in rolling over in bed or tilting the head backwards or forwards. BPPV is caused by tiny bone fragments or crystals floating in the inner ear fluid, which causes the sensation of spinning. The most common causes of BPPV are trauma to the head or viral infections of the inner ear, but it may start without any apparent cause.

Treatment of BPPV is usually an office repositioning maneuver, that places the crystals in an area that does not cause dizziness. If they stay motionless for 48 hours they will often resorb or stick in place. Keeping the head upright assists this. Following repositioning, certain head exercises can help decrease symptoms. Repositioning may need to be done on multiple occasions.

If the repositioning maneuver is ineffective, surgery may be required, such as posterior canal occlusion. (see below)

Neuritis (inflammation of a nerve), usually due to a virus, may affect the balance (or vestibular) nerve. When this happens the balance centers of the brain are overstimulated which results in severe dizziness and vertigo. Fortunately, vestibular neuritis usually subsides in time and usually does not recur. Certain medications can help in the initial phases to decrease the severe symptoms, and later, balance exercises (vestibular rehabilitation) can speed recovery. Surgery is occasionally needed if symptoms persist.

Meniere's Disease is a disorder of the inner ear cause by excess pressure in the endolymphatic fluid compartment. The pressure is usually caused by excess inner ear sodium (salt).In addition to dizziness, which usually lasts hours, patients may have fluctuating hearing, tinnitus, and a feeling of fullness in the affected ear. It can occasionally affect both ears.

The cause of this disorder is not known. The spells can sometimes be induced by excess salt intake, stress, weather changes, or allergies.

Treatment usually includes restriction of salt (sodium) intake and the use of a diuretic (water pill). Sometimes, anti-dizziness medications like Antivert or Valium can decrease the severity of the spells - but they do not cure the disease. Steroids can occasionally help but because of side-effects, their use must be limited. If your doctor recommends water pills or steroids for you, please ask our nurses for our instruction sheets to better inform you of their side-effects - and check with your family doctor.

In severe cases of Meniere's Disease, surgery may be needed. Fortunately, there are many surgical options (listed below). But of all these options, only Sac Decompression surgery attempts to improve function of the inner ear. The remaining options attempt to selectively ablate (remove or destroy) the malfunctioning balance nerve, and sometimes, the hearing nerve, as well.

The proper function of the balance system requires not only the input for the inner ear, but also the appropriate nerve connections in the brain. If the areas of the brain that assist in balance do not get enough blood, even temporarily, dizziness can occur.

Causes of vascular dizziness are varied. Arthritis in the neck can cause compression of arteries to the head, and cholesterol plaques may narrow the arteries also, causing decreased blood flow. Often, blood pressure to the brain can drop temporarily when standing up quickly, especially in people on blood pressure medication or older patients. Special test such as MRI or Doppler tests may be needed to accurately diagnose these problems.

The inner ear is a fluid filled space within the bone of the skull. If a leak of fluid from this space occurs, dizziness and hearing loss may occur. The leak usually occurs in or near the natural structures of the inner ear, such as the Oval and Round membranous windows. The leak may occur naturally, with heavy straining, or after trauma. Some children may be born with an abnormal connection between their brain and their ear, a so called "Enlarged Vestibular Aqueduct". This can sometimes be detected on CAT scan and can lead to fluctuating hearing loss as well as dizziness. Inner earleaks may heal on their own with rest. In some cases, minor surgery is required to plug the leak.

Rarely, tumors can be a cause of dizziness. The most common types are not cancerous. Acoustic Neuromas are benign tumors of the balance nerve. They can cause unsteadiness, hearing loss, and tinnitus. Surgery is the most effective treatment.

Meniere's disease can often be improved by decreasing inner ear pressure. This is usually done by decrease the amount of sodium in the inner ear. A very low salt (sodium) diet combined with a water pill (diuretic) which eliminates sodium from the body is usually very effective. If you take water pills, make sure to have blood tests to assure your potassium does not get too low. Steroids can occasionally help but they may have many side-effects. Make sure to discuss them with your doctor.

To assist the body's ability to compensate to a balance loss, certain exercises can speed recovery. These exercises, found at the end of the booklet, can strengthen the balance system, and thereby decrease symptoms. These exercises will benefit almost all patients with any type of dizziness.

For Meniere's disease and a few other uncommon ear disorders, "Transtympanic Injections" of medications may be of some benefit. These medications can include steroids to decrease inflammation, or medications, like gentamicin, which has special effects on the inner ear. Gentamicin has been used as a way of destroying the inner ear without surgery. In progressive treatments, it can destroy the balance portion of the inner ear, leading to fewer dizzy spells. Gentamicin treatments require several visits in which the medication is placed through a small hole created in the ear drum. Careful monitoring is necessary regarding the amount of medication used because the best dose for each person can vary greatly. However, these treatments can lead to unsteadiness and hearing loss. Thus, these treatments are more often recommended for the elderly or those who already have a significant hearing loss. Also, there is small risk that the intentional perforation of the ear drum will not heal or may become infected.

Surgery may be needed to treat dizziness, if medical treatment fails. Several types of operations are available, depending on the cause of the dizziness. Not all procedures are options for every patient. Some can only be offered in severe situations.

You and your doctor will need to decide on which therapy is best for you. This is always a matter of weighing the pro's and con's of each option whether it is medical or surgical. Factors include the patients hearing, age, health and the severity of disease.

Surgical risks vary according to the procedure and by a person's age and health. Most inner ear operations require a general anesthetic and an incision behind the ear after shaving a small amount of hair. Any surgery in or around the ear can put at risk many of the structures that reside in this area.

Therefore, risks typically include hearing loss, tinnitus, dizziness, infection and bleeding. Because of the close relationship of the facial nerve, face weakness or taste disturbances are possible.

Surgery performed adjacent to the brain adds additional risks to life, brain and the surrounding nerves. In order to prevent a leakage of spinal fluid, patients who undergo clipping of the balance nerve often have a small amount of belly fat taken as a graft to seal the area underneath the incision.

In Meniere's diseases, the inner ear is under excess pressure. One portion of the inner ear, called the endolymphatic sac, is surrounded by bone. By removing the bone surrounding this area, pressure in the inner ear may be reduced, greatly improving symptoms of Meniere's disease. Inner ear fluid undergoes a natural recycling everyday. It is made from the brain's spinal fluid and is absorbed by the endolymphatic sac. In Meniere's disease, the sac fails to absorb enough fluid. This increases inner ear pressure resulting in dizziness, tinnitus and hearing loss. In the past, a small tube was placed into the sac to drain fluid, but we have found that the surgery is just as successful without a tube and has less chance of hearing loss. Since it is found partially imbedded in bone in between the ear and the thick lining of the brain, a very slight risk of spinal fluid leak is possible. Although it is successful for most patients, few patients may not notice drastic changes. It is a procedure that has a low risk of hearing loss, so is usually recommend as the first choice for surgically treating Meniere's disease.

When dizziness is severe, but hearing is still good, cutting the balance nerve between the inner ear and the brain is very effective in eliminating vertigo, while preserving hearing. This procedure requires general anesthesia and 4 to 5 days hospitalization. Since access to this area is through a craniotomy, hair must be shaved for several inches behind the ear, and small piece of fat from the belly area must be harvested to place into the incision to decrease the chance of spinal fluid leak. There is always some vertigo following the surgery which resolves after several days of compensation. Although the dizzy attacks are usually completely eliminated, there may be persistent unsteadiness. Usually, the opposite inner ear will compensate for this but a balance exercise program is essential. .Occasionally, some people may get headaches following the surgery. As with any craniotomy, there is a small risk of infection (meningitis), leak of spinal fluid, or headaches.

If a patient has useful hearing, then there is a choice between the nerve clipping operation (vestibular nerve section) or an endolymphatic sac decompression.

The sac operation is a more minor procedure the goal of which is to relieve pressure within the inner ear rather than removing the balance function as cutting the nerve does. Although it is not as effective as vestibular nerve section, it avoids many potential risks because it is not necessary to work within the brain's cavity. Furthermore, it is the only surgery that may actually improve hearing in some patients - especially if it is done early in the course of the disease.

Trying to decide between these two operations is a common problem. The nerve clipping operation is one of the most successful treatments for Meniere's disease but there are surgical risks related to working along the nerve's root at the brainstem. Also, after cutting one balance nerve, it takes awhile for the other ear to take over. Head exercises are important to help overcome unsteadiness.

Unfortunately, Meniere's disease can sometimes affect not one but both ears. In that case, we are reluctant to cut either balance nerve, so a sac decompression is preferred.

This procedure is only performed for severe cases of Benign Position Vertigo (BPPV). In this procedure, the portion of the inner ear which is causing the dizziness is blocked off, by plugging its canal with tissue or bone. This prevents the abnormal motion of inner ear crystals; it is very effective in relieving vertigo and has a very low risk of hearing loss.

In patients with a perilymph fistula, the inner ear fluid leak may need to be patched. The eardrum is lifted and the likely areas of leakage are patched with tissue from behind the ear. Often the leak is microscopic, so the likely areas of leakage are patched, even if no fluid is seen. Symptoms usually improve over the next several weeks.

In severe cases of dizziness, labyrinthectomy can eliminate symptoms by removing the inner ear structures. However, it results in complete loss of hearing in the operated ear. It is very successful in stopping dizzy spells. However, the surgery results in total loss of hearing in the operated ear, and therefore is generally performed when there is already poor hearing in that ear. Following the surgery, there is usually a period of several days of dizziness which resolves. Although the dizzy attack are usually completely eliminated, there may be persistent unsteadiness. Usually, the opposite inner ear will compensate for this but a balance exercise program is essential.

Further hearing impairment is the operated ear may occur following any of the procedures and is always expected following labyrinthectomy. Perforation of the ear drum can cause some hearing loss.

Tinnitus (head noise) usually remains the same as before surgery. If the hearing is worse following surgery, tinnitus may likewise be more noticeable.

Taste disturbances and mouth dryness are not uncommon for a few weeks following surgery. In some instances this disturbance is prolonged.

The facial nerve travels through the ear bone in close association with the hearing and balance nerves, the inner ear and the mastoid. Temporary weakness of one side of the face is an uncommon postoperative complication of ear surgery. It may occur as the result of an abnormality or a swelling of the nerve. Permanent paralysis of the face is extremely rare. Should it occur, however, eye complications could develop, requiring treatment by an eye specialist.

Some of the operations described above result in a temporary leak of spinal fluid (fluid surrounding the brain). This leak is always closed prior to the completion of the surgery. On occasion, however, the leak reopens and further surgery may be required to stop it.

Infection is a rare occurrence following dizziness surgery. Should it develop, however, it could lead to meningitis (an infection in the spinal fluid) and might require IV antibiotics. Fortunately, this complication is very rare.

Certain procedures can cause permanent destruction of the inner ear function. This usually eliminates dizzy spells, but may lead to chronic imbalance problems. Usually this is improved with physical therapy, but may be permanent. It is also common with dizzy problems caused by both ears. Labyrinthectomy, vestibular nerve section, and gentamicin treatments almost always have at least a someperiod of time when imbalance occurs.

A hematoma (collection of blood under the skin incision) develops in a very small percentage of cases, prolonging hospitalization and healing. Reoperation to remove the clot may be necessary if this occurs.

For vestibular neurectomies, a craniotomy (openeingopening the skull) is required. Although unlikely, leakage of spinal fluid is possible, however it is minimized by placing a plug of belly fat into the area. Also, there is a slight risk of long term headaches (which can be treated with anti-inflammatory medications). Other very rare complications could include meningitis, bleeding, stroke, or even loss of life.

Make sure to ask your doctor how soon you may return to work or driving after surgery. This will vary based on the severity of your dizziness, your job and the type of surgery. It may range from days to many weeks. Stuffiness and hearing loss can be expected for some time with any ear operation. This will usually improve slowly as your body absorbs the healing fluids.

Fortunately, most types of dizziness can be cured or at least improved. But in some cases, no medical or surgical treatment may be effective. If so, patients will need to learn how to adapt to a chronic problem. Diet, rehabilitation and exercise can all be important as can developing a positive attitude. As noted above, antidepressants are sometimes very effective, not only to help with the anxiety and depression commonly associated with persistent dizziness, but also because these medications can actually help the inner ear and brain's chemicals (neurotransmitters). These medications should be supervised by your family doctor.