What is Vestibular Neuronitis?
Vestibular neuritis, sometimes called vestibular neuronitis, is believed to be caused when the part of the nerve in your inner ear that helps control balance becomes inflamed. This is typically linked to a recent or ongoing viral infection. The common symptoms include feelings of dizziness, nausea, and difficulty with balance. The good news is that this is usually a harmless condition that gets better on its own over a few days, although it could take several weeks or even months before all balance-related symptoms completely disappear.
This condition is diagnosed based on symptoms and a doctor’s examination, and part of the challenge is to ensure that it is indeed vestibular neuritis and not something more serious like cerebrovascular syndromes (conditions that affect the blood vessels supplying the brain), which can have similar symptoms.
The main treatment for vestibular neuritis is simply to help manage the symptoms. This often involves medications like those used to combat nausea (antiemetics), antihistamines to reduce inflammation, and benzodiazepines for the relief of severe anxiety and to help with sleep. Once the initial bouts of nausea and vomiting are under control, it could be helpful to start vestibular rehabilitation which is a kind of therapy aimed at helping your body and brain regain their ability to process balance information correctly.
What Causes Vestibular Neuronitis?
Vestibular neuritis is thought to be a condition that causes inflammation particularly in the vestibular part of the eighth cranial nerve, which is responsible for balance and eye movements. Scientists believe a virus is likely the cause of this condition.
Risk Factors and Frequency for Vestibular Neuronitis
There isn’t a lot of information available about the rate of acute vestibular neuritis, a cause of dizziness and vertigo. It does, however, fall as the third most often diagnosed cause of peripheral vertigo, coming after BPPV and Meniere disease. It’s estimated that about 6% of patients coming to US emergency departments with complaints of dizziness are diagnosed with acute vestibular neuritis or labyrinthitis. However, these numbers might be less than the real rate of this condition because a further 22% of patients leave the hospital with a nonspecific diagnosis of “dizziness” or “vertigo”. Undoubtedly, some of these vague diagnoses include undiagnosed cases of acute vestibular neuritis. This condition doesn’t favor any gender and usually affects people in their middle ages.
Signs and Symptoms of Vestibular Neuronitis
Vestibular neuritis is a condition that primarily involves symptoms like dizziness, feeling sick, vomiting, and problems with balance. Different from other problems that can cause similar symptoms, like BPPV or Meniere’s disease, in vestibular neuritis these symptoms seem to stay the same instead of coming and going. Most of the time, patients notice that these symptoms gradually worsen over the first 24 to 48 hours before sticking around for a few days and then starting to get better. Around half of the patients have also had a viral infection, such as a cold, recently.
When it comes to vestibular neuritis, the physical examination generally doesn’t show anything out of the ordinary. However, the doctor may check for a few specific things to make sure that the vertigo isn’t being caused by a different problem. This is particularly important if the patient has other symptoms, such as changes in vision, changes in sensation, speech problems, clumsiness, or challenges with walking. If the patient has one-sided hearing loss, then the diagnosis might change from vestibular neuritis to labyrinthitis.
Generally, besides vestibular neuritis, there are other peripheral causes of vertigo, such as BPPV and Meniere’s disease, which can be identified by their episodic nature of symptoms. However, the HINTs examination, a special test for vertigo, helps differentiate vestibular neuritis from other causes. The test includes three steps:
- Head Impulse: Checking if the patient’s eyes can maintain focus on the examiner’s face while their head is quickly turned,.
- Nystagmus: Noting if a patient’s eyes move in a specific pattern when they’re looking straight ahead,.
- Test of Skew: Observing if the patient’s eyes maintain alignment when one eye is briefly covered.
In vestibular neuritis patients, this test usually points to a peripheral cause for the vertigo. It’s important for the doctor to also check for problems with talking, swallowing, facial weakness, coordination, weakness, changes in sensation, and changes in reflexes, even though these are typically not present in individuals with vestibular neuritis. Hearing is generally not affected in vestibular neuritis, but if the patient does have hearing loss, the diagnosis may change to labyrinthitis. The doctor may also observe the patient’s walking style and posture, as this might help identify which ear is affected, or signal a more serious condition. Typically, a patient with vestibular neuritis has normal posture when sitting, but when they walk, they might lean or fall towards the affected side.
Testing for Vestibular Neuronitis
If you’re experiencing acute vestibular dysfunction – sudden dizziness or the feeling as if the surroundings are spinning – your doctor will rely on your signs and symptoms to diagnose the condition. However, since vestibular neuritis (an inflammation of your inner ear that can result in vertigo) is a diagnosis of exclusion, meaning it can only be determined after the doctors rule out all other possible reasons for your symptoms, the primary goal for your doctor will be to make sure that your symptoms aren’t caused by a stroke.
In most cases, doctors don’t need to use neuroimaging (like MRI or CT scans) of the brain to diagnose this. However, if your physical exam results are not lining up with the expected signs of an inner ear problem, if you have risk factors for stroke, or if your symptoms don’t get better within 48 hours, your doctor may order these scans. MRI is more sensitive than a CT scan in ruling out a stroke.
Some other tests, such as cervical and ocular vestibular evoked myogenic potentials, which measure the sound sensitivity of muscles in the ears and eyes, and video head impulse testing, which evaluates how well your eyes can track moving objects when your head is also moving, can provide further information about which part of your vestibular system may be affected in vestibular neuritis.
Treatment Options for Vestibular Neuronitis
Vestibular neuritis, a condition affecting your balance, is usually treated with medication initially to help manage symptoms. These medications can include drugs that prevent vomiting and nausea (antiemetics), drugs that reduce dizziness and motion sickness (antihistamines), and drugs that calm the nerves (benzodiazepines). After this initial phase, therapies like vestibular rehabilitation, which aims to improve balance and eye movements, may be recommended.
An important note is that the above-mentioned medications should only be used for a short period, ideally no more than three days. This is because long-term use might slow down the body’s natural ability to recover and potentially lead to chronic (long term) issues and recurring dizziness.
In the past, corticosteroids have been considered as a treatment option. Corticosteroids are drugs that reduce inflammation in the body. However, their effectiveness for vestibular neuritis is debated. One 2011 review of medical studies on the topic found that there was not enough evidence to recommend corticosteroids for this condition.
As some believe that vestibular neuritis might be caused by a virus, there has been a theory that antiviral medications could help. An example of such a medication is valacyclovir. However, its effectiveness in treating vestibular neuritis, whether used on its own or combined with a drug that reduces inflammation (glucocorticoid), has not been proven.
What else can Vestibular Neuronitis be?
When a patient comes in with vertigo, doctors try to determine the cause. This could be something going on in the peripheral (outer) areas or central (inner) parts of the body. The patient may or may not also be experiencing hearing loss. Here are some potential causes:
Causes related to the peripheral areas include:
- Benign paroxysmal positional vertigo (BPPV) – This can cause brief episodes of mild to intense dizziness that are triggered by specific changes in the position of your head.
- Meniere disease – This disorder of the inner ear characterized by episodes of feeling like the world is spinning (vertigo), ringing in the ears (tinnitus), hearing loss, and a fullness in the ear.
- Labyrinthitis – This is an inflammation of the inner ear that often causes vertigo and hearing loss.
Causes related to the central areas include:
- Vestibular migraine – a type of migraine that may cause vertigo, difficulties with balance, and dizziness.
- Vertebrobasilar TIA or brainstem ischemia/infarct – These conditions are associated with the disruption of blood flow to the brain, which can result in vertigo. They are typically seen in individuals with vascular risk factors or a history of trauma.
- Cerebellar infarct or hemorrhage – Causes of these conditions can include stroke or bleeding in the brain.
Causes when hearing loss is present:
- Perilymphatic fistula
- Cholesteatoma
- Meniere disease
- Labyrinthitis
- Acoustic neuroma
- Autoimmune processes
- Psychogenic causes
Causes when hearing loss is absent:
- Benign positional paroxysmal vertigo
- Vertebral basilar insufficiency
- Migraines
- Vestibulopathy
- Vestibular neuronitis
- Central nervous system disorders
- Lyme disease
- Multiple sclerosis
What to expect with Vestibular Neuronitis
This condition usually resolves without complications in most cases. However, some people might continue to experience symptoms even after a year, as indicated by a study which noted that 15% of participants still had symptoms at this point.
The chance of getting vestibular neuritis again is quite low, as only 2 to 11% of patients have been reported to experience a recurrence of the condition in various studies.
Possible Complications When Diagnosed with Vestibular Neuronitis
: Vestibular neuritis, an inflammation of the inner ear that causes problems with balance, often leads to two main complications – benign paroxysmal positional vertigo (BPPV) and persistent postural-perceptual dizziness (PPPD). BPPV, which causes brief episodes of mild to intense dizziness, may develop in 10 to 15% of patients who have vestibular neuritis, usually showing up in the affected ear within a few weeks. On the other hand, PPPD is a more recent term that describes a condition with symptoms of non-spinning vertigo (a sense of feeling off-balance) and unsteadiness. This condition combines features of long-term dizziness felt subjectively, phobic postural vertigo (a fear of falling or being off-balance), and other related disorders. In a study, 25% of patients had PPPD 3 to 12 months after having acute or episodic vestibular disorders.
Complications of Vestibular Neuritis:
- Benign paroxysmal positional vertigo (BPPV)
- Persistent postural-perceptual dizziness (PPPD)
- Long-term subjective dizziness
- Phobic postural vertigo
Preventing Vestibular Neuronitis
If you suddenly begin to feel severe, recurring dizziness that lasts from several hours to a few days, you may have a condition known as vestibular neuritis. This is something that you should definitely talk to your doctor about.
You could reach out to your general doctor, consult an emergency doctor, or see an ENT physician, who specializes in issues related to the ears, nose, and throat.
Your doctor will first want to rule out that your dizziness isn’t being caused by another, more serious condition effecting your brain or blood vessels. If they suspect that you do have vertigo, which is this sense of spinning or dizziness, they may refer you to an ENT specialist. This specialist can then run further tests and explore treatment options for you.
