ENT specialists usually classify vertigos based on their duration:
- vertigo lasting seconds: benign paroxysmal positional vertigo.
- vertigo lasting minutes: benign paroxysmal vertigo or childhood vertigo.
- vertigo lasting hours: recurring vertigo like hydrops.
- vertigo lasting days: brutal destruction of a peripheral organ.
Benign paroxysmal positional vertigo (BPPV) is a mechanical disorder. This is not a lesion of the inner ear. This means that we do not observe any spontaneous signs. If a spontaneous nystagmus is observed, it means that it is not a BPPV, or alternatively that it has developed in parallel to another inner ear disorder. The physiopathology is as follows: it is an eggshell coloured amalgam moving about in the posterior semi-circular canal. When the amalgam is lightly knocked using a soft instrument, it falls apart and turns into a sludge-like substance. The amalgam is made of calcium carbonate crystals linked together with proteins. These bonds give the amalgam the texture of a glue. Movement of the amalgam under the effect of gravity in the posterior CSC is going to provoke an ipso-facto movement of the cupula. Movement is towards the canal due to the effect of suction if the amalgam moves away from the ampulla, and towards the utricle if the amalgam moves towards the cupula. Movement of the cupula teaches us that the vertical canal sends a signal when the cupula moves towards the canal. This is when the subject moves the head in such a way that the posterior CSC is vertical to the ampulla, towards the top so that the movement towards the canal arc will provoke a signal. This signal manifests itself as a torsional nystagmus beating towards the damaged ear. The triggering position when the subject is lying down with their head turned at a 45° angle to one side facing upwards. The only treatment for this disorder is Sémont’s liberatory manoeuvre. This therapeutic manipulation is not reeducation per se and a separate chapter has been dedicated to it.
Benign paroxysmal vertigo is called childhood vertigo and can be found in certain young subjects and according to numerous authors, is tantamount to a migraine. The vertigo is short-lived, and with few exceptions, and only in exceptional cases are there any spontaneous signs. In other words it is incredibly rare for children to be required to undergo vestibular rehabilitation. Furthermore, treatment with medication is the most common solution.
Recurring vertigo is a vertigo lasting from several minutes to several hours. It is in fact a rotatory vertigo with nausea and vomiting. The subject is severely debilitated, and depending on the acuteness of the vertigo and its duration, they may even need to lie down in the dark, with all the difficulties that that this entails by vomiting without aggravating the vertigo and so on. The vertigo can be both isolated or can be accompanied by a hearing loss prior to the attack of vertigo. There could be tinnitus and a feeling of fullness in the ear. All are possible. One should remember it is labelled vertigo or Ménière’s disease when a subject has developed vertigos with a history of fluctuating hearing with a loss of sensitivity to low-frequency, tinnitus and a feeling of fullness in the ear.
Frequently, the attack is announced with an increase in the intensity of the tinnitus and a heightened sensation of fullness of the ear and associated with a loss of hearing. The underlying anatomophysiological factor of this ailment is hydrops. It is a tear within the labyrinth due to an increase in the pressure of the endolymph. There are a number of signs associated with this disorder, so many that the disorder itself might be one of them. You simply have to remember this particular characteristic, knowing that the spontaneous nystagmus changes direction according to the inflation pressure of the membranous labyrinth. Physiotherapy for such an ailment is difficult and is only practiced by vestibular reeducation professionals with a substantial experience working with vertigo patients. The ENT community agrees that patients with Menière’s disease can not undergo reeducation. They are completely right in their belief but we are able to alleviate the symptoms, and make the subjects asymptomatic.
The brutal destruction of a peripheral organ is like a vertigo thunderstorm lasting several days. Often, the violence and the debilitating nature is such that patients are required to stay overnight at a hospital. After three days, the vertigos fade away but balance disorders persist. The source of the condition is viral and leads to paralysis of the vestibular nerve and the degree of recovery varies greatly. It is common to hear that neuritis is cured on its own. Doctors, when they are able to act immediately, administer corticoids. The varying degrees of recovery mean that in certain cases, patients do not spontaneously recover their balance. We believe that a subject who has not returned to normal social and professional life within two months is suitable for vestibular reeducation. There are other areas, such as the auricle that is associated with vertigo, deafness and facial paralysis.
Lastly, there are two bilateral disorders. Bilateral destruction is observed following antibiotic therapy for septicaemia or other infectious diseases that require long-term treatment. Antibiotics such as aminoglycasides have an acknowledged ototoxicity. It is obvious that in such cases, subjects affected are subjects with a life threatening condition, where a prescription of antibiotics is the only way to save their lives. Sometimes the therapist, when confronted with this type of illness also has to consider the protests of the subjects who have not weighed up the risks incurred. The product is not the issue: there are some priorities that one must know how to respect. The explanation would be the following: the product is above all nephrotoxic. The subject will be left with renal failure. Endolabyrinth clearance is slower than renal clearance. The product enters the labyrinth and initially, because of the ionic concentration, disrupts neurotransmission. Then, if the toxic product remains in the labyrinth for too long, the hair cells are destroyed. This means that the destruction, contrary to popular opinion, is not dependant. Conversely, it is certainly very useful, as far as prevention is concerned, to ensure how much elimination takes place through the urine. If the prescribing doctor agrees, it may be necessary to make them undergo a forced diuresis. For elderly patients, this is primarily referred to the orthopaedics department.
Now we have seen the most common peripheral pathologies, let us review the central pathologies. Broadly speaking, you could say that vertigo is a peripheral symptom. What we mean by this is that outside of Wallenberg’s syndrome, there are no central vertigos. Conversely, with imbalances, a variety of different balance disorders not presenting with vertigos are more likely to originate centrally. Central vestibular syndrome is not characterised by decreased responses but by a desinhibition of responses. Central syndromes are characterised by a certain disparity between the strength of the signs and the symptoms. It is not uncommon during the initial stages to find oneself face to face with a subject who is clearly suffering horribly even though the signs are less dramatic that those of a peripheral disorder. Besides degenerative disorders with the gradual onset of imbalance that later become real balance disorders, we see disorders with a sudden onset. There are, of course, brain stem strokes, whose signs are very indicative of the source of the infarction. And then there are all the TIAs, primarily from the vertebrobasilar region, with a spontaneous vertical nystagmus, but above all, the inability to get the patient into an upright position without generating a sensation of rocking or falling, together with cerebral pain, associated with a resolution of the muscular tonus. Given such scenarios, one can do no more than sense a deep respect for the discipline of neurology. The vestibular therapist will see their subject, in retrospect, when they are able to get around on their own or with the assistance of another person. As far as reeducation is concerned, as far as the treatment of a peripheral disorder is going to be invigorating and active, the treatment of patients with central disorders requires a great deal of care and attention, finesse, and listening closely to the patient. With vestibular reeducation, it is easier to worsen the condition of the patient rather than alleviate it.