Book Summary: Recognized as two of the world's leading authorities on the subject, Susan Herdman and Richard Clendaniel, joined by a team of expert contributors, deliver the 4th Edition of the field's definitive text on the management of vestibular diseases and disorders. From assessment through therapy, they present the scientific and clinical knowledge you need to distinguish between vestibular and non-vestibular dizziness and to plan and implement the appropriate treatments.

The thesis deals with the issue of vestibular compensation in patiens after vestibular schwannoma surgery. The aim of this thesis was to objectively evaluate the dynamics of vestibular compensation in the early postoperative period and to determine whether the application of gentamicin impacts the dynamics of equilibrium functions. 32 patients participated in the study (20 women and 12 men) ranging from 28 to 73 years of age. Patients underwent a rehabilitation program with visual feedback using the interactive rehabilitation system, Homebalance. This rehabilitation program was carried out daily from the 5th postoperative day until hospital discharge. Patients were examined preoperatively, postoperatively and after rehabilitation. To assess the vestibular compensation, static posturography, the Synapsys Posturography System, and the Activities-Specific Balance Confidence Scale were used. The statistical analysis showed a significant increase in mean values of measured COP parameters (the length of the COP trajectory and COP confidence elipse area) postoperatively. After completing the rehabilitation program no significant reduction of measured COP parameters was found. The total score from the Activities- Specific Balance Confidence Scale showed a statistically significant decrease in postoperative...

Vestibular schwannoma surgery causes in majority of patients the unilateral peripheral or combined vestibular lesion due to surgical interruption of both branches of vestibular nerve. It manifests postoperatively with postural instability, vertigo, oscilopsia and even with vegetative symptoms. Central compensation, in which cerebellum plays dominant role, influences duration of the symptoms. Factors affecting compensation may be divided into several groups (general health status of a patient, the tumor itself, actual state of function of vestibular system, external factors induced by a therapeutist). Therapeutic aim is to induce compensatory mechanisms as soon as possible and to reduce overall duration of the compensation. The aim of this study is to consider predictive factors influencing central vestibular compensation and to influence the vestibular compensation itself. Early operated vestibular rehabilitation is a basic procedure. It leads to faster recovery in majority of patients. Even with maximal effort the full compensation is not always achieved. It results in permanent deficit of vestibular function manifested with postural instability. However in some patients it is difficult to achieve full compensation despite maximum effort of a physiotherapeutist and that results in permanent...

The aim of this thesis was to evaluate the effect of rehabilitation with visual biofeedback at acute stage after vestibular schwannoma surgery and to evaluate if preoperative intratympanic aplication of gentamicin has influence on vestibular compensation of standing stability. The study was attended by 20 patients (12 women and 8 men) in the age from 28 to 63 years. Eight patients had vestibular schwannoma diagnosed in their left side, twelve in the right side. Rehabilitation program using interactive rehabilitation system Homebalance took place from the 5th postoperative day until hospital discharge, daily 15 to 20 min. To evaluate of therapeutic intervention objectively the device Synapsys Posturography System was used. Stabilometric examination was done before operation of vestibular schwannoma, after operation and after termination of rehabilitation with visual biofeedback. Statistic analysis showed significant increase of mean values of measured parameters CoP (sway velocity CoP, length of trajectory of CoP, area of the confidence ellipse CoP) postoperatively compared to preoperative values. After termination of therapeutic intervention there was any significant decrease of values of parameters CoP compared to postoperative status. Between group of patients with preoperative aplication of...

The thesis deals with the evaluation of the impact of preoperative application of gentamicin on vestibular compensations of patient after vestibular schwannoma surgery. The trial involved 32 patients with diagnosed vestibular schwannoma and hospitalized with the indicated for neurosurgical resection at the University Hospital Motol. Ototoxic gentamicin was transtympanically applied to ten of these patients two months before their surgery. After the surgery the patients underwent a rehabilitation program based on the visual biofeedback using the Homebalance system. To evaluate the vestibular compensation the subjective visual vertical measurement and the Dynamic Gait Index standardized walking test were used. In total, each patient performed three examinations: before the surgery, after the surgery and before the end of hospitalization. Statistical analysis of the measured data showed the statistically significant increase tilt of subjective visual vertical and the decrease in the overall score of Dynamic Gait Index after surgery. Reduction in the subjective visual vertical tilt and the overall score of Dynamic Gait Index after rehabilitation has not been proven to be statistically significant. Any statistically significant difference was found between the group of patients treated by gentamicin and...

The human vestibulo-ocular reflex (VOR) stabilizes gaze during head movement. The reflex is typically tested in a clinic or laboratory using passive rotations or artificial stimuli which measure the amount of damage the vestibular apparatus has suffered. However, during everyday activities the vestibular system is stimulated by active, self generated head movements. Head movements are often rapid and associated with the goal of achieving either gaze-fixation or re-fixation. Patients who complain of on-going symptoms will typically identify a particular position or movement that aggravates their symptoms in their everyday life. There is a need to identify objective parameters which correlate with the subjective complaints of patients whose symptoms persist after vestibular damage. In the first study, a gaze-refixation task, patients who complain of ongoing symptoms (poorly-compensated), during rapid head turns, after unilateral vestibular de-afferentation (uVD) were compared with those who did not have the same complaints (well-compensated) and normal subjects. Well- and poorly-compensated groups were sorted according to responses on a standardized questionnaire. All subjects were then located in a real-world, non-laboratory environment in which poorly-compensated subjects reported experiencing symptoms. Each subject’s head, eye and gaze displacement and velocity, head rotation frequency and blink or eye-lid closure were measured and analysed and compared between ipsi- and contra-lesional head rotations within and between subject groups. When subjects are able to generate their own active head rotations it has been suggested that a number of vestibular and extra-vestibular strategies might be employed to compensate for an impaired VOR. In subsequent studies, high resolution scleral search coils were used to identify the compensatory mechanisms used during active head rotations during a gaze-fixation task. A corrective saccade is typically observed during passive ipsilesional head rotations or “impulses” and might be potentiated during rapid, active or self-generated head rotations. The conditions which predict or contribute to the generation of the rapid, corrective eye movement were investigated. The results were compared with responses to passive head impulses of matched velocity and acceleration to determine if active head impulses could be used to identify a lesioned vestibular apparatus as is routinely clinically achieved with passive head impulses.

The human vestibulo-ocular reflex (VOR) stabilizes gaze during head movement. The reflex is typically tested in a clinic or laboratory using passive rotations or artificial stimuli which measure the amount of damage the vestibular apparatus has suffered. However, during everyday activities the vestibular system is stimulated by active, self generated head movements. Head movements are often rapid and associated with the goal of achieving either gaze-fixation or re-fixation. Patients who complain of on-going symptoms will typically identify a particular position or movement that aggravates their symptoms in their everyday life. There is a need to identify objective parameters which correlate with the subjective complaints of patients whose symptoms persist after vestibular damage. In the first study, a gaze-refixation task, patients who complain of ongoing symptoms (poorly-compensated), during rapid head turns, after unilateral vestibular de-afferentation (uVD) were compared with those who did not have the same complaints (well-compensated) and normal subjects. Well- and poorly-compensated groups were sorted according to responses on a standardized questionnaire. All subjects were then located in a real-world, non-laboratory environment in which poorly-compensated subjects reported experiencing symptoms. Each subject’s head, eye and gaze displacement and velocity, head rotation frequency and blink or eye-lid closure were measured and analysed and compared between ipsi- and contra-lesional head rotations within and between subject groups. When subjects are able to generate their own active head rotations it has been suggested that a number of vestibular and extra-vestibular strategies might be employed to compensate for an impaired VOR. In subsequent studies, high resolution scleral search coils were used to identify the compensatory mechanisms used during active head rotations during a gaze-fixation task. A corrective saccade is typically observed during passive ipsilesional head rotations or “impulses” and might be potentiated during rapid, active or self-generated head rotations. The conditions which predict or contribute to the generation of the rapid, corrective eye movement were investigated. The results were compared with responses to passive head impulses of matched velocity and acceleration to determine if active head impulses could be used to identify a lesioned vestibular apparatus as is routinely clinically achieved with passive head impulses.

Made available in DSpace on 2016-06-02T20:18:07Z (GMT). No. of bitstreams: 1 TeseACPF.pdf: 1993727 bytes, checksum: 42770c78b76a4d455bc87403cef8c453 (MD5) Previous issue date: 2006-06-02 / The aim of this study was to verify the effects of histamine on the process of functional recovery after hemilabyrinthectomy in goldfish, Carassius auratus. To this end, the fish were submitted to unilateral vestibular lesion and treated with a histamine precursor (L-histidine) and antagonists of the receptors H1, H2 and H3 (respectively chlorpheniramine, zolantidine and thioperamide). The success of the surgery was evidenced by the ataxia they suffered during approximately thirty minutes of observation and the presence of these signs was used as criterion for the inclusion of the animal in the experiment. The subjects were treated during fifteen consecutive days with L-histidine (150 mg/kg), chlorpheniramine (24 mg/kg), zolantidine (18 mg/kg) and thioperamide (15 mg/kg). All substances were administrated in a volume of 1.5 ml/ kg of body weight and sterile saline (1.5 ml/kg) was used with the experimental control group. Another group, the sham lesion group, was submitted to the same surgical procedure, but in this case the vestibular lesion was not carried out. The subjects were submitted to seven tests, the first test being carried out on the first day after the lesion, and then five more at three day intervals. The seventh test was carried out three days after the conclusion of treatment. In each test, the subject was placed inside a translucent tube inside a black aquarium which was illuminated on the ipsilateral side for five minutes. The fish behavior was recorded with a video camera located in front of a small opening in the front wall of the aquarium. Body tilt was measured by comparing a line traced between the subject s eyes with a horizontal line traced on the television screen. The mean of the tilt in degrees obtained every thirty seconds was considered. The data were subjected to variance analysis (Two-way ANOVA), followed by the Student Newman Keuls multiple comparisons test. / O objetivo deste estudo foi verificar os efeitos da histamina sobre o processo de recuperação funcional, após hemilabirintectomia em peixes da espécie Carassius auratus. Para tanto, foram utilizados a L-histidina, um precursor histaminérgico e antagonistas dos receptores H1, H2 e H3, sendo a clorfeniramina, antagonista H1, a zolantidina antagonista H2 e a tioperamida, antagonista do receptor histaminérgico H3. Os peixes foram anestesiados e submetidos à lesão vestibular unilateral. O sucesso da cirurgia foi evidenciado pela ataxia, caracterizada pelo rolamento do corpo e nado incoordenado durante aproximadamente trinta minutos, e a presença desses sinais foi utilizada como critério de inclusão do animal no experimento. Os sujeitos foram tratados durante quinze dias consecutivos com L-histidina (150 mg/kg), clorfeniramina (24 mg/kg), zolantidina (18 mg/kg) e tioperamida (15 mg/kg). Todas as substâncias foram administradas em um volume de 1.5 ml/kg, e a salina estéril (1.5 ml/kg) foi utilizada como controle experimental. Um outro grupo foi submetido ao procedimento cirúrgico, mas a lesão vestibular não foi realizada (Lesão Fictícia). Os sujeitos foram submetidos a sete testes. O primeiro teste foi realizado no primeiro dia após a lesão, e os demais, a cada três dias, totalizando seis testes. O sétimo teste foi realizado três dias após o término do tratamento. Cada teste consistiu em posicionar o sujeito dentro de um cilindro, no interior de um aquário revestido com uma película preta e iluminar esse aquário no lado ipsilateral à lesão durante cinco minutos. O comportamento animal foi registrado através de uma câmera de vídeo posicionada em frente a uma pequena abertura presente na parede anterior do aquário. O ângulo de inclinação corporal foi formado por uma linha correspondente ao posicionamento dos olhos e uma linha horizontal e medido com um transferidor na tela do televisor. A média desses ângulos obtidos a cada trinta segundos foi considerada. Os dados foram analisados através da Análise de Variância (ANOVA) de duas vias, seguida do teste de comparações múltiplas de Student Newman Keuls.

Caffeine is one of the most popular psychostimulant drugs worldwide. Its effects are exerted through a variety of complex mechanisms, apparently primarily via interactions with adenosine A1 and A2A receptors. This drug has also been proven to elicit neuroprotective responses in a number of different brain disorders of the Central Nervous System (CNS), as well as provide enhancement of cognitive abilities. Moreover, a biphasic set of functional and structural neurological changes are often found in these receptors among diverse vertebrates. I investigated the effects of chronic caffeine exposure on functional recovery of the dorsal light reflex (DLR) in hemilabyrinthectomized common goldfish, Carassius auratus. In this lesion model the unilateral removal of vestibular organs results in the temporary loss of gravitational regulated postural control, which over time corrects itself by a vestibular compensation (VC) mechanism and can be quantified via the DLR. We compared the functional recovery over 24 post -surgery days in goldfish continuously held in a caffeine solution of 2.5mg/L (n=10), 5.0mg/L (n=10), 10.0mg/L (n=11) or a control 0.0mg/L (n=9). Compared to a sham surgery group (n=11), statistically significant changes in the DLR of all hemilabyrinthectomized goldfish was observed on day 1. The control group recovered over the study period by approaching but not entirely reaching sham surgery DLR. The 2.5mg/L and 5.0mg/L groups initiated postural recovery similar to the controls, but then regressed to a stronger DLR. Beginning on day 10 the caffeine groups deviated from the control and all three experimental caffeine groups were statistically different from the control group on days 15-24. Results suggest early caffeine exposure may be innocuous; however, chronic exposure inhibits the functional recovery process.

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...