Vestibular Dysfunction

What is Vestibular Dysfunction?

Vestibular dysfunction is a problem with the body’s balance system. This disorder can be caused by issues in different parts of the body, categorized as ‘peripheral’ and ‘central’ based on which area is impacted. The signs of both types of vestibular dysfunction can be quite similar, making an in-depth physical check-up necessary to tell them apart. Vestibular disorders usually appear suddenly, with the most frequent type of acute, or sudden-onset, peripheral vestibular dysfunction being benign paroxysmal positional vertigo (BPPV), a non-dangerous type that comes and goes with changes in head position.

Stroke, a blockage of blood flow to the brain, is the most common cause of severe central vestibular dysfunction. Specifically, these are strokes that happen in the back part of the brain which houses the brainstem and cerebellum. Strokes account for one-quarter of patients who exhibit signs of central vestibular dysfunction. Notably, strokes are treated differently from other causes of imbalance, so it’s critical to identify them quickly. A disease affecting the vertebrobasilar artery can lead to a stroke in 5% of patients, and patients with this condition often have fainting episodes and/or balance problems. The second most common cause of central vestibular dysfunction is a demyelinating disease, which is a type of disorder that damages the protective covering of nerve fibers.

Symptoms of vestibular dysfunction can vary widely and include dizziness, nausea and vomiting, a difficulty in moving the head, unusual eye movements, difficulty in walking, and imbalances while standing. Each symptom can present differently in each person, and no single symptom uniquely identifies vestibular dysfunction. If a group of these symptoms is present, it should prompt a suspicion for vestibular dysfunction. A complete review of the patient’s history along with a physical check-up is the recommended way to differentiate between peripheral and central vestibular dysfunction.

It’s crucial to identify the type of vestibular dysfunction a patient has, as it informs the treatment approach and the urgency to start treatment. Peripheral vestibular disorders are generally treated by addressing the symptoms, whereas central vestibular dysfunction caused by a stroke may require an emergency medicine to dissolve blood clots or a procedure to remove it. Early detection of demyelinating disorders, like multiple sclerosis is important, allowing for immediate treatment to avoid quick deterioration and disability.

This explanation covers the occurrence, history, and physical check-up, evaluation, potential diagnoses, treatment, complications, and key points in diagnosing and managing vestibular dysfunction and distinguishing between peripheral and central vestibular disorders.

What Causes Vestibular Dysfunction?

Vestibular dysfunction, or problems with your body’s balance system, can be caused by issues in two main areas – peripheral or central. Peripheral problems are located in the balance system itself, which includes the inner ear and related nerves. Central problems come from disorders affecting the central nervous system, that part of your body which includes your brain and spinal cord. These problems can happen suddenly or over a long period.

Acute vestibular syndrome, for one, happens suddenly and could last for a day or more. It comes with a range of symptoms including dizziness, nausea, vomiting, feeling unsteady when moving your head, problems with walking, and difficulty maintaining balance. There’s an exception though, called paroxysmal positional vertigo.

This vertigo is a mechanical problem in your inner ear that could give you brief periods of sudden dizziness and other physical symptoms. Benign paroxysmal positional vertigo (BPPV) accounts for 1 in 5 people who experience moderate to severe dizziness or vertigo. It mostly affects women and anyone over the age of 50.

BPPV typically causes bouts of dizziness that may happen several times a day but only last for less than one minute. It’s caused by calcium carbonate-protein crystals that have detached from inner parts of the ear and moved to another part. This creates a spinning sensation when you move your head. Another common disorder is Ménière disease, which brings dizzy spells lasting several minutes or hours, along with hearing loss and a roaring sound inside the ear.

There are several proposed explanations for this disease. One suggests a blockage at the entrance of a fluid-filled sac in the inner ear, caused by detached crystals. Another theory points to a problem with the tiny canal regulating the amount of fluid in the inner ear. A third possibility could be a not-fully-understood immune response that may explain its association with allergies. Some patients may have a genetic factor as well. People with Ménière disease who have a family history often experience more severe symptoms with each generation. However, a specific gene has not been identified yet. There may also be a link between migraines and Ménière disease, possibly related to irregular blood flow.

Another theory suggests that the rupture of the fluid-filled sac in the inner ear disrupts the balance in the neighbouring fluid space. This causes the sensory cells inside the ear to lose function. The process repeats, leading to gradual deterioration of these cells. Direct injury can also cause vestibular damage such as in the case of a head trauma or a whiplash injury.

In conditions closely similar to Ménière disease but with the absence of hearing loss and inner ear noises, diagnosing could be difficult. While bilateral disease may develop in up to 17% of patients, it is much more likely to occur one after another (78%) than at the same time (22%).

Other common causes of vertigo include vestibular neuronitis, believed to be caused by a viral inflammation of a nerve in the inner ear, and labyrinthitis — when the inflammation also affects the inner ear and causes hearing loss. Several other conditions might result in an unbalanced balance system, including autoimmune disorders, tumors in the inner ear, temporal bone fracture, certain medication side effects, and abnormalities of the inner ear.

Central causes for an unbalanced balance system are mostly due to problems with blood supply to the back part of the brain, strokes affecting the brain stem, cerebellum, and brain, and diseases that cause damage to the protective coating of the nerves like multiple sclerosis. Brain injuries like a concussion might also cause a central vestibular dysfunction. Taking a patient’s medical history and physical examination plays a crucial part in identifying the causes of vestibular dysfunction because of its wide array of possible causes.

Risk Factors and Frequency for Vestibular Dysfunction

Vestibular dysfunction, which often causes dizziness, is a common problem particularly for people aged 40 and over. It can lead to around 10 million healthcare visits and accounts for a quarter of all visits to the emergency room every year. This condition is strongly linked to stroke and diseases that damage the protective covering of nerve fibers. In fact, 25% of patients with vestibular disorders have also had a stroke. Patients with this condition are more likely to fall because of issues such as vertigo and trouble with balance. Falls are a major cause of injury and death, especially in patients aged 70 and over.

This condition is not rare, with 4.9% of people experiencing vestibular dysfunction within a year and 7.4% experiencing it at some point in their lifetime. Certain factors make a person more likely to suffer from this. These include being female, having a lower level of education, being over the age of 40, suffering from heart disease, and having depression.

• Vestibular dysfunction often causes dizziness and is common in people aged 40 and over.
• It leads to around 10 million healthcare visits annually and accounts for 25% of emergency room visits.
• There is a strong link between this condition and both stroke and demyelinating diseases.
• 25% of patients with vestibular disorders have had a stroke.
• Patients with this condition are more prone to falls due to vertigo and imbalance.
• Falls due to this condition can lead to severe injury or death, especially in those aged 70 and over.
• 4.9% of people experience this condition within a year, and 7.4% experience it at some point in their lifetime.
• Risk factors include being female, having a low level of education, being over 40, cardiovascular disease, and depression.

Signs and Symptoms of Vestibular Dysfunction

Identifying the cause of balance and dizziness issues involves initial steps like history-taking and conducting a physical exam. The doctors try to isolate when these episodes happen and how they present. For some patients, they might describe their dizziness in vague terms and their notions of imbalance can be confused for fainting-related symptoms.

The progression of symptoms over time also offers key insights. Many times, vertigo isn’t a constant issue, because the brain learns to compensate and reduces feelings of dizziness over time. But if someone reports constant vertigo for months on end, a peripheral cause is unlikely. Yet, when tinnitus (ringing in the ears) occurs, it could suggest a peripheral issue that affects both hearing and balance such as Ménière disease. Most importantly, the length of the episodes can determine whether the cause is peripheral (affecting the extremities of the body) or central (affecting the central nervous system).

Typical triggers are also significant. If vertigo gets worse with head motion, vestibular causes (issues with the inner ear and brain that control balance and eye movements) may be implicated. If coughing, sneezing, exertion, or loud sounds exacerbate symptoms, then a condition like perilymphatic fistula, a defect between the middle ear and inner ear, might be likely. Patients at high risk of perilymphatic fistula include those with a history of physical trauma, surgery on the inner ear region, or intense activities such as weight lifting.

Symptoms that accompany vertigo can hint at the root cause, too. If vertigo comes with double vision, speech issues, numbness or weakness, then brain-related conditions like stroke or multiple sclerosis could be responsible. Meanwhile, a history of migraines could link vertigo to this condition, and a detailed medical history can provide more clues about the underlying cause.

During a physical exam, patients may exhibit nystagmus (involuntary eye movement). This symptom can help the doctor differentiate between peripheral or central disorders. There are multiple types of nystagmus, and any clinically significant nystagmus should be closely examined, as it can provide critical diagnostic information.

Several specific tests can help in the diagnosis, such as:

• Rinne and Weber tests: These assess conductive and sensorineural hearing using a tuning fork.
• Dix-Hallpike-maneuver: A positional change is used to reproduce vertigo and determine issues with dizziness.
• Head impulse test: This tests differentiates between vestibular dysfunction from non-vestibular dizziness.
• Head shaking nystagmus testing: This is used to test for unilateral vestibular lesions.
• Skew deviation: This test is designed to identify lesions in the brainstem.
• HINTS examination: This combines the head impulse test with the skew deviation test to distinguish between central and peripheral vertigo.

Testing for Vestibular Dysfunction

If you’re having issues with balance or dizziness, your doctor might need to test your vestibular system, which is the part of your inner ear and brain that controls balance and eye movements. There are several tests they might use, including magnetic resonance imaging (MRI), computed tomography (CT), electronystagmography (ENG), videonystagmography (VNG), vestibular-evoked myogenic potentials (VEMP), and auditory brainstem responses (ABR). Not all these tests are always performed because some might not give additional useful information and only add to the cost.

Two common tests for balance problems are the electronystagmography and videonystagmography, which are ways to measure involuntary eye movements called nystagmus. ENG uses special electrodes that measure these eye movements, while VNG uses cameras. These tests often involve activities like following lights with your eyes, undergoing positional testing like the Dix-Hallpike maneuver (a test where you’ll rapidly move from a sitting to a lying position), and undergoing caloric testing (where warm and cold water or air is gently introduced to your ear to see how your balance system responds).

VEMP testing is another test your doctor might use. There are two kinds of VEMP tests, cervical and ocular. Both types work in a similar way—they involve giving your ears a loud sound and watching your muscle reactions. Lower thresholds or stronger reactions for these responses might be a sign of certain disorders.

Brain imaging might be needed if other tests, your medical history, and/or your physical examination suggest a problem with the brain. Patients with risk factors for stroke or symptoms of neurologic problems are often recommended to have neuroimaging. This can help doctors check for things like a stroke by producing detailed images of the brain. Younger patients who have symptoms of vertigo without other risk factors or certain symptoms might not need immediate imaging, unless their symptoms last for more than 48 hours.

Brain MRIs provide very detailed images and are good at detecting conditions like strokes. CT scans are not as sensitive for certain brain conditions but can quickly and effectively find things like bleeding in the brain. For these reasons, a CT scan is often the first test done when a stroke is suspected.

Treatment Options for Vestibular Dysfunction

The treatment for vestibular dysfunction, a condition affecting balance and spatial orientation, largely depends on its cause. Most patients primarily receive treatment to manage their symptoms. This treatment might include antiemetic medicines that help control nausea and vomiting, vestibular suppressant drugs that reduce dizziness and loss of balance, or benzodiazepines that help to calm the brain and nerves.

If the cause of vestibular dysfunction is suspected to be autoimmune labyrinthitis or Cogan syndrome, which involve inflammation in the ear, high-dose oral steroids might be prescribed. Other types of labyrinthitis and vestibular neuritis, which create inflammation in the inner ear and the nerves connecting the inner ear to the brain, are often temporary and could be monitored without specific treatment. However, surgical options might be needed in cases of persistent Ménière disease (a disorder of the inner ear that leads to severe dizziness) or when a mass lesion like an acoustic neuroma (a benign tumor) is present.

For a common condition like benign positional vertigo, special maneuvers like the Epley, Semont, Foster maneuvers, and Brandt-Daroff exercises are used. These are certain positions and movements guided by a specialist that help to clear the affected ear canals. The Semont and Foster maneuvers and Brandt-Daroff exercises could be performed by the patient independently if instructed correctly.

The treatment goal for Ménière disease involves reducing the occurrence and severity of vertigo attacks, hearing loss and ringing in the ear (tinnitus), easing chronic symptoms, and minimizing disability. Lifestyle changes and avoiding triggers are key. This could include a low-sodium diet, limiting caffeine, alcohol, nicotine, stress, use of monosodium glutamate in food, and exposure to allergens. If these measures fail, treatments like injecting medicine known as steroids into the ear, or using overpressure devices that provide air pressure pulses to the affected ear to help with fluid drainage, could be useful.

If these approaches do not work, surgical treatments are available. One surgical technique involves creating a pathway for the excessive fluid in the inner ear to drain into the cavity behind the ear. Some extreme treatment options for Ménière disease include the injection of a drug known as gentamicin into the ear, nerve surgery, or removal of the inner ear. These methods aim to reduce the function of the vestibular system (the system that contributes to balance) in the affected ear to help alleviate symptoms.

What else can Vestibular Dysfunction be?

If a patient experiences dizziness and vertigo, doctors need to decide if the cause is related to the nervous system (central) or related to the inner ear (peripheral). This helps narrow down the possible causes, which are also known as the differential diagnosis.

The diagnosis will lean towards a central cause when the unsteady feeling and spinning sensation continue even when the patient’s position or sight is changed. This may be the case if there are other neurological symptoms or risk factors for a stroke. Common conditions from central nervous system problems that can cause these symptoms include:

• Blockage or damage to parts of the brain (Infarctions) in areas like the brainstem, cerebellum or medulla
• Tumors in the cerebellum
• Chiari malformations, where the lower part of the brain extends into the spinal canal
• Multiple sclerosis
• Vestibular migraines
• Mal de debarquement syndrome, usually felt after sea travel
• Progressive nervous system disorders like Parkinson’s disease

On the other hand, peripheral vestibular dysfunction occurs when the dizziness changes with movement. This is often when the patient’s eyes make uncontrolled repetitive movements horizontally. Conditions to consider in this case include:

• Benign paroxysmal positional vertigo (BPPV)
• Ménière’s disease
• Vestibular neuritis, inflammation of the inner ear
• Labyrinthitis, inflammation of the inner ear
• Less common causes such as tumors near the inner ear, tear in the inner ear, Cogan syndrome affecting the eyes and ears, drugs affecting the ears and middle ear infections

Additional symptoms and timing will help the doctor arrive at the right diagnosis. For example, hearing loss may point to Mediere’s disease, Cogan syndrome or drug toxicity.

Patients might also describe feeling light-headed or unsteady, often referred to as “dizziness”, even if they don’t actually have vertigo. Possible causes of this kind of dizziness include low blood pressure, dehydration, anxiety, diabetes or heart disease. Overall, there are plenty of factors to consider when diagnosing dizziness, and determining the exact cause can take some time.

What to expect with Vestibular Dysfunction

The outcome for patients with a malfunctioning vestibular system, which is responsible for maintaining balance, greatly depends on what causes the problem. The treatment outcome for Benign paroxysmal positional vertigo (BPPV) – which is an issue where you feel like you’re spinning – is usually positive if treated properly, but it can often come back.

Ménière’s disease, on the other hand, is a condition that causes repeated episodes and gets worse over time. This leads to both hearing loss and balance problems and can eventually make routine activities difficult. In almost half of the cases, the issue can affect the second ear as well, though this usually happens in sequence and not at the same time. While lifestyle adjustments and managing symptoms can slow down the progress of the disease, they might not be able to stop it altogether.

Some conditions of the vestibular system like vestibular neuritis and labyrinthitis, which are inflammation of the inner ear, can resolve on their own even though they initially may cause severe symptoms.
The outlook for vertigo caused by central lesions – abnormal tissues resulting from injury or disease – is fair as patients often improve with physical therapy over time. However, other side effects from strokes or tumors can greatly affect the patient’s life.

Possible Complications When Diagnosed with Vestibular Dysfunction

Vestibular disorders, which affect balance and spatial sense, can lead to significant complications such as an increased risk of falling and reduced quality of life. This can particularly impact elderly individuals as, serious falls in this age group can lead to severe injuries or even death. Furthermore, severe vertigo, a typical symptom of vestibular disorders, imposes limitations on daily activities most people take for granted, including driving cars, using machinery, bike riding, running, and even basic mobility, such as walking. These restrictions can often result in an inability to continue working, particularly in the same professional field. In cases where the vestibular disorder arises from peripheral issues, there may be additional issues like hearing loss, which could further increase the disability. Similarly, other nerve or neurological symptoms may accompany conditions with Central Nervous System (CNS) origins.

Common Complications of Vestibular Disorders:

• Inceased risk of falling
• Decreased quality of life
• Severe injuries or even death in the case of elderly individuals
• Significant restrictions on daily activities like driving, using machinery or physical activities
• Loss of employment or job shifts
• Hearing loss if the vestibular disorder is due to a peripheral issue
• Additional neurological or nerve-related symptoms if the condition is attributed to CNS origins

Preventing Vestibular Dysfunction

Vestibular dysfunction, or problems with the part of your inner ear that helps control balance, can cause a wide range of symptoms that vary in severity and frequency. These symptoms can sometimes significantly affect a person’s life and cause anxiety. Educating the patient about their condition is a key part of managing it effectively.

The first step in treatment is getting an accurate diagnosis. This is achieved by collecting a detailed personal health history, conducting a thorough physical examination, and using additional tests for support. Once they have a clear picture of the situation, the doctor will explain the diagnosis and what can be expected moving forward.

The following step is to create a personalised care plan to aid the patient in managing their condition. This approach encourages patients to become actively involved in their own care. While medication can often help control symptoms, it’s important for patients to understand that these medications may have side effects and could interact negatively with other drugs they might be taking.