Vestibular System Recap
Your vestibular system assists heavily with your balance. It is comprised of the vestibular organ in the inner ear (the sensor/GPS unit), your brain (the processor) and the vestibular nerve which what links the inner ear to the brain.
The vestibular organ can be thought of as mini-GPS units. You have one in each ear which picks up on body position/movement and sends that information to your brain via the vestibular nerve. Your brain then processes this information and sends out messages to your eye, neck, trunk, arm and leg muscles to help you maintain balance.
What is vestibular neuritis
Vestibular neuritis is the 3rd most common cause of vertigo. It is caused by a virus that causes inflammation of the vestibular nerve. If often attacks only one ear/side. Patients often report having a head cold prior to the event. This causes severe constant vertigo, dizziness, nausea and imbalance that can last a few hours and up to 2 days.
Vestibular neuritis involves 2 stages (acute and sub-acute/chronic). The initial acute phase normally lasts around 1-3 days, where the vestibular nerve is accurately inflamed. This inflammation disrupts the vestibular nerve whose main job is
to send messages from your inner ear to your brain about head and body position which causes the messages to be inaccurate. This will confuse your brain into thinking your head is constantly moving, which can result in vertigo and nausea.
This can cause:
- Sudden onset of vertigo (room spinning)
- Nausea/vomiting
- Severe head and environment motion sensitivity
- Significant imbalance and/or falls
- Blurry vision, difficulties focusing and tracking objects
- Often patients go to hospital/ED
After the acute stage passes, symptoms are reported to be less severe as the inflammation subsides.
Patients often report:
- Brain fog and light headedness
- Feelings of disorientation and “haziness”
- On and off dizziness especially with quick head movement or environment motion
- Dizziness when eyes are closed (i.e closing eyes in the shower)
- Mild nausea
- Imbalance and difficulty walking in busy environments (i.e shopping centres)
- Difficulty concentrating
Why do I still feel symptoms after the acute phase? What is vestibular hypofunction?
Although the initial inflammation has subsided the resultant damage to the vestibular nerve (vestibular injury) disrupts the ability of sensory messages to reach the brain from the affected ear. Often the damage can cause less, slower and/or inaccurate messages from the inner ear to the brain. This decreased sensory input from the affected ear is often termed “vestibular hypofunction”.
Unfortunately, our body has a limited ability to repair the inner ear system. However, our body can compensate for the vestibular injury by recalibrating the parts of the brain that control balance. This happens when the brain recognises that the messages/function of one inner ear is down and or inaccurate. It will then rely less on the information from that ear and more on the other unaffected ear. This compensation occurs naturally in some people and will normally and will result in complete resolution of symptoms. However, at times, it can be unsuccessful which results in the chronic symptoms and vestibular rehabilitation may be required.
Why do I feel fine sitting still, but only get dizziness when I move or turn my head, in busy environments or when I close my eyes…
When you are sitting still, there is less reliance on the vestibular system to help with balance. The vestibular system really comes into play when you are moving, particularly when you are turning your head. If the function of one side is lower, this provides inaccurate information, and the brain struggles to process and act on this information which can result in vertigo and imbalance. People often find they feel vertigo or lose balance when they turn their head towards the affected side.
Vision is extremely important in balance as it tells us what upright/vertical is. When vision is removed (i.e eyes closed in shower or at night), the brain is forced to rely more on the input from the vestibular system for balance. If the information is inaccurate, it can cause vertigo and imbalance. Patients fall towards their affected side, as that side is receiving less sensory input.
A similar thing happens when you are in a busy environment. Instead of using your eyes to help balance, they are more focused on visual distractions (i.e supermarket aisles or making sure you don’t walk into someone), meaning your brain is again forced to rely more on the vestibular system for balance.
Why me, why did I not compensate?
It is not well understood why some people are able to compensate automatically whilst others struggle. Evidence shows the older population and patients with a history of migraines, anxiety, and/or depression struggle to compensate. Additionally, medications that make the brain sleep including anti-dizziness medications, if used long term can slow down or stop the compensation process from happening. Often patients that start avoiding certain movements, and/or rely on anti-dizziness medications daily are the most likely to not compensate, which is where vestibular rehabilitation is important.
Why see a vestibular physiotherapist?
If you relate to any of the above symptoms, it is advised to be assessed and treated by a trained vestibular physiotherapist. Often patients who do not successfully compensate after vestibular neuritis, just put up with their symptoms and adapt their lifestyle. They begin to learn ways to avoid aggravating activities. This often includes:
- Slow walking speed
- Avoid turning their head, instead whole trunk
- Avoiding leisure/sports (golf, pilates, yoga, walking)
- Avoid leaving the house
- Avoid going to shopping centres
This may be helpful in the short term but very detrimental in the long run. Balance is a skill and the ability of the brain to process sensory information is a skill. If you do not USE IT you will LOSE IT. If you continue to avoid activities weeks after a vestibular neuritis, you are no longer challenging your balance and brain processing skill and overtime these skills will decrease quickly and your symptoms will worsen over time.
Our vestibular physiotherapist will perform a thorough initial assessment which includes oculomotor, balance and vestibular system specific tests to determine if it is a vestibular neuritis/hypofunction or other vestibular condition, determine which side is affected and prescribed an individualised vestibular rehabilitation program based on the assessment findings. It is important these exercises are performed frequently as this will drive your brain to compensate. Patients normally feel significant improvement within the first 2 months of commencing vestibular rehabilitation.
If you have had any of these symptoms mentioned above or you tick quite a few boxes whilst reading this, we recommend you book in with a vestibular physiotherapist to return you to moving well!
John Ma
Vestibular Physiotherapist