Adolescent idiopathic scoliosis (AIS) is characterised as a three-dimensional deformity of the spine with unknown etiopathogenesis. There is evidence that scoliosis may be associated with abnormalities of the vestibular system. Examination of postural stability and verticality perception is a way to assess vestibular function. The objective of this work is to compare postural stability and subjective visual vertical (SVV) between adolescents with idiopathic scoliosis and healthy controls. Twelve AIS patients and twelve controls participated in the study. Examination of postural stability was performed through a Kistler force platform and the SVV was tested using a pre-programmed computed equipment Synapsys. An instrument for evaluating the perception patients have of their trunk deformity, Trunk Appearance Perception Scale (TAPS), was also part of the examination. Our results did not show a significant difference between the two groups in postural stability and static SVV-S. Statistically significant difference was found on dynamic SVV-D with clockwise rotation (p  0,01): AIS patients (1,19ř ± 1,03ř), control group (-0,17ř ± 0,82ř). There was also a significant difference on absolute deviation of dynamic SVV-D with clockwise rotation (p  0,05): AIS patients (1,50ř ± 0,77ř), control group (0,81ř ±...

lateroflexion of 20 ř, after remaining 5 minutes in lateroflexion The mean deviation of the healthy population was measured at 1.26 ř ± 0.901. There ř ± 1.48) and subsequently a further increase in deviations when staying in this position (3.45 ř ± 3.15). The direction of SVV movement showed a more or less symmetrical distribution to the vestibular systém, head tilt, head

Introduction: Disorders of balance and dizziness are characteristic symptoms in patients after vestibular schwannoma surgery and often have a negative impact on their quality of life. This thesis deals with impairment of postural stability particularly in patients at the long time period after surgery. The aim of this study is to observe the longitudinal development of vestibular compensation from acute postoperative period to time of several years after surgery. Another aim is to evaluate the short-term effect of vestibular rehabilitation in a long time period after surgical treatment, and to compare the results of measuring the subjective visual vertical, posturography, score of the Dizziness Handicap Inventory questionnaire, age and tumor size in these patients. Methods: Examined group consisted of 10 patients after resection of vestibular schwannoma (mean age 41.4 ± 12.1 years; 2 women and 8 men). All patients underwent intensive rehabilitation program in the acute phase after surgery. 7 patients did exercise with visual feedback, and 3 patients had conventional rehabilitation without visual feedback. In long time period after surgery all patients underwent one exercise unit with visual feedback. Patients underwent computerized posturography examination using force platform Balance Master® in...

The thesis deals with the issues of balance disorders in patients after vestibular schwannoma surgery. The aim of this thesis is to evaluate the effect of targeted rehabilitation with biofeedback on balance disorders and subjective visual vertical compensation. During the period of one year, a group of 20 vestibular schwannoma patients were examined and treated in University Hospital Motol. The compensation of vestbuloocular refex was assessed by a tilt of subjective visual vertical. The level of vestibulospinal compensation was determined according to score of the Activities-Specific Balance Confidence Scale. Patients were examined before the surgery, after the surgery and after the rehabilitation. The Homebalance system, developed by Support center for application outputs and spin-off companies at the 1st Faculty of Medicine, Charles University in Prague, branch office in Kladno, was used for the therapy with visual biofeedback. Another aim of this thesis was to monitor the effect of vestibular prehabituation with ototoxic gentamicin application two months before surgery. The statistical analysis of data proved in the case of subjective visual vertical tilt a significant increase of deviation after surgery and a decrease after rehabilitation. According to the ABC questionnaire the confidence of...

This thesis deals with the evaluation of the vestibulo-ocular reflex in patients indicated for neurosurgical resection of vestibular schwannoma, executed at the Motol University Hospital. To evaluate the function of the vestibulo-ocular reflex, three types of clinical examinations were used. In periods before the surgery, early after the surgery and before leaving the hospital we monitored the patients' ability to perceive subjective visual vertical, which reflects tonic function of otolith organs. Before the surgery we also tested relative dynamic visual acuity during passive isolated head movements in the transversal plane, whose impairment is related to dysfunction of lateral semicircular canals. Furthermore, we obtained patients' preoperative values achieved in caloric reflex test. In the early postoperative period, bordered by the first day after the vestibular schwannoma surgery and the last day of the hospitalization, patients underwent specialized vestibular rehabilitation. Based on statistical analysis of acquired data, we found out that in some patients there was a lesion of the vestibulo-ocular reflex already before the surgery and moreover, there was a correlation between dysfunction of translational and rotational parts of the vestibulo-ocular reflex. Although variance of subjective...

In this thesis, we have been dealing with the evaluation of progressing of the postural stability in the patients after the operation of the vestibular schwannoma (VS). The stability was evaluated by means of stabilometric parameters (COP trajectory length, COP confidence ellipse area). We measured the development of the parameters before operation, immediately after resection and before the discharge. The set contained 17 patients (n = 17). The level of static importance we determined p ≤ 0,05. We found a statistically significant difference between the measurement before the operation and the measurement immediately after the operation (COP confidence ellipse area: p = 0,0183, COP trajectory length: p = 0,0355). On the other hand, the change in both parameters in the measurement before the discharge and the testing after the resection wasn't statistically significant (COP confidence ellipse area: p = 0,4081, COP trajectory length: p = 0,9991). Our next goal was to find out if the stability fault correlates with the disorder of function VOR. We testing the function of t-VOR by the subjective visual vertical (SVV) (n = 24), the function of the r-VOR by the dynamic visual acuity (DVA) (n = 28) and the caloric test (n = 21). We found a statistically significant correlation of both stabilometric...

Ce travail de thèse vise à évaluer le rôle des afférences cutanées plantaires dans le contrôle postural et oculomoteur en manipulant l’extéroception plantaire à l’aide de stimulations mécaniques plantaires fines. La 1ère étude a montré que des éléments médio-plantaires fins externes (EME) et surtout internes (EMI) améliorent la stabilité orthostatique et postériorisent le CPP de sujets jeunes et sains lors de mouvements des yeux. Ils ont aussi une action spécifique sur la vergence (pas sur les saccades) : les EMI augmentent l’amplitude phasique de divergence et diminuent la partie tonique, autrement dit agissent surtout sur la composante pré-programmée du mouvement ; alors que les EME agissent sur la convergence en augmentant son amplitude tonique, composante contrôlée sous influence de la rétroaction visuelle. Les inserts influent de manière directe sur le contrôle postural et oculomoteur par des voies spécifiques et indépendantes. La 2ème étude explique la variabilité des réponses des sujets de la 1ère. Nous avons mesuré leur degré d’utilisation des afférences extéroceptives plantaires par la méthode du Quotient Plantaire (QP = Surface CPP mousse / Surface CPP sol dur X 100). Un QP<100 suggère une Inefficience des Afférences Plantaires (IAP) : les sujets IAP ne présentent plus d’amélioration de leur stabilité ni aucune modification de la vergence avec les inserts plantaires. Nous proposons que cette situation soit non physiologique et relève d’un dysfonctionnement non douloureux latent des récepteurs plantaires, opposant les sujets IAP aux sujets ayant un QP normal. La 3ème étude a investigué les rapports entre l’utilisation des afférences plantaires et visuelles chez de jeunes adultes sains avec la méthode du QP et du Quotient du Romberg (QR). Elle mis en évidence l’existence d’une utilisation synergique des afférences visuelles et plantaires en vision de près, uniquement chez les sujets au QP normal. Les sujets IAP ont un QR plus bas que les sujets au QP normal, en vision de près et sur sol dur uniquement. Sur mousse, leur QR des sujets IAP augmente ; les yeux fermés, leur QP augmente, ce qui objective une asynergie visuo-podale. La 4ème étude, sur la même population, a montré qu’un EME bilatéral augmente l’esophorie, uniquement de loin et chez les sujets IAP. La 5ème étude a révélé l’influence de l’extéroception plantaire sur la perception de la Verticale Visuelle Subjective (VVS) sur la même population. Elle a montré une diminution de l’erreur vers la gauche de près chez les sujets au QP normal avec un EME droit, ainsi qu’une diminution de l’erreur absolue de loin chez les sujets IAP avec un EMI bilatéral. L’ensemble de ces travaux consolide au plan théorique l’importance des afférences plantaires aussi bien pour le contrôle orthostatique, le contrôle de la vergence, la perception de la VVS et l’alignement des yeux (phories). Ils démontrent que l’utilisation de ces afférences est variable selon les sujets et ont des implications cliniques pluridisciplinaires. / This thesis aims at assessing the role of plantar cutaneous afferents in postural and oculomotor control by manipulating plantar exteroception with thin mechanical plantar stimulations. The 1st study showed that lateral, and even more medial mid-foot plantar inserts (LAS / MAS) improve stability in quiet stance and induce a backward shift of the CoP of young healthy subjects during eye movements. They also have a specific action upon vergence (not saccades): MAS increase the phasic amplitude of divergence and decrease its tonic part, in other words they mainly act on the pre-programmed component of the movement; whereas LAS act upon convergence, increasing its tonic amplitude, which is under the influence of visual retroaction. The inserts have a direct influence upon postural and oculomotor control through specific and independent paths. The 2nd study explained the variability of the subjects’ answers of the former. We measured their degree of reliance upon plantar cutaneous afferents with the Plantar Quotient method (PQ = Surface CoP foam / Surface CoP firm gorund X 100). A PQ<100 suggest a Plantar Extercoeptive Inefficency (PEI): PEI subjects do not show any improvement of their stability or any modification of vergence with the inserts. We propose that this situation is non-physiological and results from a non-noxious latent dysfunction of the sole receptors, opposing the PEI subjects to those who have a normal PQ. The 3rd study investigated the relationship between the use of plantar and visual afferents in young healthy subjects with the method of the PQ and Romberg Quotient (RQ). It has evidenced the existence of a synergic use of visual and plantar afferents in close-distance vision, only among normal PQ subjects. The PEI subjects have a significantly lower RQ than the others only at close distance on firm ground. On foam, their RQ increases; eyes closed, their PQ increases, which objectifies a visual-podal asynergy. The 4th study, on the same population, showed that a bilateral LAS increase esophoria only at far distance and among the PEI subjects. The 5th study revealed the influence of plantar exteroception upon the perception of verticality on the same population. It has brought out a decrease of the leftward error at near distance among the normal PQ subjects with a right LAS, and a decrease of the absolute error at far distance among the PEI subjects with a bilateral MAS. Taken together, these studies support, from a theoretical point of view, the importance of plantar afferents for postural control as well as vergence control, SVV estimation and eyes alignment (phorias). They demonstrate that the use of these afferents depends on the subjects and have multidisciplinary clinical implications.