Background to vestibular reeducation
At the end of the 1960s, J-M STERKERS used a new otoneurosurgical approach in order to carry out an exeresis of the vestibular schwannoma or to dissect the vestibular nerve in patients having developed a debilitating case of Ménière’s disease. Intracranial microsurgery was not a common practice at that time. Surgery of the posterior fossa which J-M S. excelled in is an exceptional surgery because of the very limited number of post-op after-effects compared to those from "macrosurgery".
The most visible after-effects were: facial paralysis and balance disorders. At that time, it should be stated, that tumours were quite large. We were at the very dawn of modern imaging, when it was for the most part non-existent. Balance disorders considerably slowed down social reinsertion.
J-M S. asked me to carry out reeducation on his post-op patients in order to allow them to return to a normal life as quickly as possible while decreasing the length of their hospital stay. The post-op patients did not suffer from any motor disorders that were comparable to patients with neurological disorders but they did suffer from a neurosensory disorder. The vestibular system, vestibular disorders, the physiology of vestibular interactions and the complaints of patients with vestibular disorders were not, and are not part of the curricular activities of a physiotherapist.
The only documents available, therefore, that dealt with this field were written by COOKSEY and CAWTHORNE. It dealt with group exercises with balls. The "game master", sitting in the middle of a circle of patients would throw the ball in a random direction to patients. There were also exercises involving the active movement of the head. We soon realised that the results obtained with patients who had been operated on were statistically scarcely different from those of a simple session of nursing.
J-M S. who was considerably advanced in his field at that time, seeing ballet dancers doing pirouettes and déboulés without making a mistake, in the end thought: we must do the same thing with patients. The idea was pure genius, and we will look at it in the following section, but it should be acknowledged that it is difficult to carry out. What J-M S. noted was that the dancers visually focused on a spot during three-quarters of their rotation. This was the secret. While turning, the subject watched a fixed visual reference point and found it again upon completion of the rotation, and so on. He had understood that visual fixation was the crucial element for maintaining balance. And this is how the rotation exercises with a focal point were conceived.
With this new situation, or rather, a situation where everything was still to do, a rigorous approach was required. One had to support the observations and actions with data from solid scientific experiments. Presenting a new technique without scientific references was both impossible and unthinkable. Thus the term vestibular reeducation (RV) was conceived. This was towards the end of the 1960s.
Initially, vestibular rehabilitation was post-op. The guiding principal was the following: get the subject into a state that is borderline debilitating and use the burden on the visual input to force the brain to control its responses. The term used at the time was "habituation". Habituation by the repetition of debilitating movements should also enable central compensation central by making use of substitution systems.
RV initially allowed us to decrease the length of the hospital stay. It enabled patients to quickly get back to work. Nowadays, it would be considered that the time was halved.
Next, we tried to re-educate pre-op patients to improve their post-op comfort. We were surprised to note that the following reeducation, patients required hardly any post-op VR. The difference was dependent, of course, on the condition of the vestibule in pre-op. It should be pointed out that at that point, it was the early 1970s and that otoneurological functional exploration was not what it is today.
Scientific validation of this work began thanks to the interest shown by scholar, A. BERTHOZ, towards neurosensory, and particularly vestibular matters in humans. His laboratory dealt with and still deals with perception, action and movement.
The encouraging results meant found ourselves obliged to open up vestibular rehabilitation to a wide range of patients: J-M S. had the great intellectual honesty to only operate on patients whose vestibular rehabilitation treatment had failed (excluding neuromas). Vestibular rehabilitation became a natural progression between medical treatment and surgery. Gradually, vestibular rehabilitation became the treatment, par excellence, of unsuccessful medial therapies. Then, in a rather more precise manner, a joint and complementary therapy to medical treatment for debilitating vestibular disorders. At the start, the decision taken made when the results from the medical treatment were considered insufficient or unsatisfactory. Later, the decision was taken when the consequences of the disorder on the social and professional life of the patient became too severe.
The "snow ball" effect of the induction in vestibular rehabilitation resulted in a confrontation in very specific cases, very rare cases. That is how a positional vertigo called BPPV, nowadays, thanks to its high visibility as "crystals", did not respond to VR. The only treatment available was VHT (vestibular habituation training) perfected by M. NORRE. The treatment consisted of repeating the provoked positions until the vertigo could no longer be reproduced. It should be acknowledged that not only was this treatment far from pleasant, but it also took a long time to get results. But there was nothing else available. A particular set of circumstances enabled A. Sémont to discover the "Liberation Manoeuvre". This proprietary therapeutic movement is comparable to the reduction manoeuvre for a dislocated joint. Access to scientific research allowed the author to validate the technique while understanding the potential consequences of this therapy. A thorough understanding of the mechanisms of the function of equilibration resulted in constant improvements to the techniques used in VR.
It is now the early 1980s. The internationalisation of vestibular rehabilitation began. There were numerous requests. I worked along side G. FREYSS. Thanks to the joint assistance of A. BERTHOZ, always loyal, and G. FREYSS, that point in time marked the start of a great period of clinical research, of verifying VR, and continually improving techniques.
Towards the end of the 1980s, the rotatory chair, the primary tool, was not enough. The hopes of helping patients who faced difficulties functioning in a three dimensional universe grew in importance. Surgical techniques were perfected and more importantly, therapeutic indications became more precise. The correspondents expected a great deal from VR. With the growth of expertise in the physiology of systems going hand in hand with the rise in processing power of computers, we entered a new domain: interaction with the environment. The Biodigital corporation believed in us and built the “planetarium” to provoke optokinetic stimulations in the full visual field. This very strong stimulus brought with certain alleviation in a yet unexplored fields: travel sickness, balance disorders associated with the elderly. At the same time, computerised dynamic posturography appeared in the US. Neurocom, a company founded by L. NASHNER, confided in me by manufacturing a posturography machine that was better adapted to VR. Smart was conceived, and enabled us not only to attend to patients but also to quantify the complaints of patients and monitor their treatment. We are therefore able to evaluate the technique, to specify the most responsive movements, to quantify the results of a treatment.
In 90, the idea was to teach, to transmit knowledge so that this technique would have longevity and could be of service to the greatest number of patients. A teaching team was created comprising G. FREYSS, E. VITTE, Ph. PERRIN, D. COUPEZ, Ph. COURTAT, N. JULIEN, J-L BENSIMON, D. BOUCCARA, O. STERKERS and J-P LAZARETH. A team that admittedly comprised ENT specialists, but also an anatomist, a neurologist, a neuro-radiologist, an audiologist, surgeons etc... All members of the teams boasted an international reputation. The training provided was of a very high quality. Many would begin but few would see it all the way through to the end.
The 1990s were taken up with teaching and conferences. In 1995, with the continued rise in processing power of computers, the appearance of specialised charts, the democratisation process, thanks to E. ULMER in France, of the use of miniature video cameras that provided a novel approach for observing eye movement. This enabled us to perfect a protocol for quantifying the function of the canalo-ocular reflex. Diagnosis apart, it enables us to carry out another form of monitoring during VR. We will be able to know, before each session, the degree of vestibular system dysfunction and therefore be more productive by carrying out the most appropriate action.