Hydrops is characterised by a fluctuation of responses. We know that reflectivity varies according to the pressure of the inner ear. This imbalance of the responses is the element that fuels the critics when the following question is posed: "Can a patient with "Ménière’s disease" undergo reeducation?
Primarily the answer is a matter of semantics: is the term reeducation appropriate for the work of bringing symmetry to the responses of two vestibular systems? Of course not, because there are numerous phenomena responsible for the modification of responses and it is more readily an adaptation. As far as "Ménière’s disease" is concerned, once again one should be cautious given that experience has shown that all recurrent and fluctuating vestibular disorders labelled "Ménière’s" do not necessarily behave in the same way.
What name should one give to a recurrent disorder in a subject that appears in post-episode with a terrible nystagmus beating to the side of the hearing-impaired ear compared to one that also appears in post-episode, but manifests itself as a destructive nystagmus?
How do you label a subject who, following a rotatory chair session, has a crisis in the minutes that follow, and one who, after a rotatory chair session not only feels better, but recovers their hearing?
This is what makes it so difficult to treat these subjects.
- Can a patient with "Ménière syndrome” undergo reeducation": NO.
- Can one act upon the symptoms of "vertigo" and on the symptoms of "imbalance": YES.
It can be regarded that 60% of subjects suffering from pressure syndromes are medically very well controlled. The vestibular therapist treats the remaining 40%. Said percentage includes subjects who, if no vestibular therapist were available, would be eligible for surgical treatments of vertigo. We stay away from recommending surgery because medical treatment associated with reeducation can either avoid surgery, or schedule a surgery that is less finite than a neurectomy. It goes without saying that if results are non satisfactory or insufficient, surgery is recommended. Subjects labelled "Ménière" that we come across in reeducation are subjects who go through a phase of hyperactive vestibular response marked by debilitating attacks of vertigo that occur time and time again, sometimes several times a week. This group does not include elderly "Ménières" who only show signs of balance disorders or dizziness and who are treated as would any other patient with a unilateral vestibular deficit.
It is a very disparate group. There is no particular age group. They can only be classed into two categories:
- a younger group < 40 years of age whose condition appears very abruptly and is difficult to control.
- an older group > 40 years of age with a history of cochleovestibular issues that were believed to be under control, or even ended because hearing has become very bad (sic) with an increasing number of more frequent crises.
Correlation with serious emotional events or stress does not appear to be a very significant contributing factor. It is certain, on the other hand, that these subjects become acutely sensitive to any form of emotional or sensory attack. Conversely, the psycho-type of young subjects is relatively standard: uneasy, hyperactive and "nervous".
Without wanting to come to any foregone conclusions, experience shows us that the correctly labelled, young group is the easiest to treat because each subject follows quite a stereotypic protocol when the crisis appears and it therefore becomes quite easy to monitor the illness. The elderly group is more difficult to oversee.
All these subjects (> 40 years of age) have the following in common: recurrent rotatory vertigos with a vegetative neural cortex, an inability to stand up and to engage in any activities. They have a history of fluctuating hearing loss and tinnitus. When they come to reeducation, we see that the majority of them are wearing a hearing device. However the onset of the attack is not the same as that seen with young subjects. There is no longer the habitual increase in intensity of the tinnitus and hearing loss and the feeling of fullness of the ear that precedes the attack. We come across headaches, facial dysesthesia (normal imaging) vertigos that are not strictly rotatory but rather a combination of vertigo, dizziness, the sensation of falling, and visual disorders. There are no modifications to the tinnitus, hearing no longer fluctuates, the length of the attacks is variable, and distinguished by the terms minor crises and major crises. Medical treatment received is the same as that at the onset of the illness but with a significant increase in the prescribed amounts.
It would all appear to indicate a pressure syndrome of some kind but the ageing of the ailment is associated with a series of connected ailments that modify the symptoms, namely in how they are described, how they manifest themselves and their impact. This results in a "Ménière like" condition. With all these associated ailments, the most common are: migraines or similar, a transient ischemic attack of the vertebrobasilar region (very frequent for a population treated for hypertension).
The responses observed on a rotatory chair directly correlate to the state of pressure on the labyrinth. If we follow the mechanical hypothesis of TONNDORF, between crises the responses will be symmetrical or slightly hypo on the affected side. Hypovalence of the affected side is linked to the length of the illness. In pre-crisis, the affected ear will be severely hypo and in post-crisis, hyper. These three scenarios are resumed in the following table:
|Post crisis||Fixation||Circular Vection||Goggles|
|Clockwise rotation||14 seconds||15 seconds||18 jolts in 16 seconds|
|Anticlockwise rotation||30 seconds||35 seconds||25 jolts in 35 seconds|
|Between attacks||Fixation||Circular Vection||Goggles|
|Clockwise rotation||14 seconds||15 seconds||18 jolts in 15 seconds|
|Anticlockwise rotation||12 seconds||25 seconds||12 jolts in 15 seconds|
|Pre crisis||Fixation||Circular Vection||Goggles|
|Clockwise rotation||14 seconds||15 seconds||18 jolts in 16 seconds|
|Anticlockwise rotation||3 seconds||30 seconds||5 jolts in 10 seconds|
The particularity of these responses is that:
- Whatever the pressure, the response during circular vection of the affected ear is always greater than that of the healthy ear. It is as if the brain had maintained a hypersensibility to the sensation of rotation to the right, which is what the patient perceives during the crisis. The distortion of responses is only observed in pressure disorders of the inner ear.
The reeducation session consists of rotating the patient on the rotatory chair to decrease the response of the healthy ear so that response is similar to or even lower than that of the damaged ear. We begin with a series of three rotations (eyes closed during rotation). After a few sessions, this increases to five, then seven and sometimes ten, with fixation when the chair comes to a stop.
If we plot the values of the responses onto the graph after each series of rotations, we get a so-called adaptation curve that consists of the following sequences:
- an increased-response phase reflecting an increase in activity of the labyrinth,
- a fall in response reflecting an inhibition phase most likely originating in the cerebellum,
- a sharp rise in response reflecting an emission phenomena.
This increase is always accompanied by the appearance of nausea and other neuro-vegetative manifestations.
Fluctuations in the response of the affected ear oblige us to pay careful attention so as not to aggravate the symptoms of the subject. Schematically, we find ourselves in the following situation:
- the higher response is that of the healthy ear, in which case we can follow the norm whereby we repeat the rotations on the same side as the high levels of response in order to lower it.
- the too-high a response is that of the affected ear, in which case great care must be taken.
It is therefore important to know when the last crisis occurred:
- if it was very recent, then the rotatory chair at high speeds is counter indicative. It must be treated as if it were a central response.
- if the crisis is already a couple of days old and the gap between responses in the two directions is not excessive, then the rotatory chair can be used.
The session begins by rotating the subject symmetrically to observe responses of the affected ear.
There are two possible scenarios:
- the response of the affected ear only increases, in which case we stop and begin treating the central systems.
- the response falls until it is the same as the healthy ear, in which case we rotate asymmetrically to reduce the response of the healthy hear.
By repeating the sessions, we should see response times of less than five seconds for both sides, not only with five rotations, but with seven and ten too. A higher number of rotations serve no purpose. Between ten and twelve sessions are required with sessions scheduled twice a week for this result to be achieved. Then, the frequency of the sessions are decreased to check for the consistency of timing of responses and to monitor the affection. Treatment is stopped once the subject is asymptomatic for a period of time that exceeds the longest remission time experienced by the patient prior to treatment.
The ENT community shows itself to be a great deal more prudent when making a decision to "re-educate" a pressure syndrome. This perfectly warranted attitude stems from the fear of seeing the condition of the subject worsen through reeducation. It is not a question of a simply metaphysical anxiety but as a result of their experience. Providing care to these subjects is a delicate and difficult business. Having the full cooperation of the prescribing ENT is essential. Unfortunately, sometimes therapists, clearly with a desire to do the right thing, have really compounded the problems. Taking a step backwards is a difficult and drawn-out process. The role of a good therapist is to work quickly and well. Having to right the wrongs of incompetence takes away the whole purpose of the technique.
When everything goes smoothly, for a recurring disorder that does not respond to any rule, one must question the robustness of the action and the correlation between manoeuvre and result. The following questions can be posed:
How do we know if reeducation treatment is effective and if there is no spontaneous remission, as can be seen with this condition?
A number of facts call for the treatment:
- the fall in response from the rotatory chair session shows that "something is afoot ".
-subjects phone in because all the signs announcing the onset of an attack are there, and based on the experience of the patient, the attack is imminent. When the subject is tested on the chair, we observe that the response of the afflicted ear is hyper, as if the attack had already happened but with the subject not having experienced any symptoms of a vertigo. In the question and answer session, we learn that "over the past couple of days" they felt a bit unstable!
- sometimes when the attack happens, it does not last as long, it is less violent and above all, the prescribed medication that had no effect on the attacks of the past months, now appear to have an effect. As if there was a threshold after which point, nothing else works. "Reeducation" must have modified the threshold, explaining the inhibition capacity of the crisis and the medication once again having an effect.
One might wonder if the possibility offered by the rotatory chair to monitor the affliction might not allow us to lower the anxiogenicity of the symptoms and allow the "Ménière" sufferer to live a more relaxed life and in a more detached manner?
This hypothesis is by no means insignificant. The relationship between therapist and patient is important. But it is not enough to explain the fall and the retention of responses on the rotatory chair. It doesn’t explain why, in the middle of treatment, at home during an attack, the patient admits that by fixing their gaze on a target, they were able to "block out" the attack. While at the start of treatment, movement of the visual scene was such that they could not even find a target to focus on.
Through which procedures would "reeducation" be able to act on these attacks?
Retinal slip is an error signal that is controlled by the flocculus. The slow phase of the nystagmus provoked by the rotation of the chair gives the sensation of movement of the visual scene. This movement is similar to that of vertigo, but with a lower speed. The repetition of stimulations undoubtedly provokes, via the flocculus, an increase in their ability to inhibit retinal slip. The increase in the number of rotations exemplifies the capacity of the cerebellum to adapt to stimulations that are becoming more and more violent, until it is able to control the per-crisis nystagmus.
This is a hypothesis concerning the visual manifestation itself. The implementation of the adaptation, with changes to the thresholds would occur when reeducation is carried out during stable inter-crisis periods. Post-crisis reeducation would only be a kind of sedating action when compared to that obtained with subject with central-system disorders.
To conclude, the action of the vestibular therapist when treating this disorder brings the patient a certain peace of mind. Alleviating the symptoms generated by the illness but also the patient’s feeling of being alone. The therapist must make themselves available and be capable of attending to the patient if they fear dealing with a major event in their social and professional life. Observation of the nystagmus provides information whereby the therapist will be able to reassure the patient, or will be able to carry out a manoeuvre to enable them to overcome this difficult time. There is but one condition: to have the expertise, the experience, and the necessary competence to provide care for such a patient.