In this second part of the vestibular series, we will discuss the physiotherapy approach to assessing vestibular disorders and dysfunction.
Because describing symptoms of vestibular dysfunction is so personal, subjective and at times emotional, a person-centred assessment must be undertaken to fully understand the extent and severity of the problem. In short, the best way to start treating the inner ear is to lend them one.
Rule #1 Be Sensitive
Pick up on everything that could rule in or out a condition. Now is the time to be really thorough, open minded and sensitive to anything that could be happening. Examples of questions to ask yourself or of someone include:
- how long has this been happening for?
- what were the circumstances in which this occurred? was stress involved?
- how well do you sleep?
- have you changed your diet recently?
- any hormone replacement or supplements?
- what other medical conditions are present?
- have you had a history of cancer?
- what medications are you on? could it be potentially damaging to your vestibular system
- how did it start?
- how did it progress?
- what triggers it?
- is it constant?
- how long do symptoms last for?
- what positions is it most challenging?
- how frequent do they occur?
- are you sensitive to light?
- do you hear sounds?
- can you hear high and low pitch sounds as easily?
- can you describe all your symptoms in your own words without using the word ‘dizzy’?
The last question is perhaps the most important question because determining what the full set and description of symptoms are really helps work out what is happening, and importantly WHERE it might be coming from. For example, a condition that does not seem to alter with positional changes in space is unlikely to involve the semicircular canals. Another example is high pitched ringing in the ears (tinnitus). If it pulsates then perhaps there is a vascular or hypertensive component, whereas if it doesn’t then we may consider assessing conductive or sensorineural hearing loss as well, and consider conditions such as Meniere’s disease.
As a vestibular patient once myself, it can be difficult to not be biased when one handed a diagnosis from someone else who hasn’t really understood the problem or examined all the evidence, and because of this we need to be allowed time to explain everything that is happening truthfully.
The best way to look at a problem of this nature is have it assessed by a trained health professional who is skilled in vestibular assessments to determine whether the problem is in the brain or in the vestibular apparatus, or elsewhere like the neck or other metabolic, psychological and medication-related conditions that share its pool of symptoms.
For example, having a small stroke or blood clot in the brainstem can mimic some of the symptoms in benign paroxysmal positional vertigo (BPPV) but the management of the two are vastly different. That is why we need to be pick up as many consistent clinical features as possible in formulating an accurate diagnosis.
The last point here I will mention is this, which tends to occur in chronic settings:
Is what I am seeing relating to the cause? Or is it compensation?
Rule #2 Be Specific and Precise
Next we need to actually test the vestibular, balance and brain systems, and be highly precise in doing so to reduce false positives or negatives.
This is done with:
- observation of the static eye
- observation of the facial muscles
- observation of the eye when tracking a slow moving object
- observation of the eye when tracking a fast moving object
- vestibular ocular reflex (VOR) testing
- head thrust test
- vestibular dynamic visual acuity test
- movement and positional testing
- balance and walking assessments
- examination of the neck, sensory systems, range of motion and coordination as needed
Some tests are more specific than others, but they all help form the clinical picture of the individual’s problem from an anatomical to a functional level. For the majority of cases, these assessments will be enough to formulate a working diagnosis.
It is also at this point where we must decide whether we need more information from further investigations, tests or another health professional’s input to confirm or deny anything ambiguous or suspiciously sinister.
Why an understanding of neurology is important here
There is a common misconception that vestibular disorders only relate to the vestibular apparatus. As you can classify vestibular disorders as peripheral (relating to the vestibular apparatus, the neck or some other body part) or central (relating to the brain). As a health professional trained in understanding neuroanatomy, we can begin to infer from clinical signs where the lesion might be.
For example, true centrally driven vertigo is the result of an imbalance of neural activity that can happen anywhere from the posterior cerebellum to the brainstem through to the labyrinth. If there are any of the classic 5 signs of sudden loss of posture, double vision, difficulty speaking, dizziness and clumsiness, then we would be highly suspicious of a posterior cerebellum lesion. Lesions above the posterior fossa usually result in lightheadedness and imbalance without any vertigo. Vertigo driven by peripheral conditions such as labrynthitis are usually one sided and can be picked up with a head thrust test.
Once we have established that the problem has been 1) diagnosed, 2) stable and 3) manageable at home, we can look at beginning forms of vestibular rehabilitation. We will explore this in detail in Part 3 next week and the sort of activities we would do to get this happening effectively.