WorldWideScience

Sample records for vestibular function including

  1. Vestibular function testing.

    LENUS (Irish Health Repository)

    Lang, E E

    2010-06-01

    Vestibular symptoms of vertigo, dizziness and dysequilibrium are common complaints which can be disabling both physically and psychologically. Routine examination of the ear nose and throat and neurological system are often normal in these patients. An accurate history and thorough clinical examination can provide a diagnosis in the majority of patients. However, in a subgroup of patients, vestibular function testing may be invaluable in arriving at a correct diagnosis and ultimately in the optimal treatment of these patients.

  2. Aging of vestibular function evaluated using correlational vestibular autorotation test

    Directory of Open Access Journals (Sweden)

    Hsieh LC

    2014-09-01

    Full Text Available Li-Chun Hsieh,1,2 Hung-Ching Lin,2,3 Guo-She Lee4,5 1Institute of Brain Science, School of Medicine, National Yang-Ming University, Taipei, Taiwan; 2Department of Otolaryngology, Mackay Memorial Hospital, Taipei, Taiwan; 3Department of Audiology and Speech Language Pathology, Mackay Memorial Medical College, Taipei, Taiwan; 4Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; 5Department of Otolaryngology, Taipei City Hospital, Ren-Ai Branch, Taipei, Taiwan Background: Imbalance from degeneration of vestibular end organs is a common problem in the elderly. However, the decline of vestibular function with aging was revealed in few vestibular function tests such as vestibular autorotation test (VAT. In the current VAT, there are drawbacks of poor test–retest reliability, slippage of the sensor at high-speed rotations, and limited data about the effect of aging. We developed a correlational-VAT (cVAT system that included a small, light sensor (less than 20 g with wireless data transmission technique to evaluate the aging of vestibular function. Material and methods: We enrolled 53 healthy participants aged between 25 and 75 years and divided them into five age groups. The test conditions were vertical and horizontal head autorotations of frequencies from 0 to 3 Hz with closed eyes or open eyes. The cross-correlation coefficient (CCC between eye velocity and head velocity was obtained for the head autorotations between 1 Hz and 3 Hz. The mean of the CCCs was used to represent the vestibular function. Results: Age was significantly and negatively correlated with the mean CCC for all test conditions, including horizontal or vertical autorotations with open eyes or closed eyes (P<0.05. The mean CCC with open eyes declined significantly at 55–65 years old and the mean CCC with closed eyes declined significantly at 65–75 years old.Conclusion: Vestibular function evaluated using mean CCC revealed a decline with

  3. Dyscalculia and vestibular function.

    Science.gov (United States)

    Smith, P F

    2012-10-01

    A few studies in humans suggest that changes in stimulation of the balance organs of the inner ear (the 'vestibular system') can disrupt numerical cognition, resulting in 'dyscalculia', the inability to manipulate numbers. Many studies have also demonstrated that patients with vestibular dysfunction exhibit deficits in spatial memory. It is suggested that there may be a connection between spatial memory deficits resulting from vestibular dysfunction and the occurrence of dyscalculia, given the evidence that numerosity is coupled to the processing of spatial information (e.g., the 'spatial numerical association of response codes ('SNARC') effect'). The evidence supporting this hypothesis is summarised and potential experiments to test it are proposed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Perspectives on aging vestibular function

    Directory of Open Access Journals (Sweden)

    Eric eAnson

    2016-01-01

    Full Text Available Much is known about age related anatomical changes in the vestibular system. Knowledge regarding how vestibular anatomical changes impact behavior for older adults continues to grow, in line with advancements in diagnostic testing. However, despite advancements in clinical diagnostics, much remains unknown about the functional impact that an aging vestibular system has on daily life activities like standing and walking. Modern diagnostic tests are very good at characterizing neural activity of the isolated vestibular system, but the tests themselves are artificial and do not reflect the multi-sensory aspects of natural human behavior. Also, the majority of clinical diagnostic tests are passively applied because active behavior can enhance performance. In this perspective paper we review anatomical and behavioral changes associated with an aging vestibular system and highlight several areas where a more functionally relevant perspective can be taken. For postural control, a multi-sensory perturbation approach could be used to bring balance rehabilitation into the arena of precision medicine. For walking and complex gaze stability, this may result in less physiologically specific impairments, but the trade-off would be a greater understanding of how the aging vestibular system truly impacts the daily life of older adults.

  5. Perspectives on Aging Vestibular Function.

    Science.gov (United States)

    Anson, Eric; Jeka, John

    2015-01-01

    Much is known about age-related anatomical changes in the vestibular system. Knowledge regarding how vestibular anatomical changes impact behavior for older adults continues to grow, in line with advancements in diagnostic testing. However, despite advancements in clinical diagnostics, much remains unknown about the functional impact that an aging vestibular system has on daily life activities such as standing and walking. Modern diagnostic tests are very good at characterizing neural activity of the isolated vestibular system, but the tests themselves are artificial and do not reflect the multisensory aspects of natural human behavior. Also, the majority of clinical diagnostic tests are passively applied because active behavior can enhance performance. In this perspective paper, we review anatomical and behavioral changes associated with an aging vestibular system and highlight several areas where a more functionally relevant perspective can be taken. For postural control, a multisensory perturbation approach could be used to bring balance rehabilitation into the arena of precision medicine. For walking and complex gaze stability, this may result in less physiologically specific impairments, but the trade-off would be a greater understanding of how the aging vestibular system truly impacts the daily life of older adults.

  6. Perspectives on Aging Vestibular Function

    National Research Council Canada - National Science Library

    Anson, Eric; Jeka, John

    2016-01-01

    Much is known about age related anatomical changes in the vestibular system. Knowledge regarding how vestibular anatomical changes impact behavior for older adults continues to grow, in line with advancements in diagnostic testing...

  7. Vestibular Function and Activities of Daily Living

    Directory of Open Access Journals (Sweden)

    Aisha Harun MD

    2015-09-01

    Full Text Available Objective: Vestibular dysfunction increases with age and is associated with mobility difficulties and fall risk in older individuals. We evaluated whether vestibular function influences the ability to perform activities of daily living (ADLs. Method: We analyzed the 1999 to 2004 National Health and Nutrition Examination Survey of adults aged older than 40 years ( N = 5,017. Vestibular function was assessed with the Modified Romberg test. We evaluated the association between vestibular function and difficulty level in performing specific basic and instrumental ADLs, and total number of ADL impairments. Results: Vestibular dysfunction was associated with significantly higher odds of difficulty with nine ADLs, most strongly with difficulty managing finances (odds ratio [ OR ] = 2.64, 95% confidence interval [CI] = [1.18, 5.90]. In addition, vestibular dysfunction was associated with a significantly greater number of ADL impairments (β = .21, 95% CI = [0.09, 0.33]. This effect size was comparable with the influence of heavy smoking (β = .21, 95% CI = [0.06, 0.36] and hypertension (β = .10, 95% CI = [0.02, 0.18] on the number of ADL impairments. Conclusion: Vestibular dysfunction significantly influences ADL difficulty, most strongly with a cognitive rather than mobility-based task. These findings underscore the importance of vestibular inputs for both cognitive and physical daily activities.

  8. Recovery of Vestibular Ocular Reflex Function and Balance Control after a Unilateral Peripheral Vestibular Deficit

    OpenAIRE

    John eAllum

    2012-01-01

    This review describes the effect of unilateral peripheral vestibular deficit (UPVD) on balance control for stance and gait tests. Because a UPVD is normally defined based on vestibular ocular reflex (VOR) tests, we compared recovery observed in balance control with patterns of recovery in VOR function. Two general types of UPVD are considered; acute vestibular neuritis (AVN) and vestibular neurectomy. The latter was subdivided into vestibular loss after cerebellar pontine angle tumor surgery ...

  9. Interaction between Vestibular Compensation Mechanisms and Vestibular Rehabilitation Therapy: 10 Recommendations for Optimal Functional Recovery

    OpenAIRE

    Lacour, Michel; Bernard-Demanze, Laurence

    2015-01-01

    This review questions the relationships between the plastic events responsible for the recovery of vestibular function after a unilateral vestibular loss (vestibular compensation), which has been well described in animal models in the last decades, and the vestibular rehabilitation (VR) therapy elaborated on a more empirical basis for vestibular loss patients. The main objective is not to propose a catalog of results but to provide clinicians with an understandable view on when and how to per...

  10. Interaction between vestibular compensation mechanisms and vestibular rehabilitation therapy: ten recommendations for optimal functional recovery

    OpenAIRE

    LACOUR eMichel; BERNARD DEMANZE eLaurence

    2015-01-01

    This review questions the relationships between the plastic events responsible for the recovery of vestibular function after a unilateral vestibular loss (vestibular compensation), which has been well described in animal models in the last decades, and the vestibular rehabilitation (VR) therapy elaborated on a more empirical basis for vestibular loss patients. The main objective is not to propose a catalogue of results but to provide clinicians with an understandable view on when and how to p...

  11. Vestibular function assessment using the NIH Toolbox

    Science.gov (United States)

    Schubert, Michael C.; Whitney, Susan L.; Roberts, Dale; Redfern, Mark S.; Musolino, Mark C.; Roche, Jennica L.; Steed, Daniel P.; Corbin, Bree; Lin, Chia-Cheng; Marchetti, Greg F.; Beaumont, Jennifer; Carey, John P.; Shepard, Neil P.; Jacobson, Gary P.; Wrisley, Diane M.; Hoffman, Howard J.; Furman, Gabriel; Slotkin, Jerry

    2013-01-01

    Objective: Development of an easy to administer, low-cost test of vestibular function. Methods: Members of the NIH Toolbox Sensory Domain Vestibular, Vision, and Motor subdomain teams collaborated to identify 2 tests: 1) Dynamic Visual Acuity (DVA), and 2) the Balance Accelerometry Measure (BAM). Extensive work was completed to identify and develop appropriate software and hardware. More than 300 subjects between the ages of 3 and 85 years, with and without vestibular dysfunction, were recruited and tested. Currently accepted gold standard measures of static visual acuity, vestibular function, dynamic visual acuity, and balance were performed to determine validity. Repeat testing was performed to examine reliability. Results: The DVA and BAM tests are affordable and appropriate for use for individuals 3 through 85 years of age. The DVA had fair to good reliability (0.41–0.94) and sensitivity and specificity (50%–73%), depending on age and optotype chosen. The BAM test was moderately correlated with center of pressure (r = 0.42–0.48) and dynamic posturography (r = −0.48), depending on age and test condition. Both tests differentiated those with and without vestibular impairment and the young from the old. Each test was reliable. Conclusion: The newly created DVA test provides a valid measure of visual acuity with the head still and moving quickly. The novel BAM is a valid measure of balance. Both tests are sensitive to age-related changes and are able to screen for impairment of the vestibular system. PMID:23479540

  12. Vestibular function assessment using the NIH Toolbox.

    Science.gov (United States)

    Rine, Rosemarie M; Schubert, Michael C; Whitney, Susan L; Roberts, Dale; Redfern, Mark S; Musolino, Mark C; Roche, Jennica L; Steed, Daniel P; Corbin, Bree; Lin, Chia-Cheng; Marchetti, Greg F; Beaumont, Jennifer; Carey, John P; Shepard, Neil P; Jacobson, Gary P; Wrisley, Diane M; Hoffman, Howard J; Furman, Gabriel; Slotkin, Jerry

    2013-03-12

    Development of an easy to administer, low-cost test of vestibular function. Members of the NIH Toolbox Sensory Domain Vestibular, Vision, and Motor subdomain teams collaborated to identify 2 tests: 1) Dynamic Visual Acuity (DVA), and 2) the Balance Accelerometry Measure (BAM). Extensive work was completed to identify and develop appropriate software and hardware. More than 300 subjects between the ages of 3 and 85 years, with and without vestibular dysfunction, were recruited and tested. Currently accepted gold standard measures of static visual acuity, vestibular function, dynamic visual acuity, and balance were performed to determine validity. Repeat testing was performed to examine reliability. The DVA and BAM tests are affordable and appropriate for use for individuals 3 through 85 years of age. The DVA had fair to good reliability (0.41-0.94) and sensitivity and specificity (50%-73%), depending on age and optotype chosen. The BAM test was moderately correlated with center of pressure (r = 0.42-0.48) and dynamic posturography (r = -0.48), depending on age and test condition. Both tests differentiated those with and without vestibular impairment and the young from the old. Each test was reliable. The newly created DVA test provides a valid measure of visual acuity with the head still and moving quickly. The novel BAM is a valid measure of balance. Both tests are sensitive to age-related changes and are able to screen for impairment of the vestibular system.

  13. Replacing semicircular canal function with a vestibular implant.

    Science.gov (United States)

    Merfeld, Daniel M; Lewis, Richard F

    2012-10-01

    To summarize the recent progress in the development of vestibular implants. The review is timely because of the recent advances in the field and because MED-EL has recently announced that they are developing a vestibular implant for clinical applications. The handicap experienced by patients suffering from bilateral vestibulopathy has a strong negative impact on physical and social functioning that appears to justify a surgical intervention. Two different surgical approaches to insert electrodes to stimulate ampullary neurons have been shown to be viable. The three-dimensional vestibulo-ocular reflex in rhesus monkeys produced with a three-dimensional vestibular implant showed gains that were relatively normal during acute stimulation. Rotation cues provided by an implant interact with otolith cues in a qualitatively normal manner. The brain appears to adapt plastically to the cues provided via artificial electrical stimulation. Research to date includes just a few human studies, but available data from both humans and animals support the technological and physiological feasibility of vestibular implants. Although vestibular implant users should not expect normal vestibular function - any more than cochlear implant users should expect normal hearing - data suggest that significant functional improvements are possible.

  14. Symptomatic recovery in Miller Fisher Syndrome parallels vestibular-perceptual and not vestibular-ocular reflex function

    Directory of Open Access Journals (Sweden)

    Barry M Seemungal

    2011-02-01

    Full Text Available Unpleasant visual symptoms including oscillopsia and dizziness may occur when there is unexpected motion of the visual world across the subject’s retina (‘retinal-slip’ as in an acute spontaneous nystagmus or on head movement with an acute ophthalmoplegia. In contrast, subjects with chronic ocular dysmotility, e.g. congenital nystagmus or CPEO (chronic progressive external ophthalmoplegia, are typically symptom free. The adaptive processes that render chronic patients asymptomatic are obscure but may include a suppression of oscillopsia perception as well as an increased tolerance to perceived oscillopsia. Such chronic asymptomatic patients display an attenuation of vestibular-mediated angular velocity perception, implying a possible contributory role in the adaptive process. In order to assess causality between symptoms, signs (i.e. eye-movements and vestibular perceptual function, we prospectively assessed symptom ratings and ocular-motor and perceptual vestibular function, in a patient with acute but transient ophthalmoplegia due to Miller Fisher Syndrome (as a model of visuo-vestibular adaptation. The data show that perceptual measures of vestibular function display a significant attenuation as compared to ocularmotor measures during the acute, symptomatic period. Perhaps significantly, both symptomatic recovery and normalisation of vestibular perceptual function were delayed and then occurred in a parallel fashion. This is the first report showing that symptomatic recovery of visuo-vestibular symptoms is better paralleled by vestibular-perceptual testing than VOR (vestibular ocular reflex measures. The findings may have implications for the understanding of patients with chronic vestibular symptoms where VOR testing is often unhelpful.

  15. Improving Sensorimotor Function Using Stochastic Vestibular Stimulation

    Science.gov (United States)

    Galvan, R. C.; Clark, T. K.; Merfeld, D. M.; Bloomberg, J. J.; Mulavara, A. P.; Oman, C. M.

    2014-01-01

    Astronauts experience sensorimotor changes during spaceflight, particularly during G-transition phases. Post flight sensorimotor changes may include postural and gait instability, spatial disorientation, and visual performance decrements, all of which can degrade operational capabilities of the astronauts and endanger the crew. Crewmember safety would be improved if these detrimental effects of spaceflight could be mitigated by a sensorimotor countermeasure and even further if adaptation to baseline could be facilitated. The goal of this research is to investigate the potential use of stochastic vestibular stimulation (SVS) as a technology to improve sensorimotor function. We hypothesize that low levels of SVS will improve sensorimotor performance through stochastic resonance (SR). The SR phenomenon occurs when the response of a nonlinear system to a weak input signal is optimized by the application of a particular nonzero level of noise. Two studies have been initiated to investigate the beneficial effects and potential practical usage of SVS. In both studies, electrical vestibular stimulation is applied via electrodes on the mastoid processes using a constant current stimulator. The first study aims to determine the repeatability of the effect of vestibular stimulation on sensorimotor performance and perception in order to better understand the practical use of SVS. The beneficial effect of low levels of SVS on balance performance has been shown in the past. This research uses the same balance task repeated multiple times within a day and across days to study the repeatability of the stimulation effects. The balance test consists of 50 sec trials in which the subject stands with his or her feet together, arms crossed, and eyes closed on compliant foam. Varying levels of SVS, ranging from 0-700 micro A, are applied across different trials. The subject-specific optimal SVS level is that which results in the best balance performance as measured by inertial

  16. Vestibular involvement in cognition: Visuospatial ability, attention, executive function, and memory.

    Science.gov (United States)

    Bigelow, Robin T; Agrawal, Yuri

    2015-01-01

    A growing body of literature suggests the inner ear vestibular system has a substantial impact on cognitive function. The strongest evidence exists in connecting vestibular function to the cognitive domain of visuospatial ability, which includes spatial memory, navigation, mental rotation, and mental representation of three-dimensional space. Substantial evidence also exists suggesting the vestibular system has an impact on attention and cognitive processing ability. The cognitive domains of memory and executive function are also implicated in a number of studies. We will review the current literature, discuss possible causal links between vestibular dysfunction and cognitive performance, and suggest areas of future research.

  17. Physiological principles of vestibular function on earth and in space

    Science.gov (United States)

    Minor, L. B.

    1998-01-01

    Physiological mechanisms underlying vestibular function have important implications for our ability to understand, predict, and modify balance processes during and after spaceflight. The microgravity environment of space provides many unique opportunities for studying the effects of changes in gravitoinertial force on structure and function of the vestibular system. Investigations of basic vestibular physiology and of changes in reflexes occurring as a consequence of exposure to microgravity have important implications for diagnosis and treatment of vestibular disorders in human beings. This report reviews physiological principles underlying control of vestibular processes on earth and in space. Information is presented from a functional perspective with emphasis on signals arising from labyrinthine receptors. Changes induced by microgravity in linear acceleration detected by the vestibulo-ocular reflexes. Alterations of the functional requirements for postural control in space are described. Areas of direct correlation between studies of vestibular reflexes in microgravity and vestibular disorders in human beings are discussed.

  18. Receptors of glutamate and neurotrophin in vestibular neuronal functions.

    Science.gov (United States)

    Chan, Y S; Chen, L W; Lai, C H; Shum, D K Y; Yung, K K L; Zhang, F X

    2003-01-01

    The last decade has witnessed advances in understanding the roles of receptors of neurotrophin and glutamate in the vestibular system. In the first section of this review, the biological actions of neurotrophins and their receptors in the peripheral and central vestibular systems are summarized. Emphasis will be placed on the roles of neurotrophins in developmental plasticity and in the maintenance of vestibular function in the adult animal. This is reviewed in relation to the developmental expression pattern of neurotrophins and their receptors within the vestibular nuclei. The second part is focused on the functional role of different glutamate receptors on central vestibular neurons. The developmental expression pattern of glutamate receptor subunits within the vestibular nuclei is reviewed in relation to the potential role of glutamate receptors in regulating the development of vestibular function. Copyright 2003 National Science Council, ROC and S. Karger AG, Basel

  19. Recovery of vestibular ocular reflex function and balance control after a unilateral peripheral vestibular deficit.

    Directory of Open Access Journals (Sweden)

    John eAllum

    2012-05-01

    Full Text Available This review describes the effect of unilateral peripheral vestibular deficit (UPVD on balance control as observed in stance and gait tests. Normally, a UPVD is defined based on vestibular ocular reflex (VOR function. Therefore, we compare recovery observed in balance control over time with similar patterns of recovery or lack thereof in VOR function. Three types of UPVD are considered; acute vestibular neuritis, vestibular loss prior to and after cerebellar pontine angle tumor (CPAT surgery during which a vestibular neurectomy was performed, and vestibular loss following neurectomy to eliminate disabling Ménière’s disease.To measure balance control, body-worn gyroscopes, mounted near the body’s centre of mass, were used for stance and gait tests. Measurement variables were the pitch (anterior-posterior and roll (lateral sway angles and angular velocities of the lower trunk-pelvis. All three groups showed balance deficits during stance tasks on foam, especially with eyes closed when stable control is highly dependent on vestibular inputs. Deficits in balance control during gait were present but were more profound for complex gait tasks such as tandem gait. Differences emerged between the groups concerning the severity of the deficit and its recovery. Generally, the effects of acute neuritis were more severe but recovered rapidly, deficits due to vestibular neurectomy were less severe but longer lasting. These results paralleled deficits in VOR function and raise questions about two modes of neural plasticity occurring in the vestibular system following vestibular loss: one mode being the limited central compensation for the loss, and the second mode being some restoration of peripheral vestibular function. Future work will need to correlate deficits in balance control during stance and gait more exactly with VOR deficits and carefully consider the differences between insufficient central compensation compared to inadequate peripheral

  20. Vestibular function of patients with profound deafness related to GJB2 mutation.

    Science.gov (United States)

    Kasai, Misato; Hayashi, Chieri; Iizuka, Takashi; Inoshita, Ayako; Kamiya, Kazusaku; Okada, Hiroko; Nakajima, Yukinori; Kaga, Kimitaka; Ikeda, Katsuhisa

    2010-09-01

    GJB2 mutations are responsible not only for deafness but also for the occurrence of vestibular dysfunction. However, vestibular dysfunction tends to be unilateral and less severe in comparison with that of bilateral deafness. The correlation between the cochlear and vestibular end-organs suggests that some children with congenital deafness may have vestibular impairments. On the other hand, GJB2 gene mutations are the most common cause of nonsyndromic deafness. The vestibular function of patients with congenital deafness (CD), which is related to GJB2 gene mutation, remains to be elucidated. The purpose of this study was to analyze the relationship between GJB2 gene mutation and vestibular dysfunction in adults with CD. A total of 31 subjects, including 10 healthy volunteers and 21 patients with CD, were enrolled in the study. A hearing test and genetic analysis were performed. The vestibular evoked myogenic potentials (VEMPs) were measured and a caloric test was performed to assess the vestibular function. The percentage of vestibular dysfunction was then statistically analyzed. The hearing level of all CD patients demonstrated a severe to profound impairment. In seven CD patients, their hearing impairment was related to GJB2 mutation. Five of the seven patients with CD related to GJB2 mutation demonstrated abnormalities in one or both of the two tests. The percentage of vestibular dysfunction of the patients with CD related to GJB2 mutation was statistically higher than in patients with CD unrelated to GJB2 mutation and in healthy controls.

  1. Vestibular Function in the Temporal and Parietal Cortex: Distinct Velocity and Inertial Processing Pathways

    Directory of Open Access Journals (Sweden)

    Jocelyne eVentre-Dominey

    2014-07-01

    Full Text Available A number of behavioural and neuroimaging studies have reported converging data in favour of a cortical network for vestibular function, distributed between the temporo-parietal cortex and the prefrontal cortex in the primate. In this review, we focus on the role of the cerebral cortex in visuo-vestibular integration including the motion sensitive temporo-occipital areas i.e. the middle superior temporal area (MST and the parietal cortex. Indeed these two neighbouring cortical regions, though they both receive combined vestibular and visual information, have distinct implications in vestibular function. In sum, this review of the literature leads to the idea of two separate cortical vestibular sub-systems forming (1 a velocity pathway including MST and direct descending pathways on vestibular nuclei. As it receives well defined visual and vestibular velocity signals, this pathway is likely involved in heading perception and rapid top-down regulation of eye/head coordination and (2 an inertial processing pathway involving the parietal cortex in connection with the subcortical vestibular nuclei complex responsible for velocity storage integration. This vestibular cortical pathway would be implicated in high order multimodal integration and cognitive functions, including world space and self- referential processing.

  2. Vestibular function in the temporal and parietal cortex: distinct velocity and inertial processing pathways

    Science.gov (United States)

    Ventre-Dominey, Jocelyne

    2014-01-01

    A number of behavioral and neuroimaging studies have reported converging data in favor of a cortical network for vestibular function, distributed between the temporo-parietal cortex and the prefrontal cortex in the primate. In this review, we focus on the role of the cerebral cortex in visuo-vestibular integration including the motion sensitive temporo-occipital areas i.e., the middle superior temporal area (MST) and the parietal cortex. Indeed, these two neighboring cortical regions, though they both receive combined vestibular and visual information, have distinct implications in vestibular function. In sum, this review of the literature leads to the idea of two separate cortical vestibular sub-systems forming (1) a velocity pathway including MST and direct descending pathways on vestibular nuclei. As it receives well-defined visual and vestibular velocity signals, this pathway is likely involved in heading perception and rapid top-down regulation of eye/head coordination and (2) an inertial processing pathway involving the parietal cortex in connection with the subcortical vestibular nuclei complex responsible for velocity storage integration. This vestibular cortical pathway would be implicated in high-order multimodal integration and cognitive functions, including world space and self-referential processing. PMID:25071481

  3. From ear to uncertainty: Vestibular contributions to cognitive function.

    Directory of Open Access Journals (Sweden)

    Paul eSmith

    2013-11-01

    Full Text Available In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in spatial orientation. In this review we summarise the evidence that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans and critically evaluate the evidence that these deficits are not due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. We review the evidence that vestibular lesions affect head direction and place cells as well as the emerging evidence that artificial activation of the vestibular system, using galvanic vestibular stimulation, can modulate cognitive function.

  4. From ear to uncertainty: vestibular contributions to cognitive function.

    Science.gov (United States)

    Smith, Paul F; Zheng, Yiwen

    2013-11-26

    In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and neocortex play in spatial orientation. In this review we summarize the evidence that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans and critically evaluate the evidence that these deficits are not due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. We review the evidence that vestibular lesions affect head direction and place cells as well as the emerging evidence that artificial activation of the vestibular system, using galvanic vestibular stimulation (GVS), can modulate cognitive function.

  5. The effects of vestibular lesions on hippocampal function in rats.

    Science.gov (United States)

    Smith, Paul F; Horii, Arata; Russell, Noah; Bilkey, David K; Zheng, Yiwen; Liu, Ping; Kerr, D Steve; Darlington, Cynthia L

    2005-04-01

    Interest in interaction between the vestibular system and the hippocampus was stimulated by evidence that peripheral vestibular lesions could impair performance in learning and memory tasks requiring spatial information processing. By the 1990s, electrophysiological data were emerging that the brainstem vestibular nucleus complex (VNC) and the hippocampus were connected polysynaptically and that hippocampal place cells could respond to vestibular stimulation. The aim of this review is to summarise and critically evaluate research published in the last 5 years that has seen major progress in understanding the effects of vestibular damage on the hippocampus. In addition to new behavioural studies demonstrating that animals with vestibular lesions exhibit impairments in spatial memory tasks, electrophysiological studies have confirmed long-latency, polysynaptic pathways between the VNC and the hippocampus. Peripheral vestibular lesions have been shown to cause long-term changes in place cell function, hippocampal EEG activity and even CA1 field potentials in brain slices maintained in vitro. During the same period, neurochemical investigations have shown that some hippocampal subregions exhibit long-term changes in the expression of neuronal nitric oxide synthase, arginase I and II, and the NR1 and NR2A N-methyl-D-aspartate (NMDA) receptor subunits following peripheral vestibular damage. Despite the progress, a number of important issues remain to be resolved, such as the possible contribution of auditory damage associated with vestibular lesions, to the hippocampal effects observed. Furthermore, although these studies demonstrate that damage to the vestibular system does have a long-term impact on the electrophysiological and neurochemical function of the hippocampus, they do not indicate precisely how vestibular information might be used in hippocampal functions such as developing spatial representations of the environment. Understanding this will require detailed

  6. Interaction between vestibular compensation mechanisms and vestibular rehabilitation therapy: ten recommendations for optimal functional recovery

    Directory of Open Access Journals (Sweden)

    LACOUR eMichel

    2015-01-01

    Full Text Available This review questions the relationships between the plastic events responsible for the recovery of vestibular function after a unilateral vestibular loss (vestibular compensation, which has been well described in animal models in the last decades, and the vestibular rehabilitation (VR therapy elaborated on a more empirical basis for vestibular loss patients. The main objective is not to propose a catalogue of results but to provide clinicians with an understandable view on when and how to perform VR therapy, and why VR may benefit from basic knowledge and may influence the recovery process. With this perspective, 10 major recommendations are proposed as ways to identify an optimal functional recovery. Among them are the crucial role of active and early VR therapy, coincidental with a post-lesion sensitive period for neuronal network remodelling, the instructive role that VR therapy may play in this functional reorganisation, the need for progression in the VR therapy protocol, which is based mainly on adaptation processes, the necessity to take into account the sensorimotor, cognitive and emotional profile of the patient to propose individual or à la carte VR therapies, and the importance of motivational and ecologic contexts. More than 10 general principles are very likely, but these principles seem crucial for the fast recovery of vestibular loss patients to ensure good quality of life.

  7. Interaction between Vestibular Compensation Mechanisms and Vestibular Rehabilitation Therapy: 10 Recommendations for Optimal Functional Recovery.

    Science.gov (United States)

    Lacour, Michel; Bernard-Demanze, Laurence

    2014-01-01

    This review questions the relationships between the plastic events responsible for the recovery of vestibular function after a unilateral vestibular loss (vestibular compensation), which has been well described in animal models in the last decades, and the vestibular rehabilitation (VR) therapy elaborated on a more empirical basis for vestibular loss patients. The main objective is not to propose a catalog of results but to provide clinicians with an understandable view on when and how to perform VR therapy, and why VR may benefit from basic knowledge and may influence the recovery process. With this perspective, 10 major recommendations are proposed as ways to identify an optimal functional recovery. Among them are the crucial role of active and early VR therapy, coincidental with a post-lesion sensitive period for neuronal network remodeling, the instructive role that VR therapy may play in this functional reorganization, the need for progression in the VR therapy protocol, which is based mainly on adaptation processes, the necessity to take into account the sensorimotor, cognitive, and emotional profile of the patient to propose individual or "à la carte" VR therapies, and the importance of motivational and ecologic contexts. More than 10 general principles are very likely, but these principles seem crucial for the fast recovery of vestibular loss patients to ensure good quality of life.

  8. Functional and anatomic alterations in the gentamicin-damaged vestibular system in the guinea pig

    NARCIS (Netherlands)

    Oei, MLYM; Segenhout, HM; Dijk, T; Stokroos, [No Value; van der Want, TJL; Albers, FWJ

    Hypothesis: The purpose of this study was to investigate the expected functional and morphologic effect of gentamicin on the vestibular system simultaneously by measurement of vestibular evoked potentials and electron microscopic evaluation. Background: Vestibular short-latency evoked potentials to

  9. Association Between Visuospatial Ability and Vestibular Function in the Baltimore Longitudinal Study of Aging.

    Science.gov (United States)

    Bigelow, Robin T; Semenov, Yevgeniy R; Trevino, Carolina; Ferrucci, Luigi; Resnick, Susan M; Simonsick, Eleanor M; Xue, Qian-Li; Agrawal, Yuri

    2015-09-01

    To investigate the relationship between vestibular loss associated with aging and age-related decline in visuospatial function. Cross-sectional analysis within a prospective cohort study. Baltimore Longitudinal Study of Aging (BLSA). Community-dwelling BLSA participants with a mean age of 72 (range 26-91) (N = 183). Vestibular function was measured using vestibular-evoked myogenic potentials. Visuospatial cognitive tests included Card Rotations, Purdue Pegboard, Benton Visual Retention Test, and Trail-Making Test Parts A and B. Tests of executive function, memory, and attention were also considered. Participants underwent vestibular and cognitive function testing. In multiple linear regression analyses, poorer vestibular function was associated with poorer performance on Card Rotations (P = .001), Purdue Pegboard (P = .005), Benton Visual Retention Test (P = 0.008), and Trail-Making Test Part B (P = .04). Performance on tests of executive function and verbal memory were not significantly associated with vestibular function. Exploratory factor analyses in a subgroup of participants who underwent all cognitive tests identified three latent cognitive abilities: visuospatial ability, verbal memory, and working memory and attention. Vestibular loss was significantly associated with lower visuospatial and working memory and attention factor scores. Significant consistent associations between vestibular function and tests of visuospatial ability were observed in a sample of community-dwelling adults. Impairment in visuospatial skills is often one of the first signs of dementia and Alzheimer's disease. Further longitudinal studies are needed to evaluate whether the relationship between vestibular function and visuospatial ability is causal. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

  10. Vestibular Function and Depersonalization/Derealization Symptoms.

    Science.gov (United States)

    Jáuregui Renaud, Kathrine

    2015-01-01

    Patients with an acquired sensory dysfunction may experience symptoms of detachment from self or from the environment, which are related primarily to nonspecific symptoms of common mental disorders and secondarily, to the specific sensory dysfunction. This is consistent with the proposal that sensory dysfunction could provoke distress and a discrepancy between the multi-sensory frame given by experience and the actual perception. Both vestibular stimuli and vestibular dysfunction can underlie unreal experiences. Vestibular afferents provide a frame of reference (linear and angular head acceleration) within which spatial information from other senses is interpreted. This paper reviews evidence that symptoms of depersonalization/derealization associated with vestibular dysfunction are a consequence of a sensory mismatch between disordered vestibular input and other sensory signals of orientation.

  11. Altered auditory and vestibular functioning in individuals with low bone mineral density: a systematic review.

    Science.gov (United States)

    Singh, Niraj Kumar; Jha, Raghav Hira; Gargeshwari, Aditi; Kumar, Prawin

    2018-01-01

    Alteration in the process of bone remodelling is associated with falls and fractures due to increased bone fragility and altered calcium functioning. The auditory system consists of skeletal structures and is, therefore, prone to getting affected by altered bone remodelling. In addition, the vestibule consists of huge volumes of calcium (CaCO3) in the form of otoconia crystals and alteration in functioning calcium levels could, therefore, result in vestibular symptoms. Thus, the present study aimed at compiling information from various studies on assessment of auditory or vestibular systems in individuals with reduced bone mineral density (BMD). A total of 1977 articles were searched using various databases and 19 full-length articles which reported auditory and vestibular outcomes in persons with low BMD were reviewed. An intricate relationship between altered BMD and audio-vestibular function was evident from the studies; nonetheless, how one aspect of hearing or balance affects the other is not clear. Significant effect of reduced bone mineral density could probably be due to the metabolic changes at the level of cochlea, secondary to alterations in BMD. One could also conclude that sympathetic remodelling is associated with vestibular problems in individual; however, whether vestibular problems lead to altered BMD cannot be ascertained with confidence. The studies reviewed in the article provide an evidence of possible involvement of hearing and vestibular system abnormalities in individuals with reduced bone mineral density. Hence, the assessment protocol for these individuals must include hearing and balance evaluation as mandatory for planning appropriate management.

  12. Evaluation of vestibular function in patients with chronic suppurative otitis media.

    Science.gov (United States)

    Mostafa, Badr Eldin; Shafik, Amr Gouda; El Makhzangy, Aly M N; Taha, Hesham; Abdel Mageed, Heba Mahmoud

    2013-01-01

    The objective of this study was to assess vestibular functions in patients with chronic suppurative otitis media (CSOM) with and without sensorineural hearing loss. This was a prospective case study performed at a tertiary referral university hospital. Sixty patients with CSOM were included, and patients with a history of head trauma, diabetes, hypertension, previous ear surgery, use of ototoxic drugs, neurological deficits and suspected fistulae were excluded. The patients underwent basic audiological evaluation, and clinical and instrumental vestibular evaluation. The incidence and extent of vestibular dysfunction in patients with CSOM were analyzed. A total of 42 males and 16 females with a mean age of 29.5 years were included in this study. Forty ears had tubotympanic disease and 19 had cholesteatoma. There were 14 ears with sensorineural hearing loss. A positive history of vertigo was reported in 53.5% of the cases. Rotatory chair abnormalities were found in 70% of the cases, caloric hypofunction was found in 61.6%, and vestibular myogenic evoked potentials were abnormal in 25%. The only positive correlation with vestibular dysfunction was the duration of disease. The vestibular system is significantly affected in cases with CSOM. Both semicircular canals and the saccule are affected. All patients with long-standing CSOM should be evaluated for vestibular dysfunction irrespective of their hearing levels. © 2014 S. Karger AG, Basel.

  13. Vestibular contributions to high-level sensorimotor functions.

    Science.gov (United States)

    Medendorp, W Pieter; Selen, Luc J P

    2017-10-01

    The vestibular system, which detects motion and orientation of the head in space, is known to be important in controlling gaze to stabilize vision, to ensure postural stability and to provide our sense of self-motion. While the brain's computations underlying these functions are extensively studied, the role of the vestibular system in higher level sensorimotor functions is less clear. This review covers new research on the vestibular influence on perceptual judgments, motor decisions, and the ability to learn multiple motor actions. Guided by concepts such as optimization, inference, estimation and control, we focus on how the brain determines causal relationships between memorized and visual representations in the updating of visual space, and how vestibular, visual and efferent motor information are integrated in the estimation of body motion. We also discuss evidence that these computations involve multiple coordinate representations, some of which can be probed in parietal cortex using neuronal oscillations derived from EEG. In addition, we describe work on decision making during self-motion, showing a clear modulation of bottom-up acceleration signals on decisions in the saccadic system. Finally, we consider the importance of vestibular signals as contextual cues in motor learning and recall. Taken together, these results emphasize the impact of vestibular information on high-level sensorimotor functions, and identify future directions for theoretical, behavioral, and neurophysiological investigations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Effect of low level laser (LLL) on cochlear and vestibular inner ear including tinnitus

    Science.gov (United States)

    Rhee, Chung-Ku; Lim, Eun-Seok; Kim, Young-Saeng; Chung, Yong-Won; Jung, Jae-Yun; Chung, Phil-Sang

    2006-02-01

    Objectives: 1. To investigate preventive effect of LLL on gentamicin-induced vestibular ototoxicity. 2. To evaluate the effectiveness of lower level laser (LLL) in the treatment of tinnitus. Methods: 1. Twenty guinea pigs were divided into control and laser groups. Vestibular ototoxicity was induced by intratympanic injection of gentamicin into left ear. LLL was irradiated into left ear canal of animals in laser group. Vestibular function of the animals was evaluated with vertical and off-vertical axis rotation testing. 2. Forty patients with tinnitus were treated with ginkgo biloba orally and randomly divided into control and laser groups. The 20 patients of laser group received 80.4 J/cm2 of 830 nm laser, 3 times per week for 4 weeks, via transmeatal irradiation. Tinnitus was evaluated by visual analogue scale (VAS) and tinnitus handicap inventory (THI). Results: 1. Preventive effect of LLL to gentamicin induced vestibular ototoxicity was demonstrated by preventing reduction of gain in slow harmonic acceleration test and modulation in the off-vertical axis rotation test. 2. Eleven of 20 laser group patients have shown significant improvement in VAS and THI compared to those of the control group. Conclusions: 1. LLL therapy may have preventive effect to vestibular ototoxicity. 2. LLL therapy in combination with ginkgo biloba seems to be worth trying on patients with tinnitus.

  15. Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

    Science.gov (United States)

    Noohi, F.; Kinnaird, C.; Wood, S.; Bloomberg, J.; Mulavara, A.; Seidler, R.

    2016-01-01

    The current study characterizes brain activation in response to two modes of vestibular stimulation: skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit either the vestibulo-spinal reflex (saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)), or the ocular muscle response (utricle-mediated ocular VEMP (oVEMP)). Some researchers have reported that air-conducted skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for the subjects. However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of cortical activity. Both forms of stimulation target the otolith response, which provides a measurement of vestibular function independent from semicircular canals. This is of high importance for studying otolith-specific deficits, including gait and balance problems that astronauts experience upon returning to earth. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that skull taps elicit similar patterns of cortical activity as the auditory tone bursts, and previous vestibular imaging studies. Subjects wore bilateral MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in the supine position, with eyes closed. Subjects received both forms of the stimulation in a counterbalanced fashion. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular system, resulting in the vestibular cortical response. Auditory tone bursts were also delivered for comparison. To validate our stimulation method, we measured the ocular VEMP outside of the scanner. This measurement showed that both skull tap and auditory

  16. Improving Sensorimotor Function and Adaptation using Stochastic Vestibular Stimulation

    Science.gov (United States)

    Galvan, R. C.; Bloomberg, J. J.; Mulavara, A. P.; Clark, T. K.; Merfeld, D. M.; Oman, C. M.

    2014-01-01

    Astronauts experience sensorimotor changes during adaption to G-transitions that occur when entering and exiting microgravity. Post space flight, these sensorimotor disturbances can include postural and gait instability, visual performance changes, manual control disruptions, spatial disorientation, and motion sickness, all of which can hinder the operational capabilities of the astronauts. Crewmember safety would be significantly increased if sensorimotor changes brought on by gravitational changes could be mitigated and adaptation could be facilitated. The goal of this research is to investigate and develop the use of electrical stochastic vestibular stimulation (SVS) as a countermeasure to augment sensorimotor function and facilitate adaptation. For this project, SVS will be applied via electrodes on the mastoid processes at imperceptible amplitude levels. We hypothesize that SVS will improve sensorimotor performance through the phenomena of stochastic resonance, which occurs when the response of a nonlinear system to a weak input signal is optimized by the application of a particular nonzero level of noise. In line with the theory of stochastic resonance, a specific optimal level of SVS will be found and tested for each subject [1]. Three experiments are planned to investigate the use of SVS in sensory-dependent tasks and performance. The first experiment will aim to demonstrate stochastic resonance in the vestibular system through perception based motion recognition thresholds obtained using a 6-degree of freedom Stewart platform in the Jenks Vestibular Laboratory at Massachusetts Eye and Ear Infirmary. A range of SVS amplitudes will be applied to each subject and the subjectspecific optimal SVS level will be identified as that which results in the lowest motion recognition threshold, through previously established, well developed methods [2,3,4]. The second experiment will investigate the use of optimal SVS in facilitating sensorimotor adaptation to system

  17. Vestibular contributions to high-level sensorimotor functions

    NARCIS (Netherlands)

    Medendorp, W.P.; Selen, L.P.J.

    2017-01-01

    The vestibular system, which detects motion and orientation of the head in space, is known to be important in controlling gaze to stabilize vision, to ensure postural stability and to provide our sense of self-motion. While the brain's computations underlying these functions are extensively studied,

  18. Vestibular mechanisms.

    Science.gov (United States)

    Precht, W

    1979-01-01

    It is apparent from this and other reviews of the subject that our knowledge of vestibular function is most complete for the primary canal and otolithic afferents. Relatively little progress has been made in the understanding of receptor mechanisms and the functional importance of the efferent vestibular system. Since most of it has been summarized previously the latter were not considered here. Considerably more knowledge has accumulated in the field of central vestibular mechanisms, particularly those related to eye movements. Recent advances in functional synaptology of direct and indirect vestibuloocular pathways are described. It appears that the indirect pathways are essential for the central integration of the peripheral head velocity into a central eye position signal. Candidates for the neural integrator are presented and discussed and their connectivity described both for the horizontal and the relatively poorly studied vertical eye movement system. This field will certainly be studied extensively during the next years. Another interesting field is the role of the cerebellum in the control the vestibuloocular reflex. Recent data and hypotheses, including the problem of cerebellar plasticity, are summarized and evaluated. That the vestibular nuclei are by no means a simple relay system for specific vestibular signals destined for other sensory or motor centers is evidenced in this review by the description of multiple canal-canal, canalotolith, and visual-vestibular convergence at the nuclear level. Canal-otolith and polysensory convergence in vestibular neurons enables them to correct for the inherent inadequacies of the peripheral canal system in the low frequency range. The mechanisms of polysensory interaction in the central vestibular system will undoubtedly be an important and interesting field for future research.

  19. Effects of conventional versus multimodal vestibular rehabilitation on functional capacity and balance control in older people with chronic dizziness from vestibular disorders: design of a randomized clinical trial.

    Science.gov (United States)

    Aquaroni Ricci, Natalia; Aratani, Mayra Cristina; Caovilla, Heloisa Helena; Freitas Ganança, Fernando

    2012-12-31

    There are several protocols designed to treat vestibular disorders that focus on habituation, substitution, adaptation, and compensation exercises. However, protocols that contemplate not only vestibular stimulation but also other components that are essential to the body balance control in older people are rare. This study aims to compare the effectiveness of two vestibular rehabilitation protocols (conventional versus multimodal) on the functional capacity and body balance control of older people with chronic dizziness due to vestibular disorders. A randomized, single-blind, controlled clinical trial with a 3 months follow-up period will be performed. The sample will be composed of older individuals with a clinical diagnosis of chronic dizziness resulting from vestibular disorders. The subjects will be evaluated at baseline, post-treatment and follow-up. Primary outcomes will be determined in accordance with the Dizziness Handicap Inventory (functional capacity) and the Dynamic Gait Index (body balance). Secondary outcomes include dizziness features, functional records, body balance control tests, and psychological information. The older individuals (minimum sample n = 68) will be randomized to either the conventional or multimodal Cawthorne&Cooksey protocols. The protocols will be performed during individual 50-minute sessions, twice a week, for 2 months (a total of 16 sessions). The outcomes of both protocols will be compared according to the intention-to-treat analysis. Vestibular rehabilitation through the Cawthorne&Cooksey protocol has already proved to be effective. However, the addition of other components related to body balance control has been proposed to improve the rehabilitation of older people with chronic dizziness from vestibular disorders. ACTRN12610000018011.

  20. Effects of conventional versus multimodal vestibular rehabilitation on functional capacity and balance control in older people with chronic dizziness from vestibular disorders: design of a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Ricci Natalia

    2012-12-01

    Full Text Available Abstract Background There are several protocols designed to treat vestibular disorders that focus on habituation, substitution, adaptation, and compensation exercises. However, protocols that contemplate not only vestibular stimulation but also other components that are essential to the body balance control in older people are rare. This study aims to compare the effectiveness of two vestibular rehabilitation protocols (conventional versus multimodal on the functional capacity and body balance control of older people with chronic dizziness due to vestibular disorders. Methods/design A randomized, single-blind, controlled clinical trial with a 3 months follow-up period will be performed. The sample will be composed of older individuals with a clinical diagnosis of chronic dizziness resulting from vestibular disorders. The subjects will be evaluated at baseline, post-treatment and follow-up. Primary outcomes will be determined in accordance with the Dizziness Handicap Inventory (functional capacity and the Dynamic Gait Index (body balance. Secondary outcomes include dizziness features, functional records, body balance control tests, and psychological information. The older individuals (minimum sample n = 68 will be randomized to either the conventional or multimodal Cawthorne&Cooksey protocols. The protocols will be performed during individual 50-minute sessions, twice a week, for 2 months (a total of 16 sessions. The outcomes of both protocols will be compared according to the intention-to-treat analysis. Discussion Vestibular rehabilitation through the Cawthorne&Cooksey protocol has already proved to be effective. However, the addition of other components related to body balance control has been proposed to improve the rehabilitation of older people with chronic dizziness from vestibular disorders. Trial registration ACTRN12610000018011

  1. Vestibular migraine

    DEFF Research Database (Denmark)

    Lempert, Thomas; Olesen, Jes; Furman, Joseph

    2012-01-01

    This paper presents diagnostic criteria for vestibular migraine, jointly formulated by the Committee for Classification of Vestibular Disorders of the Bárány Society and the Migraine Classification Subcommittee of the International Headache Society (IHS). The classification includes vestibular...... migraine and probable vestibular migraine. Vestibular migraine will appear in an appendix of the third edition of the International Classification of Headache Disorders (ICHD) as a first step for new entities, in accordance with the usual IHS procedures. Probable vestibular migraine may be included...... in a later version of the ICHD, when further evidence has been accumulated. The diagnosis of vestibular migraine is based on recurrent vestibular symptoms, a history of migraine, a temporal association between vestibular symptoms and migraine symptoms and exclusion of other causes of vestibular symptoms...

  2. Sustained and Transient Vestibular Systems: A Physiological Basis for Interpreting Vestibular Function.

    Science.gov (United States)

    Curthoys, Ian S; MacDougall, Hamish G; Vidal, Pierre-Paul; de Waele, Catherine

    2017-01-01

    Otolithic afferents with regular resting discharge respond to gravity or low-frequency linear accelerations, and we term these the static or sustained otolithic system. However, in the otolithic sense organs, there is anatomical differentiation across the maculae and corresponding physiological differentiation. A specialized band of receptors called the striola consists of mainly type I receptors whose hair bundles are weakly tethered to the overlying otolithic membrane. The afferent neurons, which form calyx synapses on type I striolar receptors, have irregular resting discharge and have low thresholds to high frequency (e.g., 500 Hz) bone-conducted vibration and air-conducted sound. High-frequency sound and vibration likely causes fluid displacement which deflects the weakly tethered hair bundles of the very fast type I receptors. Irregular vestibular afferents show phase locking, similar to cochlear afferents, up to stimulus frequencies of kilohertz. We term these irregular afferents the transient system signaling dynamic otolithic stimulation. A 500-Hz vibration preferentially activates the otolith irregular afferents, since regular afferents are not activated at intensities used in clinical testing, whereas irregular afferents have low thresholds. We show how this sustained and transient distinction applies at the vestibular nuclei. The two systems have differential responses to vibration and sound, to ototoxic antibiotics, to galvanic stimulation, and to natural linear acceleration, and such differential sensitivity allows probing of the two systems. A 500-Hz vibration that selectively activates irregular otolithic afferents results in stimulus-locked eye movements in animals and humans. The preparatory myogenic potentials for these eye movements are measured in the new clinical test of otolith function-ocular vestibular-evoked myogenic potentials. We suggest 500-Hz vibration may identify the contribution of the transient system to vestibular controlled

  3. Neurotransmitters in the vestibular system.

    Science.gov (United States)

    Balaban, C D

    2016-01-01

    Neuronal networks that are linked to the peripheral vestibular system contribute to gravitoinertial sensation, balance control, eye movement control, and autonomic function. Ascending connections to the limbic system and cerebral cortex are also important for motion perception and threat recognition, and play a role in comorbid balance and anxiety disorders. The vestibular system also shows remarkable plasticity, termed vestibular compensation. Activity in these networks is regulated by an interaction between: (1) intrinsic neurotransmitters of the inner ear, vestibular nerve, and vestibular nuclei; (2) neurotransmitters associated with thalamocortical and limbic pathways that receive projections originating in the vestibular nuclei; and (3) locus coeruleus and raphe (serotonergic and nonserotonergic) projections that influence the latter components. Because the ascending vestibular interoceptive and thalamocortical pathways include networks that influence a broad range of stress responses (endocrine and autonomic), memory consolidation, and cognitive functions, common transmitter substrates provide a basis for understanding features of acute and chronic vestibular disorders. © 2016 Elsevier B.V. All rights reserved.

  4. [BEHAVIOURAL AND FUNCTIONAL VESTIBULAR DISTURBANCES AFTER SPACE FLIGHT. 1. MAMMALS].

    Science.gov (United States)

    Lychakov, D V

    2015-01-01

    The review contains data on functional changes in mammals caused by changes in the operation of vestibular system after space flight. These data show that the vestibular system of mammals responds to weightlessness challenge differently at various ontogenetic stages. Orbital space flight conditions have a weak effect on the developing vestibular system during embryonic period. The weightlessness conditions have rather beneficial effect on development of the fetuses. During the early postnatal period, when optimal sensory-motor tactics are created, the prolonged stay under conditions of space flight leads to development of novel, "extraterrestrial" sensory-motor programs that can be fixed in CNS, apparently, for the whole life. In adult individuals after landing essential vestibular changes and disturbances may occur that depend on the spaceflight duration. The adult organism must simultaneously solve two contradicting problems--it should adapt to weightlessness conditions, and should not adapt to them to pass the process of readaptation after returning easier. Thus, individuals must protect themselves against weightlessness influence to keep the intact initial state of health. The protection methods against weightlessness ought to be adjusted according to the duration of space flight. It should be mentioned that not all functional changes registered in adult individuals after landing can be adequately explained. Some of these changes may have chronic or even pathological character. The question of necessity to examine the influence of weightlessness on an aging (senile) organism and on its vestibular system is raised for the first time in this review. In our opinion the development of space gerontology, as a special branch of space biology and medicine, is of undoubted interest, and in the future it may be of practical importance especially taking into account the steadily growing age of cosmonauts (astronauts).

  5. Enhancing vestibular function in the elderly with imperceptible electrical stimulation.

    Science.gov (United States)

    Serrador, Jorge M; Deegan, Brian M; Geraghty, Maria C; Wood, Scott J

    2018-01-10

    Age-related loss of vestibular function can result in decrements in gaze stabilization and increased fall risk in the elderly. This study was designed to see if low levels of electrical stochastic noise applied transcutaneously to the vestibular system can improve a gaze stabilization reflex in young and elderly subject groups. Ocular counter-rolling (OCR) using a video-based technique was obtained in 16 subjects during low frequency passive roll tilts. Consistent with previous studies, there was a significant reduction in OCR gains in the elderly compared to the young group. Imperceptible stochastic noise significantly increased OCR in the elderly (Mean 23%, CI: 17-35%). Increases in OCR gain were greatest for those with lowest baseline gain and were negligible in those with normal gain. Since stimulation was effective at low levels undetectable to subjects, stochastic noise may provide a new treatment alternative to enhance vestibular function, specifically otolith-ocular reflexes, in the elderly or patient populations with reduced otolith-ocular function.

  6. BASIC CONCEPTS IN UNDERSTANDING RECOVERY OF FUNCTION IN VESTIBULAR REFLEX NETWORKS DURING VESTIBULAR COMPENSATION

    Directory of Open Access Journals (Sweden)

    Kenna ePeusner

    2012-02-01

    Full Text Available Unilateral peripheral vestibular lesions produce a syndrome of oculomotor and postural deficits with the symptoms at rest, the static symptoms, partially or completely normalizing shortly after the lesion due to a process known as vestibular compensation. The symptoms are thought to result from changes in the activity of vestibular sensorimotor reflexes. Since the vestibular nuclei must be intact for recovery to occur, many investigations have focused on studying these neurons after lesions. At present, the neuronal plasticity underlying early recovery from the static symptoms is not fully understood. Here we propose that knowledge of the reflex identity and input-output connections of the recorded neurons is essential to link the responses to animal behavior. We further propose that the cellular mechanisms underlying vestibular compensation can be sorted out by characterizing the synaptic responses and time course for change in morphologically-defined subsets of vestibular reflex projection neurons. Accordingly, this review focuses on the perspective gained by performing electrophysiological and immunolabeling studies on a specific subset of morphologically-defined, glutamatergic vestibular reflex projection neurons, the principal cells of the chick tangential nucleus. Reference is made to pertinent findings from other studies on vestibular nuclei neurons, but no comprehensive review of the literature is intended since broad reviews already exist. From recording excitatory and inhibitory spontaneous synaptic activity in principal cells, we find that the rebalancing of excitatory synaptic drive bilaterally is essential for vestibular compensation to proceed. This work is important for it defines for the first time the excitatory and inhibitory nature of the changing synaptic inputs and the time course for changes in a morphologically-defined subset of vestibular reflex projection neurons during early stages of vestibular compensation.

  7. The Vestibular Implant Input Interacts with Residual Natural Function

    Directory of Open Access Journals (Sweden)

    Raymond van de Berg

    2017-12-01

    Full Text Available ObjectivePatients with bilateral vestibulopathy (BV can still have residual “natural” function. This might interact with “artificial” vestibular implant input (VI-input. When fluctuating, it could lead to vertigo attacks. Main objective was to investigate how “artificial” VI-input is integrated with residual “natural” input by the central vestibular system. This, to explore (1 whether misalignment in the response of “artificial” VI-input is sufficiently counteracted by well-aligned residual “natural” input and (2 whether “artificial” VI-input is able to influence and counteract the response to residual “natural” input, to show feasibility of a “vestibular pacemaker.”Materials and methodsFive vestibular electrodes in four BV patients implanted with a VI were available. This involved electrodes with a predominantly horizontal response and electrodes with a predominantly vertical response. Responses to predominantly horizontal residual “natural” input and predominantly horizontal and vertical “artificial” VI-input were separately measured first. Then, inputs were combined in conditions where both would hypothetically collaborate or counteract. In each condition, subjects were subjected to 60 cycles of sinusoidal stimulation presented at 1 Hz. Gain, asymmetry, phase and angle of eye responses were calculated. Signal averaging was performed.ResultsCombining residual “natural” input and “artificial” VI-input resulted in an interaction in which characteristics of the resulting eye movement responses could significantly differ from those observed when responses were measured for each input separately (p < 0.0013. In the total eye response, inputs with a stronger vector magnitude seemed to have stronger weights than inputs with a lower vector magnitude, in a non-linear combination. Misalignment in the response of “artificial” VI-input was not sufficiently counteracted by well-aligned residual

  8. The Vestibular Implant Input Interacts with Residual Natural Function.

    Science.gov (United States)

    van de Berg, Raymond; Guinand, Nils; Ranieri, Maurizio; Cavuscens, Samuel; Khoa Nguyen, T A; Guyot, Jean-Philippe; Lucieer, Florence; Starkov, Dmitrii; Kingma, Herman; van Hoof, Marc; Perez-Fornos, Angelica

    2017-01-01

    Patients with bilateral vestibulopathy (BV) can still have residual "natural" function. This might interact with "artificial" vestibular implant input (VI-input). When fluctuating, it could lead to vertigo attacks. Main objective was to investigate how "artificial" VI-input is integrated with residual "natural" input by the central vestibular system. This, to explore (1) whether misalignment in the response of "artificial" VI-input is sufficiently counteracted by well-aligned residual "natural" input and (2) whether "artificial" VI-input is able to influence and counteract the response to residual "natural" input, to show feasibility of a "vestibular pacemaker." Five vestibular electrodes in four BV patients implanted with a VI were available. This involved electrodes with a predominantly horizontal response and electrodes with a predominantly vertical response. Responses to predominantly horizontal residual "natural" input and predominantly horizontal and vertical "artificial" VI-input were separately measured first. Then, inputs were combined in conditions where both would hypothetically collaborate or counteract. In each condition, subjects were subjected to 60 cycles of sinusoidal stimulation presented at 1 Hz. Gain, asymmetry, phase and angle of eye responses were calculated. Signal averaging was performed. Combining residual "natural" input and "artificial" VI-input resulted in an interaction in which characteristics of the resulting eye movement responses could significantly differ from those observed when responses were measured for each input separately (p < 0.0013). In the total eye response, inputs with a stronger vector magnitude seemed to have stronger weights than inputs with a lower vector magnitude, in a non-linear combination. Misalignment in the response of "artificial" VI-input was not sufficiently counteracted by well-aligned residual "natural" input. "Artificial" VI-input was able to significantly influence and counteract the response to

  9. Rescue of peripheral vestibular function in Usher syndrome mice using a splice-switching antisense oligonucleotide.

    Science.gov (United States)

    Vijayakumar, Sarath; Depreux, Frederic F; Jodelka, Francine M; Lentz, Jennifer J; Rigo, Frank; Jones, Timothy A; Hastings, Michelle L

    2017-09-15

    Usher syndrome type 1C (USH1C/harmonin) is associated with profound retinal, auditory and vestibular dysfunction. We have previously reported on an antisense oligonucleotide (ASO-29) that dramatically improves auditory function and balance behavior in mice homozygous for the harmonin mutation Ush1c c.216G > A following a single systemic administration. The findings were suggestive of improved vestibular function; however, no direct vestibular assessment was made. Here, we measured vestibular sensory evoked potentials (VsEPs) to directly assess vestibular function in Usher mice. We report that VsEPs are absent or abnormal in Usher mice, indicating profound loss of vestibular function. Strikingly, Usher mice receiving ASO-29 treatment have normal or elevated vestibular response thresholds when treated during a critical period between postnatal day 1 and 5, respectively. In contrast, treatment of mice with ASO-29 treatment at P15 was minimally effective at rescuing vestibular function. Interestingly, ASO-29 treatment at P1, P5 or P15 resulted in sufficient vestibular recovery to support normal balance behaviors, suggesting a therapeutic benefit to balance with ASO-29 treatment at P15 despite the profound vestibular functional deficits that persist with treatment at this later time. These findings provide the first direct evidence of an effective treatment of peripheral vestibular function in a mouse model of USH1C and reveal the potential for using antisense technology to treat vestibular dysfunction. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. From ear to uncertainty: Vestibular contributions to cognitive function.

    OpenAIRE

    Paul eSmith; Yiwen eZheng

    2013-01-01

    In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and neocortex play in spatial orientation. In this review we summarize the evidence that vestibular loss causes cognitive disorders, espe...

  11. Determination of the functional status of vestibular apparatus at children aged 5-6 years old.

    Directory of Open Access Journals (Sweden)

    Moiseenko E.K.

    2012-02-01

    Full Text Available The physiological methods of determination of the functional state of vestibular analyzer are considered. The indexes of systole and diastole pressure, frequencies of heart-throbs, are chosen. Methods were used before and after standard vestibular irritation. Research was conducted on the base of child's preschool establishment. In it took part 120 children in age 5 - 6 years. Insufficient development of vestibular analyzer is set for children. Selected exercise for the improvement of spatial orientation and statodynamic stability.

  12. Vergence and Standing Balance in Subjects with Idiopathic Bilateral Loss of Vestibular Function.

    Science.gov (United States)

    Kapoula, Zoï; Gaertner, Chrystal; Yang, Qing; Denise, Pierre; Toupet, Michel

    2013-01-01

    There is a natural symbiosis between vergence and vestibular responses. Deficits in vergence can lead to vertigo, disequilibrium, and postural instability. This study examines both vergence eye movements in patients with idiopathic bilateral vestibular loss, and their standing balance in relation to vergence. Eleven patients participated in the study and 16 controls. Bilateral loss of vestibular function was objectified with many tests; only patients without significant response to caloric tests, to video head impulse tests and without vestibular evoked myogenic potentials were included in the study. A LED display with targets at 20, 40, and 100 cm along the median plane was used to elicit vergence eye movements, recorded with the IRIS device. Four conditions were run, each lasting 1 min: fixation of a LED at 40 cm (convergence of 9°), at 150 cm (convergence of 2.3°); this last condition was repeated with eyes closed. Comparison of the eyes closed-eyes open conditions at 150 cm allowed evaluation of the Romberg Quotient. In the forth condition, two LEDS, at 20 and at 100 cm, were light on, one after the other for 1 sec, causing the eyes to converge then diverge. Standing balance was recorded with an accelerometer placed at the back near the center of mass (McRoberts, Dynaport). Relative to controls, convergence eye movements in patients showed significantly lower accuracy, lower mean velocity, and saccade intrusions of significantly higher amplitude. The normalized 90% area of body sway was significantly higher for patients than for controls for all conditions. Yet, similarly to controls, postural stability was better while fixating at near (sustained convergence) than at far, or while making active vergence movements. We argue that vestibular loss deteriorates convergence, but even deficient, convergence can be helpful for postural control.

  13. Vergence and Standing Balance in Subjects with Idiopathic Bilateral Loss of Vestibular Function.

    Directory of Open Access Journals (Sweden)

    Zoï Kapoula

    Full Text Available There is a natural symbiosis between vergence and vestibular responses. Deficits in vergence can lead to vertigo, disequilibrium, and postural instability. This study examines both vergence eye movements in patients with idiopathic bilateral vestibular loss, and their standing balance in relation to vergence. Eleven patients participated in the study and 16 controls. Bilateral loss of vestibular function was objectified with many tests; only patients without significant response to caloric tests, to video head impulse tests and without vestibular evoked myogenic potentials were included in the study.A LED display with targets at 20, 40, and 100 cm along the median plane was used to elicit vergence eye movements, recorded with the IRIS device.Four conditions were run, each lasting 1 min: fixation of a LED at 40 cm (convergence of 9°, at 150 cm (convergence of 2.3°; this last condition was repeated with eyes closed. Comparison of the eyes closed-eyes open conditions at 150 cm allowed evaluation of the Romberg Quotient. In the forth condition, two LEDS, at 20 and at 100 cm, were light on, one after the other for 1 sec, causing the eyes to converge then diverge. Standing balance was recorded with an accelerometer placed at the back near the center of mass (McRoberts, Dynaport.Relative to controls, convergence eye movements in patients showed significantly lower accuracy, lower mean velocity, and saccade intrusions of significantly higher amplitude.The normalized 90% area of body sway was significantly higher for patients than for controls for all conditions. Yet, similarly to controls, postural stability was better while fixating at near (sustained convergence than at far, or while making active vergence movements. We argue that vestibular loss deteriorates convergence, but even deficient, convergence can be helpful for postural control.

  14. Stereotactic radiotherapy of vestibular schwannoma. Hearing preservation, vestibular function, and local control following primary and salvage radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Putz, Florian; Mueller, Jan; Wimmer, Caterina; Goerig, Nicole; Knippen, Stefan; Semrau, Sabine; Fietkau, Rainer; Lettmaier, Sebastian [Friedrich-Alexander-University Erlangen-Nuremberg, Department of Radiation Oncology, Erlangen (Germany); Iro, Heinrich; Grundtner, Philipp [Friedrich-Alexander-University Erlangen-Nuremberg, Department of Otorhinolaryngology - Head and Neck Surgery, Erlangen (Germany); Eyuepoglu, Ilker; Roessler, Karl [Friedrich-Alexander-University Erlangen-Nuremberg, Department of Neurosurgery, Erlangen (Germany)

    2017-03-15

    The aim of this publication is to present long-term data on functional outcomes and tumor control in a cohort of 107 patients treated with stereotactic radiotherapy (RT) for vestibular schwannoma. Included were 107 patients with vestibular schwannoma (primary or recurrent following resection) treated with stereotactic RT (either fractioned or single-dose radiosurgery) between October 2002 and December 2013. Local control and functional outcomes were determined. Analysis of hearing preservation was limited to a subgroup of patients with complete audiometric data collected before treatment and during follow-up. Vestibular function test (FVT) results could be analyzed in a subset of patients and were compared to patient-reported dizziness. After a mean follow-up of 46.3 months, actuarial local control for the whole cohort was 100% after 2, 97.6% after 5, and 94.1% after 10 years. In patients with primary RT, serviceable hearing was preserved in 72%. Predictors for preservation of serviceable hearing in multivariate analysis were time of follow-up (odds ratio, OR = 0.93 per month; p = 0.021) and pre-RT tumor size (Koos stage I-IIa vs. IIb-IV; OR = 0.15; p = 0.031). Worsening of FVT results was recorded in 17.6% (N = 3). Profound discrepancy of patient-reported dizziness and FVT results was observed after RT. In patients with primary RT, worsening of facial nerve function occurred in 1.7% (N = 1). Stereotactic RT of vestibular schwannoma provides good functional outcomes and high control rates. Dependence of hearing preservation on time of follow-up and initial tumor stage has to be considered. (orig.) [German] Praesentation von Langzeitdaten zu funktionellen Ergebnissen und Tumorkontrolle nach stereotaktischer Radiotherapie (RT) in einer Kohorte von 107 Patienten mit Akustikusneurinom. Zwischen Oktober 2002 und Dezember 2013 wurden 107 Patienten mit Akustikusneurinom (primaer oder rezidiviert nach vorangegangener Resektion) mittels stereotaktischer RT behandelt

  15. Vestibular autonomic regulation (including motion sickness and the mechanism of vomiting)

    Science.gov (United States)

    Balaban, C. D.

    1999-01-01

    Autonomic manifestations of vestibular dysfunction and motion sickness are well established in the clinical literature. Recent studies of 'vestibular autonomic regulation' have focused predominantly on autonomic responses to stimulation of the vestibular sense organs in the inner ear. These studies have shown that autonomic responses to vestibular stimulation are regionally selective and have defined a 'vestibulosympathetic reflex' in animal experiments. Outside the realm of experimental preparations, however, the importance of vestibular inputs in autonomic regulation is unclear because controls for secondary factors, such as affective/emotional responses and cardiovascular responses elicited by muscle contraction and regional blood pooling, have been inadequate. Anatomic and physiologic evidence of an extensive convergence of vestibular and autonomic information in the brainstem suggests though that there may be an integrated representation of gravitoinertial acceleration from vestibular, somatic, and visceral receptors for somatic and visceral motor control. In the case of vestibular dysfunction or motion sickness, the unpleasant visceral manifestations (e.g. epigastric discomfort, nausea or vomiting) may contribute to conditioned situational avoidance and the development of agoraphobia.

  16. Development and Function of the Mouse Vestibular System in the Absence of Gravity Perception

    Science.gov (United States)

    Wolgemuth, Debra J.

    2005-01-01

    The hypothesis that was tested in this research was that the absence of gravity perception, such as would occur in space, would affect the development and function of the vestibular and central nervous systems. Further, we postulated that these effects would be more significant at specific stages of post-natal development of the animal. We also proposed the use of molecular genetic approaches that would provide important information as to the hierarchy of gene function during the development and subsequent function of the vestibular system. The tilted (tlt) mutant mouse has been characterized as lacking the ability to provide sensory input to the gravity receptors. The tlt/tlt mutant mice were a particularly attractive model for the study of vestibular function since the primary defect was limited to the receptor part of the vestibular system, and there were no detectable abnormal phenotypes in other organ systems. The goal of the proposed studies was to assess immediate and delayed effects of the lack of gravity perception on the vestibular system. Particular attention was paid to characterizing primarily affected periods of vestibular morphogenesis, and to identifying downstream genetic pathways that are altered in the CNS of the tlt/tlt mutant mouse. The specific aims were: (1) to characterize the postnatal morphogenesis of the CNS in the tlt mutant mouse, using detailed morphometric analysis of isolated vestibular ganglia and brain tissue at different stages of postnatal development and assessment of apoptotic cell death; (2) to examine the expression of selected genes implicated by mutational analysis to be important in vestibular development or function by in situ hybridization or immunohistochemistry in the mutant mice; and (3) to identify other genes involved in vestibular development and function, using differential cloning strategies to isolate genes whose expression is changed in the mutant versus normal vestibular system.

  17. What can posturography tell us about vestibular function?

    Science.gov (United States)

    Black, F. O.

    2001-01-01

    Patients with balance disorders want answers to the following basic questions: (1) What is causing my problem? and (2) What can be done about my problem? Information to fully answer these questions must include status of both sensory and motor components of the balance control systems. Computerized dynamic posturography (CDP) provides quantitative assessment of both sensory and motor components of postural control along with how the sensory inputs to the brain interact. This paper reviews the scientific basis and clinical applications of CDP. Specifically, studies describing the integration of vestibular inputs with other sensory systems for postural control are briefly summarized. Clinical applications, including assessment, rehabilitation, and management are presented. Effects of aging on postural control along with prevention and management strategies are discussed.

  18. Input–Output Functions of Vestibular Afferent Responses to Air-Conducted Clicks in Rats

    National Research Council Canada - National Science Library

    Zhu, Hong; Tang, Xuehui; Wei, Wei; Maklad, Adel; Mustain, William; Rabbitt, Richard; Highstein, Steve; Allison, Jerome; Zhou, Wu

    2014-01-01

    ...) have proven useful in clinical assessment of vestibular function. VEMPs are commonly interpreted as a test of saccular function, based on neurophysiological evidence showing activation of saccular afferents by intense acoustic click stimuli...

  19. Electrophysiological Measurements of Peripheral Vestibular Function-A Review of Electrovestibulography.

    Science.gov (United States)

    Brown, Daniel J; Pastras, Christopher J; Curthoys, Ian S

    2017-01-01

    Electrocochleography (EcochG), incorporating the Cochlear Microphonic (CM), the Summating Potential (SP), and the cochlear Compound Action Potential (CAP), has been used to study cochlear function in humans and experimental animals since the 1930s, providing a simple objective tool to assess both hair cell (HC) and nerve sensitivity. The vestibular equivalent of ECochG, termed here Electrovestibulography (EVestG), incorporates responses of the vestibular HCs and nerve. Few research groups have utilized EVestG to study vestibular function. Arguably, this is because stimulating the cochlea in isolation with sound is a trivial matter, whereas stimulating the vestibular system in isolation requires significantly more technical effort. That is, the vestibular system is sensitive to both high-level sound and bone-conducted vibrations, but so is the cochlea, and gross electrical responses of the inner ear to such stimuli can be difficult to interpret. Fortunately, several simple techniques can be employed to isolate vestibular electrical responses. Here, we review the literature underpinning gross vestibular nerve and HC responses, and we discuss the nomenclature used in this field. We also discuss techniques for recording EVestG in experimental animals and humans and highlight how EVestG is furthering our understanding of the vestibular system.

  20. Gene expression, signal transduction pathways and functional networks associated with growth of sporadic vestibular schwannomas

    DEFF Research Database (Denmark)

    Sass, Hjalte C.R.; Borup, Rehannah; Alanin, Mikkel

    2017-01-01

    The objective of this study was to determine global gene expression in relation to Vestibular schwannomas (VS) growth rate and to identify signal transduction pathways and functional molecular networks associated with growth. Repeated magnetic resonance imaging (MRI) prior to surgery determined...... and analyzed by dChip software. Differential gene expression was defined as a 1.5-fold difference between fast and slow growing tumors (>... of signal transduction pathways and functional molecular networks associated with tumor growth. In total 109 genes were deregulated in relation to tumor growth rate. Genes associated with apoptosis, growth and cell proliferation were deregulated. Gene ontology included regulation of the cell cycle, cell...

  1. Ocular Motor Function in Patients with Bilateral Vestibular Weakness

    Directory of Open Access Journals (Sweden)

    Seyyed Amir Hossein Ghazizadeh Hashemi

    2016-05-01

    Full Text Available Introduction: Patients with bilateral weakness (BW have many difficulties in gaze stability that interfere with their normal function. The aim of this study was to evaluate ocular motor functions in patients with BW to better understand the problem of gaze instability in these patients.   Materials and Methods: Patients were referred from the Otolaryngology Department for Vestibular Assessment to our clinic between November 2014 and March 2015. We assessed ocular motor function (gaze, saccade, and smooth pursuit in patients over the age of 18 years with BW, as verified by a caloric test.   Results: Seventy-eight patients completed all the tests. The mean age of patients was 51.9 (±15.9 years, and 47 (60% were female. Abnormal results were found in five (6.4%, 32 (41%, and seven (9% patients with respect to gaze, smooth pursuit, and saccade, respectively. There were positive but relatively weak relationships between age and ocular motor results.   Conclusion:  Patients with BW suffer from dizziness and unsteadiness. These patients have abnormal function in ocular motor (especially smooth pursuit tests. The ocular motor dysfunction is responsible for gaze instability in static positions such as standing.

  2. Is Vestibular Neuritis an Immune Related Vestibular Neuropathy Inducing Vertigo?

    Directory of Open Access Journals (Sweden)

    A. Greco

    2014-01-01

    Full Text Available Objectives. To review the current knowledge of the aetiology of vestibular neuritis including viral infections, vascular occlusion, and immunomediated mechanisms and to discuss the pathogenesis with relevance to pharmacotherapy. Systematic Review Methodology. Relevant publications on the aetiology and treatment of vestibular neuritis from 1909 to 2013 were analysed. Results and Conclusions. Vestibular neuritis is the second most common cause of peripheral vestibular vertigo and is due to a sudden unilateral loss of vestibular function. Vestibular neuronitis is a disorder thought to represent the vestibular-nerve equivalent of sudden sensorineural hearing loss. Histopathological studies of patients who died from unrelated clinical problems have demonstrated degeneration of the superior vestibular nerve. The characteristic signs and symptoms include sudden and prolonged vertigo, the absence of auditory symptoms, and the absence of other neurological symptoms. The aetiology and pathogenesis of the condition remain unknown. Proposed theories of causation include viral infections, vascular occlusion, and immunomediated mechanisms. The management of vestibular neuritis involves symptomatic treatment with antivertiginous drugs, causal treatment with corticosteroids, and physical therapy. Antiviral agents did not improve the outcomes.

  3. Functional testing of the vestibular ocular reflex (VOR

    Directory of Open Access Journals (Sweden)

    Stefano eRamat

    2012-03-01

    Full Text Available The experimental assessment of the vestibulo-ocular-reflex (VOR gain provides an objective and quantitative measure of VOR performance which is nonetheless difficult to correlate with its efficiency in everyday living conditions. We developed the Head Impulse Testing Device (HITD based on an inertial sensing system allowing to investigate the functional performance of the VOR by testing its gaze stabilization ability in response to head impulses at different head angular accelerations. HITD results on a population of 39 vestibular patients were compared to those of 22 controls. Overall the sensitivity of the HITD was 92% against the results of the clinical head impulse test and 83% against the clinical diagnosis, while the specificity was 58% against the clinical head impulse test and 83% against the diagnosis. The HITD appears to be a very promising tool for detecting abnormal VOR performance while providing information on the functional performance of the rotational VOR. As compared to the usual testing devices the HITD tests higher frequencies and accelerations that characterize head movements in everyday life activities and provides a functional assessment that is more likely to be related to the subject’s self-feeling.

  4. Prevalence of abnormalities in vestibular function and balance among HIV-seropositive and HIV-seronegative women and men.

    Directory of Open Access Journals (Sweden)

    Helen S Cohen

    Full Text Available BACKGROUND: Most HIV-seropositive subjects in western countries receive highly active antiretroviral therapy (HAART. Although many aspects of their health have been studied, little is known about their vestibular and balance function. The goals of this study were to determine the prevalences of vestibular and balance impairments among HIV-seropositive and comparable seronegative men and women and to determine if those groups differed. METHODS: Standard screening tests of vestibular and balance function, including head thrusts, Dix-Hallpike maneuvers, and Romberg balance tests on compliant foam were performed during semiannual study visits of participants who were enrolled in the Baltimore and Washington, D. C. sites of the Multicenter AIDS Cohort Study and the Women's Interagency HIV Study. RESULTS: No significant differences by HIV status were found on most tests, but HIV-seropositive subjects who were using HAART had a lower frequency of abnormal Dix-Hallpike nystagmus than HIV-seronegative subjects. A significant number of nonclassical Dix-Hallpike responses were found. Age was associated with Romberg scores on foam with eyes closed. Sex was not associated with any of the test scores. CONCLUSION: These findings suggest that HAART-treated HIV infection has no harmful association with vestibular function in community-dwelling, ambulatory men and women. The association with age was expected, but the lack of association with sex was unexpected. The presence of nonclassical Dix-Hallpike responses might be consistent with central nervous system lesions.

  5. Electrophysiological Measurements of Peripheral Vestibular Function?A Review of Electrovestibulography

    OpenAIRE

    Brown, Daniel J.; Christopher J. Pastras; Curthoys, Ian S.

    2017-01-01

    Electrocochleography (EcochG), incorporating the Cochlear Microphonic (CM), the Summating Potential (SP), and the cochlear Compound Action Potential (CAP), has been used to study cochlear function in humans and experimental animals since the 1930s, providing a simple objective tool to assess both hair cell (HC) and nerve sensitivity. The vestibular equivalent of ECochG, termed here Electrovestibulography (EVestG), incorporates responses of the vestibular HCs and nerve. Few research groups hav...

  6. An electronic prosthesis mimicking the dynamic vestibular function

    Science.gov (United States)

    Shkel, Andrei M.

    2006-03-01

    This paper reports our progress toward development of a unilateral vestibular prosthesis. The sensing element of the prosthesis is a custom designed one-axis MEMS gyroscope. Similarly to the natural semicircular canal, the microscopic gyroscope senses angular motion of the head and generates voltages proportional to the corresponding angular accelerations. Then, voltages are sent to the pulse generating unit where angular motion is translated into voltage pulses. The voltage pulses are converted into current pulses and are delivered through specially designed electrodes, conditioned to stimulate the corresponding vestibular nerve branch. Our preliminary experimental evaluations of the prosthesis on a rate table indicate that the device's output matches the average firing rate of vestibular neurons to those in animal models reported in the literature. The proposed design is scalable; the sensing unit, pulse generator, and the current source can be potentially implemented on a single chip using integrated MEMS technology.

  7. The development of vestibular system and related function in mammals: Impact of gravity

    Directory of Open Access Journals (Sweden)

    Marc eJamon

    2014-02-01

    Full Text Available This chapter reviews the knowledge about the adaptation to Earth gravity during the development of mammals. The impact of early exposure to altered gravity is evaluated at the level of the functions related to the vestibular system, including postural control, homeostatic regulation, and spatial memory. The hypothesis of critical periods in the adaptation to gravity is discussed. Demonstrating a critical period requires removing the gravity stimulus during delimited time windows, what is impossible to do on Earth surface. The Surgical destruction of the vestibular apparatus, and the use of mice strains with defective graviceptors have provided useful information on the consequences of missing gravity perception, and the possible compensatory mechanisms, but transitory suppression of the stimulus can only be operated during spatial flight. The rare studies on rat pups housed on board of space shuttle significantly contributed to this problem, but the use of hypergravity environment, produced by means of chronic centrifugation, is the only available tool when repeated experiments must be carried out on Earth. Even though hypergravity is sometimes considered as a mirror situation to microgravity, the two situations cannot be confused because a gravitational force is still present. The theoretical considerations that validate the paradigm of hypergravity to evaluate critical periods are discussed. The question of adaption of graviceptor is questioned from an evolutionary point of view. It is possible that graviception is hardwired, because life on Earth has evolved under the constant pressure of gravity. The rapid acquisition of motor programming by precocial mammals in minutes after birth is consistent with this hypothesis, but the slow development of motor skills in altricial species and the plasticity of vestibular perception in adults suggest that gravity experience is required for the tuning of graviceptors. The possible reasons for this

  8. The development of vestibular system and related functions in mammals: impact of gravity.

    Science.gov (United States)

    Jamon, Marc

    2014-01-01

    This chapter reviews the knowledge about the adaptation to Earth gravity during the development of mammals. The impact of early exposure to altered gravity is evaluated at the level of the functions related to the vestibular system, including postural control, homeostatic regulation, and spatial memory. The hypothesis of critical periods in the adaptation to gravity is discussed. Demonstrating a critical period requires removing the gravity stimulus during delimited time windows, what is impossible to do on Earth surface. The surgical destruction of the vestibular apparatus, and the use of mice strains with defective graviceptors have provided useful information on the consequences of missing gravity perception, and the possible compensatory mechanisms, but transitory suppression of the stimulus can only be operated during spatial flight. The rare studies on rat pups housed on board of space shuttle significantly contributed to this problem, but the use of hypergravity environment, produced by means of chronic centrifugation, is the only available tool when repeated experiments must be carried out on Earth. Even though hypergravity is sometimes considered as a mirror situation to microgravity, the two situations cannot be confused because a gravitational force is still present. The theoretical considerations that validate the paradigm of hypergravity to evaluate critical periods are discussed. The question of adaption of graviceptor is questioned from an evolutionary point of view. It is possible that graviception is hardwired, because life on Earth has evolved under the constant pressure of gravity. The rapid acquisition of motor programming by precocial mammals in minutes after birth is consistent with this hypothesis, but the slow development of motor skills in altricial species and the plasticity of vestibular perception in adults suggest that gravity experience is required for the tuning of graviceptors. The possible reasons for this dichotomy are discussed.

  9. Functional Plasticity after Unilateral Vestibular Midbrain Infarction in Human Positron Emission Tomography.

    Science.gov (United States)

    Becker-Bense, Sandra; Buchholz, Hans-Georg; Baier, Bernhard; Schreckenberger, Mathias; Bartenstein, Peter; Zwergal, Andreas; Brandt, Thomas; Dieterich, Marianne

    2016-01-01

    The aim of the study was to uncover mechanisms of central compensation of vestibular function at brainstem, cerebellar, and cortical levels in patients with acute unilateral midbrain infarctions presenting with an acute vestibular tone imbalance. Eight out of 17 patients with unilateral midbrain infarctions were selected on the basis of signs of a vestibular tone imbalance, e.g., graviceptive (tilts of perceived verticality) and oculomotor dysfunction (skew deviation, ocular torsion) in F18-fluordeoxyglucose (FDG)-PET at two time points: A) in the acute stage, and B) after recovery 6 months later. Lesion-behavior mapping analyses with MRI verified the exact structural lesion sites. Group subtraction analyses and comparisons with healthy controls were performed with Statistic Parametric Mapping for the PET data. A comparison of PET A of acute-stage patients with that of healthy controls showed increases in glucose metabolism in the cerebellum, motion-sensitive visual cortex areas, and inferior temporal lobe, but none in vestibular cortex areas. At the supratentorial level bilateral signal decreases dominated in the thalamus, frontal eye fields, and anterior cingulum. These decreases persisted after clinical recovery in contrast to the increases. The transient activations can be attributed to ocular motor and postural recovery (cerebellum) and sensory substitution of vestibular function for motion perception (visual cortex). The persisting deactivation in the thalamic nuclei and frontal eye fields allows alternative functional interpretations of the thalamic nuclei: either a disconnection of ascending sensory input occurs or there is a functional mismatch between expected and actual vestibular activity. Our data support the view that both thalami operate separately for each hemisphere but receive vestibular input from ipsilateral and contralateral midbrain integration centers. Normally they have gatekeeper functions for multisensory input to the cortex and automatic

  10. Effects of nitric oxide on the vestibular functional recovery after unilateral labyrinthectomy.

    Science.gov (United States)

    Park, J S; Jeong, H S

    2000-12-01

    The effects of nitric oxide on the vestibular function recovery following unilateral labyrinthectomy were studied. Male Sprague-Dawley rats treated with N-omega-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, were subjected to destruction of the unilateral vestibular apparatus and spontaneous nystagmus was observed. To explore the role of nitric oxide on the potassium current, the whole cell patch clamp technique was applied on isolated medial vestibular nuclear neurons. The frequency of spontaneous nystagmus that appeared in L-NAME-treated rats was higher and maintained longer than in control animals. Potassium currents in the isolated medial vestibular nucleus were inhibited by nitric oxide liberating agents, sodium nitroprusside and S-nitroso-N-acetylpenicillamine. After blockade of calcium dependent potassium currents by high EGTA (11 mM)-containing pipette solution, sodium nitroprusside did not inhibit the outward potassium currents. 8-Bromoguanosine 3,5-cyclic monophosphate, a membrane-permeable cGMP analogue, produced similar effects to inhibit the outward potassium currents as sodium nitroprusside. These results suggest that nitric oxide production after unilateral labyrinthectomy would help to facilitate vestibular compensation by inhibiting calcium-dependent potassium currents through increasing intracellular cyclic GMP, thereby increasing excitability in ipsilateral vestibular nuclear neurons.

  11. [The estimation of the efficacy of manual therapy included in the combined treatment of cochlear-vestibular disorders based on the results of computed stabilography].

    Science.gov (United States)

    Shempeleva, A É; Lopatin, A S; Morozova, S V; Gridin, L A

    2012-01-01

    The objective of the present study was to estimate the efficacy of the combined treatment of spondylogenic cochlear-vestibular disorders with the use of both medicamental and non-medicamental modalities. Computed static stabilometry was applied for diagnostics of postural disbalance and evaluation of the treatment outcomes. It was shown that the application of manual therapy for the management of 56 patients presenting with spondylogenic cochlear-vestibular disorders resulted in the decrease of tinnitus and the improvement of vestibular and cochlear functions.

  12. Investigations of the Effects of Altered Vestibular System Function on Hindlimb Anti-Gravity Muscles

    Science.gov (United States)

    Lowery, Mary Sue

    1998-01-01

    Exposure to different gravitational environments, both the microgravity of spaceflight and the hypergravity of centrifugation, result in altered vestibulo-spinal function which can be reversed by reacclimation to earth gravity (2). Control of orientation, posture, and locomotion are functions of the vestibular system which are altered by changes in gravitational environment. Not only is the vestibular system involved with coordination and proprioception, but the gravity sensing portion of the vestibular system also plays a major role in maintaining muscle tone through projections to spinal cord motoneurons that control anti-gravity muscles. I have been involved with investigations of several aspects of the link between vestibular inputs and muscle morphology and function during my work with Dr. Nancy Daunton this summer and the previous summer. We have prepared a manuscript for submission (4) to Aviation, Space, and Environmental Medicine based on work that I performed last summer in Dr. Daunton's lab. Techniques developed for that project will be utilized in subsequent experiments begun in the summer of 1998. I have been involved with the development of a pilot project to test the effects of vestibular galvanic stimulation (VGS) on anti-gravity muscles and in another project testing the effects of the ototoxic drug streptomycin on the otolith-spinal reflex and anti-gravity muscle morphology.

  13. The Effect of Vestibular Stimulation on Motor Functions of Children With Cerebral Palsy.

    Science.gov (United States)

    Tramontano, Marco; Medici, Alessandra; Iosa, Marco; Chiariotti, Alessia; Fusillo, Giulia; Manzari, Leonardo; Morelli, Daniela

    2017-07-01

    Cerebral palsy (CP) has been defined as a nonprogressive disease of movement and posture development. Physical therapy techniques use different forms of sensory stimulation to improve neuromotor development. The aim of this study was to assess the efficacy of a vestibular stimulation training in improving motor functions in cerebral palsy. Fourteen children with CP were randomly separated into two different groups in a cross-over trial. Over a period of 10 weeks, each group performed 10 sessions of 50 min of neurodevelopmental treatment (NDT) and 10 sessions of vestibular training (VR). Children were evaluated with the Gross Motor Function Measurement-88 scale, the Goal Attainment Scale and the root mean square of head accelerations. A significant improvement in the GAS-score (p = .003) was noted after NDT+VR. Vestibular stimulation integrated with NDT proved to be an effective complementary strategy for facilitating motor functioning.

  14. Plasticity of Scarpa’s ganglion neurons as a possible basis for functional restoration within vestibular endorgans

    Directory of Open Access Journals (Sweden)

    Cécile eTravo

    2012-06-01

    Full Text Available In a previous study (Brugeaud et al., 2007, we observed spontaneous restoration of the vestibular function in young adult rodents following excitotoxic injury of the neuronal network of vestibular endorgans. The functional restoration was supported by a repair of synaptic contacts between hair cells and primary vestibular neurons. This process was observed in 2/3 of the animals studied and occurred within five days following the synapse insult. To assess whether structural plasticity is a fundamental trait of altered vestibular endorgans and to decipher the cellular mechanisms that support such a repair process, we studied the neuronal regeneration and synaptogenesis in co-cultures of vestibular epithelia and Scarpa’s ganglion from young and adult rodents. We demonstrate that under specific culture conditions, primary vestibular neurons from young mice or rats exhibit robust ability to regenerate nervous processes. When co-cultured with vestibular epithelia, primary vestibular neurons were able to establish de novo contacts with hair cells. Under the present paradigm, these contacts displayed morphological features of immature synaptic contacts. This reparative capacity remained in older mice although to a lesser extent. Identifying the basic mechanisms underlying the repair process may provide a basis for novel therapeutic strategies to restore mature and functional vestibular synaptic contacts following damage or loss.

  15. Impaired Vestibular Function After Cochlear Implantation in Children: Role of Static Posturography.

    Science.gov (United States)

    Nair, Satish; Gupta, Atul; Nilakantan, Ajith; Mittal, Ruchika; Dahiya, Ruchi; Saini, Sachin; Prasad, Rachana; Vajpayee, Deepika

    2017-06-01

    To identify vestibular dysfunction in children after cochlear implant surgery and to study the utility of static posturography in evaluating vestibular function in children. A prospective study was carried out on 25 children between 2 and 7 years of age with sensorineural hearing loss with no overt vestibular dysfunction. All children underwent static posturography using Synapsis Posturographic System (SPS) software (Version 3.0, REV C) using a static platform with foam. The centre of pressure (COP) shift was recorded as statokinesiogram on the software and the mean vestibular, visual and somesthetic scores were obtained. Cochlear implantation (CI) surgery was done with insertion of Med-El Pulsar standard cochlear implant with 12 twin electrodes. Children were evaluated again after 4 weeks of CI surgery (2 weeks after switch on) with static posturography on the same SPS software. The scores obtained were compared with pre op value and data analyzed statistically by paired t tests on SPSS 18 software. The mean age was 4.6 years with range 2-7 years. All the children in the study were able to complete the test with no difficulty and the mean time required for each child was 10.2 min. The mean pre op somesthetic score was 95.16 (SD 1.52) and post op score was 94.06 (SD 1.79). The mean pre op visual score was 86.64 (SD 2.24) and post op score was 82.55 (2.89). The mean pre op vestibular score was 84.11 (SD 2.20) and post op score was 73.66 (SD 4.25). Correlation and statistical analysis of the pre and post values of each score revealed statistically significant reduction in vestibular scores post CI. The vestibular system is at high risk of injury leading to vestibular dysfunction in children during CI. Our study found the static posturography as a simple, fast and efficient tool to screen children for vestibular dysfunction post CI. Identifying the dysfunction early can help in initiating early rehabilitation measures.

  16. The endocannabinoid system: A new player in the neurochemical control of vestibular function?

    Science.gov (United States)

    Smith, Paul F; Ashton, John C; Darlington, Cynthia L

    2006-01-01

    The results of recent clinical trials of medicinal cannabinoid drugs show that dizziness and vertigo are commonly reported adverse side-effects. Cannabinoid CB1 receptors were initially thought to be expressed in very low densities in the vestibular nucleus complex (VNC). Recent immunohistochemical studies have challenged this idea and suggested that CB1 receptors may exist in numbers similar to the granule cell layer of the cerebellum. This, together with evidence that brainstem CB1 receptors have a higher efficacy than those in many other parts of the brain and that application of cannabinoids can elicit potent electrophysiological effects in VNC neurons, suggests that CB1 receptors and their endogenous ligands may be important in central vestibular function. In this review, we consider the potential clinical significance of the endocannabinoid system for the development of vestibular disorders, the effects of recreational cannabis use and the therapeutic use of medicinal cannabinoids. Copyright 2006 S. Karger AG, Basel.

  17. A função vestibular em indivíduos usuários de implante coclear Vestibular function in cochlear implant users

    Directory of Open Access Journals (Sweden)

    Ariane Solci Bonucci

    2008-04-01

    Full Text Available A ocorrência de alteração no equilíbrio no período pós-cirúrgico ao implante coclear varia de 31 a 75%. OBJETIVO: Analisar a função vestibular no período pré e pós-operatório da cirurgia de implante coclear. MATERIAL E MÉTODO: Avaliou-se a função vestibular, por meio da vectoeletronistagmografia, de 38 pacientes, no pré e pós-cirúrgico de implante coclear. RESULTADOS: A principal queixa de desequilíbrio apresentada pelos pacientes foi a tontura, seguida pela vertigem postural e pela vertigem não-postural. Dos 38 pacientes avaliados, 13% deixaram de apresentar desequilíbrio após a cirurgia de implante coclear e apenas 5% referiram piora. Houve uma melhora na sintomatologia vestibular em 13% dos pacientes, sendo que esta possibilidade pode estar relacionada ao fenômeno de compensação vestibular e pela estimulação elétrica. Entretanto, foi observada na prova calórica uma piora na funcionalidade do sistema vestibular, tanto na orelha implantada como na orelha não-implantada. Assim, não há tendência de maior comprometimento na orelha implantada. CONCLUSÃO: O estudo demonstrou que o implante coclear pode comprometer o sistema vestibular em ambas as orelhas. Entretanto, a sintomatologia vestibular ocorre em menor proporção, podendo haver melhora no desequilíbrio após a cirurgia do implante coclear.Balance alterations in the postoperative of cochlear implant surgeries varies from 31 to 75%. AIM: to analyze vestibular function in the pre and postoperative periods of cochlear implanted individuals. MATERIALS AND METHODS: the vestibular function was assessed, through electronystagmography, in 38 patients, in the pre and postoperative of cochlear implant procedures. RESULTS: The main complaint of unbalance reported by patients was dizziness, followed by postural vertigo and non-postural vertigo. Results: 13% of the patients did not show any balance disorder following cochlear implant surgery and just 5% showed symptoms

  18. VESTIBULAR FUNCTION IN A GROUP OF ADULTS WITH HIV/AIDS ON HAART.

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    Khoza-Shangase, Katijah

    2018-01-01

    The high prevalence of HIV/AIDS and the established otological manifestations of the disease have important implications for research into vestibular function in this population. The main aim of the current study was to investigate and monitor the vestibular status in a group of adult patients with AIDS receiving Highly Active Antiretroviral Therapy (HAART) and other therapies in a hospital outpatient clinic in Gauteng, South Africa. The study was exploratory and observational in nature, with repeated measures in the form of pre- and post-treatment survey; and a control group. The measures were taken before commencement of antiretroviral therapy (ARVs), three months after initiation of treatment and six months into therapy. A comparison of results of the control group and treatment group was done for all objectives. A total of 150 (104 in the treatment group and 46 in the control group) participants who were recruited through a nonprobability convenience sampling technique were included in the study. All participants were at stage three of HIV/AIDS according to their CD4+ T-cell counts at baseline. Data were analysed through descriptive statistics. Findings from the current study revealed occurrence of acute vertigo which spontaneously resolved in adults with AIDS on HAART over a monitoring period of six months; with this occurrence being higher in participants on HAART than in the control group. The symptoms occurred after diagnosis with HIV and mostly after HAART initiation; and participants who experienced vertigo did not report this to their attending doctor. Furthermore, there was a lack of a relationship between the increasing occurrences of hearing loss in the group to the presentation of vertigo over the six months of monitoring. Findings from the present study which revealed occurrence of possible acute vertigo that spontaneously resolves in adults with AIDS on HAART, over a monitoring period of six months, add to the existing literature on vestibular

  19. Vestibular rehabilitation for unilateral peripheral vestibular dysfunction.

    Science.gov (United States)

    Hillier, Susan L; McDonnell, Michelle

    2011-02-16

    This is an update of a Cochrane Review first published in The Cochrane Library in Issue 4, 2007.Unilateral peripheral vestibular dysfunction (UPVD) can occur as a result of disease, trauma or postoperatively. The dysfunction is characterised by complaints of dizziness, visual or gaze disturbances and balance impairment. Current management includes medication, physical manoeuvres and exercise regimes, the latter known collectively as vestibular rehabilitation (VR). To assess the effectiveness of vestibular rehabilitation in the adult, community-dwelling population of people with symptomatic unilateral peripheral vestibular dysfunction. We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ISRCTN and additional sources for published and unpublished trials. The most recent search was 1 July 2010, following a previous search in March 2007. Randomised trials of adults living in the community, diagnosed with symptomatic unilateral peripheral vestibular dysfunction. We sought comparisons of VR versus control (placebo etc.), other treatment (non-VR, e.g. pharmacological) or another form of VR. We considered the outcome measures of frequency and severity of dizziness or visual disturbance; changes in balance impairment, function or quality of life; and measure/s of physiological status with known functional correlation. Both authors independently extracted data and assessed trials for risk of bias. We included 27 trials, involving 1668 participants, in the review. Trials addressed the effectiveness of VR against control/sham interventions, medical interventions or other forms of VR. Individual and pooled data showed a statistically significant effect in favour of VR over control or no intervention. The exception to this was when movement-based VR was compared to physical manoeuvres for benign

  20. Vestibular rehabilitation outcomes in the elderly with chronic vestibular dysfunction.

    Science.gov (United States)

    Bayat, Arash; Pourbakht, Akram; Saki, Nader; Zainun, Zuraida; Nikakhlagh, Soheila; Mirmomeni, Golshan

    2012-11-01

    Chronic vestibular dysfunction is a frustrating problem in the elderly and can have a tremendous impact on their life, but only a few studies are available. Vestibular rehabilitation therapy (VRT) is an important therapeutic option for the neuro-otologist in treating patients with significant balance deficits. The purpose of this study was to assess the effect of vestibular rehabilitation on dizziness in elderly patients with chronic vestibular dysfunction. A total of 33 patients older than 60 years with chronic vestibular dysfunction were studied. Clinical and objective vestibular tests including videonystagmography (VNG) and dizziness handicap inventory (DHI) were carried out at their first visit, 2 weeks, and 8 weeks post-VRT. The VRT exercises were performed according to Cawthorne and Cooksey protocols. Oculomotor assessments were within normal limits in all patients. Nineteen patients (57.57%) showed abnormal canal paralysis on caloric testing which at follow-up sessions; CP values were decreased remarkably after VRT exercises. We found a significant improvement between pre-VRT and post-VRT total DHI scores (P < 0.001). This improvement was most prominent in functional subscore. Our study demonstrated that VRT is an effective therapeutic method for elderly patients with chronic vestibular dysfunction.

  1. Relationship among balance impairments, functional performance, and disability in people with peripheral vestibular hypofunction.

    Science.gov (United States)

    Gill-Body, K M; Beninato, M; Krebs, D E

    2000-08-01

    Physical therapy interventions are often based on assumed relationships among impairments, functional performance, and disability. The purposes of this study were (1) to describe balance impairments, functional performance, and disability in subjects with unilateral peripheral vestibular hypofunction (UVH) and bilateral peripheral vestibular hypofunction (BVH), (2) to examine the relationship among these factors, and (3) to determine whether disability can be explained by commonly used tests of balance and functional performance. Participants were 85 subjects (mean age=62.5 years, SD=16.5) with UVH (n=41) or BVH (n=44) diagnosed by vestibular function tests and clinical examination. Each subject completed the Dizziness Handicap Inventory (DHI) to obtain a measure of disability. Functional performance was measured with a modified Timed Up & Go Test (TUG). Balance impairments were measured with computerized posturography and balance tests. Descriptive statistics, correlational analyses, and stepwise regressions were performed. Subjects with BVH had poorer balance but similar TUG scores and perceived levels of disability, as compared with subjects with UVH. Weak to moderate correlations existed among balance measurements, TUG scores, and DHI scores. Balance impairments and TUG scores together explained 78% of the variance in DHI scores of the subjects with BVH, whereas balance impairments alone explained 13% of the variance in DHI scores of the subjects with UVH. Balance impairments and functional performance appear to be more closely related to disability in individuals with BVH as compared with those with UVH. Clinical tests of balance impairments and functional performance appear to be useful in explaining disability.

  2. Optimal Stimulus Amplitude for Vestibular Stochastic Stimulation to Improve Sensorimotor Function

    Science.gov (United States)

    Goel, R.; Kofman, I.; DeDios, Y. E.; Jeevarajan, J.; Stepanyan, V.; Nair, M.; Congdon, S.; Fregia, M.; Cohen, H.; Bloomberg, J. J.; hide

    2014-01-01

    Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts when they transition across different gravity environments. We are developing a method, based on stochastic resonance (SR), to enhance information transfer by applying non-zero levels of external noise on the vestibular system (vestibular stochastic resonance, VSR). Our previous work has shown the advantageous effects of VSR in a balance task of standing on an unstable surface. This technique to improve detection of vestibular signals uses a stimulus delivery system that is wearable or portable and provides imperceptibly low levels of white noise-based binaural bipolar electrical stimulation of the vestibular system. The goal of this project is to determine optimal levels of stimulation for SR applications by using a defined vestibular threshold of motion detection. A series of experiments were carried out to determine a robust paradigm to identify a vestibular threshold that can then be used to recommend optimal stimulation levels for SR training applications customized to each crewmember. Customizing stimulus intensity can maximize treatment effects. The amplitude of stimulation to be used in the VSR application has varied across studies in the literature such as 60% of nociceptive stimulus thresholds. We compared subjects' perceptual threshold with that obtained from two measures of body sway. Each test session was 463s long and consisted of several 15s sinusoidal stimuli, at different current amplitudes (0-2 mA), interspersed with 20-20.5s periods of no stimulation. Subjects sat on a chair with their eyes closed and had to report their perception of motion through a joystick. A force plate underneath the chair recorded medio-lateral shear forces and roll moments. First we determined the percent time during stimulation periods for which perception of motion (activity above a pre-defined threshold) was reported using the joystick, and body sway (two

  3. Vestibular Restoration and Adaptation in Vestibular Neuritis and Ramsay Hunt Syndrome With Vertigo.

    Science.gov (United States)

    Martin-Sanz, Eduardo; Rueda, Almudena; Esteban-Sanchez, Jonathan; Yanes, Joaquin; Rey-Martinez, Jorge; Sanz-Fernandez, Ricardo

    2017-08-01

    To evaluate vestibular restoration and the evolution of the compensatory saccades in acute severe inflammatory vestibular nerve paralysis, including vestibular neuritis and Ramsay Hunt syndrome with vertigo. Prospective. Tertiary referral center. Vestibular neuritis (n = 18) and Ramsay Hunt syndrome patients with vertigo (n = 13) were enrolled. After treatment with oral corticosteroids, patients were followed up for 6 months. Functional recovery of the facial nerve was scored according to the House-Brackman grading system. Caloric and video head impulse tests were performed in every patient at the time of enrolment. Subsequently, successive video head impulse test (vHIT) exploration was performed at the 1, 3, and 6-month follow-up. Eighteen patients with vestibular neuritis and 13 with Ramsay Hunt syndrome and associated vertigo were included. Vestibular function was significantly worse in patients with Ramsay Hunt syndrome than in those with vestibular neuritis. Similar compensatory saccades velocity and latency values were observed in both groups, in both the caloric and initial vHIT tests. Successive vHIT results showed a significantly higher vestibulo-ocular reflex gain recovery in vestibular neuritis patients than in Ramsay Hunt syndrome patients. A significantly faster reduction in the latency, velocity, and organization of the compensatory saccades was observed in neuritis than in Ramsay Hunt syndrome patients. In addition to the recovery of the vestibulo-ocular reflex, the reduction of latency, velocity and the organization of compensatory saccades play a role in vestibular compensation.

  4. Gene expression profiles of the cochlea and vestibular endorgans: localization and function of genes causing deafness.

    Science.gov (United States)

    Nishio, Shin-Ya; Hattori, Mitsuru; Moteki, Hideaki; Tsukada, Keita; Miyagawa, Maiko; Naito, Takehiko; Yoshimura, Hidekane; Iwasa, Yoh-Ichiro; Mori, Kentaro; Shima, Yutaka; Sakuma, Naoko; Usami, Shin-Ichi

    2015-05-01

    We sought to elucidate the gene expression profiles of the causative genes as well as the localization of the encoded proteins involved in hereditary hearing loss. Relevant articles (as of September 2014) were searched in PubMed databases, and the gene symbols of the genes reported to be associated with deafness were located on the Hereditary Hearing Loss Homepage using localization, expression, and distribution as keywords. Our review of the literature allowed us to systematize the gene expression profiles for genetic deafness in the inner ear, clarifying the unique functions and specific expression patterns of these genes in the cochlea and vestibular endorgans. The coordinated actions of various encoded molecules are essential for the normal development and maintenance of auditory and vestibular function. © The Author(s) 2015.

  5. Mouse Models for Pendrin-Associated Loss of Cochlear and Vestibular Function

    Directory of Open Access Journals (Sweden)

    Philine Wangemann

    2013-12-01

    Full Text Available The human gene SLC26A4 and the mouse ortholog Slc26a4 code for the protein pendrin, which is an anion exchanger expressed in apical membranes of selected epithelia. In the inner ear, pendrin is expressed in the cochlea, the vestibular labyrinth and the endolymphatic sac. Loss-of-function and hypo-functional mutations cause an enlargement of the vestibular aqueduct (EVA and sensorineural hearing loss. The relatively high prevalence of SLC26A4 mutations provides a strong imperative to develop rational interventions that delay, ameliorate or prevent pendrin-associated loss of cochlear and vestibular function. This review summarizes recent studies in mouse models that have been developed to delineate the role of pendrin in the physiology of hearing and balance and that have brought forward the concept that a temporally and spatially limited therapy may be sufficient to secure a life-time of normal hearing in children bearing mutations of SLC26A4.

  6. The S1P2 sphingosine 1-phosphate receptor is essential for auditory and vestibular function.

    Science.gov (United States)

    MacLennan, A John; Benner, Shannon J; Andringa, Anastasia; Chaves, Alicia H; Rosing, Joanna L; Vesey, Rachel; Karpman, Adam M; Cronier, Samantha A; Lee, Nancy; Erway, Larry C; Miller, Marian L

    2006-10-01

    Sphingosine 1-phosphate (S1P) is an endogenous growth factor with potent effects on many different cell types. Most of these effects are produced by activation of one or more of a family of G-protein coupled receptors. The S1P2 receptor can mediate S1P-induced proliferation, differentiation and survival in a wide variety of cells in culture. However, identifying essential in vivo functions for S1P2 has been hampered by its ubiquitous expression and the failure to detect any anatomical abnormalities in initial analyses of S1P2 knockout mice. We report here that all S1P2 knockout mice are profoundly deaf from postnatal day 22 and approximately half display a progressive loss of vestibular function with aging. Anatomically, both the auditory and vestibular systems appear to develop normally but then degrade. Morphological defects associated with hearing are first detected at 3 weeks postnatal as deformations of the organ of Corti/Nuel's space. By one year of age structures within the scala media are dramatically altered. The S1P2 knockout mice also display a loss of otoconia consistent with the vestibular impairment. The present data are the first to indicate that S1P signaling plays critical roles, in vivo, in auditory and vestibular functions. The data further establish that the S1P signaling occurs through the S1P2 receptor and makes an essential contribution to the structural maintenance of these systems, raising the possibility that properly targeted enhancement of this signaling may prove to be clinically beneficial.

  7. The vestibular evoked response to linear, alternating, acceleration pulses without acoustic masking as a parameter of vestibular function

    NARCIS (Netherlands)

    Oei, MLYM; Segenhout, JM; Wit, HP; Albers, FWJ

    In this study, short latency vestibular evoked potentials (VsEPs) were recorded in five guinea pigs in response to alternating linear acceleration pulses with and without acoustic masking. A steel bolt was implanted in the skull and coupled to a shaker. Linear acceleration pulses (n = 400) in

  8. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Science.gov (United States)

    Georgi, Justin A; Sipla, Justin S; Forster, Catherine A

    2013-01-01

    Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  9. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Directory of Open Access Journals (Sweden)

    Justin A Georgi

    Full Text Available Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  10. Eye movements in vestibular disorders.

    Science.gov (United States)

    Kheradmand, A; Colpak, A I; Zee, D S

    2016-01-01

    The differential diagnosis of patients with vestibular symptoms usually begins with the question: is the lesion central or is it peripheral? The answer commonly emerges from a careful examination of eye movements, especially when the lesion is located in otherwise clinically silent areas of the brain such as the vestibular portions of the cerebellum (flocculus, paraflocculus which is called the tonsils in humans, nodulus, and uvula) and the vestibular nuclei as well as immediately adjacent areas (the perihypoglossal nuclei and the paramedian nuclei and tracts). The neural circuitry that controls vestibular eye movements is intertwined with a larger network within the brainstem and cerebellum that also controls other types of conjugate eye movements. These include saccades and pursuit as well as the mechanisms that enable steady fixation, both straight ahead and in eccentric gaze positions. Navigating through this complex network requires a thorough knowledge about all classes of eye movements to help localize lesions causing a vestibular disorder. Here we review the different classes of eye movements and how to examine them, and then describe common ocular motor findings associated with central vestibular lesions from both a topographic and functional perspective. © 2016 Elsevier B.V. All rights reserved.

  11. Progress toward development of a multichannel vestibular prosthesis for treatment of bilateral vestibular deficiency.

    Science.gov (United States)

    Fridman, Gene Y; Della Santina, Charles C

    2012-11-01

    This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation-inhibition asymmetry, and adapting laboratory MVP prototypes into devices

  12. [The effects of support-proprioceptive deprivation on visual-manual tracking and vestibular function].

    Science.gov (United States)

    Kornilova, L N; Naumov, I A; Glukhikh, D O; Khabarova, E V; Kozlovskaia, I B

    2013-01-01

    To determine the effects of support and proprioceptive afferentation on characteristics of the visual-manual tracking (VMT) we used a model of weightlessness - horizontal "dry" immersion. Altogether 30 subjects who stayed in immersion bath from 5 to 7 days were examined to evaluate the accuracy of VMT in tasks to pursue the jerky (saccadically) and smooth (linear, pendular and circular) movement of a point visual stimulus. Examinations were performed before, during and after immersion using electrooculography (to record eye movements) and a joystick (to record hand movements) with a biological visual feedback - one of the two visible stimuli on the screen matched the current angle of the joystick handle. Computerized visual stimulation programs were presented to subject using a virtual reality glasses. We analyzed time, amplitude and velocity characteristics of the visual and manual tracking (VT and MT), including efficiency ratio (eVT and eMT) and gain (gVT and gMT) as ratios of respectively amplitudes and velocities of eyes/hand movements to the stimulus movement. eVT was significantly decreased in comparison with baseline all the time while subject lied in the immersion bath and until R+4 day after immersion, eMT was significantly decreased only on I-1 and I-3 days in immersion. gVT significantly differed from baseline only on I-3 and I-6 days in immersion and R + 1 day after immersion. We found no significant changes in gMT. Evaluations of the vestibular function (VF) were performed before and after immersion using videooculography approach. We analyzed statical torsional otolith-cervical-ocular reflex (OCOR), dynamical vestibular-cervical-ocular reactions (VCOR), spontaneous eye movements (SpEM), the accuracy of perception of subjective visual vertical (SVV). After immersion 47% of subjects had significant decrease of OCOR with a simultaneous significant increase of VCOR on 37% of subjects as well as significant changes in accuracy of perception of SVV which

  13. Vestibular evaluation in children with otitis media with effusion.

    Science.gov (United States)

    Kolkaila, E A; Emara, A A; Gabr, T A

    2015-04-01

    Fifty per cent of children with serous otitis media may have some balance disturbances. To evaluate vestibular function in children with otitis media with effusion. The control group comprised 25 children with bilateral normal hearing and middle-ear function. The study group consisted of 30 children with bilateral otitis media with effusion; these were divided into 2 subgroups according to air-bone gap size. Measures included the Arabic Dizziness Handicap Inventory, an imbalance evaluation sheet for children, vestibular bedside tests for children, and air- and bone-conducted vestibular-evoked myogenic potential testing. Arabic Dizziness Handicap Inventory scores and some vestibular bedside test results were significantly abnormal, with normal video-nystagmography results, in children with otitis media with effusion. Air-conducted vestibular-evoked myogenic potentials were recorded in 73 per cent of children with otitis media with effusion, with significantly delayed latencies. Bone-conducted vestibular-evoked myogenic potentials were successfully detected in 100 per cent of children with otitis media with effusion with similar results to the control group. The Arabic Dizziness Handicap Inventory and vestibular bedside tests are valuable tools for detecting vestibular impairment in children. Bone-conducted vestibular-evoked myogenic potentials are useful for vestibular system evaluation.

  14. A low-cost video-oculography system for vestibular function testing.

    Science.gov (United States)

    Jihwan Park; Youngsun Kong; Yunyoung Nam

    2017-07-01

    In order to remain in focus during head movements, vestibular-ocular reflex causes eyes to move in the opposite direction to head movement. Disorders of vestibular system decrease vision, causing abnormal nystagmus and dizziness. To diagnose abnormal nystagmus, various studies have been reported including the use of rotating chair tests and videonystagmography. However, these tests are unsuitable for home use due to their high costs. Thus, a low-cost video-oculography system is necessary to obtain clinical features at home. In this paper, we present a low-cost video-oculography system using an infrared camera and Raspberry Pi board for tracking the pupils and evaluating a vestibular system. Horizontal eye movement is derived from video data obtained from an infrared camera and infrared light-emitting diodes, and the velocity of head rotation is obtained from a gyroscope sensor. Each pupil was extracted using a morphology operation and a contour detection method. Rotatory chair tests were conducted with our developed device. To evaluate our system, gain, asymmetry, and phase were measured and compared with System 2000. The average IQR errors of gain, phase and asymmetry were 0.81, 2.74 and 17.35, respectively. We showed that our system is able to measure clinical features.

  15. The intravestibular source of the vestibular aqueduct. II: its structure and function clarified by a developmental study of the intra-skeletal channels of the otic capsule.

    Science.gov (United States)

    Michaels, Leslie; Soucek, Sava; Linthicum, Fred

    2010-04-01

    A developmental histologic study of the otic capsule indicates that it grows a system of lamellar bone with abundant interconnecting intraosseous channels. These include the 'cartilage canals' in the cartilage model, the chondro-osseous and Haversian-like (Volkmann's) canals in the ossified otic capsule, the fissula ante fenestram, which seems to function as a lifelong manufacturer of the latter two channels, and the inner layer (vestibular arch) of the vestibular aqueduct, which is a complex series of Volkmann's canals and microcanals. Chemical changes, possibly produced by breakdown of cells within the channels, may provide a homeostatic environment for the functions of hearing and balance that take place in the endolymphatic fluid. We studied the development of the otic capsule to clarify the cellular appearances that we had previously described in the normal vestibular arch and the changes in that structure in Ménière's disease. Step sections from 84 temporal bones, including those from fetuses, children and adults from a variety of ages were examined histologically. Cartilage canals, bringing blood vessels and mesenchymal cells from perichondrium to the depths of the cartilage model to mediate ossification, are found early in fetal life and disappear when ossification is complete at about 24 weeks. The otic capsule is formed of chondro-osseous canals, which are composed of trabeculae of mineralized cartilage lacunae containing mesenchymal cells that undergo ossification (globuli ossei); also Volkmann's canals (like Haversian canals in long bones but multidirectional), which are produced from osteoblasts. The lumina of the latter frequently link up with chondro-osseous canals. Lamellar bone forms the background of the otic capsule. The fissula ante fenestram is present from early in the cartilage model and then throughout life. It appears to mediate bone production and the new formation of chondro-osseous channels and Volkmann's canals. The internal layer of

  16. Light microscopical study of nitric oxide synthase I-positive neurons, including fibres in the vestibular nuclear complex of the cat.

    Science.gov (United States)

    Papantchev, Vassil; Paloff, Adrian; Christova, Tatiana; Hinova-Palova, Dimka; Ovtscharoff, Wladimir

    2005-01-01

    Nitric oxide is a gaseous neurotransmitter that is synthesized by the enzyme nitric oxide synthase I (NOS I). At present, little is known of NOS I-positive neurons in the vestibular nuclear complex of the cat (VNCc). The aim of the present study was to examine the morphology, distribution patterns and interconnections of NOS I-positive neurons, including fibres in the VNCc. Five adult cats were used as experimental animals. All cats were anaesthetized and perfused transcardially. Brains were removed, postfixed, cut on a freezing microtome and stained in three different ways. Every third section was treated with the Nissl method, other sections were stained either histochemically for NADPH diaphorase or immunohistochemically for NOS I. The atlas of Berman (1928) was used for orientation in the morphometric study. NOS I-positive neurons and fibres were found in all parts of VNCc: medial vestibular nucleus (MVN); lateral vestibular nucleus (LVN); superior vestibular nucleus (SVN); inferior vestibular nucleus (IVN); X, Y, Z groups and Cajal's nucleus. The NOS I-positive neurons were classified according to their size (small, medium-sized, large neurons type I and type II) and their shape (oval, fusiform, triangular, pear-shaped, multipolar and irregular). In every nucleus, a specific neuronal population was observed. In SVN, a large number of interconnections between NOS I-positive neurons were identified. In MVN, chain-like rolls of small neurons were found. Tiny interconnections between MVN and mesencephalic reticular formation were present. Our data provide information on the morphology, distribution patterns and interconnections of NOS I-positive neurons in the VNCc and can be extrapolated to other mammals.

  17. Central vestibular system: vestibular nuclei and posterior cerebellum.

    Science.gov (United States)

    Barmack, Neal H

    2003-06-15

    The vestibular nuclei and posterior cerebellum are the destination of vestibular primary afferents and the subject of this review. The vestibular nuclei include four major nuclei (medial, descending, superior and lateral). In addition, smaller vestibular nuclei include: Y-group, parasolitary nucleus, and nucleus intercalatus. Each of the major nuclei can be subdivided further based primarily on cytological and immunohistochemical histological criteria or differences in afferent and/or efferent projections. The primary afferent projections of vestibular end organs are distributed to several ipsilateral vestibular nuclei. Vestibular nuclei communicate bilaterally through a commissural system that is predominantly inhibitory. Secondary vestibular neurons also receive convergent sensory information from optokinetic circuitry, central visual system and neck proprioceptive systems. Secondary vestibular neurons cannot distinguish between sources of afferent activity. However, the discharge of secondary vestibular neurons can distinguish between "active" and "passive" movements. The posterior cerebellum has extensive afferent and efferent connections with vestibular nuclei. Vestibular primary afferents are distributed to the ipsilateral uvula-nodulus as mossy fibers. Vestibular secondary afferents are distributed bilaterally. Climbing fibers to the cerebellum originate from two subnuclei of the contralateral inferior olive; the dorsomedial cell column and beta-nucleus. Vestibular climbing fibers carry information only from the vertical semicircular canals and otoliths. They establish a coordinate map, arrayed in sagittal zones on the surface of the uvula-nodulus. Purkinje cells respond to vestibular stimulation with antiphasic modulation of climbing fiber responses (CFRs) and simple spikes (SSs). The modulation of SSs is out of phase with the modulation of vestibular primary afferents. Modulation of SSs persists, even after vestibular primary afferents are destroyed by a

  18. MS-27THE IMPACT OF HYPOFRACTIONATED LINAC-BASED STEREOTACTIC RADIOSURGERY UPON EARLY AUDITORY FUNCTIONS IN THE TREATMENT OF VESTIBULAR SCHWANNOMAS

    OpenAIRE

    Wang, Fen; Roy, Amit; Badkul, Rajeev; John, Park; Kumar, Parvesh; Staecker, Hinrich

    2014-01-01

    PURPOSE: To determine the impact of hypofractionated stereotactic radiotherapy (fSRT) scheme upon early auditory functions in the treatment of vestibular schwannomas (VSs). MATERIALS AND METHODS: 21 VS patients treated with a Linac-based frameless fSRT to 25 Gy in 5 daily fractions were retrospectively reviewed. Serial audiometry tests including auditory thresholds and speech discrimination (SD) were conducted prior to fSRT and then at regular intervals post-fSRT to determine the impact of ou...

  19. Balance Screening of Vestibular Function in Subjects Aged 4 Years and Older: A Living Laboratory Experience

    Directory of Open Access Journals (Sweden)

    María Carolina Bermúdez Rey

    2017-11-01

    Full Text Available To better understand the various individual factors that contribute to balance and the relation to fall risk, we performed the modified Romberg Test of Standing Balance on Firm and Compliant Support, with 1,174 participants between 4 and 83 years of age. This research was conducted in the Living Laboratory® at the Museum of Science, Boston. We specifically focus on balance test condition 4, in which individuals stand on memory foam with eyes closed, and must rely on their vestibular system; therefore, performance in this balance test condition provides a proxy for vestibular function. We looked for balance variations associated with sex, race/ethnicity, health factors, and age. We found that balance test performance was stable between 10 and 39 years of age, with a slight increase in the failure rate for participants 4–9 years of age, suggesting a period of balance development in younger children. For participants 40 years and older, the balance test failure rate increased progressively with age. Diabetes and obesity are the two main health factors we found associated with poor balance, with test condition 4 failure rates of 57 and 19%, respectively. An increase in the odds of having fallen in the last year was associated with a decrease in the time to failure; once individuals dropped below a time to failure of 10 s, there was a significant 5.5-fold increase in the odds of having fallen in the last 12 months. These data alert us to screen for poor vestibular function in individuals 40 years and older or suffering from diabetes, in order to undertake the necessary diagnostic and rehabilitation measures, with a focus on reducing the morbidity and mortality of falls.

  20. A balance of form and function: planar polarity and development of the vestibular maculae.

    Science.gov (United States)

    Deans, Michael R

    2013-05-01

    The mechanosensory hair cells of the inner ear have emerged as one of the primary models for studying the development of planar polarity in vertebrates. Planar polarity is the polarized organization of cells or cellular structures in the plane of an epithelium. For hair cells, planar polarity is manifest at the subcellular level in the polarized organization of the stereociliary bundle and at the cellular level in the coordinated orientation of stereociliary bundles between adjacent cells. This latter organization is commonly called Planar Cell Polarity and has been described in the greatest detail for auditory hair cells of the cochlea. A third level of planar polarity, referred to as tissue polarity, occurs in the utricular and saccular maculae; two inner ear sensory organs that use hair cells to detect linear acceleration and gravity. In the utricle and saccule hair cells are divided between two groups that have opposite stereociliary bundle polarities and, as a result, are able to detect movements in opposite directions. Thus vestibular hair cells are a unique model system for studying planar polarity because polarization develops at three different anatomical scales in the same sensory organ. Moreover the system has the potential to be used to dissect functional interactions between molecules regulating planar polarity at each of the three levels. Here the significance of planar polarity on vestibular system function will be discussed, and the molecular mechanisms associated with development of planar polarity at each anatomical level will be reviewed. Additional aspects of planar polarity that are unique to the vestibular maculae will also be introduced. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. [Clinical value of dynamic posturography in the evaluation and rehabilitation of vestibular function of patients with benign paroxysmal positional vertigo].

    Science.gov (United States)

    Zhang, Dao-gong; Fan, Zhao-min; Han, Yue-chen; Yu, Gang; Wang, Hai-bo

    2010-09-01

    To explore the clinical value of dynamic posturography in the evaluation and rehabilitation of vestibular function of patients with benign paroxysmal positional vertigo (BPPV). A total of 48 patients with BPPV of posterior semicircular canal in vertigo clinic of our hospital from May 2007 to December 2008 were retrospectively analyzed in this study. All patients underwent the inspection of caloric test, static posturography, and dynamic posturography. The vestibular tests were performed at two different time points: at onset when patients had typical nystagmus provoked by the Dix-Hallpike maneuver before treatment with the Epley maneuver (canalith repositioning maneuver, CRM), and at one week after treatment with CRM as their nystagmus disappeared. And results at theses two time points were compared. Eight patients whose dynamic balances were still abnormal after CRM accepted vestibular rehabilitation exercise using dynamic posturography, and re-examined 3 weeks later with dynamic posturography. Among 48 cases of BPPV, the abnormal rates of caloric test, static posturography, and dynamic posturography before CRM were 25.0%, 33.3% and 70.8%, respectively. The abnormal rate of dynamic posturography was much higher than that of caloric test or static posturography, and the differences were statistically significant (χ² = 4.84, 7.88; P 0.05). Eight patients whose dynamic balances were still abnormal after CRM, accepted vestibular rehabilitation exercise lasting 3 weeks using dynamic posturography. The dynamic balances were all improved to normal after vestibular rehabilitation. Dynamic posturography can quantitatively analyze postural balance, and is helpful in comprehensive evaluation of the vestibular function of BPPV patients. Impaired balance often presents in patients with BPPV. Treatment of BPPV using the canalith repositioning maneuver results in improved postural stability in static and dynamic posturography. However, not all patients have normal dynamic

  2. Anatomy of the vestibular system: a review.

    Science.gov (United States)

    Khan, Sarah; Chang, Richard

    2013-01-01

    A sense of proper sensory processing of head motion and the coordination of visual and postural movements to maintain equilibrium is critical to everyday function. The vestibular system is an intricate organization that involves multiple levels of sensory processing to achieve this goal. This chapter provides an overview of the anatomical structures and pathways of the vestibular system. The five major vestibular structures are located in the inner ear and include: the utricle, the saccule, and the lateral, superior, and posterior semicircular canals. Hair cells on the neuroepithelium of the peripheral vestibular organs carry sensory impulses to primary processing centers in the brainstem and the cerebellum. These areas send input via ascending and descending projections to coordinate vital reflexes, such as the vestibuloocular reflex and the vestibulospinal reflex, which allow for the proper orientation of the eyes and body in response to head motion. Specific connections regarding higher level cortical vestibular structures are poorly understood. Vestibular centers in the brainstem, cerebellum, and cerebral cortex function to integrate sensory information from the peripheral vestibular organs, visual system, and proprioceptive system to allow for proper balance and orientation of the body in its environment.

  3. Vestibular Stochastic Resonance as a Method to Improve Balance Function: Optimization of Stimulus Characteristics

    Science.gov (United States)

    Mulavara, Ajitkumar; Fiedler, Matthew; Kofman, Igor; Peters, Brian; Wood, Scott; Serrador, Jorge; Cohen, Helen; Reschke, Millard; Bloomberg, Jacob

    2010-01-01

    Stochastic resonance (SR) is a mechanism by which noise can assist and enhance the response of neural systems to relevant sensory signals. Application of imperceptible SR noise coupled with sensory input through the proprioceptive, visual, or vestibular sensory systems has been shown to improve motor function. Specifically, studies have shown that that vestibular electrical stimulation by imperceptible stochastic noise, when applied to normal young and elderly subjects, significantly improved their ocular stabilization reflexes in response to whole-body tilt as well as balance performance during postural disturbances. The goal of this study was to optimize the characteristics of the stochastic vestibular signals for balance performance during standing on an unstable surface. Subjects performed a standardized balance task of standing on a block of 10 cm thick medium density foam with their eyes closed for a total of 40 seconds. Stochastic electrical stimulation was applied to the vestibular system through electrodes placed over the mastoid process behind the ears during the last 20 seconds of the test period. A custom built constant current stimulator with subject isolation delivered the stimulus. Stimulation signals were generated with frequencies in the bandwidth of 1-2 Hz and 0.01-30 Hz. Amplitude of the signals were varied in the range of 0- +/-700 micro amperes with the RMS of the signal increased by 30 micro amperes for each 100 micro amperes increase in the current range. Balance performance was measured using a force plate under the foam block and inertial motion sensors placed on the torso and head segments. Preliminary results indicate that balance performance is improved in the range of 10-25% compared to no stimulation conditions. Subjects improved their performance consistently across the blocks of stimulation. Further the signal amplitude at which the performance was maximized was different in the two frequency ranges. Optimization of the frequency and

  4. Função vestibular no acidente vascular cerebral do território carot��deo Vestibular function in carotid territory stroke patients

    Directory of Open Access Journals (Sweden)

    Anna Paula Batista de Ávila Pires

    2013-02-01

    Full Text Available Pacientes após Acidente Vascular Cerebral (AVC podem apresentar sintomas otoneurológicos. OBJETIVO: Avaliar a função vestibular de pacientes com antecedente pessoal de AVC no território carotídeo. Desenho científico: estudo de coorte histórica com corte transversal. MÉTODO: Quarenta pacientes foram submetidos à anamnese, exame otorrinolaringológico, Dizziness Handicap Inventory e vectoeletronistagmografia. RESULTADOS: Anormalidades discretas dos movimentos sacádicos foram encontradas em 20 pacientes (50,0%; nove referiram desequilíbrio e um tontura. O ganho do rastreio pendular foi anormal em 17 casos (42,5%; seis referiram desequilíbrio e um tontura. Preponderância direcional anormal do nistagmoperrotatório ocorreu em dois casos (5,0%, que referiram desequilíbrio. A prova calórica identificou três casos (7,5% com predomínio labiríntico anormal e dois (5,0% com preponderância direcional anormal do nistagmo; os cinco casos relataram desequilíbrio. Dos 11 pacientes que não referiram manifestações de alteração do equilíbrio corporal, 10 apresentaram alterações nos movimentos sacádicos e no rastreio pendular e um apresentou exame vestibular normal. CONCLUSÃO: Pacientes com antecedente pessoal de AVC no território carotídeo podem apresentar tontura ou desequilíbrio corporal e sinais de comprometimento da motilidade ocular e da função vestibular.Stroke patients may present otoneurological symptoms. OBJECTIVE: To assess the vestibular function of subjects with a history of carotid territory stroke. METHOD: This historical cohort cross sectional study enrolled 40 patients; subjects answered the Dizziness Handicap Inventory, were interviewed and submitted to ENT examination and vectorelectronystagmography. RESULTS: Mild saccadic movement anomalies were seen in 20 patients (50.0%; nine complained of imbalance and dizziness. Abnormal smooth pursuit gain was seen in 17 cases (42.5%; six subjects reported imbalance and

  5. The combination of vestibular impairment and congenital sensorineural hearing loss predisposes patients to ocular anomalies, including Usher syndrome.

    Science.gov (United States)

    Kletke, S; Batmanabane, V; Dai, T; Vincent, A; Li, S; Gordon, K A; Papsin, B C; Cushing, S L; Héon, E

    2017-07-01

    The co-occurrence of hearing impairment and visual dysfunction is devastating. Most deaf-blind etiologies are genetically determined, the commonest being Usher syndrome (USH). While studies of the congenitally deaf population reveal a variable degree of visual problems, there are no effective ophthalmic screening guidelines. We hypothesized that children with congenital sensorineural hearing loss (SNHL) and vestibular impairment were at an increased risk of having USH. A retrospective chart review of 33 cochlear implants recipients for severe to profound SNHL and measured vestibular dysfunction was performed to determine the ocular phenotype. All the cases had undergone ocular examination and electroretinogram (ERG). Patients with an abnormal ERG underwent genetic testing for USH. We found an underlying ocular abnormality in 81.81% (27/33) of cases; of which 75% had refractive errors, and 50% of those patients showed visual improvement with refractive correction. A total of 14 cases (42.42%; 14/33) had generalized rod-cone dysfunction on ERG suggestive of Usher syndrome type 1, confirmed by mutational analysis. This work shows that adding vestibular impairment as a criterion for requesting an eye exam and adding the ERG to detect USH increases the chances of detecting ocular anomalies, when compared with previous literature focusing only on congenital SNHL. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Facial nerve function after vestibular schwannoma surgery following failed conservative management

    DEFF Research Database (Denmark)

    Kaltoft, Mikkel; Stangerup, Sven-Eric; Cayé-Thomasen, Per

    2012-01-01

    patients had normal facial nerve function at the end of observation. Good facial nerve outcome was found in 87 % of patients operated at diagnosis, and in 84 % of patients operated after established tumor growth. For the subgroup of small extrameatal tumors this difference was significant. Pooling all...... patients allocated primarily to conservative management, good facial function was found in 97%, which was significantly better than the result for primary operation (87%). CONCLUSION:: Overall, conservative management of small to medium-sized vestibular schwannomas is the best option with regard...... to preservation of the facial nerve function. Tumor growth during observation is found in only a minor proportion of the patients, and in these cases surgery or irradiation should be performed immediately....

  7. Cochlear Nerve Action Potential Monitoring for Preserving Function of an Unseen Cochlear Nerve in Vestibular Schwannoma Surgery.

    Science.gov (United States)

    Ishikawa, Mami; Kojima, Atsuhiro; Terao, Satoshi; Nagai, Mutsumi; Kusaka, Gen; Naritaka, Heiji

    2017-10-01

    Intraoperative monitoring of cochlear nerve action potential (CNAP) has been used in patients with small vestibular schwannoma (<15 mm) to preserve cochlear nerve function. We performed surgery for a larger vestibular schwannoma under CNAP monitoring with the aim of preserving cochlear nerve function, and compared the data with findings from 10 patients with hemifacial spasm who underwent microvascular decompression surgery. We report the case of a patient with a 26-mm vestibular schwannoma and normal hearing function who underwent neurosurgery under electrophysiological monitoring of the facial and cochlear nerves. Amplitudes of evoked facial muscle responses were maintained at approximately 70% during the operation. The latency of wave V on brainstem auditory evoked potential (BAEP) increased by 0.5 ms, and amplitude was maintained at approximately 70% of the value at the beginning of the operation. Latencies of P1, N1, and P2 on CNAP did not change intraoperatively. These latencies were comparable to those of 10 normal patients with hemifacial spasm. CNAP monitoring proved very useful in confirming the location of the cochlear nerve in the operative field and preserving cochlear nerve function. Both facial nerve function and hearing acuity were completely preserved after tumor removal, and wave V latency on BAEP returned to normal and was maintained in the normal range for at least 2 years. CNAP monitoring is extremely useful for preserving the function of the unseen cochlear nerve during vestibular schwannoma surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. A meta-analysis of surgical treatment for vestibular schwannoma: is hospital volume related to preservation of facial function?

    Science.gov (United States)

    Hastan, Deniz; Vandenbroucke, Jan P; van der Mey, Andel G L

    2009-10-01

    To investigate the relation between hospital volume and preservation ratios of facial function in surgery for vestibular schwannoma. A meta-analysis was conducted on current literature concerning preservation ratios of facial function after surgical resection of vestibular schwannoma. Studies reported by the House-Brackmann grading system for facial function were searched; all studies were published in English in peer-reviewed journals between 1992 and 2007. Articles had to report 1) patients who had surgery for vestibular schwannoma, 2) House-Brackmann grades for facial function, and 3) calendar time and number of procedures. Standard methods for meta-analysis were adapted. Data were pooled by weighing studies according to their accuracy. Results were sorted for low-, moderate-, and high-volume hospitals. Linear relations were quantified by metaregression analysis (n = 5,560). Findings of this meta-analysis suggest that there is a linear relation between hospital volume and preservation ratio of facial function. The concentration of surgical treatment might be a consideration to optimize clinical outcome. Prospective and nationwide registration of surgical results might contribute to more definitive conclusions regarding outcome of vestibular schwannoma surgery.

  9. Regeneration of hair cells in the mammalian vestibular system.

    Science.gov (United States)

    Li, Wenyan; You, Dan; Chen, Yan; Chai, Renjie; Li, Huawei

    2016-06-01

    Hair cells regenerate throughout the lifetime of non-mammalian vertebrates, allowing these animals to recover from hearing and balance deficits. Such regeneration does not occur efficiently in humans and other mammals. Thus, balance deficits become permanent and is a common sensory disorder all over the world. Since Forge and Warchol discovered the limited spontaneous regeneration of vestibular hair cells after gentamicininduced damage in mature mammals, significant efforts have been exerted to trace the origin of the limited vestibular regeneration in mammals after hair cell loss. Moreover, recently many strategies have been developed to promote the hair cell regeneration and subsequent functional recovery of the vestibular system, including manipulating the Wnt, Notch and Atoh1. This article provides an overview of the recent advances in hair cell regeneration in mammalian vestibular epithelia. Furthermore, this review highlights the current limitations of hair cell regeneration and provides the possible solutions to regenerate functional hair cells and to partially restore vestibular function.

  10. [BEHAVIORAL AND FUNCTIONAL VESTIBULAR DISTURBANCES AFTER SPACE FLIGHT. 2. FISHES, AMPHIBIANS AND BIRDS].

    Science.gov (United States)

    Lychakov, D V

    2016-01-01

    The review contains data on functional shifts in fishes, amphibians and birds caused by changes in the otolith system operation after stay under weightlessness conditions. These data are of theoretical and practical significance and are important to resolve some fundamental problems of vestibulogy. The analysis of the results of space experiments has shown that weightlessness conditions do not exert a substantial impact on formation and functional state of the otolith system in embryonic fishes, amphibians and birds developed during space flight. Weightlessness conditions do pot inhibit embryonic development of lower vertebrates but even have rather beneficial effect on it. This is consistent with conclusions concerning development of mammalian fetuses. The experimental results show that weightlessness can cause similar functional and behavioral vestibular shifts both in lower vertebrates and in mammals. For example, immediately after an orbital flight the vestibuloocular reflex in fish larvae and tadpoles (without lordosis) was stronger than in control individuals. A similar shift of the otolith reflex was observed in the majority of cosmonauts after short-term orbital flights. Immediately after landing adult terrestrial vertebrates, as well as human beings, exhibit lower activity levels, worse equilibrium and coordination of movements. Another interesting finding observed after landing of the cosmic apparatus was an unusual looping character of tadpole swimming. It is supposed that the unusual motor activity of animals as well as appearance of illusions in cosmonauts and astronauts after switching from 1 to 0 g have the same nature and are related to the change in character of otolith organs stimulation. Considering this similarity of vestibular reactions, using animals seems rather perspective. Besides it allows applying in experiments various invasive techniques.

  11. Vestibular Evoked Myogenic Potential (VEMP Triggered by Galvanic Vestibular Stimulation (GVS: A Promising Tool to Assess Spinal Cord Function in Schistosomal Myeloradiculopathy.

    Directory of Open Access Journals (Sweden)

    Júlia Fonseca de Morais Caporali

    2016-04-01

    Full Text Available Schistosomal myeloradiculopathy (SMR, the most severe and disabling ectopic form of Schistosoma mansoni infection, is caused by embolized ova eliciting local inflammation in the spinal cord and nerve roots. The treatment involves the use of praziquantel and long-term corticotherapy. The assessment of therapeutic response relies on neurological examination. Supplementary electrophysiological exams may improve prediction and monitoring of functional outcome. Vestibular evoked myogenic potential (VEMP triggered by galvanic vestibular stimulation (GVS is a simple, safe, low-cost and noninvasive electrophysiological technique that has been used to test the vestibulospinal tract in motor myelopathies. This paper reports the results of VEMP with GVS in patients with SMR.A cross-sectional comparative study enrolled 22 patients with definite SMR and 22 healthy controls that were submitted to clinical, neurological examination and GVS. Galvanic stimulus was applied in the mastoid bones in a transcranial configuration for testing VEMP, which was recorded by electromyography (EMG in the gastrocnemii muscles. The VEMP variables of interest were blindly measured by two independent examiners. They were the short-latency (SL and the medium-latency (ML components of the biphasic EMG wave.VEMP showed the components SL (p = 0.001 and ML (p<0.001 delayed in SMR compared to controls. The delay of SL (p = 0.010 and of ML (p = 0.020 was associated with gait dysfunction.VEMP triggered by GVS identified alterations in patients with SMR and provided additional functional information that justifies its use as a supplementary test in motor myelopathies.

  12. Vestibular tributaries to the vein of the vestibular aqueduct

    DEFF Research Database (Denmark)

    Hansen, Jesper Marsner; Qvortrup, Klaus; Friis, Morten

    2010-01-01

    CONCLUSION: The vein of the vestibular aqueduct drains blood from areas extensively lined by vestibular dark cells (VDCs). A possible involvement in the pathogenesis of an impaired endolymphatic homeostasis can be envisioned at the level of the dark cells area. OBJECTIVES: The aim of this study...... was to investigate the vascular relationship between the vein of the vestibular aqueduct and the vestibular apparatus, with focus on the VDCs. METHODS: Sixteen male Wistar rats were divided into groups of 6 and 10. In the first group, 2 µm thick sections including the vein of the vestibular aqueduct, utricle...... relation to the VDCs in the utricle and the crista ampullaris of the lateral semicircular canal in the vestibular apparatus. One major vein emanated from these networks, which emptied into the vein of the vestibular aqueduct. Veins draining the saccule and the common crus of the superior and posterior...

  13. Recent Evidence About the Effectiveness of Vestibular Rehabilitation.

    Science.gov (United States)

    Whitney, Susan L; Alghadir, Ahmad H; Anwer, Shahnawaz

    2016-03-01

    Vestibular rehabilitation of persons with peripheral and central vestibular disorders requires a thorough evaluation and a customized plan of care. Collaboration of the various members of the treatment team optimizes outcomes. Early intervention appears to be better than referring patients who have developed chronic symptoms of balance loss, dizziness, anxiety, and depression. There is a body of emerging evidence that supports that the central nervous system has the capability to reweigh sensory inputs in order to improve function. There continues to be a dearth of knowledge related to how to treat persons with otolithic dysfunction as compared to those with semicircular canal damage. With the use of vestibular rehabilitation, patients are less likely to fall, are less dizzy, balance and gait improve, and quality of life is enhanced. Recent Cochrane reviews and a clinical practice guideline support the use of vestibular rehabilitation for persons with vestibular dysfunction. Typical symptoms and their management including dysregulated gait, falling, fear of falling, increased sway in standing, visual blurring, symptoms with complex visual scenes in the periphery, and weakness are all discussed with ideas for intervention. Any patient with a vestibular disorder may benefit from a trial of vestibular rehabilitation. A discussion of recent evidence and innovations related to vestibular rehabilitation is also included.

  14. Development and regeneration of vestibular hair cells in mammals.

    Science.gov (United States)

    Burns, Joseph C; Stone, Jennifer S

    2017-05-01

    Vestibular sensation is essential for gaze stabilization, balance, and perception of gravity. The vestibular receptors in mammals, Type I and Type II hair cells, are located in five small organs in the inner ear. Damage to hair cells and their innervating neurons can cause crippling symptoms such as vertigo, visual field oscillation, and imbalance. In adult rodents, some Type II hair cells are regenerated and become re-innervated after damage, presenting opportunities for restoring vestibular function after hair cell damage. This article reviews features of vestibular sensory cells in mammals, including their basic properties, how they develop, and how they are replaced after damage. We discuss molecules that control vestibular hair cell regeneration and highlight areas in which our understanding of development and regeneration needs to be deepened. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Vestibular perception following acute unilateral vestibular lesions.

    Directory of Open Access Journals (Sweden)

    Sian Cousins

    Full Text Available Little is known about the vestibulo-perceptual (VP system, particularly after a unilateral vestibular lesion. We investigated vestibulo-ocular (VO and VP function in 25 patients with vestibular neuritis (VN acutely (2 days after onset and after compensation (recovery phase, 10 weeks. Since the effect of VN on reflex and perceptual function may differ at threshold and supra-threshold acceleration levels, we used two stimulus intensities, acceleration steps of 0.5°/s(2 and velocity steps of 90°/s (acceleration 180°/s(2. We hypothesised that the vestibular lesion or the compensatory processes could dissociate VO and VP function, particularly if the acute vertiginous sensation interferes with the perceptual tasks. Both in acute and recovery phases, VO and VP thresholds increased, particularly during ipsilesional rotations. In signal detection theory this indicates that signals from the healthy and affected side are still fused, but result in asymmetric thresholds due to a lesion-induced bias. The normal pattern whereby VP thresholds are higher than VO thresholds was preserved, indicating that any 'perceptual noise' added by the vertigo does not disrupt the cognitive decision-making processes inherent to the perceptual task. Overall, the parallel findings in VO and VP thresholds imply little or no additional cortical processing and suggest that vestibular thresholds essentially reflect the sensitivity of the fused peripheral receptors. In contrast, a significant VO-VP dissociation for supra-threshold stimuli was found. Acutely, time constants and duration of the VO and VP responses were reduced - asymmetrically for VO, as expected, but surprisingly symmetrical for perception. At recovery, VP responses normalised but VO responses remained shortened and asymmetric. Thus, unlike threshold data, supra-threshold responses show considerable VO-VP dissociation indicative of additional, higher-order processing of vestibular signals. We provide evidence of

  16. Vestibular dysfunction in a child with embryonic exposure to accutane.

    Science.gov (United States)

    Westerman, S T; Gilbert, L M; Schondel, L

    1994-05-01

    Children with a history of embryonic exposure to Accutane (isotretinoin) are at great risk for major physical malformations, brain malformations, and decreased intelligence. A case is presented of a 4-year 7-month-old black male with a history of embryonic exposure to Accutane who was born with embryopathy that includes bilateral major ear deformities. The child has a significant bilateral conductive hearing loss, and, in addition, a left sided sensorineural loss. Vestibular function testing revealed evidence of peripheral and central vestibular dysfunction. A course of diphenhydramine hydrochloride and Donnatal (phenobarbital, hyoscyamine sulfate, atropine sulfate, and scopolamine hydrobromide) significantly alleviated the symptoms of vestibular dysfunction. Otologic management of these children should include clinical documentation of the external deformities, evaluation of cochlear function, and early auditory habilitation. Vestibular function should also be evaluated in all children with a history of embryonic exposure to isotretinoin.

  17. Common Vestibular Disorders

    Directory of Open Access Journals (Sweden)

    Dimitrios G. Balatsouras

    2017-01-01

    Full Text Available The three most common vestibular diseases, benign paroxysmal positional vertigo (BPPV, Meniere's disease (MD and vestibular neuritis (VN, are presented in this paper. BPPV, which is the most common peripheral vestibular disorder, can be defined as transient vertigo induced by a rapid head position change, associated with a characteristic paroxysmal positional nystagmus. Canalolithiasis of the posterior semicircular canal is considered the most convincing theory of its pathogenesis and the development of appropriate therapeutic maneuvers resulted in its effective treatment. However, involvement of the horizontal or the anterior canal has been found in a significant rate and the recognition and treatment of these variants completed the clinical picture of the disease. MD is a chronic condition characterized by episodic attacks of vertigo, fluctuating hearing loss, tinnitus, aural pressure and a progressive loss of audiovestibular functions. Presence of endolymphatic hydrops on postmortem examination is its pathologic correlate. MD continues to be a diagnostic and therapeutic challenge. Patients with the disease range from minimally symptomatic, highly functional individuals to severely affected, disabled patients. Current management strategies are designed to control the acute and recurrent vestibulopathy but offer minimal remedy for the progressive cochlear dysfunction. VN is the most common cause of acute spontaneous vertigo, attributed to acute unilateral loss of vestibular function. Key signs and symptoms are an acute onset of spinning vertigo, postural imbalance and nausea as well as a horizontal rotatory nystagmus beating towards the non-affected side, a pathological headimpulse test and no evidence for central vestibular or ocular motor dysfunction. Vestibular neuritis preferentially involves the superior vestibular labyrinth and its afferents. Symptomatic medication is indicated only during the acute phase to relieve the vertigo and nausea

  18. Functional Brain Activation in Response to a Clinical Vestibular Test Correlates with Balance.

    Science.gov (United States)

    Noohi, Fatemeh; Kinnaird, Catherine; DeDios, Yiri; Kofman, Igor S; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar; Seidler, Rachael

    2017-01-01

    The current study characterizes brain fMRI activation in response to two modes of vestibular stimulation: Skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit either a vestibulo-spinal reflex [saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)], or an ocular muscle response [utricle-mediated ocular VEMP (oVEMP)]. Research suggests that the skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for subjects than the high decibel tones required to elicit VEMPs. However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of brain activity. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that pneumatically powered skull taps would elicit a similar pattern of brain activity as shown in previous studies. Our results provide the first evidence of using pneumatically powered skull taps to elicit vestibular activity inside the MRI scanner. A conjunction analysis revealed that skull taps elicit overlapping activation with auditory tone bursts in the canonical vestibular cortical regions. Further, our postural control assessments revealed that greater amplitude of brain activation in response to vestibular stimulation was associated with better balance control for both techniques. Additionally, we found that skull taps elicit more robust vestibular activity compared to auditory tone bursts, with less reported aversive effects, highlighting the utility of this approach for future clinical and basic science research.

  19. Vertigo Perception and Quality of Life in Patients after Surgical Treatment of Vestibular Schwannoma with Pretreatment Prehabituation by Chemical Vestibular Ablation

    Directory of Open Access Journals (Sweden)

    Zdeněk Čada

    2016-01-01

    Full Text Available Surgical removal of vestibular schwannoma causes acute vestibular symptoms, including postoperative vertigo and oscillopsia due to nystagmus. In general, the dominant symptom postoperatively is vertigo. Preoperative chemical vestibular ablation can reduce vestibular symptoms postoperatively. We used 1.0 mL of 40 mg/mL nonbuffered gentamicin in three intratympanic installations over 2 days, 2 months preoperatively in 10 patients. Reduction of vestibular function was measured by the head impulse test and the caloric test. Reduction of vestibular function was found in all gentamicin patient groups. After gentamicin vestibular ablation, patients underwent home vestibular exercising for two months. The control group consisted of 10 patients who underwent only home vestibular training two months preoperatively. Postoperative rates of recovery and vertigo in both groups were evaluated with the Glasgow Benefit Inventory (GBI, the Glasgow Health Status Inventory (GHSI, and the Dizziness Handicap Inventory questionnaires, as well as survey of visual symptoms by specific questionnaire developed by us. There were no statistically significant differences between both groups with regard to the results of questionnaires. Patients who received preoperative gentamicin were more resilient to optokinetic and optic flow stimulation (p<0.05. This trial is registered with clinical study registration number NCT02963896.

  20. Neuropharmacology of Vestibular System Disorders

    OpenAIRE

    Soto, Enrique; Vega, Rosario

    2010-01-01

    This work reviews the neuropharmacology of the vestibular system, with an emphasis on the mechanism of action of drugs used in the treatment of vestibular disorders. Otolaryngologists are confronted with a rapidly changing field in which advances in the knowledge of ionic channel function and synaptic transmission mechanisms have led to the development of new scientific models for the understanding of vestibular dysfunction and its management. In particular, there have been recent advances in...

  1. Using Low Levels of Stochastic Vestibular Stimulation to Improve Balance Function.

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    Rahul Goel

    Full Text Available Low-level stochastic vestibular stimulation (SVS has been associated with improved postural responses in the medio-lateral (ML direction, but its effect in improving balance function in both the ML and anterior-posterior (AP directions has not been studied. In this series of studies, the efficacy of applying low amplitude SVS in 0-30 Hz range between the mastoids in the ML direction on improving cross-planar balance function was investigated. Forty-five (45 subjects stood on a compliant surface with their eyes closed and were instructed to maintain a stable upright stance. Measures of stability of the head, trunk, and whole body were quantified in ML, AP and combined APML directions. Results show that binaural bipolar SVS given in the ML direction significantly improved balance performance with the peak of optimal stimulus amplitude predominantly in the range of 100-500 μA for all the three directions, exhibiting stochastic resonance (SR phenomenon. Objective perceptual and body motion thresholds as estimates of internal noise while subjects sat on a chair with their eyes closed and were given 1 Hz bipolar binaural sinusoidal electrical stimuli were also measured. In general, there was no significant difference between estimates of perceptual and body motion thresholds. The average optimal SVS amplitude that improved balance performance (peak SVS amplitude normalized to perceptual threshold was estimated to be 46% in ML, 53% in AP, and 50% in APML directions. A miniature patch-type SVS device may be useful to improve balance function in people with disabilities due to aging, Parkinson's disease or in astronauts returning from long-duration space flight.

  2. A neuroscientific account of how vestibular disorders impair bodily self-consciousness

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    Christophe eLopez

    2013-12-01

    Full Text Available The consequences of vestibular disorders on balance, oculomotor control and self-motion perception have been extensively described in humans and animals. More recently, vestibular disorders have been related to cognitive deficits in spatial navigation and memory tasks. Less frequently, abnormal bodily perceptions have been described in patients with vestibular disorders. Altered forms of bodily self-consciousness include distorted body image and body schema, disembodied self-location (out-of-body experience, altered sense of agency, as well as more complex experiences of dissociation and detachment from the self (depersonalization. In this article, I suggest that vestibular disorders create sensory conflict or mismatch in multisensory brain regions, producing perceptual incoherence and abnormal body and self perceptions. This hypothesis is based on recent functional mapping of the human vestibular cortex, showing vestibular projections to the primary and secondary somatosensory cortex and in several multisensory areas found to be crucial for bodily self-consciousness.

  3. Vestibular animal models: contributions to understanding physiology and disease.

    Science.gov (United States)

    Straka, Hans; Zwergal, Andreas; Cullen, Kathleen E

    2016-04-01

    Our knowledge of the vestibular sensory system, its functional significance for gaze and posture stabilization, and its capability to ensure accurate spatial orientation perception and spatial navigation has greatly benefitted from experimental approaches using a variety of vertebrate species. This review summarizes the attempts to establish the roles of semicircular canal and otolith endorgans in these functions followed by an overview of the most relevant fields of vestibular research including major findings that have advanced our understanding of how this system exerts its influence on reflexive and cognitive challenges encountered during daily life. In particular, we highlight the contributions of different animal models and the advantage of using a comparative research approach. Cross-species comparisons have established that the morpho-physiological properties underlying vestibular signal processing are evolutionarily inherent, thereby disclosing general principles. Based on the documented success of this approach, we suggest that future research employing a balanced spectrum of standard animal models such as fish/frog, mouse and primate will optimize our progress in understanding vestibular processing in health and disease. Moreover, we propose that this should be further supplemented by research employing more "exotic" species that offer unique experimental access and/or have specific vestibular adaptations due to unusual locomotor capabilities or lifestyles. Taken together this strategy will expedite our understanding of the basic principles underlying vestibular computations to reveal relevant translational aspects. Accordingly, studies employing animal models are indispensible and even mandatory for the development of new treatments, medication and technical aids (implants) for patients with vestibular pathologies.

  4. Trigeminal, Visceral and Vestibular Inputs May Improve Cognitive Functions by Acting through the Locus Coeruleus and the Ascending Reticular Activating System: A New Hypothesis

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    Vincenzo De Cicco

    2018-01-01

    Full Text Available It is known that sensory signals sustain the background discharge of the ascending reticular activating system (ARAS which includes the noradrenergic locus coeruleus (LC neurons and controls the level of attention and alertness. Moreover, LC neurons influence brain metabolic activity, gene expression and brain inflammatory processes. As a consequence of the sensory control of ARAS/LC, stimulation of a sensory channel may potential influence neuronal activity and trophic state all over the brain, supporting cognitive functions and exerting a neuroprotective action. On the other hand, an imbalance of the same input on the two sides may lead to an asymmetric hemispheric excitability, leading to an impairment in cognitive functions. Among the inputs that may drive LC neurons and ARAS, those arising from the trigeminal region, from visceral organs and, possibly, from the vestibular system seem to be particularly relevant in regulating their activity. The trigeminal, visceral and vestibular control of ARAS/LC activity may explain why these input signals: (1 affect sensorimotor and cognitive functions which are not directly related to their specific informational content; and (2 are effective in relieving the symptoms of some brain pathologies, thus prompting peripheral activation of these input systems as a complementary approach for the treatment of cognitive impairments and neurodegenerative disorders.

  5. Prophylactic treatment of vestibular migraine

    OpenAIRE

    Salmito, Márcio Cavalcante; Duarte, Juliana Antoniolli; Morganti, Lígia Oliveira Golçalves; Brandão, Priscila Valéria Caus; Nakao, Bruno Higa; Villa, Thais Rodrigues; Ganança,Fernando Freitas

    2017-01-01

    Abstract Introduction: Vestibular migraine (VM) is now accepted as a common cause of episodic vertigo. Treatment of VM involves two situations: the vestibular symptom attacks and the period between attacks. For the latter, some prophylaxis methods can be used. The current recommendation is to use the same prophylactic drugs used for migraines, including β-blockers, antidepressants and anticonvulsants. The recent diagnostic definition of vestibular migraine makes the number of studies on its ...

  6. Effect of different modes of therapy on vestibular and balance dysfunction in Parkinson’s disease

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    Wafaa Abdel-Hay El-Kholy

    2015-07-01

    Conclusions: Since patients with PD receiving physiotherapy in conjunction with medical treatment showed better control of their vestibular and balance functions, efforts should be directed to start physiotherapy including vestibular rehabilitation as early as possible in order to improve balance, thus increasing independence in daily life activities.

  7. Treatment of Vestibular Dysfunction Using a Portable Simulator

    Science.gov (United States)

    2015-04-01

    Project Major Goal 1 - Develop a portable stimulator which can be worn continuously and used to improve vestibular function (April 2014 to June 2016...AD______________ AWARD NUMBER: W81XWH-14-2-0012 TITLE: TREATMENT OF VESTIBULAR DYSFUNCTION USING A PORTABLE STIMULATOR PRINCIPAL...hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and

  8. Correlação entre equilíbrio corporal e capacidade funcional de idosos com disfunções vestibulares crônicas Correlation between the body balance and functional capacity from elderly with chronic vestibular disorders

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    Raquel Ferreira de Sousa

    2011-12-01

    Full Text Available As doenças vestibulares são frequentes na população idosa, resultando, principalmente, em tontura e desequilíbrio corporal, sintomas que podem prejudicar as atividades de vida diária. OBJETIVO: Estudar a correlação entre equilíbrio corporal e a capacidade funcional e a comparação entre risco de queda, ocorrência de queda e a capacidade funcional de idosos com disfunções vestibulares crônicas. MATERIAL E MÉTODO: Forma de estudo transversal, clínico e experimental com 50 idosos, de 60 a 86 anos, com vestibulopatias periféricas crônicas. Estes idosos foram submetidos à avaliação do equilíbrio por meio do Dynamic Gait Index (DGI e à avaliação da capacidade funcional, por meio da Medida de Independência Funcional (MIF. Os dados obtidos foram submetidos ao teste de correlação de Spearman e aos de comparação de Mann-Whitney e Kruskal-Wallis, sendo considerado α=5% (0,05. RESULTADOS: Verificou-se correlação positiva entre o escore total do DGI e todas as pontuações da MIF, especialmente a MIF total (r=0,447; pVestibular disorders are common among the elderly, mainly resulting in dizziness and imbalance - symptoms which can impact daily routine activities. AIM: To study the correlation between body balance and functional capacity and a comparison of risk of falls, actual falls and the functional capacity of the elderly with chronic vestibular dysfunctions. MATERIALS AND METHODS: A cross-sectional, clinical and experimental study with 50 senior citizens - 60 to 86 years, with chronic peripheral vestibular dysfunction. These participants underwent body balance assessment by the Dynamic Gait Index (DGI and functional capacity assessment by the Functional Independence Measure (FIM. The data was tested using the Spearman correlation and comparison tests, Mann-Whitney and Kruskal- Wallis, being α=5% (0.05. RESULTS: There was a significant correlation between the total DGI score and all FIM scores, especially the total score

  9. Complications of Microsurgery of Vestibular Schwannoma

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    Jan Betka

    2014-01-01

    Full Text Available Background. The aim of this study was to analyze complications of vestibular schwannoma (VS microsurgery. Material and Methods. A retrospective study was performed in 333 patients with unilateral vestibular schwannoma indicated for surgical treatment between January 1997 and December 2012. Postoperative complications were assessed immediately after VS surgery as well as during outpatient followup. Results. In all 333 patients microsurgical vestibular schwannoma (Koos grade 1: 12, grade 2: 34, grade 3: 62, and grade 4: 225 removal was performed. The main neurological complication was facial nerve dysfunction. The intermediate and poor function (HB III–VI was observed in 124 cases (45% immediately after surgery and in 104 cases (33% on the last followup. We encountered disordered vestibular compensation in 13%, permanent trigeminal nerve dysfunction in 1%, and transient lower cranial nerves (IX–XI deficit in 6%. Nonneurological complications included CSF leakage in 63% (lateral/medial variant: 99/1%, headache in 9%, and intracerebral hemorrhage in 5%. We did not encounter any case of meningitis. Conclusions. Our study demonstrates that despite the benefits of advanced high-tech equipment, refined microsurgical instruments, and highly developed neuroimaging technologies, there are still various and significant complications associated with vestibular schwannomas microsurgery.

  10. Recovery of dynamic visual acuity in bilateral vestibular hypofunction.

    Science.gov (United States)

    Herdman, Susan J; Hall, Courtney D; Schubert, Michael C; Das, Vallabh E; Tusa, Ronald J

    2007-04-01

    To determine the effect of vestibular exercises on the recovery of visual acuity during head movement in patients with bilateral vestibular hypofunction (BVH). Prospective, randomized, double-blinded study. Outpatient clinic, academic setting. Thirteen patients with BVH, aged 47 to 73 years. One group (8 patients) performed vestibular exercises designed to enhance remaining vestibular function, and the other (5 patients) performed placebo exercises. Measurements of dynamic visual acuity (DVA) during predictable head movements using a computerized test; measurement of intensity of oscillopsia using a visual analog scale. As a group, patients who performed vestibular exercises showed a significant improvement in DVA (P = .001), whereas those performing placebo exercises did not (P = .07). Only type of exercise (ie, vestibular vs placebo) was significantly correlated with change in DVA. Other factors examined, including age, time from onset, initial DVA, and complaints of oscillopsia and disequilibrium, were not significantly correlated with change in DVA. Change in oscillopsia did not correlate with change in DVA. Use of vestibular exercises is the main factor involved in recovery of DVA in patients with BVH. We theorize that exercises may foster the use of centrally programmed eye movements that could substitute for the vestibulo-ocular reflex. clinicaltrials.gov Identifier: NCT00411216.

  11. The Use of Computer-Assisted Home Exercises to Preserve Physical Function after a Vestibular Rehabilitation Program: A Randomized Controlled Study

    DEFF Research Database (Denmark)

    Brandt, Michael Smærup; Læssøe, Uffe; Grönvall, Erik

    2016-01-01

    Objective. The purpose of this study was to evaluate whether elderly patients with vestibular dysfunction are able to preserve physical functional level, reduction in dizziness, and the patient's quality of life when assistive computer technology is used in comparison with printed instructions...... their high functional level indicating that the elderly should not necessarily exercise for the first three months after termination of the training in the outpatient clinic. Conclusion. Elderly vestibular dysfunction patients exercising at home seem to maintain their functional level, level of dizziness...

  12. The Effect of Otic Melanocyte Destruction on Auditory and Vestibular Function: a Study on Vitiligo Patients

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    Parvane Mahdi

    2016-03-01

    Full Text Available The hallmark of vitiligo is the disappearance of melanocytes from the skin. As a result, of melanocytes presence in the auditory and vestibular apparatus, the involvement of these systems in vitiligo which targets the melanocytes of the whole body is possible; suggesting that vitiligo is a systemic disease rather than a purely cutaneous problem. A total of 21 patients with vitiligo were enrolled in this study. A group of 20 healthy subjects served as a control group. Pure tone audiometry (PTA, auditory brainstem responses (ABR and vestibular evoked myogenic potentials (VEMP were carried out in all participants. High frequency sensory neural hearing loss was seen in 8 (38.09% patients. ABR analysis revealed 10 (47.61% had an abnormal increase in latency of wave III, and 6 (28.57% had an abnormal prolongation of IPL I-III, however, regarding our VEMP findings, there were no recorded responses on left ear of 1 (4.76% patient and latency of p13 was prolonged in 5(23.80% patients. There was no correlation between ages, duration of disease, and any of the recorded parameters (P>0.05. In the present survey, we highlighted the auditory and vestibular involvement in vitiligo patients.

  13. Fatores associados ao equilíbrio funcional em idosos com disfunção vestibular crônica Functional balance associated factors in the elderly with chronic vestibular disorder

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    Juliana Maria Gazzola

    2006-10-01

    Full Text Available Tarefas do dia-a-dia podem ser muito desafiadoras para o equilíbrio do idoso. OBJETIVO: Verificar a associação entre equilíbrio funcional, avaliado pela Berg Balance Scale (BBS e os dados sociodemográficos, clínicos e de mobilidade (Timed up and go test - TUGT, Dynamic Gait Index - DGI em idosos vestibulopatas crônicos. MATERIAL E MÉTODO: Estudo de casos com 120 idosos com diagnóstico de disfunção vestibular crônica. Foram utilizados os testes de Mann-Whitney, Kruskal-Wallis seguido do teste de Dunn e Coeficiente de Correlação de Spearman. RESULTADOS: Ocorreram associações =-0,354; e correlações significantes entre a pontuação total da BBS e idade (pDaily activities can be challenging for the elderly. AIM: To study the association between functional balance, evaluated by the Berg Balance Scale (BBS, sociodemographics, clinical and mobilility (Timed up and go test - TUGT, Dynamic Gait Index - DGI variables in the elderly with chronic vestibular disorder. MATERIALS AND METHODS: A series study with one hundred and twenty elderly with chronic vestibular disorder. We performed the Mann-Whitney test, the Kruskal-Wallis test followed by Dunn test and the Spearman Coefficient (. RESULTS: Statistically significant associations and correlations were observed between total BBS score and age (=-0.354; p<0.001, age group (p<0.001, number off illnesses (p=0.030, number of illnesses (=-0.287; p=0.001, number of medications (p=0.014, number of medications (=-0.274; p=0.002, recurrent falls (p=0.010, tendency to fall (p=0.002, topographic diagnosis of central vestibular disorder (p<0.001 and periodicity of dizziness (p=0.039, TUGT (=-0.709; p<0.001 and DGI (=-0.748; p<0.001. CONCLUSIONS: Functional balance in the elderly with chronic vestibular disorders evaluated by the BBS is worse when associated with aging, with a more advanced age group (80 years or more, increasing number of illnesses, presence of five or more

  14. Vestibular compensation following vestibular neurotomy.

    Science.gov (United States)

    Devèze, A; Montava, M; Lopez, C; Lacour, M; Magnan, J; Borel, L

    2015-09-01

    Four studies assessing vestibular compensation in Menière's disease patients undergoing unilateral vestibular neurotomy, using different analysis methods, are reviewed, with a focus on the different strategies used by patients according to their preoperative sensory preference. Four prospective studies performed in a university tertiary referral center were reviewed, measuring the pattern of vestibular compensation in Menière's disease patients before and after unilateral vestibular neurotomy on various assessment protocols: postural syndrome assessed on static posturography and gait analysis; perceptual syndrome assessed on subjective visual vertical perception; and oculomotor syndrome assessed on ocular cyclotorsion. Vestibular compensation occurred at variable intervals depending on the parameter investigated. Open-eye postural control and gait/walking returned to normal one month after neurotomy. Fine balance analysis found that visual perception of the vertical and ocular cyclotorsion impairment persisted at long-term follow-up. Clinical postural disturbance persisted only when visual afferents were cut off (eyes closed). These impairments were the expression of a postoperative change in postural strategy related to the new use of visual and non-visual references. Understanding pre-operative interindividual variation in balance strategy is critical to screening for postural instability and tailoring vestibular rehabilitation. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. Vestibular pathways involved in cognition

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    Martin eHitier

    2014-07-01

    Full Text Available Recent discoveries have emphasized the role of the vestibular system in cognitive processes such as memory, spatial navigation and bodily self-consciousness. A precise understanding of the vestibular pathways involved is essential to understand the consequences of vestibular diseases for cognition, as well as develop therapeutic strategies to facilitate recovery. The knowledge of the vestibular cortical projections areas, defined as the cortical areas activated by vestibular stimulation, has dramatically increased over the last several years from both anatomical and functional points of view. Four major pathways have been hypothesized to transmit vestibular information to the vestibular cortex: 1 the vestibulo-thalamo-cortical pathway, which probably transmits spatial information about the environment via the parietal, entorhinal and perirhinal cortices to the hippocampus and is associated with spatial representation and self-versus object motion distinctions; 2 the pathway from the dorsal tegmental nucleus via the lateral mammillary nucleus, the anterodorsal nucleus of the thalamus to the entorhinal cortex, which transmits information for estimations of the head direction; 3 the pathway via the nucleus reticularis pontis oralis, the supramammillary nucleus and the medial septum to the hippocampus, which transmits information supporting hippocampal theta rhythm and memory; and 4 a possible pathway via the cerebellum, and the ventral lateral nucleus of the thalamus (perhaps to the parietal cortex, which transmits information for spatial learning. Finally a new pathway is hypothesized via the basal ganglia, potentially involved in spatial learning and spatial memory. From these pathways, progressively emerges the anatomical network of vestibular cognition.

  16. Hearing preservation in the resection of vestibular schwannomas: patterns of hearing preservation and patient-assessed hearing function.

    Science.gov (United States)

    Wind, Joshua J; Leonetti, John P; Raffin, Michael J M; Pisansky, Marc T; Herr, Brian; Triemstra, Justin D; Anderson, Douglas E

    2011-05-01

    No extant literature documents the analysis of patient perceptions of hearing as a corollary to objective audiometric measures in patients with vestibular schwannoma (VS), or acoustic neuroma. Therefore, using objective audiometric data and patient perceptions of hearing function as outlined on a questionnaire, the authors evaluated the hearing of patients who underwent VS resection. This investigation involved a retrospective review of 176 patients who had undergone VS resections in which hearing preservation was a goal. Both pre- and postoperative audiometry, expressed as a speech discrimination score (SDS) and pure tone threshold average (PTA), were performed, and the results were analyzed. Intraoperative auditory brainstem responses were also recorded. Eighty-seven of the patients (49.4%) completed a postoperative questionnaire designed to assess hearing function in a variety of social and auditory situations. Multiple linear regression analyses were completed to compare available audiometric results with questionnaire responses for each patient. One hundred forty-two patients (80.7%) had PTA and SDS audiometric data pertaining to the surgically treated ear; 94 of these patients (66.2%) had measurable postoperative hearing, as defined by a PTA 0%. Eighty-seven patients (49.4%) completed the retrospective questionnaire, and 74 of them had complete audiometric data and thus were included in a comparative analysis. Questionnaire data showed major postoperative subjective hearing decrements, even among patients with the same pre- and postoperative objective audiometric hearing status. Moreover, the subscore reflecting hearing while exposed to background noise, or the "cocktail party effect," characterized the most significant patient-perceived hearing deficit following VS resection. The authors' analysis of a patient-perceived hearing questionnaire showed that hearing during exposure to background noise, or the cocktail party effect, represents a significant

  17. Neuropharmacological Targets for Drug Action in Vestibular Sensory Pathways.

    Science.gov (United States)

    Lee, Choongheon; Jones, Timothy A

    2017-09-01

    The use of pharmacological agents is often the preferred approach to the management of vestibular dysfunction. In the vestibular sensory pathways, the sensory neuroepithelia are thought to be influenced by a diverse number of neuroactive substances that may act to enhance or inhibit the effect of the primary neurotransmitters [i.e., glutamate (Glu) and acetylcholine (ACh)] or alter their patterns of release. This review summarizes various efforts to identify drug targets including neurotransmitter and neuromodulator receptors in the vestibular sensory pathways. Identifying these receptor targets provides a strategic basis to use specific pharmacological tools to modify receptor function in the treatment and management of debilitating balance disorders. A review of the literature reveals that most investigations of the neuropharmacology of peripheral vestibular function have been performed using in vitro or ex vivo animal preparations rather than studying drug action on the normal intact vestibular system in situ. Such noninvasive approaches could aid the development of more accurate and effective intervention strategies for the treatment of dizziness and vertigo. The current review explores the major neuropharmacological targets for drug action in the vestibular system.

  18. The vestibular implant: Quo vadis?

    Directory of Open Access Journals (Sweden)

    Raymond eVan De Berg

    2011-08-01

    Full Text Available AbstractObjective: to assess the progress of the development of the vestibular implant and its feasibility short-term. Data sources: a search was performed in Pubmed, Medline and Embase. Key words used were vestibular prosth* and vestibular implant. The only search limit was language: English or Dutch. Additional sources were medical books, conference lectures and our personal experience with per-operative vestibular stimulation in patients selected for cochlear implantation.Study selection: all studies about the vestibular implant and related topics were included and evaluated by two reviewers. No study was excluded since every study investigated different aspects of the vestibular implant. Data extraction and synthesis: data was extracted by the first author from selected reports, supplemented by additional information, medical books conference lectures. Since each study had its own point of interest with its own outcomes, it was not possible to compare data of different studies. Conclusion: to use a basic vestibular implant in humans seems feasible in the very near future. Investigations show that electric stimulation of the canal nerves induces a nystagmus which corresponds to the plane of the canal which is innervated by the stimulated nerve branch. The brain is able to adapt to a higher baseline stimulation, while still reacting on a dynamic component. The best response will be achieved by a combination of the optimal stimulus (stimulus profile, stimulus location, precompensation, complemented by central vestibular adaptation. The degree of response will probably vary between individuals, depending on pathology and their ability to adapt.

  19. Current and Future Management of Bilateral Loss of Vestibular Sensation – An update on the Johns Hopkins Multichannel Vestibular Prosthesis Project

    Science.gov (United States)

    Della Santina, Charles C.; Migliaccio, Americo A.; Hayden, Russell; Melvin, Thuy-Anh; Fridman, Gene Y.; Chiang, Bryce; Davidovics, Natan S.; Dai, Chenkai; Carey, John P.; Minor, Lloyd B.; Anderson, Iee-Ching; Park, HongJu; Lyford-Pike, Sofia; Tang, Shan

    2012-01-01

    Bilateral loss of vestibular sensation can disable individuals whose vestibular hair cells are injured by ototoxic medications, infection, Ménière’s disease or other insults to the labyrinth including surgical trauma during cochlear implantation. Without input to vestibulo-ocular and vestibulo-spinal reflexes that normally stabilize the eyes and body, affected patients suffer blurred vision during head movement, postural instability, and chronic disequilibrium. While individuals with some residual sensation often compensate for their loss through rehabilitation exercises, those who fail to do so are left with no adequate treatment options. An implantable neuroelectronic vestibular prosthesis that emulates the normal labyrinth by sensing head movement and modulating activity on appropriate branches of the vestibular nerve could significantly improve quality of life for these otherwise chronically dizzy patients. This brief review describes the impact and current management of bilateral loss of vestibular sensation, animal studies supporting the feasibility of prosthetic vestibular stimulation, and a vestibular prosthesis designed to restore sensation of head rotation in all directions. Similar to a cochlear implant in concept and size, the Johns Hopkins Multichannel Vestibular Prosthesis (MVP) includes miniature gyroscopes to sense head rotation, a microcontroller to process inputs and control stimulus timing, and current sources switched between pairs of electrodes implanted within the vestibular labyrinth. In rodents and rhesus monkeys rendered bilaterally vestibular-deficient via treatment with gentamicin and/or plugging of semicircular canals, the MVP partially restores the vestibulo-ocular reflex for head rotations about any axis of rotation in 3-dimensional space. Our efforts now focus on addressing issues prerequisite to human implantation, including refinement of electrode designs and surgical technique to enhance stimulus selectivity and preserve

  20. Neuroimaging to detect cortical projection of vestibular response to caloric stimulation in young and older adults using functional near-infrared spectroscopy (fNIRS).

    Science.gov (United States)

    Karim, H T; Fuhrman, S I; Furman, J M; Huppert, T J

    2013-08-01

    Functional near-infrared spectroscopy (fNIRS) is a non-invasive and portable neuroimaging technique. The method uses non-ionizing laser light in the range of red to near-infrared to detect changes in cerebral blood oxygenation. In this study, we used fNIRS to investigate cortical hemodynamic changes in the temporo-parietal and frontal regions during caloric vestibular stimulation. Caloric stimulation has previously been investigated using functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), which serves as a validation of the fNIRS imaging modality toward the measurement of vestibular related brain regions. To date, only a single study has used fNIRS during caloric irrigations, which observed blood volume changes in the temporal-parietal area in healthy younger subjects. In this current study, fNIRS was used to measure cortical vestibular activation in 10 right-handed younger subjects (5 male and 5 female, age 25+/-6 years) and 10 right-handed older subjects (6 male and 4 female, age 74+/-5 years). We investigated both warm (44 °C) and cool (30 °C) unilateral caloric vestibular stimulation. Consistent with previous reports, we found that warm (44 °C) caloric irrigation caused a bilateral activation. In addition, we found that cool (30 °C) caloric irrigation caused contralateral activation of the temporo-parietal area. This study is the first to investigate age effects of the caloric stimulation on brain activity. We found that the older subjects had stronger bilateral effects than the younger subjects. Our results confirm previous fMRI and PET studies that showed cortical activation during caloric vestibular irrigation is dependent on side of irrigation, and temperature of irrigation. Furthermore, our results demonstrate that fNIRS is a viable technique in measuring cortical effects during vestibular tasks. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Children with attention deficit hyperactivity disorder have impaired balance function: involvement of somatosensory, visual, and vestibular systems.

    Science.gov (United States)

    Shum, Selina B M; Pang, Marco Y C

    2009-08-01

    To compare standing balance performance and sensory organization of balance control in children with attention deficit hyperactivity disorder (combined type) (ADHD-C) and typically developing children. School-aged children (n = 43) with ADHD-C and 50 age- and sex-matched typically developing children participated in the study. Sensory organization of standing balance was evaluated using the Sensory Organization Test (SOT). In addition to the composite equilibrium score, somatosensory, vestibular, and visual ratios, which were indicators of the ability of the child to use information from the respective sensory systems to maintain balance, were computed. Multivariate analysis of covariance (MANCOVA) was used to compare the outcome variables between the 2 groups while controlling for physical activity level. MANCOVA revealed that children with ADHD-C had significantly lower composite equilibrium scores (P visual ratios (P = .001) than control children, by 10.3%, 2.1%, 15.6%, and 16.0%, respectively. Children with ADHD-C had significant deficits in standing balance performance in all conditions that included a disruption of sensory signals. The visual system tends to be more involved in contributing to the balance deficits in children with ADHD-C than the somatosensory and vestibular systems.

  2. The cognitive neurology of the vestibular system.

    Science.gov (United States)

    Seemungal, Barry M

    2014-02-01

    The aim is to reappraise the current state about what we know of vestibular cognition. The review focuses on cognition and perception, and hence the stress on human studies. In addition, the cerebral cortex is the main but not exclusive brain region of interest. There is a brief mention of vestibular ocular function if only to demonstrate the differential processing between reflex and perception. The effect of vestibular activation on some aspects of cognition, for example neglect, is not reviewed, as there have been no recent landmark findings in this area. The vestibular cerebellum is pivotal in the differential gating of vestibular perceptual and ocular signals to the cerebral cortex. The neuroanatomical correlates mediating vestibular sensations of self-motion ('am I moving?') and spatial orientation ('where am I now?') are distinct. Vestibular-motion perception is supported by a widespread white matter network. Vestibular activation specifically reduces visual motion cortical excitability, whereas other visual cortical regions show an increase in excitability. As the vestibular ocular reflex (VOR) and self-motion perception can be uncoupled both behaviourally and in neural correlate, deficits underlying vestibular patients' symptoms may not be revealed by simple VOR assessment. Given the pivotal cerebellar role in gating vestibular signals to perceptual regions, modulating mechanisms of cerebellar plasticity, for example by combining training with medication or brain stimulation, may prove fruitful in treating the symptoms of chronic dizzy patients.

  3. Vestibular Rehabilitation for Peripheral Vestibular Hypofunction: An Evidence-Based Clinical Practice Guideline: FROM THE AMERICAN PHYSICAL THERAPY ASSOCIATION NEUROLOGY SECTION.

    Science.gov (United States)

    Hall, Courtney D; Herdman, Susan J; Whitney, Susan L; Cass, Stephen P; Clendaniel, Richard A; Fife, Terry D; Furman, Joseph M; Getchius, Thomas S D; Goebel, Joel A; Shepard, Neil T; Woodhouse, Sheelah N

    2016-04-01

    Uncompensated vestibular hypofunction results in postural instability, visual blurring with head movement, and subjective complaints of dizziness and/or imbalance. We sought to answer the question, "Is vestibular exercise effective at enhancing recovery of function in people with peripheral (unilateral or bilateral) vestibular hypofunction?" A systematic review of the literature was performed in 5 databases published after 1985 and 5 additional sources for relevant publications were searched. Article types included meta-analyses, systematic reviews, randomized controlled trials, cohort studies, case control series, and case series for human subjects, published in English. One hundred thirty-five articles were identified as relevant to this clinical practice guideline. Based on strong evidence and a preponderance of benefit over harm, clinicians should offer vestibular rehabilitation to persons with unilateral and bilateral vestibular hypofunction with impairments and functional limitations related to the vestibular deficit. Based on strong evidence and a preponderance of harm over benefit, clinicians should not include voluntary saccadic or smooth-pursuit eye movements in isolation (ie, without head movement) as specific exercises for gaze stability. Based on moderate evidence, clinicians may offer specific exercise techniques to target identified impairments or functional limitations. Based on moderate evidence and in consideration of patient preference, clinicians may provide supervised vestibular rehabilitation. Based on expert opinion extrapolated from the evidence, clinicians may prescribe a minimum of 3 times per day for the performance of gaze stability exercises as 1 component of a home exercise program. Based on expert opinion extrapolated from the evidence (range of supervised visits: 2-38 weeks, mean = 10 weeks), clinicians may consider providing adequate supervised vestibular rehabilitation sessions for the patient to understand the goals of the program

  4. [Effectiveness of Self-efficacy Promoting Vestibular Rehabilitation Program for Patients with Vestibular Hypofunction].

    Science.gov (United States)

    Lee, Hyun Jung; Choi-Kwon, Smi

    2016-10-01

    In this study an examination was done of the effect of self-efficacy promoting vestibular rehabilitation (S-VR) on dizziness, exercise selfefficacy, adherence to vestibular rehabilitation (VR), subjective and objective vestibular function, vestibular compensation and the recurrence of dizziness in patients with vestibular hypofunction. This was a randomized controlled study. Data were collected 3 times at baseline, 4 and 8 weeks after beginning the intervention. Outcome measures were level of dizziness, exercise self-efficacy, and level of adherence to VR. Subjective and objective vestibular function, vestibular compensation and the recurrence of dizziness were also obtained. Data were analyzed using Windows SPSS 21.0 program. After 4 weeks of S-VR, there was no difference between the groups for dizziness, subjective and objective vestibular functions. However, exercise self-efficacy and adherence to VR were higher in the experimental group than in the control group. After 8 weeks of S-VR, dizziness (p=.018) exercise self-efficacy (pVR (pVR is effective in reducing dizziness, and improving exercise self-efficacy, subjective vestibular function and adherence to VR. Objective vestibular function and vestibular compensation were also improved in the experimental group at the end of 8 weeks of S-VR.

  5. Role of the insula and vestibular system in patients with chronic subjective dizziness: An fMRI study using sound-evoked vestibular stimulation

    Directory of Open Access Journals (Sweden)

    Iole eIndovina

    2015-12-01

    Full Text Available Chronic subjective dizziness (CSD is a common vestibular disorder characterized by persistent non-vertiginous dizziness, unsteadiness, and heightened sensitivity to motion stimuli that may last for months to years after events that cause acute vestibular symptoms or disrupt balance. CSD is not associated with abnormalities of basic vestibular or oculomotor reflexes. Rather, it is thought to arise from persistent use of high-threat postural control strategies and greater reliance on visual cues for spatial orientation (i.e., visual dependence, long after triggering events resolve. Anxiety-related personality traits confer vulnerability to CSD. Anomalous interactions between the central vestibular system and neural structures related to anxiety may sustain it. Vestibular- and anxiety-related processes overlap in the brain, particularly in the insula and hippocampus. Alterations in activity and connectivity in these brain regions in response to vestibular stimuli may be the neural basis of CSD.We examined this hypothesis by comparing brain activity from 18 patients with CSD and 18 healthy controls measured by functional magnetic resonance imaging during loud short tone bursts, which are auditory stimuli that evoke robust vestibular responses. Relative to controls, patients with CSD showed reduced activations to sound-evoked vestibular stimulation in the parieto-insular vestibular cortex (PIVC including the posterior insula, and in the anterior insula, inferior frontal gyrus, hippocampus, and anterior cingulate cortex. Patients with CSD also showed altered connectivity between the anterior insula and PIVC, anterior insula and middle occipital cortex, hippocampus and PIVC, and anterior cingulate cortex and PIVC.We conclude that reduced activation in PIVC, hippocampus, anterior insula, inferior frontal gyrus, and anterior cingulate cortex, as well as connectivity changes among these regions, may be linked to long-term vestibular symptoms in patients

  6. Pharmacology of the vestibular system.

    Science.gov (United States)

    Smith, P F

    2000-02-01

    In the past year significant advances have been made in our understanding of the neurochemistry and neuropharmacology of the peripheral and central vestibular systems. The recognition of the central importance of excitatory amino acids and their receptors at the level of the hair cells, vestibular nerve and vestibular nucleus has progressed further, and the role of nitric oxide in relation to activation of the N-methyl-D-aspartate receptor subtype is becoming increasingly clear. Increasing evidence suggests that excessive N-methyl-D-aspartate receptor activation and nitric oxide production after exposure to aminoglycoside antibiotics is a critical part of hair cell death, and new pharmacological strategies for preventing aminoglycoside ototoxicity are emerging as a result. Conversely, the use of aminoglycosides to lesion the peripheral vestibular system in the treatment of Meniere's disease has been studied intensively. In the vestibular nucleus, new studies suggest the importance of opioid, nociceptin and glucocorticoid receptors in the control of vestibular reflex function. Finally, the mechanisms of action and optimal use of antihistamines in the treatment of vestibular disorders has also received a great deal of attention.

  7. Análise funcional da laringe pós-cordectomia, reconstruída com retalho de prega vestibular Functional analysis of post-cordectomy larynx reconstructed with vestibular fold flap

    Directory of Open Access Journals (Sweden)

    Hilton Ricz

    2004-12-01

    édio de 1,11% e shimmer de 7,04%. Pela escala GRBAS, um paciente apresentou voz normal e 4 tiveram disfonia discreta. CONCLUSÕES: A reconstrução laríngea pós-cordectomia realizada com o retalho da prega vestibular tornou possível emissão de voz normal (freqüência fundamental 205 Hz, jitter 0,13%, shimmer 1,16%, proporcionando coaptação completa em 30% dos casos, fonte sonora vibrátil na região glótica em 70% e participação do retalho como estrutura vibrátil em 90%, além de preservar as funções laríngeas de respiração e proteção das vias aéreas durante a deglutição.Several reports of techniques for larynx reconstruction after partial vertical laryngectomy are available in the literature, some of them using structures of the larynx itself such as the vestibular fold, but few have emphasized analysis of laryngeal function after reconstruction. Thus, the objective of the present study was to assess laryngeal function in patients submitted to total or complete cordectomy (type IV followed by reconstruction with vestibular fold flap. STUDY DESIGN: Cohort transversal. MATERIAL AND METHODS: Ten patients, nine males and one female aged 45 to 75 years (mean age: 64.5 years, with glottis carcinomas treated by total or complete cordectomy (type IV and reconstructed with vestibular fold flap were submitted to videolaryngostroboscopy for assessment of laryngeal permeability, flap positioning, laryngeal closure, arytenoid movement, characteristics of speech sound source (vibrating or frictional and, when the source was vibrating, location and structures of the sound source. Voice quality was evaluated by perceptual acoustic assessment and by objective computer analysis. The function of lower airway protection during swallowing was analyzed by endoscopic evaluation of swallowing. RESULTS: There was no need to maintain tracheostomy during the late postoperative period since the reconstructed laryngeal lumen remained pervious. The function of airway protection

  8. Vestibular Stimulation for Stress Management in Students.

    Science.gov (United States)

    Kumar, Sai Sailesh; Rajagopalan, Archana; Mukkadan, Joseph Kurien

    2016-02-01

    Although several methods are developed to alleviate stress among college students, logistic limitations in adopting them have limited their utility. Hence, we aimed to test a very practical approach to alleviate stress among college students by achieving vestibular stimulation using swings. In this study 60 male and female participants were randomly assigned into vestibular stimulation or control groups. Depression, anxiety, stress scores, sleep quality, heart rate, blood pressure, Autonomic functions, respiratory, haematological, cognitive function, Quality of life were recorded before and after 1(st), 7(th), 14(th), 21(st), 28(th) days of vestibular stimulation. STAI S and STAI T scores were significantly improved on day 28(th) following vestibular stimulation. Diastolic and mean arterial blood pressure were significantly decreased and remained within normal limits in vestibular group on day 28(th) following vestibular stimulation. Postural fall in blood pressure was significantly improved on day 14 onwards, following vestibular stimulation. Respiratory rate was significantly improved on day 7 onwards, following vestibular stimulation. PSQI sleep disturbance, PSQI sleep latency, PSQI total score and bleeding time was significantly improved following vestibular stimulation. Our study supports the adoption of vestibular stimulation for stress management. Hence, placement of swings in college campuses must be considered, which may be a simple approach to alleviate stress among college students.

  9. Prosthetic implantation of the human vestibular system.

    Science.gov (United States)

    Golub, Justin S; Ling, Leo; Nie, Kaibao; Nowack, Amy; Shepherd, Sarah J; Bierer, Steven M; Jameyson, Elyse; Kaneko, Chris R S; Phillips, James O; Rubinstein, Jay T

    2014-01-01

    A functional vestibular prosthesis can be implanted in human such that electrical stimulation of each semicircular canal produces canal-specific eye movements while preserving vestibular and auditory function. A number of vestibular disorders could be treated with prosthetic stimulation of the vestibular end organs. We have previously demonstrated in rhesus monkeys that a vestibular neurostimulator, based on the Nucleus Freedom cochlear implant, can produce canal-specific electrically evoked eye movements while preserving auditory and vestibular function. An investigational device exemption has been obtained from the FDA to study the feasibility of treating uncontrolled Ménière's disease with the device. The UW/Nucleus vestibular implant was implanted in the perilymphatic space adjacent to the three semicircular canal ampullae of a human subject with uncontrolled Ménière's disease. Preoperative and postoperative vestibular and auditory function was assessed. Electrically evoked eye movements were measured at 2 time points postoperatively. Implantation of all semicircular canals was technically feasible. Horizontal canal and auditory function were largely, but not totally, lost. Electrode stimulation in 2 of 3 canals resulted in canal-appropriate eye movements. Over time, stimulation thresholds increased. Prosthetic implantation of the semicircular canals in humans is technically feasible. Electrical stimulation resulted in canal-specific eye movements, although thresholds increased over time. Preservation of native auditory and vestibular function, previously observed in animals, was not demonstrated in a single subject with advanced Ménière's disease.

  10. Extending the Functional Cerebral Systems Theory of Emotion to the Vestibular Modality: A Systematic and Integrative Approach

    Science.gov (United States)

    Carmona, Joseph E.; Holland, Alissa K.; Harrison, David W.

    2009-01-01

    Throughout history, vestibular and emotional dysregulation have often manifested together in clinical settings, with little consideration that they may have a common basis. Regarding vestibular mechanisms, the role of brainstem and cerebellar structures has been emphasized in the neurological literature, whereas emotion processing in the cerebral…

  11. Reviewing the Role of the Efferent Vestibular System in Motor and Vestibular Circuits

    Directory of Open Access Journals (Sweden)

    Miranda A. Mathews

    2017-08-01

    Full Text Available Efferent circuits within the nervous system carry nerve impulses from the central nervous system to sensory end organs. Vestibular efferents originate in the brainstem and terminate on hair cells and primary afferent fibers in the semicircular canals and otolith organs within the inner ear. The function of this efferent vestibular system (EVS in vestibular and motor coordination though, has proven difficult to determine, and remains under debate. We consider current literature that implicate corollary discharge from the spinal cord through the efferent vestibular nucleus (EVN, and hint at a potential role in overall vestibular plasticity and compensation. Hypotheses range from differentiating between passive and active movements at the level of vestibular afferents, to EVS activation under specific behavioral and environmental contexts such as arousal, predation, and locomotion. In this review, we summarize current knowledge of EVS circuitry, its effects on vestibular hair cell and primary afferent activity, and discuss its potential functional roles.

  12. Reviewing the Role of the Efferent Vestibular System in Motor and Vestibular Circuits.

    Science.gov (United States)

    Mathews, Miranda A; Camp, Aaron J; Murray, Andrew J

    2017-01-01

    Efferent circuits within the nervous system carry nerve impulses from the central nervous system to sensory end organs. Vestibular efferents originate in the brainstem and terminate on hair cells and primary afferent fibers in the semicircular canals and otolith organs within the inner ear. The function of this efferent vestibular system (EVS) in vestibular and motor coordination though, has proven difficult to determine, and remains under debate. We consider current literature that implicate corollary discharge from the spinal cord through the efferent vestibular nucleus (EVN), and hint at a potential role in overall vestibular plasticity and compensation. Hypotheses range from differentiating between passive and active movements at the level of vestibular afferents, to EVS activation under specific behavioral and environmental contexts such as arousal, predation, and locomotion. In this review, we summarize current knowledge of EVS circuitry, its effects on vestibular hair cell and primary afferent activity, and discuss its potential functional roles.

  13. Vestibular Contributions to Human Memory

    OpenAIRE

    Smith, Laura; N/A,

    2017-01-01

    The vestibular system is an ancient structure which supports the detection and control of self-motion. The pervasiveness of this sensory system is evidenced by the diversity of its anatomical projections and the profound impact it has on a range of higher level functions, particularly spatial memory. The aim of this thesis was to better characterise the association between the vestibular system and human memory; while many studies have explored this association from a biological perspective f...

  14. Cognitive deficits in patients with a chronic vestibular failure.

    Science.gov (United States)

    Popp, Pauline; Wulff, Melanie; Finke, Kathrin; Rühl, Maxine; Brandt, Thomas; Dieterich, Marianne

    2017-03-01

    Behavioral studies in rodents and humans have demonstrated deficits of spatial memory and orientation in bilateral vestibular failure (BVF). Our aim was to explore the functional consequences of chronic vestibular failure on different cognitive domains including spatial as well as non-spatial cognitive abilities. Sixteen patients with a unilateral vestibular failure (UVF), 18 patients with a BVF, and 17 healthy controls (HC) participated in the study. To assess the cognitive domains of short-term memory, executive function, processing speed and visuospatial abilities the following tests were used: Theory of Visual Attention (TVA), TAP Alertness and Visual Scanning, the Stroop Color-Word, and the Corsi Block Tapping Test. The cognitive scores were correlated with the degree of vestibular dysfunction and the duration of the disease, respectively. Groups did not differ significantly in age, sex, or handedness. BVF patients were significantly impaired in all of the examined cognitive domains but not in all tests of the particular domain, whereas UVF patients exhibited significant impairments in their visuospatial abilities and in one of the two processing speed tasks when compared independently with HC. The degree of vestibular dysfunction significantly correlated with some of the cognitive scores. Neither the side of the lesion nor the duration of disease influenced cognitive performance. The results demonstrate that vestibular failure can lead to cognitive impairments beyond the spatial navigation deficits described earlier. These cognitive impairments are more significant in BVF patients, suggesting that the input from one labyrinth which is distributed into bilateral vestibular circuits is sufficient to maintain most of the cognitive functions. These results raise the question whether BVF patients may profit from specific cognitive training in addition to physiotherapy.

  15. The Effect of Vestibular Rehabilitation Therapy Program on Sensory Organization of Deaf Children With Bilateral Vestibular Dysfunction

    Directory of Open Access Journals (Sweden)

    Amir Abbas Ebrahimi

    2018-01-01

    Full Text Available The purpose of this study was to determine the effect of vestibular rehabilitation therapy program on the sensory organization of deaf children with bilateral vestibular dysfunction. This cross-sectional and analytic study was conducted on 24 students between the age of 7 and 12 years (6 girls and 18 boys with the profound sensorineural hearing loss (PTA>90 dB. They were assessed through the balance subtest in Bruininks-Oseretsky test of motor proficiency (BOTMP. For children which the total score of the balance subtest was 3 standard deviation lower than their peers with typical development, vestibular function testing was completed pre-intervention. Posturography Sensory organization testing (SOT was completed pre- and post-intervention with SPS (Synapsys, Marseille, France. Children with bilateral vestibular impairment were randomly assigned to either the exercise or control group. Exercise intervention consisted of compensatory training, emphasizing enhancement of visual and somatosensory function, and balance training. The exercise group entered in vestibular rehabilitation therapy program for 8 weeks. The children initially participating in the control group were provided the exercise intervention following the post-test. Based on the results there was significant difference in condition 5 and 6, areas of limits of stability (LOS, vestibular ratio and global score in posturography at the end of the intervention, but there was no significant difference in the control group in posturography (P<0.05. The results indicated that testing of vestibular, and postural control function, as well as intervention for deficiencies identified, should be included in deaf children rehabilitation program.

  16. The Effect of Vestibular Rehabilitation Therapy Program on Sensory Organization of Deaf Children With Bilateral Vestibular Dysfunction.

    Science.gov (United States)

    Ebrahimi, Amir Abbas; Jamshidi, Ali Ashraf; Movallali, Guita; Rahgozar, Mehdi; Haghgoo, Hojjat Allah

    2017-11-01

    The purpose of this study was to determine the effect of vestibular rehabilitation therapy program on the sensory organization of deaf children with bilateral vestibular dysfunction. This cross-sectional and analytic study was conducted on 24 students between the age of 7 and 12 years (6 girls and 18 boys) with the profound sensorineural hearing loss (PTA>90 dB). They were assessed through the balance subtest in Bruininks-Oseretsky test of motor proficiency (BOTMP). For children which the total score of the balance subtest was 3 standard deviation lower than their peers with typical development, vestibular function testing was completed pre-intervention. Posturography Sensory organization testing (SOT) was completed pre- and post-intervention with SPS (Synapsys, Marseille, France). Children with bilateral vestibular impairment were randomly assigned to either the exercise or control group. Exercise intervention consisted of compensatory training, emphasizing enhancement of visual and somatosensory function, and balance training. The exercise group entered in vestibular rehabilitation therapy program for 8 weeks. The children initially participating in the control group were provided the exercise intervention following the post-test. Based on the results there was significant difference in condition 5 and 6, areas of limits of stability (LOS), vestibular ratio and global score in posturography at the end of the intervention, but there was no significant difference in the control group in posturography (P<0.05). The results indicated that testing of vestibular, and postural control function, as well as intervention for deficiencies identified, should be included in deaf children rehabilitation program.

  17. Neuropharmacology of vestibular system disorders.

    Science.gov (United States)

    Soto, Enrique; Vega, Rosario

    2010-03-01

    This work reviews the neuropharmacology of the vestibular system, with an emphasis on the mechanism of action of drugs used in the treatment of vestibular disorders. Otolaryngologists are confronted with a rapidly changing field in which advances in the knowledge of ionic channel function and synaptic transmission mechanisms have led to the development of new scientific models for the understanding of vestibular dysfunction and its management. In particular, there have been recent advances in our knowledge of the fundamental mechanisms of vestibular system function and drug mechanisms of action. In this work, drugs acting on vestibular system have been grouped into two main categories according to their primary mechanisms of action: those with effects on neurotransmitters and neuromodulator receptors and those that act on voltage-gated ion channels. Particular attention is given in this review to drugs that may provide additional insight into the pathophysiology of vestibular diseases. A critical review of the pharmacology and highlights of the major advances are discussed in each case.

  18. Gene therapy restores auditory and vestibular function in a mouse model of Usher syndrome type 1c.

    Science.gov (United States)

    Pan, Bifeng; Askew, Charles; Galvin, Alice; Heman-Ackah, Selena; Asai, Yukako; Indzhykulian, Artur A; Jodelka, Francine M; Hastings, Michelle L; Lentz, Jennifer J; Vandenberghe, Luk H; Holt, Jeffrey R; Géléoc, Gwenaëlle S

    2017-03-01

    Because there are currently no biological treatments for hearing loss, we sought to advance gene therapy approaches to treat genetic deafness. We focused on Usher syndrome, a devastating genetic disorder that causes blindness, balance disorders and profound deafness, and studied a knock-in mouse model, Ush1c c.216G>A, for Usher syndrome type IC (USH1C). As restoration of complex auditory and balance function is likely to require gene delivery systems that target auditory and vestibular sensory cells with high efficiency, we delivered wild-type Ush1c into the inner ear of Ush1c c.216G>A mice using a synthetic adeno-associated viral vector, Anc80L65, shown to transduce 80-90% of sensory hair cells. We demonstrate recovery of gene and protein expression, restoration of sensory cell function, rescue of complex auditory function and recovery of hearing and balance behavior to near wild-type levels. The data represent unprecedented recovery of inner ear function and suggest that biological therapies to treat deafness may be suitable for translation to humans with genetic inner ear disorders.

  19. Vestibular insights into cognition and psychiatry.

    Science.gov (United States)

    Gurvich, Caroline; Maller, Jerome J; Lithgow, Brian; Haghgooie, Saman; Kulkarni, Jayashri

    2013-11-06

    The vestibular system has traditionally been thought of as a balance apparatus; however, accumulating research suggests an association between vestibular function and psychiatric and cognitive symptoms, even when balance is measurably unaffected. There are several brain regions that are implicated in both vestibular pathways and psychiatric disorders. The present review examines the anatomical associations between the vestibular system and various psychiatric disorders. Despite the lack of direct evidence for vestibular pathology in the key psychiatric disorders selected for this review, there is a substantial body of literature implicating the vestibular system in each of the selected psychiatric disorders. The second part of this review provides complimentary evidence showing the link between vestibular dysfunction and vestibular stimulation upon cognitive and psychiatric symptoms. In summary, emerging research suggests the vestibular system can be considered a potential window for exploring brain function beyond that of maintenance of balance, and into areas of cognitive, affective and psychiatric symptomology. Given the paucity of biological and diagnostic markers in psychiatry, novel avenues to explore brain function in psychiatric disorders are of particular interest and warrant further exploration. © 2013 Elsevier B.V. All rights reserved.

  20. Physical therapy for persons with vestibular disorders.

    Science.gov (United States)

    Whitney, Susan L; Alghwiri, Alia; Alghadir, Ahmad

    2015-02-01

    Persons with vestibular disorders experience symptoms of dizziness and balance dysfunction, resulting in falls, as well as impairments of daily life. Various interventions provided by physical therapists have been shown to decrease dizziness and improve postural control. In the present review, we will focus on the role of physical therapy in the management of vestibular symptoms in patients with peripheral and central vestibular disorders. Persons with both acute and chronic central and peripheral vestibular disorders improve with vestibular rehabilitation. New interventions during the past 5 years have been designed to enhance recovery from problems with balance and dizziness. Examples include the use of virtual reality, vibrotactile feedback, optokinetic flow, YouTube videos, and innovative methods to change the gain of the vestibulo-ocular reflex (VOR). Patients with central and peripheral vestibular disorders benefit from physical therapy interventions. Advances in physical therapy interventions include new methods to stimulate adaptation of the VOR and the vestibulospinal systems.

  1. Epidemiology and natural history of vestibular schwannomas

    DEFF Research Database (Denmark)

    Stangerup, Sven-Eric; Caye-Thomasen, Per

    2012-01-01

    This article describes various epidemiologic trends for vestibular schwannomas over the last 35 years, including a brief note on terminology. Additionally, it provides information on the natural history of tumor growth and hearing level following the diagnosis of a vestibular schwannoma. A treatm......This article describes various epidemiologic trends for vestibular schwannomas over the last 35 years, including a brief note on terminology. Additionally, it provides information on the natural history of tumor growth and hearing level following the diagnosis of a vestibular schwannoma....... A treatment strategy based on the natural history of tumor growth and hearing also is discussed....

  2. The dizzy patient: don't forget disorders of the central vestibular system.

    Science.gov (United States)

    Brandt, Thomas; Dieterich, Marianne

    2017-06-01

    Vertigo and dizziness are among the most common complaints in neurology clinics, and they account for about 13% of the patients entering emergency units. In this Review, we focus on central vestibular disorders, which are mostly attributable to acute unilateral lesions of the bilateral vestibular circuitry in the brain. In a tertiary interdisciplinary outpatient dizziness unit, central vestibular disorders, including vestibular migraine, comprise about 25% of the established diagnoses. The signs and symptoms of these disorders can mimic those of peripheral vestibular disorders with sustained rotational vertigo. Bedside examinations, such as the head impulse test and ocular motor testing to determine spontaneous and gaze-evoked nystagmus or skew deviation, reliably differentiate central from peripheral syndromes. We also consider disorders of 'higher vestibular functions', which involve more than one sensory modality as well as cognitive domains (for example, orientation, spatial memory and navigation). These disorders include hemispatial neglect, the room tilt illusion, pusher syndrome, and impairment of spatial memory and navigation associated with hippocampal atrophy in cases of peripheral bilateral vestibular loss.

  3. Balance Training Enhances Vestibular Function and Reduces Overactive Proprioceptive Feedback in Elderly

    Science.gov (United States)

    Wiesmeier, Isabella K.; Dalin, Daniela; Wehrle, Anja; Granacher, Urs; Muehlbauer, Thomas; Dietterle, Joerg; Weiller, Cornelius; Gollhofer, Albert; Maurer, Christoph

    2017-01-01

    Objectives: Postural control in elderly people is impaired by degradations of sensory, motor, and higher-level adaptive mechanisms. Here, we characterize the effects of a progressive balance training program on these postural control impairments using a brain network model based on system identification techniques. Methods and Material: We analyzed postural control of 35 healthy elderly subjects and compared findings to data from 35 healthy young volunteers. Eighteen elderly subjects performed a 10 week balance training conducted twice per week. Balance training was carried out in static and dynamic movement states, on support surfaces with different elastic compliances, under different visual conditions and motor tasks. Postural control was characterized by spontaneous sway and postural reactions to pseudorandom anterior-posterior tilts of the support surface. Data were interpreted using a parameter identification procedure based on a brain network model. Results: With balance training, the elderly subjects significantly reduced their overly large postural reactions and approximated those of younger subjects. Less significant differences between elderly and young subjects' postural control, namely larger spontaneous sway amplitudes, velocities, and frequencies, larger overall time delays and a weaker motor feedback compared to young subjects were not significantly affected by the balance training. Conclusion: Balance training reduced overactive proprioceptive feedback and restored vestibular orientation in elderly. Based on the assumption of a linear deterioration of postural control across the life span, the training effect can be extrapolated as a juvenescence of 10 years. This study points to a considerable benefit of a continuous balance training in elderly, even without any sensorimotor deficits. PMID:28848430

  4. Balance Training Enhances Vestibular Function and Reduces Overactive Proprioceptive Feedback in Elderly.

    Science.gov (United States)

    Wiesmeier, Isabella K; Dalin, Daniela; Wehrle, Anja; Granacher, Urs; Muehlbauer, Thomas; Dietterle, Joerg; Weiller, Cornelius; Gollhofer, Albert; Maurer, Christoph

    2017-01-01

    Objectives: Postural control in elderly people is impaired by degradations of sensory, motor, and higher-level adaptive mechanisms. Here, we characterize the effects of a progressive balance training program on these postural control impairments using a brain network model based on system identification techniques. Methods and Material: We analyzed postural control of 35 healthy elderly subjects and compared findings to data from 35 healthy young volunteers. Eighteen elderly subjects performed a 10 week balance training conducted twice per week. Balance training was carried out in static and dynamic movement states, on support surfaces with different elastic compliances, under different visual conditions and motor tasks. Postural control was characterized by spontaneous sway and postural reactions to pseudorandom anterior-posterior tilts of the support surface. Data were interpreted using a parameter identification procedure based on a brain network model. Results: With balance training, the elderly subjects significantly reduced their overly large postural reactions and approximated those of younger subjects. Less significant differences between elderly and young subjects' postural control, namely larger spontaneous sway amplitudes, velocities, and frequencies, larger overall time delays and a weaker motor feedback compared to young subjects were not significantly affected by the balance training. Conclusion: Balance training reduced overactive proprioceptive feedback and restored vestibular orientation in elderly. Based on the assumption of a linear deterioration of postural control across the life span, the training effect can be extrapolated as a juvenescence of 10 years. This study points to a considerable benefit of a continuous balance training in elderly, even without any sensorimotor deficits.

  5. Balance Training Enhances Vestibular Function and Reduces Overactive Proprioceptive Feedback in Elderly

    Directory of Open Access Journals (Sweden)

    Isabella K. Wiesmeier

    2017-08-01

    Full Text Available Objectives: Postural control in elderly people is impaired by degradations of sensory, motor, and higher-level adaptive mechanisms. Here, we characterize the effects of a progressive balance training program on these postural control impairments using a brain network model based on system identification techniques.Methods and Material: We analyzed postural control of 35 healthy elderly subjects and compared findings to data from 35 healthy young volunteers. Eighteen elderly subjects performed a 10 week balance training conducted twice per week. Balance training was carried out in static and dynamic movement states, on support surfaces with different elastic compliances, under different visual conditions and motor tasks. Postural control was characterized by spontaneous sway and postural reactions to pseudorandom anterior-posterior tilts of the support surface. Data were interpreted using a parameter identification procedure based on a brain network model.Results: With balance training, the elderly subjects significantly reduced their overly large postural reactions and approximated those of younger subjects. Less significant differences between elderly and young subjects' postural control, namely larger spontaneous sway amplitudes, velocities, and frequencies, larger overall time delays and a weaker motor feedback compared to young subjects were not significantly affected by the balance training.Conclusion: Balance training reduced overactive proprioceptive feedback and restored vestibular orientation in elderly. Based on the assumption of a linear deterioration of postural control across the life span, the training effect can be extrapolated as a juvenescence of 10 years. This study points to a considerable benefit of a continuous balance training in elderly, even without any sensorimotor deficits.

  6. Peripheral Vestibular System Disease in Vestibular Schwannomas

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Hansen, Søren; Caye-Thomasen, Per

    2015-01-01

    that this may be caused by both cochlear and retrocochlear mechanisms. Multiple mechanisms may also be at play in the case of dizziness, which may broaden perspectives of therapeutic approach. This study presents a systematic and detailed assessment of vestibular histopathology in temporal bones from patients...... with VS. METHODS: Retrospective analysis of vestibular system histopathology in temporal bones from 17 patients with unilateral VS. The material was obtained from The Copenhagen Temporal Bone Collection. RESULTS: Vestibular schwannomas were associated with atrophy of the vestibular ganglion, loss of fiber...... density of the peripheral vestibular nerve branches, and atrophy of the neuroepithelium of the vestibular end organs. In cases with small tumors, peripheral disease occurred only in the tissue structures innervated by the specific nerve from which the tumor originated. CONCLUSION: Vestibular schwannomas...

  7. Vestibular activation, smooth pursuit tracking, and psychosis.

    Science.gov (United States)

    Jones, A M; Pivik, R T

    1985-04-01

    Pursuit tracking and vestibular activation procedures were combined in an investigation to determine if smooth pursuit tracking deficits could be related to abnormalities of visual-vestibular interaction in psychiatric patients. In actively psychotic patients, but not in comparison groups of schizophrenic outpatients with remitted symptomatology or normal controls, a significant failure of visual fixation to suppress caloric nystagmus was related to a higher incidence of disordered tracking during both baseline and postirrigation conditions. Other vestibular irregularities including dysrhythmia and reduced fast phase velocity were observed in these same patients. The results are supportive of a central deficit in visual-vestibular interaction that may contribute to pursuit tracking deficits in psychosis.

  8. A review of the interrelationship between vestibular dysfunction ...

    African Journals Online (AJOL)

    problems and dyslexia were also associated with dysfunction of the vestibular system. Different tests evaluating vestibular loss were identified of which some can be used successfully by practitionars. Various programmes and activities were identified to successfully rehabilitate vestibular function. For better understanding ...

  9. Correlation between vestibular and autonomous function after 6 months of spaceflight: Data of the SPIN and GAZE-SPIN experiments.

    Science.gov (United States)

    Wuyts, Floris; Clement, Gilles; Naumov, Ivan; Kornilova, Ludmila; Glukhikh, Dmitriy; Hallgren, Emma; MacDougall, Hamish; Migeotte, Pierre-Francois; Delière, Quentin; Weerts, Aurelie; Moore, Steven; Diedrich, Andre

    In 13 cosmonauts, the vestibulo-autonomic reflex was investigated before and after 6 months duration spaceflight. Cosmonauts were rotated on the mini-centrifuge VVIS, which is installed in Star City. Initially, this mini-centrifuge flew on board of the Neurolab mission (STS-90), and served to generate intermittent artificial gravity during that mission, with apparent very positive effects on the preservation of the orthostatic tolerance upon return to earth in the 4 crew members that were subjected to the rotations in space. The current experiments SPIN and GAZE-SPIN are control experiments to test the hypothesis that intermittent artificial gravity in space can serve as a counter measure against several deleterious effects of microgravity. Additionally, the effect of microgravity on the gaze holding system is studied as well. Cosmonauts from a long duration stay in the International Space Station were tested on the VVIS (1 g centripetal interaural acceleration; consecutive right-ear-out anti-clockwise and left-ear-out clockwise measurement) on 5 different days. Two measurements were scheduled about one month and a half prior to launch and the remaining three immediately after their return from space (typically on R+2, R+4, R+9; R = return day from space). The ocular counter roll (OCR) as a measure of otolith function was measured on before, during and after the rotation in the mini centrifuge, using infrared video goggles. The perception of verticality was monitored using an ultrasound system. Gaze holding was tested before, during and after rotation. After the centrifugation part, the crew was installed on a tilt table, and instrumented with several cardiovascular recording equipment (ECG, continuous blood pressure monitoring, respiratory monitoring), as well as with impedance measurement devices to investigate fluid redistribution throughout the operational tilt test. To measure heart rate variability parameters, imposed breathing periods were included in the

  10. Exhibition of Stochastic Resonance in Vestibular Perception

    Science.gov (United States)

    Galvan-Garza, R. C.; Clark, T. K.; Merfeld, D. M.; Bloomberg, J. J.; Oman, C. M.; Mulavara, A. P.

    2016-01-01

    Astronauts experience sensorimotor changes during spaceflight, particularly during G-transitions. Post flight sensorimotor changes include spatial disorientation, along with postural and gait instability that may degrade operational capabilities of the astronauts and endanger the crew. A sensorimotor countermeasure that mitigates these effects would improve crewmember safety and decrease risk. The goal of this research is to investigate the potential use of stochastic vestibular stimulation (SVS) as a technology to improve sensorimotor function. We hypothesize that low levels of SVS will improve sensorimotor perception through the phenomenon of stochastic resonance (SR), when the response of a nonlinear system to a weak input signal is enhanced by the application of a particular nonzero level of noise. This study aims to advance the development of SVS as a potential countermeasure by 1) demonstrating the exhibition of stochastic resonance in vestibular perception, a vital component of sensorimotor function, 2) investigating the repeatability of SR exhibition, and 3) determining the relative contribution of the semicircular canals (SCC) and otolith (OTO) organs to vestibular perceptual SR. A constant current stimulator was used to deliver bilateral bipolar SVS via electrodes placed on each of the mastoid processes, as previously done. Vestibular perceptual motion recognition thresholds were measured using a 6-degree of freedom MOOG platform and a 150 trial 3-down/1-up staircase procedure. In the first test session, we measured vestibular perceptual thresholds in upright roll-tilt at 0.2 Hz (SCC+OTO) with SVS ranging from 0-700 µA. In a second test session a week later, we re-measured roll-tilt thresholds with 0, optimal (from test session 1), and 1500 µA SVS levels. A subset of these subjects, plus naive subjects, participated in two additional test sessions in which we measured thresholds in supine roll-rotation at 0.2 Hz (SCC) and upright y-translation at 1 Hz

  11. Isolated vestibular nuclear infarction: report of two cases and review of the literature.

    Science.gov (United States)

    Kim, Hyo-Jung; Lee, Seung-Han; Park, Jae Han; Choi, Jung-Yoon; Kim, Ji-Soo

    2014-01-01

    Cerebral infarction presenting with isolated vertigo remains a diagnostic challenge. To define the clinical characteristics of unilateral infarctions restricted to the vestibular nuclei, two patients with isolated unilateral vestibular nuclear infarction had bedside and laboratory evaluation of the ocular motor and vestibular function, including video-oculography, bithermal caloric irrigation, the head impulse test (HIT) using magnetic scleral coils, and cervical and ocular vestibular-evoked myogenic potentials (VEMPs). We also reviewed the literature on isolated vertigo from lesions restricted to the vestibular nuclei, and analyzed the clinical features of seven additional patients. Both patients showed spontaneous torsional-horizontal nystagmus that beat away from the lesion side, and direction-changing gaze-evoked nystagmus. Recording of HIT using a magnetic search coil system documented decreased gains of the vestibular-ocular reflex for the horizontal and posterior semicircular canals on both sides, but more for the ipsilesional canals. Bithermal caloric tests showed ipsilesional canal paresis in both patients. Cervical and ocular VEMPs showed decreased or absent responses during stimulation of the ipsilesional ear. Initial MRIs including diffusion-weighted images were normal or equivocal, but follow-up imaging disclosed a circumscribed acute infarction in the area of the vestibular nuclei. Infarctions restricted to the vestibular nuclei may present with isolated vertigo with features of both peripheral and central vestibulopathies. Central signs should be sought even in patients with spontaneous horizontal-torsional nystagmus and positive HIT. In patients with combined peripheral and central vestibulopathy, a vestibular nuclear lesion should be considered especially when hearing is preserved.

  12. Local gene therapy durably restores vestibular function in a mouse model of Usher syndrome type 1G.

    Science.gov (United States)

    Emptoz, Alice; Michel, Vincent; Lelli, Andrea; Akil, Omar; Boutet de Monvel, Jacques; Lahlou, Ghizlene; Meyer, Anaïs; Dupont, Typhaine; Nouaille, Sylvie; Ey, Elody; Franca de Barros, Filipa; Beraneck, Mathieu; Dulon, Didier; Hardelin, Jean-Pierre; Lustig, Lawrence; Avan, Paul; Petit, Christine; Safieddine, Saaid

    2017-09-05

    Our understanding of the mechanisms underlying inherited forms of inner ear deficits has considerably improved during the past 20 y, but we are still far from curative treatments. We investigated gene replacement as a strategy for restoring inner ear functions in a mouse model of Usher syndrome type 1G, characterized by congenital profound deafness and balance disorders. These mice lack the scaffold protein sans, which is involved both in the morphogenesis of the stereociliary bundle, the sensory antenna of inner ear hair cells, and in the mechanoelectrical transduction process. We show that a single delivery of the sans cDNA by the adenoassociated virus 8 to the inner ear of newborn mutant mice reestablishes the expression and targeting of the protein to the tips of stereocilia. The therapeutic gene restores the architecture and mechanosensitivity of stereociliary bundles, improves hearing thresholds, and durably rescues these mice from the balance defects. Our results open up new perspectives for efficient gene therapy of cochlear and vestibular disorders by showing that even severe dysmorphogenesis of stereociliary bundles can be corrected.

  13. Local gene therapy durably restores vestibular function in a mouse model of Usher syndrome type 1G

    Science.gov (United States)

    Emptoz, Alice; Michel, Vincent; Lelli, Andrea; Akil, Omar; Boutet de Monvel, Jacques; Lahlou, Ghizlene; Meyer, Anaïs; Dupont, Typhaine; Nouaille, Sylvie; Ey, Elody; Franca de Barros, Filipa; Beraneck, Mathieu; Dulon, Didier; Hardelin, Jean-Pierre; Lustig, Lawrence; Avan, Paul; Petit, Christine; Safieddine, Saaid

    2017-01-01

    Our understanding of the mechanisms underlying inherited forms of inner ear deficits has considerably improved during the past 20 y, but we are still far from curative treatments. We investigated gene replacement as a strategy for restoring inner ear functions in a mouse model of Usher syndrome type 1G, characterized by congenital profound deafness and balance disorders. These mice lack the scaffold protein sans, which is involved both in the morphogenesis of the stereociliary bundle, the sensory antenna of inner ear hair cells, and in the mechanoelectrical transduction process. We show that a single delivery of the sans cDNA by the adenoassociated virus 8 to the inner ear of newborn mutant mice reestablishes the expression and targeting of the protein to the tips of stereocilia. The therapeutic gene restores the architecture and mechanosensitivity of stereociliary bundles, improves hearing thresholds, and durably rescues these mice from the balance defects. Our results open up new perspectives for efficient gene therapy of cochlear and vestibular disorders by showing that even severe dysmorphogenesis of stereociliary bundles can be corrected. PMID:28835534

  14. [Effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in the guinea pig].

    Science.gov (United States)

    Feng, B; Jiang, S; Yang, W; Han, D; Zhang, S

    2001-02-01

    To define the effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in guinea pigs. The animals involved in the study were exposed to 8 Hz infrasound at 135dB SPL for 90 minutes in a reverberant chamber. The sinusoidal pendular test (SPT), auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) were respectively detected pre-exposure and at 0(within 2 hrs), 2 and 5 day after exposure. The ultrastructures of the inner ear were observed by scanning electron microscopy. The slow-phase velocity and the frequency of the vestibular nystagmus elicited by sinusoidal pendular test (SPT) declined slightly following infrasound exposure, but the changes were not significant (P > 0.05). No differences in the ABR thresholds, the latencies and the interval peak latencies of I, III, V waves were found between the normal and the experimental groups, and among experimental groups. The amplitudes of DPOAE at any frequency declined remarkably in all experimental groups. The ultrastructures of the inner ear were damaged to different extent. Infrasound could transiently depress the excitability of the vestibular end-organs, decrease the function of OHC in the organ of Corti and cause damage to the inner ear of guinea pigs.

  15. The long-term consequences of the exposure to increasing gravity levels on the muscular, vestibular and cognitive functions in adult mice.

    Science.gov (United States)

    Bojados, Mickael; Jamon, Marc

    2014-05-01

    Adult male mice C57Bl6/J were exposed to gravity levels between 1G and 4G during three weeks, and the long-term consequences on muscular, vestibular, emotional, and cognitive abilities were evaluated at the functional level to test the hypothesis of a continuum in the response to the increasing gravitational force. In agreement with the hypothesis, the growth of body mass slowed down in relation with the gravity level during the centrifugation, and weight recovery was inversely proportional. On the other hand, the long-term consequences on muscular, vestibular, emotional, and cognitive abilities did not fit the hypothesis of a continuum in the response to the gravity level. The hypergravity acted as endurance training on muscle force until 3G, then became deleterious at 4G. The vestibular reactions were not affected until 4G. Persistent emotional reactions appeared at 3G, and particularly 4G. The mice centrifuged at 3G and 4G showed an impaired spatial learning, probably in relation with the increased level of anxiety, but a greater difficulty was also observed in mice exposed at 2G, suggesting another cause for the impairment of spatial memory. The long-term response to the hypergravity was shown to depend on both the level of gravity and the duration of exposition, with different importance depending on the function considered. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Reviewing the Role of the Efferent Vestibular System in Motor and Vestibular Circuits

    OpenAIRE

    Mathews, Miranda A.; Camp, Aaron J.; Murray, Andrew J.

    2017-01-01

    Efferent circuits within the nervous system carry nerve impulses from the central nervous system to sensory end organs. Vestibular efferents originate in the brainstem and terminate on hair cells and primary afferent fibers in the semicircular canals and otolith organs within the inner ear. The function of this efferent vestibular system (EVS) in vestibular and motor coordination though, has proven difficult to determine, and remains under debate. We consider current literature that implicate...

  17. Presynaptic and postsynaptic ion channel expression in vestibular nuclei neurons after unilateral vestibular deafferentation.

    Science.gov (United States)

    Shao, Mei; Popratiloff, Anastas; Hirsch, June C; Peusner, Kenna D

    2009-01-01

    Vestibular compensation refers to the recovery of function occurring after unilateral vestibular deafferentation, but some patients remain uncompensated. Similarly, more than half of the operated chickens compensate three days after unilateral vestibular ganglionectomy (UVG), but the rest remain uncompensated. This review focuses on the studies performed on the principal cells of the chick tangential nucleus after UVG. The tangential nucleus is a major avian vestibular nucleus whose principal cells are all second-order, vestibular reflex projection neurons participating in the vestibuloocular and vestibulocollic reflexes controlling posture, balance, and eye movements. Using whole-cell patch-clamp approach in brain slice preparations, spontaneous spike firing, ionic conductances, and spontaneous excitatory postsynaptic currents (sEPSCs) are recorded in principal cells from controls and operated chickens three days after UVG. In compensated chickens, the proportion of spontaneous spike firing principal cells and their spike discharge rate are symmetric on the lesion and intact sides, with the rates increased over controls. However, in the uncompensated chickens, the spike discharge rate increases on the lesion side, but not on the intact side, where only silent principal cells are recorded. In all the experimental groups, including controls, silent principal cells are distinguished from spontaneous spiking cells by smaller persistent sodium conductances and higher activation thresholds for the fast sodium channel. In addition, silent principal cells on the intact side of uncompensated chickens have larger dendrotoxin-sensitive potassium conductances, with a higher ratio of immunolabeling for surface/cytoplasmic expression of a dendrotoxin-sensitive, potassium channel subunit, Kv1.1. Finally, in compensated chickens, sEPSC frequency is symmetric bilaterally, but in uncompensated chickens sEPSC frequency increased only on the lesion side, where the expression of Kv1

  18. Relationship of Vertigo and Postural Instability in Patients With Vestibular Schwannoma.

    Science.gov (United States)

    Nam, Gi-Sung; Jung, Chan Min; Kim, Ji Hyung; Son, Eun Jin

    2018-01-09

    Growth of vestibular schwannomas (VS) causes progressive vestibular symptoms and postural instability. Since the tumor grows slowly, compensation of decaying vestibular input may decrease subjective symptoms of dizziness. This study aims to estimate the relationship of subjective vestibular symptoms and objective postural instability in patients with VS. A retrospective review of 18 patients newly diagnosed with VS and with subjective vertigo symptoms was performed. The Results of vestibular function tests including the sensory organization test (SOT) using computerized dynamic posturography, caloric test, and self-report measures of subjective dizziness handicap (Dizziness Handicap Inventory) and visual analogue scale were compared according to the onset of vertigo symptoms. In VS patients, SOT showed decreased equilibrium score for all vestibular function related conditions, condition (C) 5 and 6, and composite (COMP) score. COMP scores were not correlated with visual analogue scale or Dizziness Handicap Inventory scores. Acute onset group included six patients and insidious onset group, 12 patients. Equilibrium scores for C5 and C6, and COMP scores were lower for insidious onset group, but the difference was not statistically significant. Our findings confirmed postural instability is prevalent in VS patients. SOT parameters did not differ significantly between acute onset and insidious onset groups, but increased tumor size and canal weakness were noted in the insidious onset group. Clinicians should consider that postural instability is likely present even in patients who do not complain of acute vertigo, and appropriate counseling should be discussed with the patients.

  19. Ocular Vestibular Evoked Myogenic Potentials

    Directory of Open Access Journals (Sweden)

    Felipe, Lilian

    2014-01-01

    Full Text Available Introduction Diagnostic testing of the vestibular system is an essential component of treating patients with balance dysfunction. Until recently, testing methods primarily evaluated the integrity of the horizontal semicircular canal, which is only a portion of the vestibular system. Recent advances in technology have afforded clinicians the ability to assess otolith function through vestibular evoked myogenic potential (VEMP testing. VEMP testing from the inferior extraocular muscles of the eye has been the subject of interest of recent research. Objective To summarize recent developments in ocular VEMP testing. Results Recent studies suggest that the ocular VEMP is produced by otolith afferents in the superior division of the vestibular nerve. The ocular VEMP is a short latency potential, composed of extraocular myogenic responses activated by sound stimulation and registered by surface electromyography via ipsilateral otolithic and contralateral extraocular muscle activation. The inferior oblique muscle is the most superficial of the six extraocular muscles responsible for eye movement. Therefore, measurement of ocular VEMPs can be performed easily by using surface electrodes on the skin below the eyes contralateral to the stimulated side. Conclusion This new variation of the VEMP procedure may supplement conventional testing in difficult to test populations. It may also be possible to use this technique to evaluate previously inaccessible information on the vestibular system.

  20. An adaptive vestibular rehabilitation technique.

    Science.gov (United States)

    Crane, Benjamin T; Schubert, Michael C

    2017-05-23

    There is a large variation in vestibular rehabilitation (VR) results depending on type of therapy, adherence, and the appropriateness for the patient's level of function. A novel adaptive vestibular rehabilitation (AVR) program was developed and evaluated. Technology and procedure development, and prospective multicenter trial. Those with complete unilateral vestibular hypofunction and symptomatic at least 3 months with a Dizziness Handicap Inventory (DHI) >30 were eligible. Patients were given a device to use with their own computer. They were instructed to use the program daily, with each session lasting about 10 minutes. The task consisted of reporting orientation of the letter C, which appeared when their angular head velocity exceeded a threshold. The letter size and head velocity required were adjusted based on prior performance. Performance on the task was remotely collected by the investigator as well as a weekly DHI score. Four patients aged 31 to 74 years (mean = 51 years) were enrolled in this feasibility study to demonstrate efficacy. Two had treated vestibular schwannomas and two had vestibular neuritis. Starting DHI was 32 to 56 (mean = 42), which was reduced to 0 to 16 (mean = 11.5) after a month of therapy, a clinically and statistically significant (P VR in terms of cost and customization for patient ability and obtained a major improvement in symptoms. This study demonstrated a clinically and statistically significant decrease in symptoms after 4 weeks of therapy. 2b Laryngoscope, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  1. Vestibular, balance, microvascular and white matter neuroimaging characteristics of blast injuries and mild traumatic brain injury: Four case reports.

    Science.gov (United States)

    Gattu, Ramtilak; Akin, Faith W; Cacace, Anthony T; Hall, Courtney D; Murnane, Owen D; Haacke, E Mark

    2016-01-01

    Case reports are presented on four Veterans, aged 29-46 years, who complained of chronic dizziness and/or postural instability following blast exposures. Two of the four individuals were diagnosed with mild traumatic brain injury and three of the four were exposed to multiple blasts. Comprehensive vestibular, balance, gait, audiometry and neuroimaging procedures were used to characterize their injuries. Vestibular assessment included videonystagmography, rotary chair and cervical and ocular vestibular evoked myogenic potentials. Balance and gait testing included the sensory organization test, preferred gait speed and the dynamic gait index. Audiometric studies included pure tone audiometry and middle-ear measurements. Neuroimaging procedures included high resolution structural magnetic resonance imaging, susceptibility-weighted imaging and diffusion-tensor imaging. Based on the neuroimaging and vestibular and balance test results, it was found that all individuals had diffuse axonal injuries and all had one or more micro-hemorrhages or vascular anomalies. Three of the four individuals had abnormal vestibular function, all had abnormally slow walking speeds and two had abnormal gait and balance dysfunction. The use of contemporary neuroimaging studies in conjunction with comprehensive vestibular and balance assessment provided a better understanding of the pathophysiology and pathoanatomy of dizziness following blast exposures than standard vestibular and balance testing alone.

  2. [Vestibular rehabilitation in elderly patients with dizziness].

    Science.gov (United States)

    Zanardini, Francisco Halilla; Zeigelboim, Bianca Simone; Jurkiewicz, Ari Leon; Marques, Jair Mendes; Martins-Bassetto, Jackeline

    2007-01-01

    The aging of the population is a natural process and is manifested by a decline in the functions of several organs. Vestibular rehabilitation (VR) is a therapeutic process that seeks to promote a significant reduction in the symptoms of the labyrinth. To verify the benefits of VR exercises through the application of the Dizziness Handicap Inventory (DHI) questionnaire--Brazilian version--pre and post rehabilitation. Participants of this study were eight elderly patients with dizziness, ages between 63 and 82 years, three male and five female. The following procedures were carried out: medical history, otologic inspection, vestibular evaluation with vectoelectronystagmography (VENG), application of the DHI questionnaire and of the Cawthorne (1944) and Cooksey (1946) VR exercises. Regarding the auditory and vestibular complaints which were referred to in the medical history, the following was observed: presence of tinnitus, hearing loss, postural vertigo and of unbalance. In the evaluation of the vestibular function alterations were observed for all of the participants, mainly in the caloric test, with a prevalence of unilateral and bilateral hypofunction. In the vestibular exam the following was observed: three cases of unilateral peripheral vestibular deficit syndrome, three cases of bilateral peripheral vestibular deficit syndrome, one case of bilateral central vestibular deficit syndrome and one case of irritating bilateral central vestibular syndrome. There was a statistically significant improvement of the following aspects after VR: physical (p=0.00413), functional (p=0.00006) and emotional (p=0.03268). The VR protocol favored the improvement of life quality of the participants and was of assistance in the process of vestibular compensation.

  3. Vestibular implants studied in animal models: clinical and scientific implications.

    Science.gov (United States)

    Lewis, Richard F

    2016-12-01

    Damage to the peripheral vestibular system can result in debilitating postural, perceptual, and visual symptoms. A potential new treatment for this clinical problem is to replace some aspects of peripheral vestibular function with an implant that senses head motion and provides this information to the brain by stimulating branches of the vestibular nerve. In this review I consider animal studies performed at our institution over the past 15 years, which have helped elucidate how the brain processes information provided by a vestibular (semicircular canal) implant and how this information could be used to improve the problems experienced by patients with peripheral vestibular damage. Copyright © 2016 the American Physiological Society.

  4. Molecular epidemiology and functional assessment of novel allelic variants of SLC26A4 in non-syndromic hearing loss patients with enlarged vestibular aqueduct in China.

    Directory of Open Access Journals (Sweden)

    Yongyi Yuan

    Full Text Available Mutations in SLC26A4, which encodes pendrin, are a common cause of deafness. SLC26A4 mutations are responsible for Pendred syndrome and non-syndromic enlarged vestibular aqueduct (EVA. The mutation spectrum of SLC26A4 varies widely among ethnic groups. To investigate the incidence of EVA in Chinese population and to provide appropriate genetic testing and counseling to patients with SLC26A4 variants, we conducted a large-scale molecular epidemiological survey of SLC26A4.A total of 2352 unrelated non-syndromic hearing loss patients from 27 different regions of China were included. Hot spot regions of SLC26A4, exons 8, 10 and 19 were sequenced. For patients with one allelic variant in the hot spot regions, the other exons were sequenced one by one until two mutant alleles had been identified. Patients with SLC26A4 variants were then examined by temporal bone computed tomography scan for radiological diagnosis of EVA. Ten SLC26A4 variants were cloned for functional study. Confocal microscopy and radioisotope techniques were used to examine the membrane expression of pendrin and transporter function.Of the 86 types of variants found, 47 have never been reported. The ratio of EVA in the Chinese deaf population was at least 11%, and that in patients of Han ethnicity reached at least 13%. The mutational spectrum and mutation detection rate of SLC26A4 are distinct among both ethnicities and regions of Mainland China. Most of the variants caused retention of pendrin in the intracellular region. All the mutant pendrins showed significantly reduced transport capability.An overall description of the molecular epidemiological findings of SLC26A4 in China is provided. The functional assessment procedure can be applied to identification of pathogenicity of variants. These findings are valuable for genetic diagnosis, genetic counseling, prenatal testing and pre-implantation diagnosis in EVA families.

  5. Compensation following bilateral vestibular damage

    Directory of Open Access Journals (Sweden)

    Bill J Yates

    2011-12-01

    Full Text Available Bilateral loss of vestibular inputs affects far fewer patients than unilateral inner ear damage, and thus has been understudied. In both animal subjects and human patients, bilateral vestibular hypofunction (BVH produces a variety of clinical problems, including impaired balance control, inability to maintain stable blood pressure during postural changes, difficulty in visual targeting of images, and disturbances in spatial memory and navigational performance. Experiments in animals have shown that nonlabyrinthine inputs to the vestibular nuclei are rapidly amplified following the onset of BVH, which may explain the recovery of postural stability and orthostatic tolerance that occurs within 10 days. However, the loss of the vestibulo-ocular reflex and degraded spatial cognition appear to be permanent in animals with BVH. Current concepts of the compensatory mechanisms in humans with BVH are largely inferential, as there is a lack of data from patients early in the disease process. Translation of animal studies of compensation for BVH into therapeutic strategies and subsequent application in the clinic is the most likely route to improve treatment. In addition to physical therapy, two types of prosthetic devices have been proposed to treat individuals with bilateral loss of vestibular inputs: those that provide tactile stimulation to indicate body position in space, and those that deliver electrical stimuli to branches of the vestibular nerve in accordance with head movements. The relative efficacy of these two treatment paradigms, and whether they can be combined to facilitate recovery, is yet to be ascertained.

  6. Compensation following bilateral vestibular damage.

    Science.gov (United States)

    McCall, Andrew A; Yates, Bill J

    2011-01-01

    Bilateral loss of vestibular inputs affects far fewer patients than unilateral inner ear damage, and thus has been understudied. In both animal subjects and human patients, bilateral vestibular hypofunction (BVH) produces a variety of clinical problems, including impaired balance control, inability to maintain stable blood pressure during postural changes, difficulty in visual targeting of images, and disturbances in spatial memory and navigational performance. Experiments in animals have shown that non-labyrinthine inputs to the vestibular nuclei are rapidly amplified following the onset of BVH, which may explain the recovery of postural stability and orthostatic tolerance that occurs within 10 days. However, the loss of the vestibulo-ocular reflex and degraded spatial cognition appear to be permanent in animals with BVH. Current concepts of the compensatory mechanisms in humans with BVH are largely inferential, as there is a lack of data from patients early in the disease process. Translation of animal studies of compensation for BVH into therapeutic strategies and subsequent application in the clinic is the most likely route to improve treatment. In addition to physical therapy, two types of prosthetic devices have been proposed to treat individuals with bilateral loss of vestibular inputs: those that provide tactile stimulation to indicate body position in space, and those that deliver electrical stimuli to branches of the vestibular nerve in accordance with head movements. The relative efficacy of these two treatment paradigms, and whether they can be combined to facilitate recovery, is yet to be ascertained.

  7. Inferior vestibular neuritis: 3 cases with clinical features of acute vestibular neuritis, normal calorics but indications of saccular failure

    Directory of Open Access Journals (Sweden)

    Økstad Siri

    2006-12-01

    Full Text Available Abstract Background Vestibular neuritis (VN is commonly diagnosed by demonstration of unilateral vestibular failure, as unilateral loss of caloric response. As this test reflects the function of the superior part of the vestibular nerve only, cases of pure inferior nerve neuritis will be lost. Case presentations We describe three patients with symptoms suggestive of VN, but normal calorics. All 3 had unilateral loss of vestibular evoked myogenic potential. A slight, asymptomatic position dependent nystagmus, with the pathological ear down, was observed. Conclusion We believe that these patients suffer from pure inferior nerve vestibular neuritis.

  8. Vestibular Assessment and Rehabilitation: Ten-Year Survey Trends of Audiologists' Opinions and Practice.

    Science.gov (United States)

    Nelson, M Dawn; Akin, Faith W; Riska, Kristal M; Andresen, Kimberly; Mondelli, Stephanie Stamps

    2016-02-01

    The past decade has yielded changes in the education and training of audiologists and technological advancements that have become widely available for clinical balance function testing. It is unclear if recent advancements in vestibular instrumentation or the transition to an AuD degree have affected audiologists' vestibular clinical practice or opinions. The purpose of this study was to examine predominant opinions and practices for vestibular assessment (VA) and vestibular rehabilitation (VR) over the past decade and between master's- and AuD-level audiologists. A 31-question survey was administered to audiologists via U.S. mail in 2003 (N = 7,500) and electronically in 2014 (N = 9,984) with a response rate of 12% and 10%, respectively. There was an increase in the number of audiologists providing vestibular services in the past decade. Most respondents agreed that audiologists were the most qualified professionals to conduct VA. Less than half of the surveyed audiologists felt that graduate training was adequate for VA. AuD-level audiologists were more satisfied with graduate training and felt more comfortable performing VA compared to master's-level audiologists. Few respondents agreed that audiologists were the most qualified professionals to conduct VR or that graduate training prepared them to conduct VR. The basic vestibular test battery was unchanged across surveys and included: calorics, smooth pursuit, saccades, search for spontaneous, positional, gaze and optokinetic nystagmus, Dix-Hallpike, case history, and hearing evaluation. There was a trend toward greater use of air (versus water) calorics, videonystagmography (versus electronystagmography), and additional tests of vestibular and balance function. VA is a growing specialty area in the field of audiology. Better training opportunities are needed to increase audiologists' knowledge and skills for providing vestibular services. The basic tests performed during VA have remained relatively unchanged

  9. Stereotactic radiotherapy for vestibular schwannoma

    DEFF Research Database (Denmark)

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno

    2014-01-01

    BACKGROUND: Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy. OBJECTIVES: To assess...... the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL......; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014. SELECTION CRITERIA: Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical...

  10. Interactions between Stress and Vestibular Compensation - A Review.

    Science.gov (United States)

    Saman, Yougan; Bamiou, D E; Gleeson, Michael; Dutia, Mayank B

    2012-01-01

    Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are effective in activating the stress axis, and that the acute stress response is important in promoting compensatory synaptic and neuronal plasticity in the vestibular system and cerebellum. The role of stress in human vestibular disorders is complex, and definitive evidence is lacking. This article reviews the evidence from animal and clinical studies with a focus on the effects of stress on the central vestibular pathways and their role in the pathogenesis and management of human vestibular disorders.

  11. Interactions between stress and vestibular compensation – a review

    Directory of Open Access Journals (Sweden)

    Yougan eSaman

    2012-07-01

    Full Text Available Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function, and plasticity have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are effective in activating the stress axis, and that the acute stress response is important in promoting compensatory synaptic and neuronal plasticity in the vestibular system and cerebellum. The role of stress in human vestibular disorders is complex, and definitive evidence is lacking. This article reviews the evidence from animal and clinical studies with a focus on the effects of stress on the central vestibular pathways and their role in the pathogenesis and management of human vestibular disorders.

  12. Interactions between Stress and Vestibular Compensation – A Review

    Science.gov (United States)

    Saman, Yougan; Bamiou, D. E.; Gleeson, Michael; Dutia, Mayank B.

    2012-01-01

    Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are effective in activating the stress axis, and that the acute stress response is important in promoting compensatory synaptic and neuronal plasticity in the vestibular system and cerebellum. The role of stress in human vestibular disorders is complex, and definitive evidence is lacking. This article reviews the evidence from animal and clinical studies with a focus on the effects of stress on the central vestibular pathways and their role in the pathogenesis and management of human vestibular disorders. PMID:22866048

  13. Medial vestibular connections with the hypocretin (orexin) system

    Science.gov (United States)

    Horowitz, Seth S.; Blanchard, Jane; Morin, Lawrence P.

    2005-01-01

    The mammalian medial vestibular nucleus (MVe) receives input from all vestibular endorgans and provides extensive projections to the central nervous system. Recent studies have demonstrated projections from the MVe to the circadian rhythm system. In addition, there are known projections from the MVe to regions considered to be involved in sleep and arousal. In this study, afferent and efferent subcortical connectivity of the medial vestibular nucleus of the golden hamster (Mesocricetus auratus) was evaluated using cholera toxin subunit-B (retrograde), Phaseolus vulgaris leucoagglutinin (anterograde), and pseudorabies virus (transneuronal retrograde) tract-tracing techniques. The results demonstrate MVe connections with regions mediating visuomotor and postural control, as previously observed in other mammals. The data also identify extensive projections from the MVe to regions mediating arousal and sleep-related functions, most of which receive immunohistochemically identified projections from the lateral hypothalamic hypocretin (orexin) neurons. These include the locus coeruleus, dorsal and pedunculopontine tegmental nuclei, dorsal raphe, and lateral preoptic area. The MVe itself receives a projection from hypocretin cells. CTB tracing demonstrated reciprocal connections between the MVe and most brain areas receiving MVe efferents. Virus tracing confirmed and extended the MVe afferent connections identified with CTB and additionally demonstrated transneuronal connectivity with the suprachiasmatic nucleus and the medial habenular nucleus. These anatomical data indicate that the vestibular system has access to a broad array of neural functions not typically associated with visuomotor, balance, or equilibrium, and that the MVe is likely to receive information from many of the same regions to which it projects.

  14. Neuropharmacological basis of vestibular system disorder treatment.

    Science.gov (United States)

    Soto, Enrique; Vega, Rosario; Seseña, Emmanuel

    2013-01-01

    This work reviews the neuropharmacology of the vestibular system, with an emphasis on the mechanism of action of drugs used in the treatment of vestibular disorders. Clinicians are confronted with a rapidly changing field in which advances in the knowledge of ionic channel function and synaptic transmission mechanisms have led to the development of new scientific models for the understanding of vestibular dysfunction and its management. In particular, there have been recent advances in our knowledge of the fundamental mechanisms of vestibular system function and of drug action. In this work, drugs acting on vestibular system have been grouped into two main categories according to their primary mechanisms of action: those with effects on neurotransmitters and neuromodulators dynamics and those that act on voltage-gated ion channels. Particular attention is given in this review to drugs that may provide additional insight into the pathophysiology of vestibular diseases. The critical analysis of the literature reveals that there is a significant lack of information defining the real utility of diverse drugs used in clinical practice. The development of basic studies addressing drug actions at the molecular, cellular and systems level, combined with reliable and well controlled clinical trials, would provide the scientific basis for new strategies for the treatment of vestibular disorders.

  15. Brain Activations for Vestibular Stimulation and Dual Tasking Change with Spaceflight

    Science.gov (United States)

    Yuan, Peng; Koppelmans, Vincent; Reuter-Lorenz, Patricia; De Dios, Yiri; Gadd, Nichole; Wood, Scott; Riascos, Roy; Kofman, Igor; Bloomberg, Jacob; Mulavara, Ajitkumar; hide

    2017-01-01

    Previous studies have documented the effects of spaceflight on human physiology and behavior, including muscle mass, cardiovascular function, gait, balance, manual motor control, and cognitive performance. An understanding of spaceflight-related changes provides important information about human adaptive plasticity and facilitates future space travel. In the current study, we evaluated how brain activations associated with vestibular stimulation and dual tasking change as a function of spaceflight. Five crewmembers were included in this study. The durations of their spaceflight missions ranged from 3 months to 7 months. All of them completed at least two preflight assessments and at least one postflight assessment. The preflight sessions occurred, on average, about 198 days and 51 days before launch; the first postflight sessions were scheduled 5 days after return. Functional MRI was acquired during vestibular stimulation and dual tasking, at each session. Vestibular stimulation was administered via skull taps delivered by a pneumatic tactile pulse system placed over the lateral cheekbones. The magnitude of brain activations for vestibular stimulation increased with spaceflight relative to the preflight levels, in frontal areas and the precuneus. In addition, longer flight duration was associated with greater preflight-to-postflight increases in vestibular activation in frontal regions. Functional MRI for finger tapping was acquired during both single-task (finger tapping only) and dual-task (simultaneously performing finger tapping and a secondary counting task) conditions. Preflight-to-post-spaceflight decreases in brain activations for dual tasking were observed in the right postcentral cortex. An association between flight duration and amplitude of flight-related change in activations for dual tasking was observed in the parietal cortex. The spaceflight-related increase in vestibular brain activations suggests that after a long-term spaceflight, more neural

  16. Evaluation of Galvanic Vestibular Stimulation System

    Science.gov (United States)

    Kofman, I. S.; Warren, E.; DeSoto, R.; Moroney, G.; Chastain, J.; De Dios, Y. E.; Gadd, N.; Taylor, L.; Peters, B. T.; Allen, E.; hide

    2017-01-01

    Microgravity exposure results in an adaptive central reinterpretation of information from multiple sensory sources to produce a sensorimotor state appropriate for motor actions in this unique environment, but this new adaptive state is no longer appropriate for the 1-g gravitational environment on Earth. During these gravitational transitions, astronauts experience deficits in both perceptual and motor functions including impaired postural control, disruption in spatial orientation, impaired control of locomotion that include alterations in muscle activation variability, modified lower limb kinematics, alterations in head-trunk coordination as well as reduced dynamic visual acuity. Post-flight changes in postural and locomotor control might have adverse consequences if a rapid egress was required following a long-duration mission, where support personnel may not be available to aid crewmembers. The act of emergency egress includes, but is not limited to standing, walking, climbing a ladder, jumping down, monitoring displays, actuating discrete controls, operating auxiliary equipment, and communicating with Mission Control and recovery teams while maintaining spatial orientation, mobility and postural stability in order to escape safely. The average time to recover impaired postural control and functional mobility to preflight levels of performance has been shown to be approximately two weeks after long-duration spaceflight. The postflight alterations are due in part to central reinterpretation of vestibular information caused by exposure to microgravity. In this study we will use a commonly used technique of transcutaneous electrical stimulation applied across the vestibular end organs (galvanic vestibular stimulation, GVS) to disrupt vestibular function as a simulation of post-flight disturbances. The goal of this project is an engineering human-in-the-loop evaluation of a device that can degrade performance of functional tasks (e.g. to maintain upright balance

  17. Functional Testing of SLC26A4 Variants-Clinical and Molecular Analysis of a Cohort with Enlarged Vestibular Aqueduct from Austria.

    Science.gov (United States)

    Roesch, Sebastian; Bernardinelli, Emanuele; Nofziger, Charity; Tóth, Miklós; Patsch, Wolfgang; Rasp, Gerd; Paulmichl, Markus; Dossena, Silvia

    2018-01-10

    The prevalence and spectrum of sequence alterations in the SLC26A4 gene, which codes for the anion exchanger pendrin, are population-specific and account for at least 50% of cases of non-syndromic hearing loss associated with an enlarged vestibular aqueduct. A cohort of nineteen patients from Austria with hearing loss and a radiological alteration of the vestibular aqueduct underwent Sanger sequencing of SLC26A4 and GJB2, coding for connexin 26. The pathogenicity of sequence alterations detected was assessed by determining ion transport and molecular features of the corresponding SLC26A4 protein variants. In this group, four uncharacterized sequence alterations within the SLC26A4 coding region were found. Three of these lead to protein variants with abnormal functional and molecular features, while one should be considered with no pathogenic potential. Pathogenic SLC26A4 sequence alterations were only found in 12% of patients. SLC26A4 sequence alterations commonly found in other Caucasian populations were not detected. This survey represents the first study on the prevalence and spectrum of SLC26A4 sequence alterations in an Austrian cohort and further suggests that genetic testing should always be integrated with functional characterization and determination of the molecular features of protein variants in order to unequivocally identify or exclude a causal link between genotype and phenotype.

  18. Clinical Evaluation of the Vestibular Nerve Using Vestibular Evoked Myogenic Potentials.

    Science.gov (United States)

    Bogle, Jamie M

    2018-01-01

    Vestibular evoked myogenic potentials are currently the most clinically accessible method to evaluate the otolith reflex pathways. These responses provide unique information regarding the status of the utriculo-ocular and sacculo-collic reflex pathways, information that has previously been unavailable. Vestibular evoked myogenic potentials are recorded from tonically contracted target muscles known to be innervated by these respective otolith organs. Diagnosticians can use vestibular evoked myogenic potentials to better evaluate the overall integrity of the inner ear and neural pathways; however, there are specific considerations for each otolith reflex protocol. In addition, specific patient populations may require protocol variations to better evaluate atypical function of the inner ear organs, vestibular nerve transmission, or subsequent reflex pathways. This is a review of the clinical application and interpretation of cervical and ocular vestibular evoked myogenic potentials.

  19. Tissue-Specific Effects of Bariatric Surgery Including Mitochondrial Function

    Directory of Open Access Journals (Sweden)

    Simon N. Dankel

    2011-01-01

    Full Text Available A better understanding of the molecular links between obesity and disease is potentially of great benefit for society. In this paper we discuss proposed mechanisms whereby bariatric surgery improves metabolic health, including acute effects on glucose metabolism and long-term effects on metabolic tissues (adipose tissue, skeletal muscle, and liver and mitochondrial function. More short-term randomized controlled trials should be performed that include simultaneous measurement of metabolic parameters in different tissues, such as tissue gene expression, protein profile, and lipid content. By directly comparing different surgical procedures using a wider array of metabolic parameters, one may further unravel the mechanisms of aberrant metabolic regulation in obesity and related disorders.

  20. Genetic disorders of the vestibular system.

    Science.gov (United States)

    Eppsteiner, Robert W; Smith, Richard J H

    2011-10-01

    This review highlights the current body of literature related to the genetics of inherited vestibular disorders and provides a framework for the characterization of these disorders. We emphasize peripheral causes of vestibular dysfunction and highlight recent advances in the field, point out gaps in understanding, and focus on key areas for future investigation. The discovery of a modifier gene that leads to a more severe Usher syndrome phenotype calls into question the assumption that Usher syndrome is universally a monogenic disorder. Despite the use of several investigational approaches, the genetic basis of Menière's disease remains poorly understood. Evidence for a vestibular phenotype associated with DFNB1 suggests that mutations in other genes causally related to nonsyndromic hearing loss also may have an unrecognized vestibular phenotype. Our understanding of the genetic basis for vestibular disorders is superficial. Significant challenges include defining the genetics of inherited isolated vestibular dysfunction and understanding the pathological basis of Menière's disease. However, improved characterization of inherited vestibular dysfunction, coupled with advanced genetic techniques such as targeted genome capture and massively parallel sequencing, provides an opportunity to investigate these diseases at the genetic level.

  1. Embryological development and large vestibular aqueduct syndrome.

    Science.gov (United States)

    Pyle, G M

    2000-11-01

    Large vestibular aqueduct syndrome (LVAS) is a significant cause of hearing loss in early childhood. Many theories on the origins and causes of LVAS have been proposed, including arrest or maldevelopment of the vestibular labyrinth in embryonic life. Prior studies have described postnatal and adult vestibular aqueduct anatomy, but none has analyzed aqueduct growth throughout embryonic life. This study was undertaken to characterize the growth of the developing vestibular aqueduct to gain a better understanding of the possible origins of LVAS. Basic science, temporal bone histopathological study. Serial sections from 48 temporal bones from human embryos ranging in age from 5 weeks' gestation to full term were studied with computer image analysis. Measurements of vestibular aqueduct internal and external aperture, midportion diameter, and length were analyzed to obtain a growth model of development. The vestibular aqueduct grows in a nonlinear fashion throughout embryonic life. All parameters fit a similar growth curve and never reached a maximum or began narrowing during development. Growth in one parameter correlated well with growth of another. There was good side-to-side correlation with all but the external aperture. Most of the membranous labyrinth reaches adult size by 20 weeks' gestation, but the vestibular aqueduct grows throughout embryonic life. The measurements and growth model obtained in this study are not consistent with the theory that LVAS results from an arrest in development early in fetal life. The data suggest that LVAS may result from postnatal and early childhood maldevelopment.

  2. Common Vestibular Disorders

    OpenAIRE

    Balatsouras, Dimitrios G

    2017-01-01

    The three most common vestibular diseases, benign paroxysmal positional vertigo (BPPV), Meniere's disease (MD) and vestibular neuritis (VN), are presented in this paper. BPPV, which is the most common peripheral vestibular disorder, can be defined as transient vertigo induced by a rapid head position change, associated with a characteristic paroxysmal positional nystagmus. Canalolithiasis of the posterior semicircular canal is considered the most convincing theory of its pathogenesis and the ...

  3. The chronic infusion of nicotine into the developing chick embryo does not alter the density of (-)-[3H]nicotine-binding sites or vestibular function

    Science.gov (United States)

    Roll, R. L.; Jones, T. A.; Benowitz, N. L.; Morley, B. J.

    1993-01-01

    (-)-Nicotine (1.2 mg/day) or saline was infused into chick embryos (Gallus domesticus) for 10 days beginning 12 h beyond the eight day of incubation (E8 + 12 h). Twelve h beyond the eighteenth day of incubation (E18 + 12 h), the eggs were opened to access the embryos and subcutaneous skull electrodes placed. Short latency vestibular response thresholds and input/output functions were determined to assess neurophysiological consequences of chronic nicotine administration. Samples of serum and extraembryonic (amniotic and albumen) fluid were analyzed by gas chromatography-mass spectrometry to determine the levels of nicotine and its major metabolite, cotinine. The brains were removed and divided into diencephalon and mesencephalon and the density of (-)-[3H]nicotine binding sites in each brain area was measured. Nicotine and cotinine were found in the serum and extraembryonic fluid, but nicotinic receptors were not up-regulated in the brains of animals infused with nicotine in comparison to controls. Vestibular response thresholds also did not differ between nicotine-treated and control animals.

  4. Clinical vestibular testing assessed with machine-learning algorithms.

    Science.gov (United States)

    Priesol, Adrian J; Cao, Mengfei; Brodley, Carla E; Lewis, Richard F

    2015-04-01

    Dizziness and imbalance are common clinical problems, and accurate diagnosis depends on determining whether damage is localized to the peripheral vestibular system. Vestibular testing guides this determination, but the accuracy of the different tests is not known. To determine how well each element of the vestibular test battery segregates patients with normal peripheral vestibular function from those with unilateral reductions in vestibular function. Retrospective analysis of vestibular test batteries in 8080 patients. Clinical medical records were reviewed for a subset of individuals with the reviewers blinded to the vestibular test data. A group of machine-learning classifiers were trained using vestibular test data from persons who were "manually" labeled as having normal vestibular function or unilateral vestibular damage based on a review of their medical records. The optimal trained classifier was then used to categorize patients whose diagnoses were unknown, allowing us to determine the information content of each element of the vestibular test battery. The information provided by each element of the vestibular test battery to segregate individuals with normal vestibular function from those with unilateral vestibular damage. The time constant calculated from the rotational test ranked first in information content, and measures that were related physiologically to the rotational time constant were 10 of the top 12 highest-ranked variables. The caloric canal paresis ranked eighth, and the other elements of the test battery provided minimal additional information. The sensitivity of the rotational time constant was 77.2%, and the sensitivity of the caloric canal paresis was 59.6%; the specificity of the rotational time constant was 89.0%, and the specificity of the caloric canal paresis was 64.9%. The diagnostic accuracy of the vestibular test battery increased from 72.4% to 93.4% when the data were analyzed with the optimal machine-learning classifier

  5. Variables associated with outcome in patients with bilateral vestibular hypofunction: Preliminary study.

    Science.gov (United States)

    Herdman, Susan J; Hall, Courtney D; Maloney, Brian; Knight, Sara; Ebert, Marti; Lowe, Jessica

    2015-01-01

    Vestibular rehabilitation (VR) improves symptoms and function in some but not all patients with bilateral vestibular hypofunction (BVH). The purpose of this retrospective study was to examine change following vestibular rehabilitation and to identify factors associated with rehabilitation outcome in patients with BVH. Data from 69 patients with BVH were analyzed. Factors studied included patient characteristics, subjective complaints and physical function. Outcome measures included symptom intensity, balance confidence, quality of life, gait speed, fall risk, and dynamic visual acuity. Bivariate correlations were used to examine relationships of patient characteristics and baseline measures with outcome measures. One-way ANOVAs were used to compare outcomes in patients with BVH versus unilateral vestibular hypofunction (UVH). As a group, patients with BVH improved in all outcome measures except disability following a course of vestibular rehabilitation (VR); however, only 38-86% demonstrated a meaningful improvement, depending on the specific outcome measure examined. Several factors measured at baseline - age, DGI score, gait speed and perceived dysequilibrium - were associated with outcomes. For example, greater age was related to higher DVA scores at discharge; lower initial DGI scores were related to higher Disability scores at discharge. Compared to patients with UVH, reported previously [9], a smaller percentage of patients with BVH improve and to a lesser extent. Consideration of baseline factors may provide guidance for setting patient goals. Further research is needed determine what factors predict outcome and to develop more effective treatment strategies for those patients who do not improve.

  6. Interactions between Stress and Vestibular Compensation – A Review

    OpenAIRE

    Saman, Yougan; Bamiou, D. E.; Gleeson, Michael; Dutia, Mayank B

    2012-01-01

    Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are effective in activating the stress axis, and that the acute stress response is important in promoting...

  7. The Moving History of Vestibular Stimulation as a Therapeutic Intervention

    OpenAIRE

    Grabherr, Luzia; Lenggenhager, Bigna; Macauda, Gianluca

    2015-01-01

    Although the discovery and understanding of the function of the vestibular system date back only to the 19th century, strategies that involve vestibular stimulation were used long before to calm, soothe and even cure people. While such stimulation was classically achieved with various motion devices, like Cox’s chair or Hallaran’s swing, the development of caloric and galvanic vestibular stimulation has opened up new possibilities in the 20th century. With the increasing knowledge and recogni...

  8. Evaluation of diagnostic tests of the otolith organs and their application in various vestibular pathologies

    NARCIS (Netherlands)

    Winters, S.M.

    2014-01-01

    Current vestibular testing is limited. The general function of the vestibular system on both sides of the head can be tested, and one part of the peripheral vestibular organ, the horizontal semicircular canal, can be tested unilaterally. However, recently a test for the function of the otolith

  9. Nitric oxide in the rat vestibular system.

    Science.gov (United States)

    Harper, A; Blythe, W R; Zdanski, C J; Prazma, J; Pillsbury, H C

    1994-10-01

    Nitric oxide is known to function as a neurotransmitter in the central nervous system. It is also known to be involved in the central nervous system excitatory amino acid neurotransmission cascade. Activation of excitatory amino acid receptors causes an influx of calcium, which activates nitric oxide synthase. The resulting increase in intracellular nitric oxide activates soluble guanylate cyclase, leading to a rise in cyclic guanosine monophosphate. The excitatory amino acids glutamate and aspartate are found in the vestibular system and have been postulated to function as vestibular system neurotransmitters. Although nitric oxide has been investigated as a neurotransmitter in other tissues, no published studies have examined the role of nitric oxide in the vestibular system. Neuronal NADPH-diaphorase has been characterized as a nitric oxide synthase. This enzyme catalyzes the conversion of L-arginine to L-citrulline, producing nitric oxide during the reaction. We used a histochemical stain characterized by Hope et al. (Proc Natl Acad Sci 1991;88:2811) as specific for neuronal nitric oxide synthase to localize the enzyme in the rat vestibular system. An immunocytochemical stain was used to examine rat inner ear tissue for the presence of the enzyme's end product, L-citrulline, thereby demonstrating nitric oxide synthase activity. Staining of vestibular ganglion sections showed nitric oxide synthase presence and activity in ganglion cells and nerve fibers. These results indicate the presence of active nitric oxide synthase in these tissues and suggest modulation of vestibular neurotransmission by nitric oxide.

  10. Sensorintegrative dysfunction underlying vestibular disorders after traumatic brain injury: a review.

    Science.gov (United States)

    Franke, Laura M; Walker, William C; Cifu, David X; Ochs, Alfred L; Lew, Henry L

    2012-01-01

    Vestibular symptoms are persistent and problematic sequelae of blast exposure. Several lines of evidence suggest that these symptoms often stem from injury to the central nervous system. Current methods of assessing the vestibular system have described vestibular deficits that follow traumatic brain injury and differentiate blunt and blast trauma but have not examined the full range of vestibular functions that depend on the cerebral structures above the midbrain. Damage to the central vestibular circuits can lead to deficits in vital processes of spatial perception and navigation, in addition to dizziness and disequilibrium, and may also affect emotional functioning, particularly noradrenergically modulated states of anxiety. Perceptual functions can be assessed to determine the extent of central nervous system involvement in vestibular symptoms and to provide greater confidence when vestibular dysfunction is to be excluded. The ability to detect central vestibular dysfunction will significantly enhance our response to the dizziness and balance symptoms that are a common source of distress for Veterans.

  11. Bionic balance organs: progress in the development of vestibular prostheses.

    Science.gov (United States)

    Smith, Paul F

    2017-09-01

    The vestibular system is a sensory system that is critically important in humans for gaze and image stability as well as postural control. Patients with complete bilateral vestibular loss are severely disabled and experience a poor quality of life. There are very few effective treatment options for patients with no vestibular function. Over the last 10 years, rapid progress has been made in developing artificial 'vestibular implants' or 'prostheses', based on cochlear implant technology. As of 2017, 13 patients worldwide have received vestibular implants and the results are encouraging. Vestibular implants are now becoming part of an increasing effort to develop artificial, bionic sensory systems, and this paper provides a review of the progress in this area.

  12. Vestibular evoked myogenic potential

    Directory of Open Access Journals (Sweden)

    Felipe, Lilian

    2012-01-01

    Full Text Available Introduction: The Vestibular Evoked Myogenic Potential (VEMP is a promising test for the evaluation of the cholic descending vestibular system. This reflex depends of the integrity from the saccular macula, from the inferior vestibular nerve, the vestibular nuclei, the vestibule-spinal tract and effectors muscles. Objective: Perform a systematic review of the pertinent literature by means of database (COCHRANE, MEDLINE, LILACS, CAPES. Conclusion: The clinical application of the VEMP has expanded in the last years, as goal that this exam is used as complementary in the otoneurological evaluation currently used. But, methodological issues must be clarified. This way, this method when combined with the standard protocol, can provide a more widely evaluation from the vestibular system. The standardization of the methodology is fundamental criterion for the replicability and sensibility of the exam.

  13. Unilateral Vestibular Loss Impairs External Space Representation

    Science.gov (United States)

    Borel, Liliane; Redon-Zouiteni, Christine; Cauvin, Pierre; Dumitrescu, Michel; Devèze, Arnaud; Magnan, Jacques; Péruch, Patrick

    2014-01-01

    The vestibular system is responsible for a wide range of postural and oculomotor functions and maintains an internal, updated representation of the position and movement of the head in space. In this study, we assessed whether unilateral vestibular loss affects external space representation. Patients with Menière's disease and healthy participants were instructed to point to memorized targets in near (peripersonal) and far (extrapersonal) spaces in the absence or presence of a visual background. These individuals were also required to estimate their body pointing direction. Menière's disease patients were tested before unilateral vestibular neurotomy and during the recovery period (one week and one month after the operation), and healthy participants were tested at similar times. Unilateral vestibular loss impaired the representation of both the external space and the body pointing direction: in the dark, the configuration of perceived targets was shifted toward the lesioned side and compressed toward the contralesioned hemifield, with higher pointing error in the near space. Performance varied according to the time elapsed after neurotomy: deficits were stronger during the early stages, while gradual compensation occurred subsequently. These findings provide the first demonstration of the critical role of vestibular signals in the representation of external space and of body pointing direction in the early stages after unilateral vestibular loss. PMID:24523916

  14. Unilateral vestibular loss impairs external space representation.

    Directory of Open Access Journals (Sweden)

    Liliane Borel

    Full Text Available The vestibular system is responsible for a wide range of postural and oculomotor functions and maintains an internal, updated representation of the position and movement of the head in space. In this study, we assessed whether unilateral vestibular loss affects external space representation. Patients with Menière's disease and healthy participants were instructed to point to memorized targets in near (peripersonal and far (extrapersonal spaces in the absence or presence of a visual background. These individuals were also required to estimate their body pointing direction. Menière's disease patients were tested before unilateral vestibular neurotomy and during the recovery period (one week and one month after the operation, and healthy participants were tested at similar times. Unilateral vestibular loss impaired the representation of both the external space and the body pointing direction: in the dark, the configuration of perceived targets was shifted toward the lesioned side and compressed toward the contralesioned hemifield, with higher pointing error in the near space. Performance varied according to the time elapsed after neurotomy: deficits were stronger during the early stages, while gradual compensation occurred subsequently. These findings provide the first demonstration of the critical role of vestibular signals in the representation of external space and of body pointing direction in the early stages after unilateral vestibular loss.

  15. Vestibular schwannoma: negative growth and audiovestibular features.

    Science.gov (United States)

    Stipkovits, E M; Graamans, K; Van Dijk, J E

    2001-11-01

    At the University Medical Center Utrecht, non-operative management was used for 44 patients with a unilateral vestibular schwannoma between 1990 and 1997. During that period, consecutive tumor sizes were determined by magnetic resonance imaging. Three of the 44 patients showed an average decrease in tumor size of 16.7% according to American Academy of Otolaryngology-Head and Neck Surgery standards. This study describes the initial vestibular status and audiometric changes measured over up to 10 years in these three patients. Vestibular function was determined once, by means of the bithermal caloric test, the torsion test, the saccade test, the smooth pursuit test, and the registration of spontaneous nystagmus. The three patients had severe vestibular paresis on the affected side. Pure-tone and speech audiometry were performed at regular intervals. Although the size of their tumors decreased, their hearing gradually deteriorated, just as it does in the majority of patients with a growing or stable vestibular schwannoma. The observations presented here suggest that the development of symptoms in a vestibular schwannoma does not differentiate between patients with a stable, growing or shrinking tumor. The development of symptoms may be the result of the same pathogenetic mechanism.

  16. Deregulated genes in sporadic vestibular schwannomas

    DEFF Research Database (Denmark)

    Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea; Stangerup, Sven-Eric

    2010-01-01

    In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology....

  17. Evaluation of postural control in unilateral vestibular hypofunction

    Directory of Open Access Journals (Sweden)

    Rafaela Maia Quitschal

    2014-07-01

    Full Text Available INTRODUCTION: Patients with vestibular hypofunction, a typical finding in peripheral vestibular disorders, show body balance alterations. OBJECTIVE: To evaluate the postural control of patients with vertigo and unilateral vestibular hypofunction. METHOD: This is a clinical cross-sectional study. Twenty-five patients with vertigo and unilateral vestibular hypofunction and a homogeneous control group consisting of 32 healthy individuals were submitted to a neurotological evaluation including the Tetrax Interactive Balance System posturography in eight different sensory conditions. RESULTS: For different positions, vertiginous patients with unilateral vestibular hypofunction showed significantly higher values of general stability index, weight distribution index, right/left and tool/heel synchronizations, Fourier transformation index and fall index than controls. CONCLUSION: Increased values in the indices of weight distribution, right/left and tool/heel synchronizations, Fourier transformation and fall risk characterize the impairment of postural control in patients with vertigo and unilateral vestibular hypofunction.

  18. Idiopathic scoliosis and the vestibular system.

    Science.gov (United States)

    Hawasli, Ammar H; Hullar, Timothy E; Dorward, Ian G

    2015-02-01

    Despite its high prevalence, the etiology underlying idiopathic scoliosis remains unclear. Although initial scrutiny has focused on genetic, biochemical, biomechanical, nutritional and congenital causes, there is growing evidence that aberrations in the vestibular system may play a role in the etiology of scoliosis. In this article, we discuss putative mechanisms for adolescent idiopathic scoliosis and review the current evidence supporting a role for the vestibular system in adolescent idiopathic scoliosis. A comprehensive search of the English literature was performed using PubMed ( http://www.ncbi.nlm.nih.gov/pubmed ). Research articles studying interactions between adolescent idiopathic scoliosis and the vestibular system were selected and evaluated for inclusion in a literature review. Eighteen manuscripts of level 3-4 clinical evidence to support an association between adolescent idiopathic scoliosis (AIS) and dysfunction of the vestibular system were identified. These studies include data from physiologic and morphologic studies in humans. Clinical data are supported by animal model studies to suggest a causative link between the vestibular system and AIS. Clinical data and a limited number of animal model studies suggest a causative role of the vestibular system in AIS, although this association has not been reproduced in all studies.

  19. The History and Evolution of Surgery on the Vestibular Labyrinth.

    Science.gov (United States)

    Naples, James G; Eisen, Marc D

    2016-11-01

    The history of surgery on the vestibular labyrinth is rich but sparsely documented in the literature. The story begins over a century ago with the labyrinthectomy in an era that consisted exclusively of ablative surgery for infection or vertigo. Improved understanding of vestibular physiology and pathology produced an era of selective ablation and hearing preservation that includes semicircular canal occlusion for benign paroxysmal positional vertigo. An era of restoration began with a discovery of superior semicircular canal dehiscence and its repair. The final era of vestibular replacement is upon us as the possibility of successful prosthetic vestibular implantation becomes reality. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  20. Periosteal Pedicle Flap Harvested during Vestibular Extension for Root Coverage

    Directory of Open Access Journals (Sweden)

    Shubham Kumar

    2015-01-01

    Full Text Available Root exposure along with inadequate vestibular depth is a common clinical finding. Treatment option includes many techniques to treat such defects for obtaining predictable root coverage. Normally, the vestibular depth is increased first followed by a second surgery for root coverage. The present case report describes a single-stage technique for vestibular extension and root coverage in a single tooth by using the Periosteal Pedicle Flap (PPF. This technique involves no donor site morbidity and allows for reflection of sufficient amount of periosteal flap tissue with its own blood supply at the surgical site, thus increasing the chances of success of root coverage with simultaneous increase in vestibular depth.

  1. Can a finding of cervical vestibular evoked myogenic potentials contribute to vestibular migraine diagnostics?

    Directory of Open Access Journals (Sweden)

    Tihana Vešligaj

    2016-02-01

    Full Text Available Aim To investigate differences in vestibular evoked myogenic potentials (VEMP results with patients suffering from vestibular migraine and healthy people, taking into consideration values of threshold and latency of occurrence of the characteristic wave complex, size of amplitude, and interaural amplitude ratio. According to the results, determine the importance and usefulness of VEMP in vestibular migraine diagnostics. Methods A total number of 62 subjects were included in the study, 32 of them belonging to a group of patients suffering from vestibular migraine (VM, while other 30 were in a control group of healthy subjects. Information was collected during the diagnostic evaluation. General and otoneurological history of patients and bedside tests, audiological results, videonystagmography and cervical vestibular evoked myogenic potentials (cVEMP were made. Results There was a difference in an interaural ratio of amplitudes in the experimental and control groups, but it was not found to be clinically significant. By ToneBurst 500 Hz method, the interaural amplitude ratio higher than 35% was measured in 46.97% subjects, while the response was totally unilaterally missing in 28.8% patients. Conclusion Even the sophisticated method as cVEMP does not give the ultimate result confirming the vestibular migraine diagnosis, and neither do other diagnostic methods. cVEMP result can contribute to the completion of full mosaic of vestibular migraine diagnostics.

  2. Sensorintegrative dysfunction underlying vestibular disorders after traumatic brain injury: A review

    OpenAIRE

    Laura M. Franke, PhD; William C. Walker, MD; David X. Cifu, MD; Alfred L. Ochs, PhD; Henry L. Lew, MD, PhD

    2012-01-01

    Vestibular symptoms are persistent and problematic sequelae of blast exposure. Several lines of evidence suggest that these symptoms often stem from injury to the central nervous system. Current methods of assessing the vestibular system have described vestibular deficits that follow traumatic brain injury and differentiate blunt and blast trauma but have not examined the full range of vestibular functions that depend on the cerebral structures above the midbrain. Damage to the central vestib...

  3. [Anatomy and physiology of the vestibular system: review of the literature].

    Science.gov (United States)

    Sakka, L; Vitte, E

    2004-10-01

    The vestibular system is a complex system involving not only posterior labyrinth but also central structures such as cerebellum, striatum, thalamus, frontal and prefrontal cortex to assure balance, movements and walking. Information reaching the vestibular complex are not purely vestibular but also from visual, somatosensory and cerebellar origins. The equilibrium is also a complex physiological function needing concordance of vestibular, visual and somatosensory information or either central compensation after an injury but also an integrity of the central nervous system.

  4. An integrated vestibular-cochlear prosthesis for restoring balance and hearing.

    Science.gov (United States)

    Lu, Thomas; Djalilian, Hamid; Zeng, Fan-Gang; Chen, Hongbin; Sun, Xiaoan

    2011-01-01

    An integrated vestibular-cochlear implant can be rapidly prototyped and clinically tested by modifying an existing modern cochlear implant. The modifications include addition of gyroscope sensors and reallocation of several electrodes that are normally used for auditory nerve stimulation to the semicircular canals, while sharing the external DSP processor and the internal receiver/stimulator. This paper discusses the validation issues related to hardware and software design that arise in integrating electric hearing and balance onto a single device. The device's initially targeted population will be deaf individuals who also have vestibular impairment since there is a strong ethical justification for vestibular implantation along with minimal additional surgical risk. Because of widespread usage of ototoxic drugs and unique genetic mutations, the patient population with both impaired hearing and balance function is especially prevalent in Asian countries such as China and India. Should such an integrated vestibular-cochlear implant be verified, it could be used to restore balance or treat a wide array of vestibular disorders.

  5. The Modulation of Hippocampal Theta Rhythm by the Vestibular System.

    Science.gov (United States)

    Aitken, Phillip; Zheng, Yiwen; Smith, Paul F

    2017-11-22

    The vestibular system is a sensory system that has evolved over millions of years to detect acceleration of the head, both rotational and translational, in three dimensions. One of its most important functions is to stabilize gaze during unexpected head movement; however, it is also important in the control of posture and autonomic reflexes. Theta rhythm is a 3-12 Hz oscillating EEG signal that is intimately linked to self-motion and is also known to be important in learning and memory. Many studies over the last two decades have shown that selective activation of the vestibular system, either using natural rotational or translational stimulation, or electrical stimulation of the peripheral vestibular system, can induce and modulate theta activity. Furthermore, inactivation of the vestibular system has been shown to significantly reduce theta in freely moving animals, which may be linked to its impairment of place cell function as well as spatial learning and memory. The pathways through which vestibular information modulate theta rhythm remain debatable. However, vestibular responses have been found in the pedunculopontine tegmental nucleus (PPTg) and activation of the vestibular system causes an increase in acetylcholine release into the hippocampus, probably from the medial septum. Therefore, a pathway from the vestibular nucleus complex and/or cerebellum to the PPTg, supramammillary nucleus, posterior hypothalamic nucleus and the septum, to the hippocampus, is likely. The modulation of theta by the vestibular system may have implications for vestibular effects on cognitive function and the contribution of vestibular impairment to the risk of dementia. Copyright © 2017, Journal of Neurophysiology.

  6. The thalamocortical vestibular system in animals and humans.

    Science.gov (United States)

    Lopez, Christophe; Blanke, Olaf

    2011-06-24

    The vestibular system provides the brain with sensory signals about three-dimensional head rotations and translations. These signals are important for postural and oculomotor control, as well as for spatial and bodily perception and cognition, and they are subtended by pathways running from the vestibular nuclei to the thalamus, cerebellum and the "vestibular cortex." The present review summarizes current knowledge on the anatomy of the thalamocortical vestibular system and discusses data from electrophysiology and neuroanatomy in animals by comparing them with data from neuroimagery and neurology in humans. Multiple thalamic nuclei are involved in vestibular processing, including the ventroposterior complex, the ventroanterior-ventrolateral complex, the intralaminar nuclei and the posterior nuclear group (medial and lateral geniculate nuclei, pulvinar). These nuclei contain multisensory neurons that process and relay vestibular, proprioceptive and visual signals to the vestibular cortex. In non-human primates, the parieto-insular vestibular cortex (PIVC) has been proposed as the core vestibular region. Yet, vestibular responses have also been recorded in the somatosensory cortex (area 2v, 3av), intraparietal sulcus, posterior parietal cortex (area 7), area MST, frontal cortex, cingulum and hippocampus. We analyze the location of the corresponding regions in humans, and especially the human PIVC, by reviewing neuroimaging and clinical work. The widespread vestibular projections to the multimodal human PIVC, somatosensory cortex, area MST, intraparietal sulcus and hippocampus explain the large influence of vestibular signals on self-motion perception, spatial navigation, internal models of gravity, one's body perception and bodily self-consciousness. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Longitudinal performance of an implantable vestibular prosthesis.

    Science.gov (United States)

    Phillips, Christopher; Ling, Leo; Oxford, Trey; Nowack, Amy; Nie, Kaibao; Rubinstein, Jay T; Phillips, James O

    2015-04-01

    Loss of vestibular function may be treatable with an implantable vestibular prosthesis that stimulates semicircular canal afferents with biphasic pulse trains. Several studies have demonstrated short-term activation of the vestibulo-ocular reflex (VOR) with electrical stimulation. Fewer long-term studies have been restricted to small numbers of animals and stimulation designed to produce adaptive changes in the electrically elicited response. This study is the first large consecutive series of implanted rhesus macaque to be studied longitudinally using brief stimuli designed to limit adaptive changes in response, so that the efficacy of electrical activation can be studied over time, across surgeries, canals and animals. The implantation of a vestibular prosthesis in animals with intact vestibular end organs produces variable responses to electrical stimulation across canals and animals, which change in threshold for electrical activation of eye movements and in elicited slow phase velocities over time. These thresholds are consistently lower, and the slow phase velocities higher, than those obtained in human subjects. The changes do not appear to be correlated with changes in electrode impedance. The variability in response suggests that empirically derived transfer functions may be required to optimize the response of individual canals to a vestibular prosthesis, and that this function may need to be remapped over time. This article is part of a Special Issue entitled . Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Efficacy of vestibular rehabilitation on chronic unilateral vestibular dysfunction.

    Science.gov (United States)

    Topuz, Oya; Topuz, Bülent; Ardiç, F Necdet; Sarhuş, Merih; Ogmen, Gülsen; Ardiç, Füsun

    2004-02-01

    To assess the efficacy of vestibular rehabilitation exercises on patients with chronic unilateral vestibular dysfunction. Prospective study. Physical Medicine and Rehabilitation Clinic and Otolaryngology Clinic of a tertiary referral hospital. One-hundred and twenty-five patients with unilateral chronic vestibular dysfunction were included in the study. Eight-week, two-staged (clinic and home) vestibular rehabilitation programme with components of Cawthorne-Cooksey and Norre exercises was applied. Dizziness Handicap Inventory (DHI) and visual analogue scale (VAS) were completed three times (at the beginning, end of the second week and end of the treatment). Data for 112 patients in the first stage and 93 patients in the second stage were evaluated because of insufficient compliance of the other patients. The mean DHI score was decreased from 50.42 +/- 24.12 points to 21.21 +/- 15.97 points (p < 0.001) at the end of first two weeks, and to 19.93 +/- 19.33 points at the end of the whole treatment. The mean VAS score was decreased from 5.87 +/- 2.27 to 2.02 +/- 1.75 (p < 0.001) at the end of second week, and to 1.51 +/- 1.29 at the end of eighth week. In respect to both VAS and DHI scores, improvement was noted in 67 patients (77.4%). Age, gender and disability level had no predictive value about therapy outcome. There was a fast recovery in the supervised exercise session, whereas there was no significant difference in the home exercise session. These findings suggest that either supervised exercise is better than home exercise or that 10 supervised sessions are sufficient to get the end result.

  9. Enlarged Vestibular Aqueducts and Childhood Hearing Loss

    Science.gov (United States)

    ... Infections, and Deafness Enlarged Vestibular Aqueducts and Childhood Hearing Loss On this page: What are vestibular aqueducts? How ... How are enlarged vestibular aqueducts related to childhood hearing loss? Research suggests that most children with enlarged vestibular ...

  10. The vestibular system: balancing more than just the body.

    Science.gov (United States)

    Lopez, Christophe

    2016-02-01

    The review presents a selection of recent studies in the field of vestibular neuroscience, including how vestibular stimulation modulates space and body perception. Recent neuroimaging studies identified the operculo-insular/retroinsular cortex as the core vestibular cortex and showed how it is reorganized after vestibular dysfunctions. Subliminal galvanic vestibular stimulation (GVS) induces long-term reduction of hemispatial neglect and improves vertical perception in stroke patients, but the underlying mechanisms remain to be identified. Healthy volunteer research suggests that GVS and caloric vestibular stimulation (CVS) modulate visual and somatosensory processing and that beneficial effects of GVS/CVS in stroke patients are not limited to merely rebalancing brain hemispheric activity. Another mechanism would be that GVS/CVS anchors the self to the body, thus promoting an egocentric frame of reference. In addition to 'balancing the body', the vestibular cortical network contributes to modulate space, body and self-awareness. Emerging evidence suggests that the vestibular network expands into dimensions of emotion processing, mental health, and social cognition. Here, the importance of connecting vestibular physiology, affective neuroscience, and social neuroscience to better understand the psychological aspects of vertigo in otoneurology is discussed.

  11. Bedside examination for vestibular screening in occupational medicine

    Directory of Open Access Journals (Sweden)

    Ewa Zamysłowska-Szmytke

    2015-04-01

    Full Text Available Objectives: The aim of the study was to assess the usefulness of bedside examination for screening of vestibular and balance system for occupational medicine purposes. Study group comprised 165 patients referred to Audiology and Phoniatric Clinic due to vestibular and/or balance problems. Caloric canal paresis of 19% was the cut off value to divide patients into 43 caloric-positive vestibular subjects and 122 caloric-negative patients. The latter group comprised 79 subjects revealing abnormalities of videonystagmographic (VNG oculomotor tests (central group and 43 subjects with normal VNG. Material and Methods: Vestibular and balance symptoms were collected. Five tests were included to bedside examination: Romberg and Unterberger tests, Head Impulse Test (HIT, Dynamic Visual Acuity (DVA and gaze nystagmus assessment. Results: Vestibular and balance symptoms were reported by 82% of vestibular, 73% of central and 40% of VNG-normal patients. Thirteen out of 18 VNG-normal but symptomatic subjects (73% had abnormal tests in clinical assessment. The sensitivity of bedside test set for vestibular pathology was 88% as compared to caloric test and 68% for central pathology as compared to VNG oculomotor tests. Conclusions: The combination of 5 bedside tests reveal satisfactory sensitivity to detect vestibular abnormalities. Bedside examination abnormalities are highly correlated with vestibular/balance symptoms, regardless the normal results of VNG. Thus, this method should be recommended for occupational medicine purposes.

  12. Bedside examination for vestibular screening in occupational medicine.

    Science.gov (United States)

    Zamysłowska-Szmytke, Ewa; Szostek-Rogula, Sylwia; Śliwińska-Kowalska, Mariola

    2015-01-01

    The aim of the study was to assess the usefulness of bedside examination for screening of vestibular and balance system for occupational medicine purposes. Study group comprised 165 patients referred to Audiology and Phoniatric Clinic due to vestibular and/or balance problems. Caloric canal paresis of 19% was the cut off value to divide patients into 43 caloric-positive vestibular subjects and 122 caloric-negative patients. The latter group comprised 79 subjects revealing abnormalities of videonystagmographic (VNG) oculomotor tests (central group) and 43 subjects with normal VNG. Vestibular and balance symptoms were collected. Five tests were included to bedside examination: Romberg and Unterberger tests, Head Impulse Test (HIT), Dynamic Visual Acuity (DVA) and gaze nystagmus assessment. Vestibular and balance symptoms were reported by 82% of vestibular, 73% of central and 40% of VNG-normal patients. Thirteen out of 18 VNG-normal but symptomatic subjects (73%) had abnormal tests in clinical assessment. The sensitivity of bedside test set for vestibular pathology was 88% as compared to caloric test and 68% for central pathology as compared to VNG oculomotor tests. The combination of 5 bedside tests reveal satisfactory sensitivity to detect vestibular abnormalities. Bedside examination abnormalities are highly correlated with vestibular/balance symptoms, regardless the normal results of VNG. Thus, this method should be recommended for occupational medicine purposes. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  13. Evaluation and treatment of vestibular dysfunction in children.

    Science.gov (United States)

    Rine, Rose Marie; Wiener-Vacher, Sylvette

    2013-01-01

    The effect of vestibular dysfunction since birth is more debilitating than that attained later in life, and unlike adults, children with vestibular dysfunction since or shortly after birth do not recover function without intervention. The purpose of this report is to provide an overview of the etiology of vestibular dysfunction in children as well as the related impairments, and to describe testing methods and evidence based interventions to ameliorate the vestibular related impairments in children. In recent years, investigations have revealed that vestibular dysfunction is more common in children than previously thought, with consequent impairments in motor development, balance and reading abilities. The dysfunction may be due to central or peripheral lesions, each with distinct presentation of symptoms and test results. Common etiologies and clinical presentation of vestibular dysfunction in children are reviewed; appropriate screening and diagnostic techniques and efficacious medical and rehabilitation interventions are presented. Despite advances in clinical and diagnostic testing of vestibular function in children and infants, testing of vestibular function is not typically done. Comprehensive testing of signs and symptoms is critical for diagnosis and implementation of appropriate interventions.

  14. Otolith-Canal Convergence in Vestibular Nuclei Neurons

    Science.gov (United States)

    Dickman, J. David

    1996-01-01

    During manned spaceflight, acute vestibular disturbances often occur, leading to physical duress and a loss of performance. Vestibular adaptation to the weightless environment follows within two to three days yet the mechanisms responsible for the disturbance and subsequent adaptation are still unknown In order to understand vestibular system function in space and normal earth conditions the basic physiological mechanisms of vestibular information co coding must be determined. Information processing regarding head movement and head position with respect to gravity takes place in the vestibular nuclei neurons that receive signals From the semicircular canals and otolith organs in the vestibular labyrinth. These neurons must synthesize the information into a coded output signal that provides for the head and eye movement reflexes as well as the conscious perception of the body in three-dimensional space The current investigation will for the first time. determine how the vestibular nuclei neurons quantitatively synthesize afferent information from the different linear and angular acceleration receptors in the vestibular labyrinths into an integrated output signal. During the second year of funding, progress on the current project has been focused on the anatomical orientation of semicircular canals and the spatial orientation of the innervating afferent responses. This information is necessary in order to understand how vestibular nuclei neurons process the incoming afferent spatial signals particularly with the convergent otolith afferent signals that are also spatially distributed Since information from the vestibular nuclei is presented to different brain regions associated with differing reflexive and sensory functions it is important to understand the computational mechanisms used by vestibular neurons to produce the appropriate output signal.

  15. [Therapy of vestibular vertigo].

    Science.gov (United States)

    Hamann, K F

    1993-05-01

    The non-surgical treatment of vestibular disorders must be based on current knowledge of vestibular pathophysiology. It is generally accepted that after vestibular lesions a self-repair mechanism exists that allows a more or less complete recovery. In cases of persisting vestibular complaints the physician's duty consists in stimulation of these pre-existing mechanisms. This can be done by physical exercises, as has been recommended since the work of Cawthorne and Cooksey in 1946. This concept is meanwhile supported by modern neurophysiological research. This article describes a short training program consisting of exercises for fixation during rotations, smooth pursuit, optokinetic nystagmus and motor learning mechanisms. Physical exercises can be reinforced by nootropic drugs.

  16. Angiogenesis in vestibular schwannomas

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Werther, Kim; Nalla, Amarnadh

    2010-01-01

    Vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) are potent mediators of tumor angiogenesis. It has been demonstrated that vestibular schwannoma VEGF expression correlates with tumor growth pattern, whereas knowledge on the expression of MMPs is lacking. This study...

  17. Valuing preferences over stormwater management outcomes including improved hydrologic function

    Science.gov (United States)

    LondoñO Cadavid, Catalina; Ando, Amy W.

    2013-07-01

    Stormwater runoff causes environmental problems such as flooding, soil erosion, and water pollution. Conventional stormwater management has focused primarily on flood reduction, while a new generation of decentralized stormwater solutions yields ancillary benefits such as healthier aquatic habitat, improved surface water quality, and increased water table recharge. Previous research has estimated values for flood reduction from stormwater management, but no estimates exist for the willingness to pay (WTP) for some of the other environmental benefits of alternative approaches to stormwater control. This paper uses a choice experiment survey of households in Champaign-Urbana, Illinois, to estimate the values of several attributes of stormwater management outcomes. We analyzed data from 131 surveyed households in randomly selected neighborhoods. We find that people value reduced basement flooding more than reductions in yard or street flooding, but WTP for basement flood reduction in the area only exists if individuals are currently experiencing significant flooding themselves. Citizens value both improved water quality and improved hydrologic function and aquatic habitat from runoff reduction. Thus, widespread investment in low impact development stormwater solutions could have very large total benefits, and stormwater managers should be wary of policies and infrastructure plans that reduce flooding at the expense of water quality and aquatic habitat.

  18. Deregulated genes in sporadic vestibular schwannomas

    DEFF Research Database (Denmark)

    Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea; Stangerup, Sven-Eric

    2010-01-01

    In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology.......In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology....

  19. Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders

    OpenAIRE

    Manso, Andréa; Ganança, Mauricio Malavasi; Caovilla, Heloisa Helena

    2016-01-01

    ABSTRACT INTRODUCTION: Visual stimuli can induce vestibular adaptation and recovery of body balance. OBJECTIVE: To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. METHODS: Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD) (experimental...

  20. Analysis of Hearing Preservation and Facial Nerve Function for Patients Undergoing Vestibular Schwannoma Surgery: The Middle Cranial Fossa Approach versus the Retrosigmoid Approach - Personal Experience and Literature Review

    National Research Council Canada - National Science Library

    Rabelo de Freitas, Marcos; Russo, Alessandra; Sequino, Giuliano; Piccirillo, Enrico; Sanna, Mario

    2012-01-01

    ...) or the retrosigmoid approach (RSA). Materials and Methods: A review of the medical records of patients diagnosed with vestibular schwannoma who underwent surgical tumor removal in a single reference center via the MCFA or the RSA between January 1988...

  1. Effects of Vestibular Loss on Orthostatic Responses to Tilts in the Pitch Plane

    Science.gov (United States)

    Wood, Scott J.; Serrador, Jorge M.; Black, F. Owen; Rupert,Angus H.; Schlegel, Todd T.

    2004-01-01

    The purpose of this study was to determine the extent to which vestibular loss might impair orthostatic responses to passive tilts in the pitch plane in human subjects. Data were obtained from six subjects having chronic bilateral vestibular loss and six healthy individuals matched for age, gender, and body mass index. Vestibular loss was assessed with a comprehensive battery including dynamic posturography, vestibulo-ocular and optokinetic reflexes, vestibular evoked myogenic potentials, and ocular counterrolling. Head up tilt tests were conducted using a motorized two-axis table that allowed subjects to be tilted in the pitch plane from either a supine or prone body orientation at a slow rate (8 deg/s). The sessions consisted of three tilts, each consisting of20 min rest in a horizontal position, tilt to 80 deg upright for 10 min, and then return to the horizontal position for 5 min. The tilts were performed in darkness (supine and prone) or in light (supine only). Background music was used to mask auditory orientation cues. Autonomic measurements included beat-to-beat recordings of blood pressure (Finapres), heart rate (ECG), cerebral blood flow velocity in the middle cerebral artery (transcranial Doppler), end tidal CO2, respiratory rate and volume (Respritrace), and stroke volume (impedance cardiography). For both patients and control subjects, cerebral blood flow appeared to exhibit the most rapid adjustment following transient changes in posture. Outside of a greater cerebral hypoperfusion in patients during the later stages of tilt, responses did not differ dramatically between the vestibular loss and control subjects, or between tilts performed in light and dark room conditions. Thus, with the 'exception of cerebrovascular regulation, we conclude that orthostatic responses during slow postural tilts are not substantially impaired in humans following chronic loss of vestibular function, a result that might reflect compensation by nonvisual graviceptor

  2. Vestibular Dysfunctions in Cochlear Implant Patients; A Vestibular Evoked Myogenic Potential Study

    Directory of Open Access Journals (Sweden)

    Masoud Motasaddi Zarandy

    2011-12-01

    Full Text Available Background and Aim: Vestibular evoked myogenic potential in response to click or short tone burst stimuli have been used as a clinical test for distinguish saccule and inferior vestibular nerve diseases. Different studies show that cochlear implant could have inverse effects on vestibular structures. We aimed to investigate vestibular evoked myogenic potential in unilateral cochlear implanted individuals in compare to normal individuals.Methods: Thirty-three unilateral cochlear implanted patients (mean age 19.96 years and 30 normal hearing individuals (mean age 24-27 years as control group were enrolled in this cross- sectional study. Absolute latencies and amplitudes of myogenic potential responses were measured and compared in both groups.Results: Myogenic potential recorded in both ears of all controls were normal. No response could be recorded in 16 patients (48.48% from both ears. In three patients, responses were recorded in both ears though the amplitude of waves was reduced in implanted ear. Unilateral response could be recorded in 14 patients only in their non-implanted ear.Conclusion: Vestibular evoked myogenic potential test is a useful tool for assessing saccular function in cochlear implant patients. Damages of osseous spiral lamina and basilar membrane after cochlear implantation could result in dysfunctions of vestibular organs specially saccule. It seems that saccule could be easily damaged after cochlear implantation. This would cause absence or reduced amplitudes in myogenic potential.

  3. State Anxiety Subjective Imbalance and Handicap in Vestibular Schwannoma.

    Science.gov (United States)

    Saman, Yougan; Mclellan, Lucie; Mckenna, Laurence; Dutia, Mayank B; Obholzer, Rupert; Libby, Gerald; Gleeson, Michael; Bamiou, Doris-Eva

    2016-01-01

    Evidence is emerging for a significant clinical and neuroanatomical relationship between balance and anxiety. Research has suggested a potentially priming effect with anxiety symptoms predicting a worsening of balance function in patients with underlying balance dysfunction. We propose to show that a vestibular stimulus is responsible for an increase in state anxiety, and there is a relationship between increased state anxiety and worsening balance function. (1) To quantify state anxiety following a vestibular stimulus in patients with a chronic vestibular deficit. (2) To determine if state anxiety during a vestibular stimulus would correlate with the severity of chronic balance symptoms and handicap. Two separate cohorts of vestibular schwannoma (VS) patients underwent vestibular tests (electronystagmography, cervical and ocular vestibular evoked myogenic potentials, and caloric responses) and questionnaire assessments [vertigo handicap questionnaire (VHQ), vertigo symptom scale (VSS), and state-trait anxiety inventory (STAIY)]. Fifteen post-resection VS patients, with complete unilateral vestibular deafferentation, were assessed at a minimum of 6 months after surgery in Experiment 1 (Aim 1). Forty-five patients with VS in situ formed the cohort for Experiment 2 (Aim 2). Experiment 1: VS subjects (N = 15) with a complete post-resection unilateral vestibular deafferentation completed a state anxiety questionnaire before caloric assessment and again afterward with the point of maximal vertigo as the reference (Aim 1). Experiment 2: state anxiety measured at the point of maximal vertigo following a caloric assessment was compared between two groups of patients with VS in situ presenting with balance symptoms (Group 1, N = 26) and without balance symptoms (Group 2, N = 11) (Aim 2). The presence of balance symptoms was defined as having a positive score on the VSS-VER. In Experiment 1, a significant difference (p handicap (p < 0.001). Anxiety

  4. Differential central projections of vestibular afferents in pigeons

    Science.gov (United States)

    Dickman, J. D.; Fang, Q.

    1996-01-01

    The question of whether a differential distribution of vestibular afferent information to central nuclear neurons is present in pigeons was studied using neural tracer compounds. Discrete tracing of afferent fibers innervating the individual semicircular canal and otolith organs was produced by sectioning individual branches of the vestibular nerve that innervate the different receptor organs and applying crystals of horseradish peroxidase, or a horseradish peroxidase/cholera toxin mixture, or a biocytin compound for neuronal uptake and transport. Afferent fibers and their terminal distributions within the brainstem and cerebellum were visualized subsequently. Discrete areas in the pigeon central nervous system that receive primary vestibular input include the superior, dorsal lateral, ventral lateral, medial, descending, and tangential vestibular nuclei; the A and B groups; the intermediate, medial, and lateral cerebellar nuclei; and the nodulus, the uvula, and the paraflocculus. Generally, the vertical canal afferents projected heavily to medial regions in the superior and descending vestibular nuclei as well as the A group. Vertical canal projections to the medial and lateral vestibular nuclei were observed but were less prominent. Horizontal canal projections to the superior and descending vestibular nuclei were much more centrally located than those of the vertical canals. A more substantial projection to the medial and lateral vestibular nuclei was seen with horizontal canal afferents compared to vertical canal fibers. Afferents innervating the utricle and saccule terminated generally in the lateral regions of all vestibular nuclei in areas that were separate from the projections of the semicircular canals. In addition, utricular fibers projected to regions in the vestibular nuclei that overlapped with the horizontal semicircular canal terminal fields, whereas saccular afferents projected to regions that received vertical canal fiber terminations. Lagenar

  5. Clinical value of 4-hour delayed gadolinium-Enhanced 3D FLAIR MR Images in Acute Vestibular Neuritis.

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    Byun, Hayoung; Chung, Jae Ho; Lee, Seung Hwan; Park, Chul Won; Park, Dong Woo; Kim, Tae Yoon

    2018-01-13

    To investigate the clinical significance of 4-hour delayed-enhanced 3.0 Tesla three-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) magnetic resonance (MR) imaging in acute vestibular neuritis. A prospective observational study. Twenty-nine vestibular neuritis patients were enrolled between January 2017 and June 2017. Vestibular function tests, comprising the caloric and video head impulse tests and vestibular-evoked myogenic potential measurements, were performed. Precontrast, 10-minute, and 4-hour delayed-enhanced 3D-FLAIR MR images using double-dose IV gadolinium were obtained. After laterality and extent of inner ear enhancement were defined, the patients were divided into groups based on the patterns of enhancement, and clinical parameters were analyzed according to the groups. Twenty patients (20 of 29, 69.0%) had obviously asymmetric enhancement of the affected inner ear structures on 4-hour delayed images, whereas only three patients (10.3%) had marked enhancement on 10-minute delayed images. The duration of spontaneous nystagmus (DurSN) was significantly longer in the patients with enhancement, especially with enhancement of the whole inner ear, including the vestibule and semicircular canals (P < 0.033). Spontaneous nystagmus resolved within 12 days in patients without laterality of enhancement, and within 16 days in ipsilesional enhancement confined to the inner auditory canal and fundus. Other results of vestibular function tests did not reveal any significant associations with MR enhancement. Contrast enhancement of the vestibular nerve and inner ear structures can be identified on 4-hour delayed-enhanced 3T 3D-FLAIR MR images in acute vestibular neuritis. The extent of inner ear enhancement may be associated with the DurSN. IV. Laryngoscope, 2017. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

  6. Eye Movements as Indicators of Vestibular Dysfunction.

    Science.gov (United States)

    Menshikova, Galina Ya; Kovalev, Artem I; Klimova, Oxana A; Chernorizov, Alexander M

    2015-01-01

    Virtual reality technologies are in wide use in sport psychology. An advantage of this kind of technology is the possibility to assess sportspeople's readiness to perform complex movements. This study is aimed at developing a method for the evaluation of vestibular function disturbances in young skaters. Such disturbances may occur while skaters are performing rotation movements. To achieve this goal, we induced a vection illusion, accompanied by virtual environment rotation in a CAVE virtual reality system. Vestibular disturbances were tested for two groups-professional skaters and people who had very little or no skating experience. The quantitative evaluation of vestibular dysfunction was based on eye movement characteristics, which were recorded in subjects experiencing a vection illusion. © The Author(s) 2015.

  7. Vestibular Compensation in Unilateral Patients Often Causes Both Gain and Time Constant Asymmetries in The VOR

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    Mina eRanjbaran

    2016-03-01

    Full Text Available The vestibulo-ocular reflex (VOR is essential in our daily life to stabilize retinal images during head movements. Balanced vestibular functionality secures optimal reflex performance which can be distorted in case of peripheral vestibular lesions. Luckily, vestibular compensation in different neuronal sites restores VOR function to some extent over time. Studying vestibular compensation gives insight into the possible mechanisms for plasticity in the brain.In this work, novel experimental analysis tools are employed to reevaluate the VOR characteristics following unilateral vestibular lesions and compensation. Our results suggest that following vestibular lesions, asymmetric performance of the VOR is not only limited to its gain. Vestibular compensation also causes asymmetric dynamics, i.e. different time constants for the VOR during leftward or rightward passive head rotation. Potential mechanisms for these experimental observations are provided using simulation studies.

  8. Visual dependency and dizziness after vestibular neuritis.

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    Sian Cousins

    Full Text Available Symptomatic recovery after acute vestibular neuritis (VN is variable, with around 50% of patients reporting long term vestibular symptoms; hence, it is essential to identify factors related to poor clinical outcome. Here we investigated whether excessive reliance on visual input for spatial orientation (visual dependence was associated with long term vestibular symptoms following acute VN. Twenty-eight patients with VN and 25 normal control subjects were included. Patients were enrolled at least 6 months after acute illness. Recovery status was not a criterion for study entry, allowing recruitment of patients with a full range of persistent symptoms. We measured visual dependence with a laptop-based Rod-and-Disk Test and severity of symptoms with the Dizziness Handicap Inventory (DHI. The third of patients showing the worst clinical outcomes (mean DHI score 36-80 had significantly greater visual dependence than normal subjects (6.35° error vs. 3.39° respectively, p = 0.03. Asymptomatic patients and those with minor residual symptoms did not differ from controls. Visual dependence was associated with high levels of persistent vestibular symptoms after acute VN. Over-reliance on visual information for spatial orientation is one characteristic of poorly recovered vestibular neuritis patients. The finding may be clinically useful given that visual dependence may be modified through rehabilitation desensitization techniques.

  9. Congenital and compensated vestibular dysfunction in childhood: an overlooked entity.

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    Weiss, Avery H; Phillips, James O

    2006-07-01

    We report five children with previously unrecognized vestibular dysfunction detected by clinical examination and confirmed by quantitative vestibular testing. Patient 1 presented with fluctuating visual acuity and intermittent nystagmus. Patient 2 had congenital hearing loss associated with imbalance, delayed motor development, and cyclic vomiting. Patient 3 had neurotrophic keratitis with an intermittent head tilt, imbalance, and motor delays. Patient 4 showed ataxia and eye movement abnormalities following traumatic brain injury and had reading difficulties. Patient 5 had episodic vertigo and eye movement abnormalities from infancy. Clinical vestibular testing emphasized spontaneous nystagmus, rapid head thrust, and assessment of post-rotatory nystagmus. Quantitative vestibular testing included the sinusoidal chair rotation and velocity step tests, measurement of dynamic visual acuity, post-head-shake nystagmus, and computerized platform posturography. Pediatric neurologists encounter children with congenital and compensated vestibular dysfunction, which can be recognized on the basis of relevant history and clinical abnormalities of the ocular-ocular reflex.

  10. Synaptic plasticity in the medial vestibular nuclei: role of glutamate receptors and retrograde messengers in rat brainstem slices.

    Science.gov (United States)

    Grassi, S; Pettorossi, V E

    2001-08-01

    potentiation. Finally the fifth part suggests the possible functional significance of different action times of the two retrograde messengers and metabotropic glutamate receptors, which are involved in mediating the presynaptic mechanism sustaining vestibular long-term potentiation.

  11. Systematic review of vestibular disorders related to human immunodeficiency virus and acquired immunodeficiency syndrome.

    Science.gov (United States)

    Heinze, B; Swanepoel, D W; Hofmeyr, L M

    2011-09-01

    Disorders of the auditory and vestibular system are often associated with human immunodeficiency virus infection and acquired immunodeficiency syndrome. However, the extent and nature of these vestibular manifestations are unclear. To systematically review the current peer-reviewed literature on vestibular manifestations and pathology related to human immunodeficiency virus and acquired immunodeficiency syndrome. Systematic review of peer-reviewed articles related to vestibular findings in individuals with human immunodeficiency virus infection and acquired immunodeficiency syndrome. Several electronic databases were searched. We identified 442 records, reduced to 210 after excluding duplicates and reviews. These were reviewed for relevance to the scope of the study. We identified only 13 reports investigating vestibular functioning and pathology in individuals affected by human immunodeficiency virus and acquired immunodeficiency syndrome. This condition can affect both the peripheral and central vestibular system, irrespective of age and viral disease stage. Peripheral vestibular involvement may affect up to 50 per cent of patients, and central vestibular involvement may be even more prevalent. Post-mortem studies suggest direct involvement of the entire vestibular system, while opportunistic infections such as oto- and neurosyphilis and encephalitis cause secondary vestibular dysfunction resulting in vertigo, dizziness and imbalance. Patients with human immunodeficiency virus and acquired immunodeficiency syndrome should routinely be monitored for vestibular involvement, to minimise functional limitations of quality of life.

  12. STATE ANXIETY, SUBJECTIVE IMBALANCE AND HANDICAP IN VESTIBULAR SCHWANNOMA

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    Yougan Saman

    2016-07-01

    Full Text Available ABSTRACTEvidence is emerging of a significant clinical and neuro-anatomical relationship between balance and anxiety. Research has suggested a potentially priming effect with anxiety symptoms predicting a worsening of balance function in patients with underlying balance dysfunction. We propose to show that a vestibular stimulus is responsible for an increase in state anxiety and there is a relationship between increased state anxiety and worsening balance function. Aims1.To quantify state anxiety following a vestibular stimulus in patients with a chronic vestibular deficit.2.To determine if state anxiety during a vestibular stimulus would correlate with the severity of chronic balance symptoms and handicap. MethodsTwo separate cohorts Vestibular Schwannoma (VS patients underwent vestibular tests (electronystagmography, cervical and ocular vestibular evoked myogenic potentials and caloric responses and questionnaire assessment (Vertigo handicap Questionnaire, Vertigo Symptom Scale, State Trait Anxiety InventoryFifteen post resection Vestibular schwannoma patients, with complete unilateral vestibular deafferentation, were assessed at a minimum of 6 months after surgery in Experiment 1 (Aim 1. Forty-five patients with VS in-situ and with preserved vestibular function formed the cohort for Experiment 2 (Aim 2. Experiment 1: VS subjects (N=15 with a complete post-resection unilateral vestibular deafferentation completed a State anxiety questionnaire before caloric assessment and again afterwards with the point of maximal vertigo as the reference (Aim 1. Experiment 2: State anxiety measured at the point of maximal vertigo following a caloric assessment was compared between two groups of presenting with balance symptoms (Group 1 N=26 and without balance symptoms (Group 2 N=11 (Aim 2. The presence of balance symptoms was defined as having a positive score on the VSS-VER.ResultsIn experiment 1, a significant difference (p<0.01 was found when comparing

  13. Significant vestibular system impairment is common in a cohort of elderly patients referred for assessment of falls risk.

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    Jacobson, Gary P; McCaslin, Devin L; Grantham, Sarah L; Piker, Erin G

    2008-01-01

    Falls in elderly patients are associated with morbidity, mortality, and cost to the healthcare system. The development of falls risk assessment programs have represented a method of responding to what is known about injurious falls. The multidimensional assessments involve the comparison against normative data of a patient's performance on metrics known to influence the likelihood of future falls. The factors assessed usually include falls and medication history, measures of mentation, depression, orthostatic hypotension, simple or choice reaction time, gait stability, postural stability, and the integrity of the patient's vision, somesthetic, and vestibular senses. This investigation was conducted to measure the proportion of patients referred for falls risk assessment who have evidence of vestibular system impairment. Qualitative, retrospective review of data collected from 2003 to 2007. The cohort was 185 consecutive patients referred for multidimensional assessments of falls risk. Patients underwent quantitative assessments of peripheral and central vestibular system function consisting of electro- or videonystagmography (i.e., ENG/VNG), and sinusoidal harmonic acceleration testing. Results of these tests were compared to normative data. We found that 73% of the sample who underwent vestibular system assessment had quantitative evidence of either peripheral or central vestibular system impairment. Our results suggest that quantitative assessments of the vestibulo-ocular reflex should be conducted on patients who are evaluated for falls risk. These examinations should include at least caloric testing and, where available, rotational testing.

  14. Vestibular rehabilitation following mild traumatic brain injury.

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    Gurley, James M; Hujsak, Bryan D; Kelly, Jennifer L

    2013-01-01

    Vertigo, dizziness, and imbalance are a symptom complex that is commonly found following concussion. Early metabolic changes following concussion may lead to worsening of the injury and symptoms in individuals not properly managed from the outset. When symptoms do not recover spontaneously, skilled vestibular rehabilitation can be an effective modality in an attempt to normalize the individual's vestibular responses. The purpose of this review is to appraise the current and accepted methods available to the skilled clinician in quantifying and treating vestibular dysfunction following concussion. Incidence and prognostic indicators will be reviewed along with common barriers to recovery. Vestibular Rehabilitation following concussion utilizes similar tools and techniques employed when treating those solely with peripheral pathology. The clinician must not only have a solid understanding of when and why certain exercises are required, but also be willing to accept that less exercise may be indicated in this population. As injury to the system following mild traumatic brain injury can include both peripheral and central structures, the duration of therapy and the time to recovery may be prolonged. Co-morbidities including cognitive and behavioral issues, visual-perceptual dysfunction, metabolic dysfunction, and autonomic dysfunction may hamper the effectiveness of the traditional Vestibular Rehabilitation approach. As successful treatment does not occur in a vacuum, working closely with other disciplines well versed in treating these co-morbid issues will help the individual to obtain optimal recovery. Vestibular Rehabilitation is an effective modality for managing dizziness, vertigo, and imbalance following concussion. Careful consideration of the acuity of the injury, along with effective management of co-morbid conditions will optimize the result.

  15. The challenge of vestibular migraine.

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    Sargent, Eric W

    2013-10-01

    Migraine is a common illness and migraine-related dizziness occurs in up to 3% of the population. Because the diagnosis is controversial and may be difficult, many patients go undiagnosed and untreated. This review summarizes current understanding of the taxonomy and diagnosis of vestibular migraine, the relation of vestibular migraine to labyrinthine disease, and the treatment of the condition in adults and children. The categories of migraine accepted by the International Headache Society do not reflect the complex presentations of patients suspected of having vestibular migraine. In clinical practice and research, criteria are increasingly accepted that divide patients suspected of vestibular migraine into 'definite vestibular migraine' and 'probable vestibular migraine.' Because vertigo itself may trigger migraine, patients with vestibular migraine should be suspected of having vestibular end-organ disease until proven otherwise. Treatment remains controversial because of a notable lack of randomized controlled studies of vestibular migraine treatment. For now, the best strategy for the treatment of suspected vestibular migraine patients is dietary/lifestyle modification, antinausea/antiemetics for acute vertigo, and preventive medication for patients who have continued disruptive symptoms. Patients with vestibular migraine should be monitored regularly for the development of latent audiovestibular end-organ disease.

  16. Intrinsic membrane properties of central vestibular neurons in rodents.

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    Eugène, Daniel; Idoux, Erwin; Beraneck, Mathieu; Moore, L E; Vidal, Pierre-Paul

    2011-05-01

    Numerous studies in rodents have shown that the functional efficacy of several neurotransmitter receptors and the intrinsic membrane excitability of central vestibular neurons, as well as the organization of synaptic connections within and between vestibular nuclei can be modified during postnatal development, after a lesion of peripheral vestibular organs or in vestibular-deficient mutant animals. This review mainly focuses on the intrinsic membrane properties of neurons of the medial vestibular nuclei of rodents, their postnatal maturation, and changes following experimental or congenital alterations in vestibular inputs. It also presents the concomitant modifications in the distribution of these neurons into different neuron types, which has been based on their membrane properties in relation to their anatomical, biochemical, or functional properties. The main points discussed in this review are that (1) the intrinsic membrane properties can be used to distinguish between two dominant types of neurons, (2) the system remains plastic throughout the whole life of the animal, and finally, (3) the intracellular calcium concentration has a major effect on the intrinsic membrane properties of central vestibular neurons.

  17. Behavioural and objective vestibular assessment in persons with osteoporosis and osteopenia: a preliminary investigation.

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    Gargeshwari, Aditi; Jha, Raghav Hira; Singh, Niraj Kumar; Kumar, Prawin

    2017-09-21

    Calcium is vital for the functioning of the inner ear hair cells as well as for the neurotransmitter release that triggers the generation of a nerve impulse. A reduction in calcium level could therefore impair the peripheric vestibular functioning. However, the outcome of balance assessment has rarely been explored in cases with osteopenia and osteoporosis, the medical conditions associated with reduction in calcium levels. The present study aimed to investigate the impact of osteopenia and osteoporosis on the outcomes of behavioural and objective vestibular assessment tests. The study included 12 individuals each in the healthy control group and osteopenia group, and 11 individuals were included in the osteoporosis group. The groups were divided based on the findings of bone mineral density. All the participants underwent behavioural tests (Fukuda stepping, tandem gait and subjective visual vertical) and objective assessment using cervical and ocular vestibular evoked myogenic potentials. A significantly higher proportion of the individuals in the two clinical groups' demonstrated abnormal results on the behavioural balance assessment tests (p<0.05) than the control group. However, there was no significant difference in latencies or amplitude of cervical vestibular evoked myogenic potential and oVEMP between the groups. The proportion of individuals with absence of ocular vestibular evoked myogenic potential was significantly higher in the osteoporosis group than the other two groups (p<0.05). The findings of the present study confirm the presence of balance-related deficits in individuals with osteopenia and osteoporosis. Hence the clinical evaluations should include balance assessment as a mandatory aspect of the overall audiological assessment of individuals with osteopenia and osteoporosis. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  18. The molecular biology and novel treatments of vestibular schwannomas.

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    Fong, Brendan; Barkhoudarian, Garni; Pezeshkian, Patrick; Parsa, Andrew T; Gopen, Quinton; Yang, Isaac

    2011-11-01

    Vestibular schwannomas are histopathologically benign tumors arising from the Schwann cell sheath surrounding the vestibular branch of cranial nerve VIII and are related to the NF2 gene and its product merlin. Merlin acts as a tumor suppressor and as a mediator of contact inhibition. Thus, deficiencies in both NF2 genes lead to vestibular schwannoma development. Recently, there have been major advances in our knowledge of the molecular biology of vestibular schwannomas as well as the development of novel therapies for its treatment. In this article the authors comprehensively review the recent advances in the molecular biology and characterization of vestibular schwannomas as well as the development of modern treatments for vestibular schwannoma. For instance, merlin is involved with a number of receptors including the CD44 receptor, EGFR, and signaling pathways, such as the Ras/raf pathway and the canonical Wnt pathway. Recently, merlin was also shown to interact in the nucleus with E3 ubiquitin ligase CRL4(DCAF1). A greater understanding of the molecular mechanisms behind vestibular schwannoma tumorigenesis has begun to yield novel therapies. Some authors have shown that Avastin induces regression of progressive schwannomas by over 40% and improves hearing. An inhibitor of VEGF synthesis, PTC299, is currently in Phase II trials as a potential agent to treat vestibular schwannoma. Furthermore, in vitro studies have shown that trastuzumab (an ERBB2 inhibitor) reduces vestibular schwannoma cell proliferation. With further research it may be possible to significantly reduce morbidity and mortality rates by decreasing tumor burden, tumor volume, hearing loss, and cranial nerve deficits seen in vestibular schwannomas.

  19. Vestibular animal models: contributions to understanding physiology and disease

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    Straka, Hans; Zwergal, Andreas; Cullen, Kathleen E.

    2016-01-01

    Our knowledge of the vestibular sensory system, its functional significance for gaze and posture stabilization, and its capability to ensure accurate spatial orientation perception and spatial navigation has greatly benefitted from experimental approaches using a variety of vertebrate species. This review summarizes the attempts to establish the roles of semicircular canal and otolith endorgans in these functions followed by an overview of the most relevant fields of vestibular research inclu...

  20. Caracterização clínica de idosos com disfunção vestibular crônica Clinical evaluation of elderly people with chronic vestibular disorder

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    Juliana Maria Gazzola

    2006-08-01

    Full Text Available A tontura de origem vestibular é comum entre idosos. OBJETIVO: Caracterizar idosos com disfunção vestibular crônica em relação aos dados sociodemográficos, clínico-funcionais e otoneurológicos. MATERIAL E MÉTODO: Estudo de casos que incluiu 120 idosos com disfunção vestibular crônica. Foram realizadas análises descritivas simples. RESULTADOS: A 5,77±amostra apresentou maioria feminina (68,3%, com média etária de 73,40 1,84±anos. O número médio de doenças associadas ao quadro vestibular foi de 3,83 e o número médio de medicamentos foi de 3,86±2,27. O exame vestibular evidenciou vestibulopatia periférica deficitária unilateral (29,8% e as hipóteses diagnósticas prevalentes foram labirintopatia metabólica (40,0% e vertigem posicional paroxística benigna (36,7%. Para 52 (43,3% pacientes, a tontura começou há mais de 5 anos. Em relação à queda, 64 idosos (53,3% apresentaram pelo menos uma queda no último ano e 35 (29,2% referiram quedas recorrentes. CONCLUSÕES: A amostra foi representada por maioria feminina e média etária elevada, com doenças associadas ao quadro vestibular e polifarmacoterapia. As vestibulopatias e a topografia mais freqüentes foram, respectivamente, labirintopatia metabólica e vascular e síndrome periférica deficitária unilateral. A tontura é uma condição crônica e a associação de vestibulopatias é comum. A ocorrência de quedas é prevalente na população de idosos com disfunção vestibular crônica.Dizziness is common among the elderly. AIM: To characterize social, demographic, clinical, functional and otoneurological data in elderly patients with chronic vestibular disorder. METHOD: A sequential study of 120 patients with chronic vestibular disorder. Simple descriptive analyses were undertaken. RESULTS: Most of the patients were female (68.3% with a mean age of 73.40±5.77 years. The average number of illnesses associated with the vestibular disorder was 3.83±1.84; the

  1. Effects of vibrotactile vestibular substitution on vestibular rehabilitation - preliminary study,

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    Cibele Brugnera

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Some patients with severe impairment of body balance do not obtain adequate improvement from vestibular rehabilitation (VR. OBJECTIVE: To evaluate the effectiveness of Vertiguard(tm biofeedback equipment as a sensory substitution (SS of the vestibular system in patients who did not obtain sufficient improvement from VR. METHODS: This was a randomized prospective clinical study. Thirteen patients without satisfactory response to conventional VR were randomized into a study group (SG, which received the vibrotactile stimulus from Vertiguard(tm for ten days, and a control group (CG, which used equipment without the stimulus. For pre- and post-treatment assessment, the Sensory Organization Test (SOT protocol of the Computerized Dynamic Posturography (CDP and two scales of balance self-perception, Activities-specific Balance Confidence (ABC and Dizziness Handicap Inventory (DHI, were used. RESULTS: After treatment, only the SG showed statistically significant improvement in C5 (p = 0.007 and C6 (p = 0.01. On the ABC scale, there was a significant difference in the SG (p= 0.04. The DHI showed a significant difference in CG and SG with regard to the physical aspect, and only in the SG for the functional aspect (p = 0.04. CONCLUSION: The present findings show that sensory substitution using the vibrotactile stimulus of the Vertiguard(tm system helped with the integration of neural networks involved in maintaining posture, improving the strategies used in the recovery of body balance.

  2. Effects of vibrotactile vestibular substitution on vestibular rehabilitation - preliminary study.

    Science.gov (United States)

    Brugnera, Cibele; Bittar, Roseli Saraiva Moreira; Greters, Mário Edvin; Basta, Dietmar

    2015-01-01

    Some patients with severe impairment of body balance do not obtain adequate improvement from vestibular rehabilitation (VR). To evaluate the effectiveness of Vertiguard™ biofeedback equipment as a sensory substitution (SS) of the vestibular system in patients who did not obtain sufficient improvement from VR. This was a randomized prospective clinical study. Thirteen patients without satisfactory response to conventional VR were randomized into a study group (SG), which received the vibrotactile stimulus from Vertiguard™ for ten days, and a control group (CG), which used equipment without the stimulus. For pre- and post-treatment assessment, the Sensory Organization Test (SOT) protocol of the Computerized Dynamic Posturography (CDP) and two scales of balance self-perception, Activities-specific Balance Confidence (ABC) and Dizziness Handicap Inventory (DHI), were used. After treatment, only the SG showed statistically significant improvement in C5 (p=0.007) and C6 (p=0.01). On the ABC scale, there was a significant difference in the SG (p=0.04). The DHI showed a significant difference in CG and SG with regard to the physical aspect, and only in the SG for the functional aspect (p=0.04). The present findings show that sensory substitution using the vibrotactile stimulus of the Vertiguard™ system helped with the integration of neural networks involved in maintaining posture, improving the strategies used in the recovery of body balance. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  3. Artificial balance: restoration of the vestibulo-ocular reflex in humans with a prototype vestibular neuroprosthesis.

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    Perez Fornos, Angelica; Guinand, Nils; van de Berg, Raymond; Stokroos, Robert; Micera, Silvestro; Kingma, Herman; Pelizzone, Marco; Guyot, Jean-Philippe

    2014-01-01

    The vestibular system plays a crucial role in the multisensory control of balance. When vestibular function is lost, essential tasks such as postural control, gaze stabilization, and spatial orientation are limited and the quality of life of patients is significantly impaired. Currently, there is no effective treatment for bilateral vestibular deficits. Research efforts both in animals and humans during the last decade set a solid background to the concept of using electrical stimulation to restore vestibular function. Still, the potential clinical benefit of a vestibular neuroprosthesis has to be demonstrated to pave the way for a translation into clinical trials. An important parameter for the assessment of vestibular function is the vestibulo-ocular reflex (VOR), the primary mechanism responsible for maintaining the perception of a stable visual environment while moving. Here we show that the VOR can be artificially restored in humans using motion-controlled, amplitude modulated electrical stimulation of the ampullary branches of the vestibular nerve. Three patients received a vestibular neuroprosthesis prototype, consisting of a modified cochlear implant providing vestibular electrodes. Significantly higher VOR responses were observed when the prototype was turned ON. Furthermore, VOR responses increased significantly as the intensity of the stimulation increased, reaching on average 79% of those measured in healthy volunteers in the same experimental conditions. These results constitute a fundamental milestone and allow us to envision for the first time clinically useful rehabilitation of patients with bilateral vestibular loss.

  4. Artificial balance: restoration of the vestibulo-ocular reflex in humans with a prototype vestibular neuroprosthesis

    Directory of Open Access Journals (Sweden)

    Angelica ePerez Fornos

    2014-04-01

    Full Text Available The vestibular system plays a crucial role in the multisensory control of balance. When vestibular function is lost, essential tasks such as postural control, gaze stabilization, and spatial orientation are limited and the quality of life of patients is significantly impaired. Currently there is no effective treatment for bilateral vestibular deficits. Research efforts both in animals and humans during the last decade set a solid background to the concept of using electrical stimulation to restore vestibular function. Still, the potential clinical benefit of a vestibular neuroprosthesis has to be demonstrated to pave the way for a translation into clinical trials. An important parameter for the assessment of vestibular function is the Vestibulo-Ocular Reflex (VOR, the primary mechanism responsible for maintaining the perception of a stable visual environment while moving. Here we show that the VOR can be artificially restored in humans using motion-controlled, amplitude modulated electrical stimulation of the ampullary branches of the vestibular nerve. Three patients received a vestibular neuroprosthesis prototype, consisting of a modified cochlear implant providing vestibular electrodes. Significantly higher VOR responses were observed when the prototype was turned ON. Furthermore, VOR responses increased significantly as the intensity of the stimulation increased, reaching on average 79% of those measured in healthy volunteers in the same experimental conditions. These results constitute a fundamental milestone and allow us to envision for the first time clinically useful rehabilitation of patients with bilateral vestibular loss.

  5. Vestibular Modulation of Sympathetic Nerve Activity to Muscle and Skin in Humans.

    Science.gov (United States)

    Hammam, Elie; Macefield, Vaughan G

    2017-01-01

    We review the existence of vestibulosympathetic reflexes in humans. While several methods to activate the human vestibular apparatus have been used, galvanic vestibular stimulation (GVS) is a means of selectively modulating vestibular afferent activity via electrodes over the mastoid processes, causing robust vestibular illusions of side-to-side movement. Sinusoidal GVS (sGVS) causes partial entrainment of sympathetic outflow to muscle and skin. Modulation of muscle sympathetic nerve activity (MSNA) from vestibular inputs competes with baroreceptor inputs, with stronger temporal coupling to the vestibular stimulus being observed at frequencies remote from the cardiac frequency; "super entrainment" was observed in some individuals. Low-frequency (vestibular stimulation. However, it should be noted that GVS influences the firing of afferents from the entire vestibular apparatus, including the semicircular canals. To identify the specific source of vestibular input responsible for the generation of vestibulosympathetic reflexes, we used low-frequency (vestibular modulation of MSNA are very similar. Moreover, that modulation of MSNA occurs at accelerations well below levels at which subjects are able to perceive any motion indicates that, like vestibulospinal control of posture, the vestibular system contributes to the control of blood pressure through potent reflexes in humans.

  6. New Insights into Pathophysiology of Vestibular Migraine

    Science.gov (United States)

    Espinosa-Sanchez, Juan M.; Lopez-Escamez, Jose A.

    2015-01-01

    Vestibular migraine (VM) is a common disorder in which genetic, epigenetic, and environmental factors probably contribute to its development. The pathophysiology of VM is unknown; nevertheless in the last few years, several studies are contributing to understand the neurophysiological pathways involved in VM. The current hypotheses are mostly based on the knowledge of migraine itself. The evidence of trigeminal innervation of the labyrinth vessels and the localization of vasoactive neuropeptides in the perivascular afferent terminals of these trigeminal fibers support the involvement of the trigemino-vascular system. The neurogenic inflammation triggered by activation of the trigeminal-vestibulocochlear reflex, with the subsequent inner ear plasma protein extravasation and the release of inflammatory mediators, can contribute to a sustained activation and sensitization of the trigeminal primary afferent neurons explaining VM symptoms. The reciprocal connections between brainstem vestibular nuclei and the structures that modulate trigeminal nociceptive inputs (rostral ventromedial medulla, ventrolateral periaqueductal gray, locus coeruleus, and nucleus raphe magnus) are critical to understand the pathophysiology of VM. Although cortical spreading depression can affect cortical areas involved in processing vestibular information, functional neuroimaging techniques suggest a dysmodulation in the multimodal sensory integration and processing of vestibular and nociceptive information, resulting from a vestibulo-thalamo-cortical dysfunction, as the pathogenic mechanism underlying VM. The elevated prevalence of VM suggests that multiple functional variants may confer a genetic susceptibility leading to a dysregulation of excitatory–inhibitory balance in brain structures involved in the processing of sensory information, vestibular inputs, and pain. The interactions among several functional and structural neural networks could explain the pathogenic mechanisms of VM

  7. New insights into pathophysiology of vestibular migraine

    Directory of Open Access Journals (Sweden)

    Juan Manuel Espinosa-Sanchez

    2015-02-01

    Full Text Available Vestibular migraine (VM is a common disorder in which genetic, epigenetic and environmental factors probably contribute to its development. The pathophysiology of VM is unknown; nevertheless in the last few years, several studies are contributing to understand the neurophysiological pathways involved in VM. The current hypotheses are mostly based on the knowledge of migraine itself. The evidence of trigeminal innervation of the labyrinth vessels and the localization of vasoactive neuropeptides in the perivascular afferent terminals of these trigeminal fibers support the involvement of the trigemino-vascular system. The neurogenic inflammation triggered by activation of the trigeminal-vestibulocochlear reflex, with the subsequent inner ear plasma protein extravasation and the release of inflammatory mediators, can contribute to a sustained activation and sensitization of the trigeminal primary afferent neurons explaining VM symptoms. The reciprocal connections between brainstem vestibular nuclei and the structures that modulate trigeminal nociceptive inputs (rostral ventromedial medulla, ventrolateral periaqueductal grey, locus coeruleus and nucleus raphe magnus are critical to understand the pathophysiology of VM. Although cortical spreading depression can affect cortical areas involved in processing vestibular information, functional neuroimaging techniques suggest a dysmodulation in the multimodal sensory integration and processing of vestibular and nociceptive information, resulting from a vestibulo-thalamo-cortical dysfunction, as the pathogenic mechanism underlying VM. The elevated prevalence of VM suggests that multiple functional variants may confer a genetic susceptibility leading to a dysregulation of excitatory-inhibitory balance in brain structures involved in the processing of sensory information, vestibular inputs and pain. The interactions among several functional and structural neural networks could explain the pathogenic

  8. The vestibular body: Vestibular contributions to bodily representations.

    Science.gov (United States)

    Ferrè, Elisa Raffaella; Haggard, Patrick

    2016-01-01

    Vestibular signals are integrated with signals from other sensory modalities. This convergence could reflect an important mechanism for maintaining the perception of the body. Here we review the current literature in order to develop a framework for understanding how the vestibular system contributes to body representation. According to recent models, we distinguish between three processes for body representation, and we look at whether vestibular signals might influence each process. These are (i) somatosensation, the primary sensory processing of somatic stimuli, (ii) somatoperception, the processes of constructing percepts and experiences of somatic objects and events and (iii) somatorepresentation, the knowledge about the body as a physical object in the world. Vestibular signals appear to contribute to all three levels in this model of body processing. Thus, the traditional view of the vestibular system as a low-level, dedicated orienting module tends to underestimate the pervasive role of vestibular input in bodily self-awareness.

  9. Betahistine treatment in managing vertigo and improving vestibular compensation: clarification.

    Science.gov (United States)

    Lacour, Michel

    2013-01-01

    Betahistine dihydrochloride (betahistine) is currently used in the management of vertigo and vestibular pathologies with different aetiologies. The main goal of this review is to clarify the mechanisms of action of this drug, responsible for the symptomatic relief of vertigo and the improvement of vestibular compensation. The review starts with a brief summary recalling the role of histamine as a neuromodulator/neurotransmitter in the control of the vestibular functions, and the role of the histaminergic system in vestibular compensation. Then are presented data recorded in animal models demonstrating that betahistine efficacy can be explained by mechanisms targeting the histamine receptors (HRs) at three different levels: the vascular tree, with an increase of cochlear and vestibular blood flow involving the H1R; the central nervous system, with an increase of histamine turnover implicating the H3R, and the peripheral labyrinth, with a decrease of vestibular input implying the H3R/H4R. Clinical data from vestibular loss patients show the impact of betahistine treatment for the long-term control of vertigo, improvement of balance and quality of life that can be explained by these mechanisms of action. However, two conditions, at least, are required for reaching the betahistine therapeutic effect: the dose and the duration of treatment. Experimental and clinical data supporting these requirements are exposed in the last part of this review.

  10. Treating vertigo with vestibular rehabilitation: results in 155 patients.

    Science.gov (United States)

    Bittar, R S M; Pedalini, M E B; Lorenzi, M C; Formigoni, L G

    2002-01-01

    Balance is fundamental to our daily activities and the vestibular system, together with vision and proprioceptive functions, are the main structures involved in this process. Dizziness is the main clinical manifestation of malfunction of these systems. The mechanisms of vestibular compensation are one of the most studied aspects since they play an important role in the patient's everyday activities. In this retrospective description of a series of cases the authors present their results in 155 patients that underwent a program of vestibular rehabilitation (VR). The program, first described by Cawthorne and Coosey, is based on mechanisms of potentiation of the cervico-ocular reflex and substitution of the lost vestibular cues for visual and somatosensory cues. The results were satisfactory (remission or partial cure) in 75.5% of the patients, with an average treatment time of up to 2 months and 5 or fewer sessions performed in most of the cases. The results were somewhat inferior in those cases in which a central vestibular lesion or more than one etiologic factor was present. The results of a subgroup of elderly patients (age > 65 years) were similar to those of the total number of studied subjects. Vestibular rehabilitation, associated to the specific etiological treatment, appears to be a very useful tool in the management of patients suffering from dizziness of all ages, although different clinical responses to the therapy may vary according to the presence of a central or a peripheral vestibular lesion or multiple etiological factors.

  11. Galvanic vestibular stimulation improves the results of vestibular rehabilitation.

    Science.gov (United States)

    Carmona, Sergio; Ferrero, Antonela; Pianetti, Guillermina; Escolá, Natalia; Arteaga, María Victoria; Frankel, Lilian

    2011-09-01

    Here, we present findings from a three-step investigation of the effect of galvanic vestibular stimulation (GVS) in normal subjects and in subjects undergoing vestibular rehabilitation (VR). In an initial study, we examined the body sway of 10 normal subjects after one minute of 2 mA GVS. The effect of the stimulation lasted for at least 20 minutes in all subjects and up to two hours in 70% of the subjects. We then compared a group of patients who received conventional VR (40 patients) with a group that received a combination of VR and GVS. Results suggest a significant improvement in the second group. Finally, we attempted to establish the optimal number of GVS sessions and to rule out a placebo effect. Fifteen patients received "systematic" GVS: five sessions, once a week. Five patients received "nonsystematic" galvanic stimulation in a sham protocol, which included two stimulations of the clavicle. These data were analyzed with Fisher's exact test and indicated that the best results were obtained after three sessions of GVS and no placebo effect was observed. © 2011 New York Academy of Sciences.

  12. Vestibular rehabilitation following surgical repair for Superior Canal Dehiscence Syndrome: A complicated case report.

    Science.gov (United States)

    Carender, Wendy J; Grzesiak, Melissa

    2018-02-01

    Superior Canal Dehiscence Syndrome (SCDS) causes auditory and vestibular symptoms. Following surgical repair of the dehiscence, patients often experience dizziness and imbalance. This case report describes a postoperative vestibular exercise program, focusing on the principles of central compensation and habituation, and how it was modified for a patient with delayed progress secondary to strabismus and visual vertigo. A 63-year-old male with history of strabismus eye surgery, right hearing loss, aural fullness, and sensitivity to loud sounds was referred for vestibular rehabilitation (VR). He was seen for one preoperative and six postoperative PT visits over eight months. Outcome measures two weeks postoperative were as follows: Dizziness Handicap Inventory (DHI) 38/100; Timed Up & Go (TUG) 9.92 seconds; Dynamic Gait Index (DGI) 16/24; and a 3-line difference in Dynamic Visual Acuity (DVA). Improved outcomes at discharge included: DHI 18/100; TUG 6.87 seconds; DGI 23/24; and 1-line difference in DVA. He was able to return to work and previously enjoyed recreational activities. Postoperative vestibular rehabilitation programs are functionally and symptomatically beneficial following surgical repair for SCDS. Deviations from expected recovery should be addressed to achieve optimal outcomes as demonstrated in this complicated case report.

  13. Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis

    Science.gov (United States)

    ... vestibular schwannoma is key to preventing its serious consequences. There are three options for managing a vestibular ... Disorders Balance Problems and Disorders - National Institute on Aging Enlarged Vestibular Aqueducts and Childhood Hearing Loss Genetics ...

  14. Latent nystagmus: vestibular nystagmus with a twist.

    Science.gov (United States)

    Brodsky, Michael C; Tusa, Ronald J

    2004-02-01

    Latent nystagmus is a horizontal binocular oscillation that is evoked by unequal visual input to the 2 eyes. It develops primarily in humans with congenital esotropia. To investigate the interrelationship between latent and peripheral vestibular nystagmus and their corollary neuroanatomical pathways. Examination of subcortical neuroanatomical pathways producing latent nystagmus and review of the neurophysiological mechanisms by which they become activated in congenital esotropia. The vestibular nucleus presides over motion input from the eyes and labyrinths. Latent nystagmus corresponds to the optokinetic component of ocular rotation that is driven monocularly by nasal optic flow during a turning movement of the body in lateral-eyed animals. Congenital esotropia alters visual pathway development from the visual cortex to subcortical centers that project to the vestibular nucleus, allowing this primitive subcortical motion detection system to generate latent nystagmus under conditions of monocular fixation. Latent nystagmus is the ocular counterpart of peripheral vestibular nystagmus. Its clinical expression in humans proclaims the evolutionary function of the eyes as sensory balance organs.

  15. New perspectives on vestibular evoked myogenic potentials.

    Science.gov (United States)

    Rosengren, Sally M; Kingma, Herman

    2013-02-01

    Although the vestibular evoked myogenic potential (VEMP) measured from the cervical muscles (cVEMP, cervical VEMP) is well described and has documented clinical utility, its analogue recorded from the extraocular muscles (oVEMP, ocular VEMP) has been described only recently and is currently emerging as an additional test of otolith function. This review will, therefore, summarize recent developments in VEMP research with a focus on the oVEMP. Recent studies suggest that the oVEMP is produced by otolith afferents in the superior vestibular nerve division, whereas the cVEMP evoked by sound is thought to be an inferior vestibular nerve reflex. Correspondingly, the oVEMP correlates better with caloric and subjective visual vertical tests than sound-cVEMPs. cVEMPs are more complicated than often thought, as shown by the presence of crossed responses and conflicting results of recent vibration studies. Altered inner ear mechanics produced by the vestibular diseases superior semicircular canal dehiscence and Ménière's disease lead to changes in the preferred frequency of the oVEMP and cVEMP. The oVEMP provides complementary diagnostic information to the cVEMP and is likely to be a useful addition to the diagnostic test battery in neuro-otology.

  16. Effects of Vestibular Rehabilitation Interventions in the Elderly with Chronic Unilateral Vestibular Hypofunction

    Science.gov (United States)

    Bayat, Arash; Saki, Nader

    2017-01-01

    Introduction: Although vestibular rehabilitation therapy (VRT) methods are relatively popular in treating patients with body balance deficits of vestibular origin, only limited studies have been conducted into customized exercises for unilateral vestibular hypofunction (UVH). Furthermore, very little evidence is available on the outcomes of VRT in the elderly population with chronic UVH. Materials and Methods: A total of 21 patients, aged 61 to 74 years, with UVH participated in this study. The dizziness handicap inventory (DHI) was performed immediately before, and 2 and 8 weeks after treatment. Results: All patients showed a reduction in DHI scores during the study. The average decrease in DHI score was 25.98 points after 2 weeks’ intervention (P0.05). There were no relationships between the scores and gender. Conclusion: Our study demonstrates that VRT is an effective method for the management of elderly patients with UVH, and shows maximal effect on functional aspects. PMID:28819615

  17. Characteristics and clinical applications of ocular vestibular evoked myogenic potentials.

    Science.gov (United States)

    Kantner, C; Gürkov, R

    2012-12-01

    Recently, ocular vestibular evoked myogenic potentials (oVEMPs) have been described and added to the neuro-otologic test battery as a new measure for the vestibulo-ocular reflex. oVEMPs represent extraocular muscle activity in response to otolith stimulation e.g. by air-conducted sound or bone-conducted vibration. In response to vestibular stimulation, electromyographic activity of the extraocular muscles can be recorded by means of surface electrodes placed beneath the contralateral eye. oVEMPs are likely to reflect predominantly utricular function, while the widely established cervical vestibular evoked myogenic potentials (cVEMPs) assess saccular function. Thus, measuring oVEMPs and cVEMPs in addition to caloric and head impulse testing provides further evaluation of the vestibular system and enables quick and cost-effective assessment of otolith function. This review summarizes the neurophysiological properties of oVEMPs, gives recommendations for recording conditions and discusses oVEMP alterations in various disorders of the vestibular system. With increasing insight into oVEMP characteristics in vestibular disorders, e.g. Menière's disease and superior semicircular canal dehiscence syndrome, oVEMPs are becoming a promising new diagnostic tool for evaluating utricular function. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Vestibular syndrome: a change in internal spatial representation.

    Science.gov (United States)

    Borel, L; Lopez, C; Péruch, P; Lacour, M

    2008-12-01

    The vestibular system contributes to a wide range of functions from reflexes to spatial representation. This paper reviews behavioral, perceptive, and cognitive data that highlight the role of changes in internal spatial representation on the vestibular syndrome. Firstly, we review how visual vertical perception and postural orientation depend on multiple reference frames and multisensory integration and how reference frames are selected according to the status of the peripheral vestibular system (i.e., unilateral or bilateral hyporeflexia), the environmental constraints (i.e., sensory cues), and the postural constraints (i.e., balance control). We show how changes in reference frames are able to modify vestibular lesion-induced postural and locomotor deficits and propose that fast changes in reference frame may be considered as fast-adaptive processes after vestibular loss. Secondly, we review data dealing with the influence of vestibular loss on higher levels of internal representation sustaining spatial orientation and navigation. Particular emphasis is placed on spatial performance according to task complexity (i.e., the required level of spatial knowledge) and to the sensory cues available to define the position and orientation within the environment (i.e., real navigation in darkness or visual virtual navigation without any actual self-motion). We suggest that vestibular signals are necessary for other sensory cues to be properly integrated and that vestibular cues are involved in extrapersonal space representation. In this respect, vestibular-induced changes would be based on a dynamic mental representation of space that is continuously updated and that supports fast-adaptive processes.

  19. Vestibular Aqueduct Midpoint Width and Hearing Loss in Patients With an Enlarged Vestibular Aqueduct.

    Science.gov (United States)

    Ascha, Mustafa S; Manzoor, Nauman; Gupta, Amit; Semaan, Maroun; Megerian, Cliff; Otteson, Todd D

    2017-06-01

    Elucidating the relationship between vestibular aqueduct size and hearing loss progression may inform the prognosis and counseling of patients who have an enlarged vestibular aqueduct (EVA). To examine the association between vestibular aqueduct size and repeated measures of hearing loss. For this retrospective medical record review, 52 patients with a diagnosis of hearing loss and radiologic diagnosis of EVA according to the Valvassori criterion were included. All available speech reception threshold and word recognition score data was retrieved; mixed-effects models were constructed where vestibular aqueduct size, age at diagnosis of hearing loss, and time since diagnosis of hearing loss were used to predict repeated measures of hearing ability. This study was performed at an academic tertiary care center. Variable vestibular aqueduct size, age at first audiogram, length of time after first audiogram. Speech reception threshold (dB) and word recognition score (%) during routine audiogram. Overall, 52 patients were identified (29 females [56%] and 23 males [44%]; median age at all recorded audiograms, 7.8 years) with a total of 74 ears affected by EVA. Median (range) vestibular aqueduct size was 2.15 (1.5-5.9) mm, and a median (range) of 5 (1-18) tests were available for each patient. Each millimeter increase in vestibular aqueduct size above 1.5 mm was associated with an increase of 17.5 dB in speech reception threshold (95% CI, 7.2 to 27.9 dB) and a decrease of 21% in word recognition score (95% CI, -33.3 to -8.0 dB). For each extra year after a patient's first audiogram, there was an increase of 1.5 dB in speech recognition threshold (95% CI, 0.22 to 3.0 dB) and a decrease of 1.7% in word recognition score (95% CI, -3.08 to -0.22 dB). Hearing loss in patients with an EVA is likely influenced by vestibular aqueduct midpoint width. When considering hearing loss prognosis, vestibular aqueduct midpoint width may be useful for the clinician who counsels patients

  20. Drug therapy for peripheral vestibular vertigo

    Directory of Open Access Journals (Sweden)

    L. M. Antonenko

    2017-01-01

    Full Text Available The choice of effective treatments for vestibular vertigo is one of the important problems, by taking into account the high prevalence of peripheral vestibular diseases. Different drugs, such as vestibular suppressants for the relief of acute vertigo attacks and vestibular compensation stimulants for rehabilitation treatment, are used to treat vestibular vertigo. Drug therapy in combination with vestibular exercises is effective in patients with vestibular neuronitis, Meniere's disease, so is that with therapeutic maneuvers in patients with benign paroxysmal positional vertigo. The high therapeutic efficacy and safety of betahistines permit their extensive use for the treatment of various vestibular disorders.

  1. [Neuronal plasticity of otolith-related vestibular system].

    Science.gov (United States)

    Lai, Suk-King; Lai, Chun-Hong; Zhang, Fu-Xing; Ma, Chun-Wai; Shum, Daisy K Y; Chan, Ying-Shing

    2008-12-01

    This review focuses on our effort in addressing the development and lesion-induced plasticity of the gravity sensing system. After severance of sensory input from one inner ear, there is a bilateral imbalance in response dynamics and spatial coding behavior between neuronal subpopulations on the two sides. These data provide the basis for deranged spatial coding and motor deficits accompanying unilateral labyrinthectomy. Recent studies have also confirmed that both glutamate receptors and neurotrophin receptors within the bilateral vestibular nuclei are implicated in the plasticity during vestibular compensation and development. Changes in plasticity not only provide insight into the formation of a spatial map and recovery of vestibular function but also on the design of drugs for therapeutic strategies applicable to infants or vestibular disorders such as vertigo and dizziness.

  2. [Presbyastasis and application of vestibular rehabilitation in geriatrics].

    Science.gov (United States)

    Costa de Araujo, P; Demanez, L; Lechien, J; Bauvir, P; Petermans, J

    2011-03-01

    Balance disorders can have a major functional impact among the elderly. The main risk is falling. Three elements are implicated in the loss of balance: vision, proprioception and the vestibular system. This article will discuss mainly vestibular damage and its implications. The assessment of balance disorders, particularly in geriatric patients, is based on validated scales composed of several items. These provide scores and are based on the results of chronometric measurements. They can be useful for the application of Vestibular Rehabilitation (VR), a technique improving the adaptation and autonomy of these patients. Vestibular rehabilitation is therefore part of an overall support, the goal of therapy being to improve daily life and to reduce the risk of falls.

  3. Vestibular rehabilitation: clinical benefits to patients with Parkinson's disease.

    Science.gov (United States)

    Zeigelboim, Bianca Simone; Klagenberg, Karlin Fabianne; Teive, Hélio A Ghizoni; Munhoz, Renato Puppi; Martins-Bassetto, Jackeline

    2009-06-01

    To evaluate the effectiveness of the vestibular rehabilitation (VR) exercises by means of an assessment before and after the application of the Brazilian version of the Dizziness Handicap Inventory (DHI) questionnaire. Twelve patients were studied, the following procedures were carried out: anamnesis, otorhinolaryngological and vestibular evaluation, and the application of the DHI before and after the VR. Clinically resting tremors and subjective postural instability were the motor complaints most frequently associated with complaints of vertigo in 12 cases (100%); in the vestibular exam, all the patients presented abnormalities, frequently from the uni and bilateral peripheral vestibular deficiency syndromes in 10 cases (83.3%); there was significant improvement in the physical, functional and emotional aspects of the DHI after the completion of the VR. The VR following the Cawthorne and Cooksey protocol were shown to be useful in managing subjective complaints of several aspects evaluated in this protocol.

  4. Effect of Enzogenol® Supplementation on Cognitive, Executive, and Vestibular/Balance Functioning in Chronic Phase of Concussion.

    Science.gov (United States)

    Walter, A; Finelli, K; Bai, X; Arnett, P; Bream, T; Seidenberg, P; Lynch, S; Johnson, B; Slobounov, S

    2017-01-01

    This study examined the feasibility of Enzogenol® as a potential treatment modality for concussed individuals with residual symptoms in the chronic phase. Forty-two student-athletes with history of sport-related concussion were enrolled, comparing Enzogenol® versus placebo. Testing was conducted using virtual reality (VR) and electroencephalography (EEG), with neuropsychological (NP) tasks primarily used to induce cognitive challenges. After six weeks, the Enzogenol® group showed enhanced frontal-midline theta, and decreased parietal theta power, indicating reduced mental fatigue. Subjects enrolled in the Enzogenol® group also self-reported reduced mental fatigue and sleep problems. This suggests that Enzogenol® has the potential to improve brain functioning in the chronic phase of concussion.

  5. Detection of isolated covert saccades with the video head impulse test in peripheral vestibular disorders.

    Science.gov (United States)

    Blödow, Alexander; Pannasch, Sebastian; Walther, Leif Erik

    2013-08-01

    The function of the semicircular canal receptors and the pathway of the vestibulo-ocular-reflex (VOR) can be diagnosed with the clinical head impulse test (cHIT). Recently, the video head impulse test (vHIT) has been introduced but so far there is little clinical experience with the vHIT in patients with peripheral vestibular disorders. The aim of the study was to investigate the horizontal VOR (hVOR) by means of vHIT in peripheral vestibular disorders. Using the vHIT, we examined the hVOR in a group of 117 patients and a control group of 20 healthy subjects. The group of patients included vestibular neuritis (VN) (n=52), vestibular schwannoma (VS) (n=31), Ménière's disease (MD) (n=22) and bilateral vestibulopathy (BV) (n=12). Normal hVOR gain was at 0.96 ± 0.08, while abnormal hVOR gain was at 0.44 ± 0.20 (79.1% of all cases). An abnormal vHIT was found in VN (94.2%), VS (61.3%), MD (54.5%) and BV (91.7%). Three conditions of refixation saccades occurred frequently in cases with abnormal hVOR: isolated covert saccades (13.7%), isolated overt saccades (34.3%) and the combination of overt and covert saccades (52.0%). The vHIT detects abnormal hVOR changes in the combination of gain assessment and refixation saccades. Since isolated covert saccades in hVOR changes can only be seen with vHIT, peripheral vestibular disorders are likely to be diagnosed incorrectly with the cHIT to a certain amount. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Treatment of Vestibular Dysfunction Using a Portable Stimulator

    Science.gov (United States)

    2017-04-01

    AWARD NUMBER: W81XWH-14-2-0012 TITLE: Treatment of Vestibular Dysfunction Using a Portable Stimulator PRINCIPAL INVESTIGATOR: Jorge M...PAGE UU 17 19b. TELEPHONE NUMBER (include area code) Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Treatment of Vestibular...noise over a 2week stimulation paradigm Significant Results of Year 3 1) Research flyers have been posted to aid in recruitment. Fourteen

  7. Neuropharmacological Targets for Drug Action in Vestibular Sensory Pathways

    OpenAIRE

    Lee, Choongheon; Jones, Timothy A

    2017-01-01

    The use of pharmacological agents is often the preferred approach to the management of vestibular dysfunction. In the vestibular sensory pathways, the sensory neuroepithelia are thought to be influenced by a diverse number of neuroactive substances that may act to enhance or inhibit the effect of the primary neurotransmitters [i.e., glutamate (Glu) and acetylcholine (ACh)] or alter their patterns of release. This review summarizes various efforts to identify drug targets including neurotransm...

  8. Gentamicin perfusion vestibular response and hearing loss.

    Science.gov (United States)

    Light, Joshua P; Silverstein, Herbert; Jackson, Lance E

    2003-03-01

    To compare hearing results as a function of vestibular ablation in the treatment of Ménière's Disease, using gentamicin perfusion. A retrospective review of patients with Ménière's Disease treated by gentamicin perfusion of the inner ear via the MicroWick device. A tertiary otologic referral center. The charts of patients treated with gentamicin perfusion via the MicroWick between the years 1998 and 2000 were reviewed. The results for patients with functional hearing in the affected ear were analyzed and were compared with the results in patients without functional hearing. Audiologic and vestibular test results as well as subjective symptoms. There were 45 patients who met the inclusion criteria. The averages for speech discrimination score and pure tone average before treatment were 92% and 38 dB, and after treatment were 82% and 47 dB. Patients were divided into two groups: Group 1 (20 patients), less than 75% ice air caloric reduced vestibular response (RVR); Group 2 (25 patients), those who reached greater than 75% ice air caloric RVR. There were 8 patients (17.6%) with persistent vertigo; 7 were from Group 1, and 1 was from Group 2, which was statistically significant (p = 0.007)wwww. The pure tone average dropped an average of 3 dB for Group 1 and 15 dB for Group 2. The difference in hearing loss between the two groups was statistically significant (p = 0.01). This study suggests that there is a correlation between the degree of vestibular ablation, the control of vertigo, and the risk of hearing loss. Patients with functional hearing seem to have a similar success rate for vertigo control, compared with patients who already had lost functional hearing before treatment. Future investigation may determine if less than 100% RVR, but greater than 75% RVR, is an alternative end point with adequate vertigo control and reduced risk of hearing loss.

  9. True incidence of vestibular schwannoma?

    DEFF Research Database (Denmark)

    Stangerup, Sven-Eric; Tos, Mirko; Thomsen, Jens

    2010-01-01

    The incidence of diagnosed sporadic unilateral vestibular schwannomas (VS) has increased, due primarily to more widespread access to magnetic resonance imaging.......The incidence of diagnosed sporadic unilateral vestibular schwannomas (VS) has increased, due primarily to more widespread access to magnetic resonance imaging....

  10. Hypervascular vestibular Schwannoma: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ja Young; Yu, In Kyu [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

    2014-11-15

    Most vestibular schwannoma is hypovascular with well known poor tumor staining in cerebral angiography. However, hypervascular vestibular schwannoma might be observed as a rare subtype with increased risk of bleeding during surgery. Multimodal imaging features which represent hypervascularity of the tumor can be observed in hypervascular vestibular schwannoma. Here we report a case of hypervascular vestibular schwannoma with brief literature review.

  11. Early and phasic cortical metabolic changes in vestibular neuritis onset.

    Directory of Open Access Journals (Sweden)

    Marco Alessandrini

    Full Text Available Functional brain activation studies described the presence of separate cortical areas responsible for central processing of peripheral vestibular information and reported their activation and interactions with other sensory modalities and the changes of this network associated to strategic peripheral or central vestibular lesions. It is already known that cortical changes induced by acute unilateral vestibular failure (UVF are various and undergo variations over time, revealing different cortical involved areas at the onset and recovery from symptoms. The present study aimed at reporting the earliest change in cortical metabolic activity during a paradigmatic form of UVF such as vestibular neuritis (VN, that is, a purely peripheral lesion of the vestibular system, that offers the opportunity to study the cortical response to altered vestibular processing. This research reports [(18F]fluorodeoxyglucose positron emission tomography brain scan data concerning the early cortical metabolic activity associated to symptoms onset in a group of eight patients suffering from VN. VN patients' cortical metabolic activity during the first two days from symptoms onset was compared to that recorded one month later and to a control healthy group. Beside the known cortical response in the sensorimotor network associated to vestibular deafferentation, we show for the first time the involvement of Entorhinal (BAs 28, 34 and Temporal (BA 38 cortices in early phases of symptomatology onset. We interpret these findings as the cortical counterparts of the attempt to reorient oneself in space counteracting the vertigo symptom (Bas 28, 34 and of the emotional response to the new pathologic condition (BA 38 respectively. These interpretations were further supported by changes in patients' subjective ratings in balance, anxiety, and depersonalization/derealization scores when tested at illness onset and one month later. The present findings contribute in expanding

  12. The Moving History of Vestibular Stimulation as a Therapeutic Intervention.

    Science.gov (United States)

    Grabherr, Luzia; Macauda, Gianluca; Lenggenhager, Bigna

    2015-01-01

    Although the discovery and understanding of the function of the vestibular system date back only to the 19th century, strategies that involve vestibular stimulation were used long before to calm, soothe and even cure people. While such stimulation was classically achieved with various motion devices, like Cox's chair or Hallaran's swing, the development of caloric and galvanic vestibular stimulation has opened up new possibilities in the 20th century. With the increasing knowledge and recognition of vestibular contributions to various perceptual, motor, cognitive, and emotional processes, vestibular stimulation has been suggested as a powerful and non-invasive treatment for a range of psychiatric, neurological and neurodevelopmental conditions. Yet, the therapeutic interventions were, and still are, often not hypothesis-driven as broader theories remain scarce and underlying neurophysiological mechanisms are often vague. We aim to critically review the literature on vestibular stimulation as a form of therapy in various selected disorders and present its successes, expectations, and drawbacks from a historical perspective.

  13. Optimal duration of therapy in the recovery period of vestibular diseases

    Directory of Open Access Journals (Sweden)

    M. V. Zamergrad

    2014-01-01

    Full Text Available Dizziness is a common symptom in neurological and general medical practice. In most cases it is caused by diseases of the central or peripheral vestibular system. The most common vestibular system diseases include benign paroxysmal postural vertigo, dizziness, Meniere's disease, vestibular neuronitis, and cerebrovascular diseases. One of the main treatments for the diseases accompanied by dizziness is vestibular rehabilitation that is a complex of exercises, the goal of which is to stimulate vestibular compensation. Adequate vestibular compensation allows a patient to get rid of dizziness and unsteadiness even though vestibular system injury is irreversible. Some medications are able to enhance the efficiency of vestibular rehabilitation. At the same time, the optimal duration of treatment for the most common vestibular disorders has not beenadequately explored. The paper gives the results of an observational program, whose purpose was to determine the optimal duration of vestibular rehabilitation in combination with the use of tanakan in patients with non-progressive unilateral peripheral vestibular disorder.Patients and methods. Data on 46 patients aged 19 to 70 years who underwent vestibular rehabilitation and took tanakan for vertigo caused by vestibular neuronitis (n = 44, labyrinthitis (n =1, or Ramsay Hunt syndrome (n = 1 were analyzed. All the patients were examined four times. The symptoms were recorded and the histories of disease were considered. The degree of vestibular disorders, including vertigo, was assessed when collecting complaints. The symptoms of vertigo were objectivized using its vertigo rating scale and five-point subjective rating scale for vertigo. All the patients underwent standard somatic and neurological examinations and videonystagmography. During the first visit after diagnosis, vestibular exercises were chosen for the patients and tanakan was used in a dose of 40 mg thrice daily to accelerate

  14. Cross-axis adaptation improves 3D vestibulo-ocular reflex alignment during chronic stimulation via a head-mounted multichannel vestibular prosthesis

    Science.gov (United States)

    Dai, Chenkai; Fridman, Gene Y.; Chiang, Bryce; Davidovics, Natan; Melvin, Thuy-Anh; Cullen, Kathleen E.; Della Santina, Charles C.

    2012-01-01

    By sensing three-dimensional (3D) head rotation and electrically stimulating the three ampullary branches of a vestibular nerve to encode head angular velocity, a multichannel vestibular prosthesis (MVP) can restore vestibular sensation to individuals disabled by loss of vestibular hair cell function. However, current spread to afferent fibers innervating non-targeted canals and otolith endorgans can distort the vestibular nerve activation pattern, causing misalignment between the perceived and actual axis of head rotation. We hypothesized that over time, central neural mechanisms can adapt to correct this misalignment. To test this, we rendered five chinchillas vestibular-deficient via bilateral gentamicin treatment and unilaterally implanted them with a head mounted MVP. Comparison of 3D angular vestibulo-ocular reflex (aVOR) responses during 2 Hz, 50°/s peak horizontal sinusoidal head rotations in darkness on the first, third and seventh days of continual MVP use revealed that eye responses about the intended axis remained stable (at about 70% of the normal gain) while misalignment improved significantly by the end of one week of prosthetic stimulation. A comparable time course of improvement was also observed for head rotations about the other two semicircular canal axes and at every stimulus frequency examined (0.2–5 Hz). In addition, the extent of disconjugacy between the two eyes progressively improved during the same time window. These results indicate that the central nervous system rapidly adapts to multichannel prosthetic vestibular stimulation to markedly improve 3D aVOR alignment within the first week after activation. Similar adaptive improvements are likely to occur in other species, including humans. PMID:21374081

  15. The Vestibular-Evoked Postural Response of Adolescents with Idiopathic Scoliosis Is Altered.

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    Jean-Philippe Pialasse

    Full Text Available Adolescent idiopathic scoliosis is a multifactorial disorder including neurological factors. A dysfunction of the sensorimotor networks processing vestibular information could be related to spine deformation. This study investigates whether feed-forward vestibulomotor control or sensory reweighting mechanisms are impaired in adolescent scoliosis patients. Vestibular evoked postural responses were obtained using galvanic vestibular stimulation while participants stood with their eyes closed and head facing forward. Lateral forces under each foot and lateral displacement of the upper body of adolescents with mild (n = 20 or severe (n = 16 spine deformation were compared to those of healthy control adolescents (n = 16. Adolescent idiopathic scoliosis patients demonstrated greater lateral displacement and net lateral forces than controls both during and immediately after vestibular stimulation. Altered sensory reweighting of vestibular and proprioceptive information changed balance control of AIS patients during and after vestibular stimulation. Therefore, scoliosis onset could be related to abnormal sensory reweighting, leading to altered sensorimotor processes.

  16. Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises

    OpenAIRE

    Esther Bernal Valls; Víctor Faus Cuñat; Raquel Bernal Valls

    2006-01-01

    El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.The use of exercises in the treatment of patients with vestibular deficits is increasing in a represent...

  17. Reabilitação vestibular no tratamento da tontura e do zumbido Vestibular rehabilitation in the treatment of dizziness and tinnitus

    Directory of Open Access Journals (Sweden)

    Bianca Simone Zeigelboim

    2008-01-01

    Brazilian population. METHODS: Six patients (two male and four female, with ages ranging from 43 to 70 years, were evaluated. The patients were submitted to the following procedures: anamnesis, otoscopy, vestibular evaluation through vectoelectronystagmography, and administration of the questionnaires, before and after vestibular rehabilitation, using the Cawthorne and Cooksey protocol. RESULTS: a regarding the most related complaints, imbalance when walking (83,3%, headache (66,6% and depression (66,6%, were observed; b in the vestibular exam all the patients showed alterations in the caloric test, and the most frequent syndrome was the irritative peripheral vestibular (83,3%; c two cases of irritative peripheral vestibular syndrome, two cases of irritative peripheral unilateral vestibular syndrome, one case of irritative peripheral bilateral vestibular syndrome and one case of peripheral deficient unilateral vestibular syndrome were verified in the vestibular exam; d in the administration of the DHI, an improvement in the functional and emotional aspects were observed, with the physical aspect remaining unchanged; e in the administration of the THI, an improvement was observed in all the aspects evaluated. CONCLUSION: The protocol of vestibular rehabilitation used in the study, promoted a decrease in tinnitus and dizziness, hence improving the quality of life of the patients.

  18. Evaluation of postural control in unilateral vestibular hypofunction.

    Science.gov (United States)

    Quitschal, Rafaela Maia; Fukunaga, Jackeline Yumi; Ganança, Maurício Malavasi; Caovilla, Heloísa Helena

    2014-01-01

    Patients with vestibular hypofunction, a typical finding in peripheral vestibular disorders, show body balance alterations. To evaluate the postural control of patients with vertigo and unilateral vestibular hypofunction. This is a clinical cross-sectional study. Twenty-five patients with vertigo and unilateral vestibular hypofunction and a homogeneous control group consisting of 32 healthy individuals were submitted to a neurotological evaluation including the Tetrax Interactive Balance System posturography in eight different sensory conditions. For different positions, vertiginous patients with unilateral vestibular hypofunction showed significantly higher values of general stability index, weight distribution index, right/left and tool/heel synchronizations, Fourier transformation index and fall index than controls. Increased values in the indices of weight distribution, right/left and tool/heel synchronizations, Fourier transformation and fall risk characterize the impairment of postural control in patients with vertigo and unilateral vestibular hypofunction. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  19. Evaluation of the chemical model of vestibular lesions induced by arsanilate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Vignaux, G. [INSERM, ERI27, Caen, F-14000 (France); Univ Caen, Caen, F-14000 (France); Chabbert, C.; Gaboyard-Niay, S.; Travo, C. [INSERM U1051, Institut des Neurosciences de Montpellier, Montpellier, F-34090,France (France); Machado, M.L. [INSERM, ERI27, Caen, F-14000 (France); Univ Caen, Caen, F-14000 (France); Denise, P. [INSERM, ERI27, Caen, F-14000 (France); Univ Caen, Caen, F-14000 (France); CHRU Caen, Explorations Fonctionnelles, Caen, F-14000 (France); Comoz, F. [CHRU Caen, Laboratoire d' anatomopathologie, Caen, F-14000 (France); Hitier, M. [CHRU Caen, Service d' Otorhinolaryngologie, Caen, F-14000,France (France); Landemore, G. [CHRU Caen, Laboratoire d' anatomopathologie, Caen, F-14000 (France); Philoxène, B. [INSERM, ERI27, Caen, F-14000 (France); Univ Caen, Caen, F-14000 (France); CHRU Caen, Explorations Fonctionnelles, Caen, F-14000 (France); Besnard, S., E-mail: besnard-s@phycog.org [INSERM, ERI27, Caen, F-14000 (France); Univ Caen, Caen, F-14000 (France); CHRU Caen, Explorations Fonctionnelles, Caen, F-14000 (France)

    2012-01-01

    Several animal models of vestibular deficits that mimic the human pathology phenotype have previously been developed to correlate the degree of vestibular injury to cognate vestibular deficits in a time-dependent manner. Sodium arsanilate is one of the most commonly used substances for chemical vestibular lesioning, but it is not well described in the literature. In the present study, we used histological and functional approaches to conduct a detailed exploration of the model of vestibular lesions induced by transtympanic injection of sodium arsanilate in rats. The arsanilate-induced damage was restricted to the vestibular sensory organs without affecting the external ear, the oropharynx, or Scarpa's ganglion. This finding strongly supports the absence of diffusion of arsanilate into the external ear or Eustachian tubes, or through the eighth cranial nerve sheath leading to the brainstem. One of the striking observations of the present study is the complete restructuring of the sensory epithelia into a non sensory epithelial monolayer observed at 3 months after arsanilate application. This atrophy resembles the monolayer epithelia observed postmortem in the vestibular epithelia of patients with a history of lesioned vestibular deficits such as labyrinthectomy, antibiotic treatment, vestibular neuritis, or Ménière's disease. In cases of Ménière's disease, aminoglycosides, and platinum-based chemotherapy, vestibular hair cells are destroyed, regardless of the physiopathological process, as reproduced with the arsanilate model of vestibular lesion. These observations, together with those presented in this study of arsanilate vestibular toxicity, suggest that this atrophy process relies on a common mechanism of degeneration of the sensory epithelia.

  20. The vestibular system and cognition.

    Science.gov (United States)

    Smith, Paul F

    2017-02-01

    The last year has seen a great deal of new information published relating vestibular dysfunction to cognitive impairment in humans, especially in the elderly. The objective of this review is to summarize and critically evaluate this new evidence in the context of the previous literature. This review will address the recent epidemiological/survey studies that link vestibular dysfunction with cognitive impairment in the elderly; recent clinical investigations into cognitive impairment in the context of vestibular dysfunction, both in the elderly and in the cases of otic capsule dehiscence and partial bilateral vestibulopathy; recent evidence that vestibular impairment is associated with hippocampal atrophy; and finally recent evidence relating to the hypothesis that vestibular dysfunction could be a risk factor for dementia. The main implication of these recent studies is that vestibular dysfunction, possibly of any type, may result in cognitive impairment, and this could be especially so for the elderly. Such symptoms will need to be considered in the treatment of patients with vestibular disorders.

  1. Frequency response of human vestibular reflexes characterized by stochastic stimuli.

    Science.gov (United States)

    Dakin, Christopher J; Son, Gregory M Lee; Inglis, J Timothy; Blouin, Jean-Sébastien

    2007-09-15

    Stochastic vestibular stimulation (SVS) can be used to study the postural responses to unpredictable vestibular perturbations. The present study seeks to determine if stochastic vestibular stimulation elicits lower limb muscular responses and to estimate the frequency characteristics of these vestibulo-motor responses in humans. Fourteen healthy subjects were exposed to unpredictable galvanic currents applied on their mastoid processes while quietly standing (+/-3 mA, 0-50 Hz). The current amplitude and stimulation configuration as well as the subject's head position relative to their feet were manipulated in order to determine that: (1) the muscle responses evoked by stochastic currents are dependent on the amplitude of the current, (2) the muscle responses evoked by stochastic currents are specific to the percutaneous stimulation of vestibular afferents and (3) the lower limb muscle responses exhibit polarity changes with different head positions as previously described for square-wave galvanic vestibular stimulation (GVS) pulses. Our results revealed significant coherence (between 0 and 20 Hz) and cumulant density functions (peak responses at 65 and 103 ms) between SVS and the lower limbs' postural muscle activity. The polarity of the cumulant density functions corresponded to that of the reflexes elicited by square-wave GVS pulses. The SVS-muscle activity coherence and time cumulant functions were modulated by current amplitude, electrode position and head orientation with respect to the subject's feet. These findings strongly support the vestibular origin of the lower limb muscles evoked by SVS. In addition, specific frequency bandwidths in the stochastic vestibular signal contributed to the early (12-20 Hz) and late components (2-10 Hz) of the SVS-evoked muscular responses. These frequency-dependent SVS-evoked muscle responses support the view that the biphasic muscle response is conveyed by two distinct physiological processes.

  2. Is the Headache in Patients with Vestibular Migraine Attenuated by Vestibular Rehabilitation?

    OpenAIRE

    Sugaya, Nagisa; ARAI, Miki; Goto, Fumiyuki

    2017-01-01

    Background Vestibular rehabilitation is the most effective treatment for dizziness due to vestibular dysfunction. Given the biological relationship between vestibular symptoms and headache, headache in patients with vestibular migraine (VM) could be improved by vestibular rehabilitation that leads to the improvement of dizziness. This study aimed to compare the effects of vestibular rehabilitation on headache and other outcomes relating to dizziness, and the psychological factors in patien...

  3. Spatial cognition, body representation and affective processes: the role of vestibular information beyond ocular reflexes and control of posture.

    Science.gov (United States)

    Mast, Fred W; Preuss, Nora; Hartmann, Matthias; Grabherr, Luzia

    2014-01-01

    A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: (1) Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths), body rotation (changing the input from the semicircular canals), in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. (2) Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. (3) Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are-at least in part-associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  4. Spatial Cognition, Body Representation and Affective Processes: The Role of Vestibular Information beyond Ocular Reflexes and Control of Posture

    Directory of Open Access Journals (Sweden)

    Fred W Mast

    2014-05-01

    Full Text Available A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: 1 Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths, body rotation (changing the input from the semicircular canals, in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. 2 Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. 3 Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are – at least in part – associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  5. The effect of changes in perilymphatic K+ on the vestibular evoked potential in the guinea pig

    NARCIS (Netherlands)

    Kingma, C. M.; Wit, H. P.

    2010-01-01

    To investigate the effect on the functioning of the vestibular system of a rupture of Reissner's membrane, artificial endolymph was injected in scala media of ten guinea pigs and vestibular evoked potentials (VsEPs), evoked by vertical acceleration pulses, were measured. Directly after injection of

  6. Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises

    Directory of Open Access Journals (Sweden)

    Esther Bernal Valls

    2006-12-01

    Full Text Available El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.The use of exercises in the treatment of patients with vestibular deficits is increasing in a representative way, what evidences this is a profitable process for this kind of patients. The good results suggest that vestibular exercises permit a postural stability and a decrease in the perception of disequilibrium.

  7. Three-dimensional, virtual reality vestibular rehabilitation for chronic imbalance problem caused by Ménière's disease: a pilot study.

    Science.gov (United States)

    Hsu, Su-Yi; Fang, Te-Yung; Yeh, Shih-Ching; Su, Mu-Chun; Wang, Pa-Chun; Wang, Victoria Y

    2017-08-01

    The purpose of this study was to evaluate a three-dimensional, virtual reality system for vestibular rehabilitation in patients with intractable Ménière's disease and chronic vestibular dysfunction. We included 70 patients (36 for study, 34 as control) with a chronic imbalance problem caused by uncompensated Ménière's disease. The virtual reality vestibular rehabilitation comprised four training tasks (modified Cawthorne-Cooksey exercises: eye, head, extension, and coordination exercises) performed in six training sessions (in 4 weeks). Measurements of the task scores and balance parameters obtained at the baseline and after final training sessions were compared. A significant improvement was observed in extension and coordination scores. Patients in the early stages of Ménière's disease had a significantly greater improvement in the center of gravity sway and trajectory excursion in the mediolateral direction than did patients in the late stages of Ménière's disease. Mild functional disability attributable to Ménière's disease was a predictor of improvement in the statokinesigram and maximum trajectory excursion in the anteroposterior direction after rehabilitation. The control group showed no significant improvement in almost all parameters. Virtual reality vestibular rehabilitation may be useful in patients with Ménière's disease, particular those in the early stages or having mild functional disability. Implication for rehabilitation Chronic imbalance caused by uncompensated Ménière's disease is an indication for vestibular rehabilitation. The interactive virtual reality video game, when integrated into vestibular rehabilitation exercise protocol, may assist patients who have mild disability Ménière's disease and who cannot benefit from treatment with drugs or surgery. The initial data from this study support the applicability of three-dimensional virtual reality technology in vestibular rehabilitation programs. The technology gives

  8. Characterization of Cochlear, Vestibular and Cochlear-Vestibular Electrically Evoked Compound Action Potentials in Patients with a Vestibulo-Cochlear Implant

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    T. A. K. Nguyen

    2017-11-01

    Full Text Available The peripheral vestibular system is critical for the execution of activities of daily life as it provides movement and orientation information to motor and sensory systems. Patients with bilateral vestibular hypofunction experience a significant decrease in quality of life and have currently no viable treatment option. Vestibular implants could eventually restore vestibular function. Most vestibular implant prototypes to date are modified cochlear implants to fast-track development. These use various objective measurements, such as the electrically evoked compound action potential (eCAP, to supplement behavioral information. We investigated whether eCAPs could be recorded in patients with a vestibulo-cochlear implant. Specifically, eCAPs were successfully recorded for cochlear and vestibular setups, as well as for mixed cochlear-vestibular setups. Similarities and slight differences were found for the recordings of the three setups. These findings demonstrated the feasibility of eCAP recording with a vestibulo-cochlear implant. They could be used in the short term to reduce current spread and avoid activation of non-targeted neurons. More research is warranted to better understand the neural origin of vestibular eCAPs and to utilize them for clinical applications.

  9. Vestibular and motor contributions to mobility: limitations of seniors awaiting discharge from hospital care.

    Science.gov (United States)

    Golder, Michelle D; Earl, E Marie; Mallery, Laurie H

    2012-12-01

    Following hospitalization, seniors are at risk of impaired mobility and increased risk of falling, which can lead to injuries and re-admission. The primary purpose of this paper was to evaluate the ability of hospitalized seniors to use vestibular inputs for balance control. The secondary purpose was to examine the influence of vestibular function and lower limb muscle strength on mobility. Experimental and correlation designs were used. Patients (aged 65-90 years), preparing for discharge from an inpatient geriatric rehabilitation unit, were recruited. Vestibular control of standing balance was measured using the Clinical Test of Sensory Interaction for Balance (CTSIB). Mobility was measured with the Timed Up and Go (TUG) Test. Lower limb muscle maximum voluntary isometric contraction (MVIC) strength was tested with portable dynamometry. Wilcoxon signed rank test, with alpha adjusted for multiple comparisons (p ≤ 0.017), was used to compare relevant components of the CTSIB. Stepwise regression was used to assess the influence of vestibular impairment on TUG score. CTSIB(Test6) (median = 7.1 seconds, range = 0.0-30.0) was less than CTSIB(Test1) (30.0 seconds, 30.0-30.0) and CTSIB(Test4) (30.0 seconds, 10.5-30.0) (W = 136, p < 0.017). MVIC scores (Nm·kg⁻¹, mean ± SD) included hip abduction 0.38 ± 0.2, hip flexion 0.32 ± 0.1, hip extension 0.44 ± 0.2, knee flexion 0.31 ± 0.1, knee extension 0.33 ± 0.2, ankle dorsiflexion 0.12 ± 0.1 and ankle plantarflexion 0.23 ± 0.1. Mean TUG score was 26.1 ± 6.0 seconds. Performance on CTSIB(Test6) explained 55% of the variance in TUG scores, whereas hip extension strength explained an additional 6%. Seniors awaiting discharge from hospital had impaired vestibular control of balance that was systematically associated with impaired mobility. Evaluating vestibular function prior to discharge from hospital could improve discharge planning with respect to

  10. Enhancement of Otolith Specific Ocular Responses Using Vestibular Stochastic Resonance

    Science.gov (United States)

    Fiedler, Matthew; De Dios, Yiri E.; Esteves, Julie; Galvan, Raquel; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar

    2011-01-01

    Introduction: Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Our goal is to develop a countermeasure based on vestibular stochastic resonance (SR) that could improve central interpretation of vestibular input and mitigate these risks. SR is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. Methods: Eye movement data were collected from 10 subjects during variable radius centrifugation (VRC). Subjects performed 11 trials of VRC that provided equivalent tilt stimuli from otolith and other graviceptor input without the normal concordant canal cues. Bipolar stochastic electrical stimulation, in the range of 0-1500 microamperes, was applied to the vestibular system using a constant current stimulator through electrodes placed over the mastoid process behind the ears. In the VRC paradigm, subjects were accelerated to 216 deg./s. After the subjects no longer sensed rotation, the chair oscillated along a track at 0.1 Hz to provide tilt stimuli of 10 deg. Eye movements were recorded for 6 cycles while subjects fixated on a target in darkness. Ocular counter roll (OCR) movement was calculated from the eye movement data during periods of chair oscillations. Results: Preliminary analysis of the data revealed that 9 of 10 subjects showed an average increase of 28% in the magnitude of OCR responses to the equivalent tilt stimuli while experiencing vestibular SR. The signal amplitude at which performance was maximized was in the range of 100-900 microamperes. Discussion: These results indicate that stochastic electrical stimulation of the vestibular system can improve otolith specific responses. This will have a

  11. Genetics of peripheral vestibular dysfunction: lessons from mutant mouse strains.

    Science.gov (United States)

    Jones, Sherri M; Jones, Timothy A

    2014-03-01

    A considerable amount of research has been published about genetic hearing impairment. Fifty to sixty percent of hearing loss is thought to have a genetic cause. Genes may also play a significant role in acquired hearing loss due to aging, noise exposure, or ototoxic medications. Between 1995 and 2012, over 100 causative genes have been identified for syndromic and nonsyndromic forms of hereditary hearing loss. Mouse models have been extremely valuable in facilitating the discovery of hearing loss genes and in understanding inner ear pathology due to genetic mutations or elucidating fundamental mechanisms of inner ear development. Whereas much is being learned about hereditary hearing loss and the genetics of cochlear disorders, relatively little is known about the role genes may play in peripheral vestibular impairment. Here we review the literature with regard to genetics of vestibular dysfunction and discuss what we have learned from studies using mutant mouse models and direct measures of peripheral vestibular neural function. Several genes are considered that when mutated lead to varying degrees of inner ear vestibular dysfunction due to deficits in otoconia, stereocilia, hair cells, or neurons. Behavior often does not reveal the inner ear deficit. Many of the examples presented are also known to cause human disorders. Knowledge regarding the roles of particular genes in the operation of the vestibular sensory apparatus is growing, and it is clear that gene products co-expressed in the cochlea and vestibule may play different roles in the respective end organs. The discovery of new genes mediating critical inner ear vestibular function carries the promise of new strategies in diagnosing, treating, and managing patients as well as predicting the course and level of morbidity in human vestibular disease. American Academy of Audiology.

  12. The effects of aging on clinical vestibular evaluations

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    Maxime eMaheu

    2015-09-01

    Full Text Available Balance disorders are common issues for aging populations due to the effects of normal aging on peripheral vestibular structures. These changes affect the results of vestibular function evaluations and make the interpretation of these results more difficult. The objective of this article is to review the current state of knowledge of clinically relevant vestibular measures. We will first focus on otolith function assessment methods cVEMP and oVEMP, then the caloric and vHIT methods for semi-circular canals assessment. cVEMP and oVEMP are useful methods, though research on the effects of age for some parameters are still inconclusive. vHIT results are largely independent of age as compared to caloric stimulation and should therefore be preferred for the evaluation of the semi-circular canals function.

  13. Molecular studies of vestibular schwannomas: a review.

    Science.gov (United States)

    Welling, D Bradley; Packer, Mark D; Chang, Long-Sheng

    2007-10-01

    To summarize advances in understanding the molecular biology of vestibular schwannomas over the past year. The role of the neurofibromatosis type 2 protein, denoted as merlin or schwannomin, in embryonic development, cellular adherence, and in cell proliferation has become better elucidated in the past year. Likewise, the role of merlin in Schwann cell-axon interaction has been studied. Additionally, two comprehensive analyses of the spectrum of human neurofibromatosis type 2 mutations have been compiled which make up a valuable resource in understanding critical regions of the neurofibromatosis type 2 gene. Neurofibromatosis type 2 screening guidelines for young patients with solitary vestibular schwannomas have been published. The role of electromagnetic radiation via cellular and portable telephones as a predisposing factor to vestibular schwannoma formation has also been the topic of several studies. Based on increased knowledge of the pathways in which merlin functions and the available transgenic and xenograft mouse models, preliminary data regarding directed pharmacotherapy are also summarized. With increased knowledge of the pathologic mechanisms and interacting proteins associated with merlin, the research community is poised to begin trials of targeted interventions in vitro and in the current mouse models.

  14. Task, muscle and frequency dependent vestibular control of posture

    NARCIS (Netherlands)

    Forbes, P.A.; Siegmund, G.P.; Schouten, A.C.; Blouin, J.S.

    2015-01-01

    The vestibular system is crucial for postural control; however there are considerable differences in the task dependence and frequency response of vestibular reflexes in appendicular and axial muscles. For example, vestibular reflexes are only evoked in appendicular muscles when vestibular

  15. Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders.

    Science.gov (United States)

    Manso, Andréa; Ganança, Mauricio Malavasi; Caovilla, Heloisa Helena

    2016-01-01

    Visual stimuli can induce vestibular adaptation and recovery of body balance. To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD) (experimental group) or Cawthorne-Cooksey exercises (control group). The Dizziness Handicap Inventory (DHI), dizziness analog scale, and the sensitized Romberg static balance and one-leg stance tests were applied before and after the intervention. Before and after the intervention, there was no difference between the experimental and control groups (p>0.005) regarding the findings of DHI, dizziness analog scale, and static balance tests. After the intervention, the experimental and control groups showed lower values (p<0.05) in the DHI and the dizziness analog scale, and higher values (p<0.05) in the static balance tests in some of the assessed conditions. The inclusion of visual stimuli by digital images on vestibular and body balance rehabilitation is effective in reducing dizziness and improving quality of life and postural control in individuals with peripheral vestibular disorders. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  16. Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders

    Directory of Open Access Journals (Sweden)

    Andréa Manso

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Visual stimuli can induce vestibular adaptation and recovery of body balance. OBJECTIVE: To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. METHODS: Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD (experimental group or Cawthorne-Cooksey exercises (control group. The Dizziness Handicap Inventory (DHI, dizziness analog scale, and the sensitized Romberg static balance and one-leg stance tests were applied before and after the intervention. RESULTS: Before and after the intervention, there was no difference between the experimental and control groups (p > 0.005 regarding the findings of DHI, dizziness analog scale, and static balance tests. After the intervention, the experimental and control groups showed lower values (p < 0.05 in the DHI and the dizziness analog scale, and higher values (p < 0.05 in the static balance tests in some of the assessed conditions. CONCLUSION: The inclusion of visual stimuli by digital images on vestibular and body balance rehabilitation is effective in reducing dizziness and improving quality of life and postural control in individuals with peripheral vestibular disorders.

  17. Acoustic neuroma: predominance of Antoni type B cells in tumors of patients with vestibular paresis.

    Science.gov (United States)

    Stipkovits, E M; Graamans, K; Jansen, G H; Velthof, M A

    2001-03-01

    This study aimed to investigate whether in patients with acoustic neuroma (AN), the presence or absence of vestibular symptoms is related to the histologic characteristics of the tumor. The study design was a retrospective clinical study. The study was conducted at a tertiary referral center. A group of eight patients with unilateral AN and normal vestibular function was compared with a group of AN patients, matched for tumor size, with vestibular paresis. The methods were vestibular examination of the patients and morphometric analysis of the histologic specimens of their tumors. The outcomes were measured by vestibular function and by the relative quantity of Antoni type A or type B cell tissue. The tumors of patients with vestibular paresis appeared to contain significantly more Antoni B cells and fewer Antoni A cells than did the tumors of patients with normal vestibular function. Besides morphologic differences, type B cells may display a distinct behavior compared with type A cells. Presumably, in AN patients the development of a vestibular paresis appears to be related to the biologic activity of type B cells in the tumor.

  18. Vestibular schwannoma: an unusual post radiotherapy response.

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    Uddin, Najam; Iqbal, Muhammad; Memon, Muhammad Ali; Farrukh, Salman

    2014-11-01

    Vestibular schwannoma is a relatively uncommon tumor. Although, it is benign but locally expansile and spreads to damage the adjacent structures. Treatment strategy includes surgery, Stereotactic Radiosurgery (SRS) either by standard or hypofractionated protocols. Due to its benign nature, radiation therapy cannot remove the tumor completely, instead radiation therapy halts the growth of vestibular schwannoma and inactivates this benign tumor. Response of radiation in the form of tumor shrinkage is seen 2 - 2.5 years after the radiations. We report a case of vestibular Schwannoma in which residual tumor of 3.1 cm size following subtotal resection was irradiated of the dose of 54 Gy in 30 equal fractions on 3-Dimensional Conformal Radiation Therapy (3-DCRT). A follow-up CT scan brain after 2 months of radiotherapy showed complete disappearance of the disease categorized as complete response. This is an unusual phenomenon and is likely due to the very rarely seen malignant transformation or presence of malignant component in this benign tumor.

  19. Laboratory testing of the vestibular system.

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    Clarke, Andrew H

    2010-10-01

    Recent reports on vestibular testing, relevant to clinical diagnosis, are reviewed.Besides the case history and bedside examination, objective measurement of the vestibuloocular reflex in all of its facets remains the cornerstone in the diagnostic process. In recent years, this has been enhanced considerably by reliable unilateral tests for the otolith organs, most notably by vestibular-evoked myogenic potential recording and estimation of subjective visual vertical. In addition, progress has been made in the investigation of multisensory interaction, involving visual acuity and posturography.Technological developments include improved eye movement measurement techniques, electrotactile and vibrotactile sensory enhancement or substitution, the use of virtual reality devices and motion stimulators such as hexapods and the rediscovery of galvanic vestibular stimulation as a research and diagnostic tool. The recent introduction of new tests, together with the development of novel technologies, is gradually increasing the scope of the physical and bedside examination of the dizzy patient (see chapter 'Medical management of peripheral disorders' in this issue). The use of more complex equipment, such as rotating chairs, linear sleds, hexapods and posturography platforms, is likely to become limited to specialized laboratories and rehabilitation centers in future years. Further, high resolution magnetic resonance tomography (MRT) and computed tomography have allowed insight into the morphology and determination of malformations of the human labyrinth.

  20. Age-Related Vestibular Loss: Current Understanding and Future Research Directions.

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    Arshad, Qadeer; Seemungal, Barry M

    2016-01-01

    The vestibular system sub-serves a number of reflex and perceptual functions, comprising the peripheral apparatus, the vestibular nerve, the brainstem and cerebellar processing circuits, the thalamic relays, and the vestibular cerebral cortical network. This system provides signals of self-motion, important for gaze and postural control, and signals of traveled distance, for spatial orientation, especially in the dark. Current evidence suggests that certain aspects of this multi-faceted system may deteriorate with age and sometimes with severe consequences, such as falls. Often the deterioration in vestibular functioning relates to how the signal is processed by brain circuits rather than an impairment in the sensory transduction process. We review current data concerning age-related changes in the vestibular system, and how this may be important for clinicians dealing with balance disorders.

  1. Age-Related Vestibular Loss: Current Understanding and Future Research Directions

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    Dominic Allen

    2016-12-01

    Full Text Available The vestibular system sub-serves a number of reflex and perceptual functions, comprising the peripheral apparatus, the vestibular nerve, the brainstem and cerebellar processing circuits, the thalamic relays, and the vestibular cerebral cortical network. This system provides signals of self-motion, important for gaze and postural control, and signals of traveled distance, for spatial orientation, especially in the dark. Current evidence suggests that certain aspects of this multi-faceted system may deteriorate with age and sometimes with severe consequences, such as falls. Often the deterioration in vestibular functioning relates to how the signal is processed by brain circuits rather than an impairment in the sensory transduction process. We review current data concerning age-related changes in the vestibular system, and how this may be important for clinicians dealing with balance disorders.

  2. The role of the thalamus in the human subcortical vestibular system.

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    Conrad, Julian; Baier, Bernhard; Dieterich, Marianne

    2014-01-01

    Most of our knowledge concerning central vestibular pathways is derived from animal studies while evidence of the functional importance and localization of these pathways in humans is less well defined. The termination of these pathways at the thalamic level in humans is even less known. In this review we summarize the findings concerning the central subcortical vestibular pathways in humans and the role of these structures in the central vestibular system with regard to anatomical localization and function. Also, we review the role of the thalamus in the pathogenesis of higher order sensory deficits such as spatial neglect, pusher syndrome or thalamic astasia and the correlation of these phenomena with findings of a vestibular tone imbalance at the thalamic level. By highlighting thalamic structures involved in vestibular signal processing and relating the different nomenclatures we hope to provide a base for future studies on thalamic sensory signal processing.

  3. Vestibular findings in fibromyalgia patients

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    Zeigelboim, Bianca Simone

    2011-07-01

    Full Text Available Introduction: Fibromyalgia (FM is a non-inflammatory musculoskeletal chronic syndrome, whose etiology is unknown, characterized by a diffuse pain, increase in palpation sensitivity and such symptoms as tiredness, insomnia, anxiety, depression, cold intolerance and otologic complaints. Objective: Evaluate the vestibular behavior in fibromyalgia patients. Method: A retrospective transversal study was performed. 25 patients aged between 26 and 65 (average age - 52.2 and standard deviation - 10.3 were evaluated and submitted to the following procedures: anamnesis, otorhinolaryngologic and vestibular evaluation by way of vector electronystamography. Results: a The most evident otoneurologic symptoms were: difficulty or pain when moving the neck and pain was spread to an arm or shoulder (92.0% in each, dizziness (84.0% and headache (76.0%. The different clinical symptoms mostly reported were: depression (80.0%, anxiety (76.0% and insomnia (72.0%; b vestibular examination showed an alteration in 12 patients (48.0% in the caloric test; c an alteration in the peripheral vestibular system prevailed, and d deficient peripheral vestibular disorders were prevalent. Conclusion: This study enabled the importance of the labyrinthic test to be verified, thus emphasizing that this kind of people must be studied better, since a range of rheumatologic diseases can cause severe vestibular changes as a result of their manifestations and impairment areas.

  4. Vestibular rehabilitation ameliorates chronic dizziness through the SIRT1 axis

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    Chung-Lan eKao

    2014-03-01

    Full Text Available Dizziness is a common clinical symptom frequently referred to general neurologists and practitioners. Exercise intervention, in the form of vestibular rehabilitation, is known as an effective clinical management for dizziness. This intervention is reported to have a functional role in correcting dizziness, improving gaze stability, retraining balance and gait and enhancing physical fitness. Dizziness is known to be highly related to inflammation and oxidative stress. SIRT1 is a major molecule for regulation of inflammation and mitigation of oxidative stress in chronic diseases such as atherosclerosis and chronic obstructive pulmonary disease. However, the bio-molecular roles of SIRT1 involved in the pathogenesis of dizziness are still largely unclear. In this study, a total of 30 subjects were recruited (15 patients with chronic dizziness, and 15 age/gender matched non-dizzy control subjects. The dizzy subjects group received 18 sessions of 30-minutes vestibular training. We found that the mRNA and protein expression levels of SIRT1 in the blood samples of chronic dizzy patients were repressed compared with those of healthy controls. After vestibular training, the dizzy patients had significant symptomatic improvements. The SIRT1 expression and its downstream genes (PPAR-γ and PGC-1α were upregulated after vestibular exercises in dizzy subjects. Notably, the catalytic activity of SIRT1, NADPH and antioxidant enzyme activities were also activated in dizzy patients after vestibular training. Furthermore, vestibular exercise training reduced oxidative events and p53 expression in patients with dizziness. This study demonstrated that vestibular exercise training improved dizziness symptoms, and mechanisms for alleviation of chronic dizziness may partly involve the activation of the SIRT1 axis and the repression of redox status.

  5. Complex vestibular macular anatomical relationships need a synthetic approach

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    Ross, M. D.

    2001-01-01

    Mammalian vestibular maculae are anatomically organized for complex parallel processing of linear acceleration information. Anatomical findings in rat maculae are provided in order to underscore this complexity, which is little understood functionally. This report emphasizes that a synthetic approach is critical to understanding how maculae function and the kind of information they conduct to the brain.

  6. Electrophysiological Measurements of Peripheral Vestibular Function—A Review of Electrovestibulography

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    Brown, Daniel J.; Pastras, Christopher J.; Curthoys, Ian S.

    2017-01-01

    Electrocochleography (EcochG), incorporating the Cochlear Microphonic (CM), the Summating Potential (SP), and the cochlear Compound Action Potential (CAP), has been used to study cochlear function in humans and experimental animals since the 1930s, providing a simple objective tool to assess both hair cell (HC) and nerve sensitivity. The vestibular equivalent of ECochG, termed here Electrovestibulography (EVestG), incorporates responses of the vestibular HCs and nerve. Few research groups have utilized EVestG to study vestibular function. Arguably, this is because stimulating the cochlea in isolation with sound is a trivial matter, whereas stimulating the vestibular system in isolation requires significantly more technical effort. That is, the vestibular system is sensitive to both high-level sound and bone-conducted vibrations, but so is the cochlea, and gross electrical responses of the inner ear to such stimuli can be difficult to interpret. Fortunately, several simple techniques can be employed to isolate vestibular electrical responses. Here, we review the literature underpinning gross vestibular nerve and HC responses, and we discuss the nomenclature used in this field. We also discuss techniques for recording EVestG in experimental animals and humans and highlight how EVestG is furthering our understanding of the vestibular system. PMID:28620284

  7. Electrophysiological Measurements of Peripheral Vestibular Function—A Review of Electrovestibulography

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    Daniel J. Brown

    2017-05-01

    Full Text Available Electrocochleography (EcochG, incorporating the Cochlear Microphonic (CM, the Summating Potential (SP, and the cochlear Compound Action Potential (CAP, has been used to study cochlear function in humans and experimental animals since the 1930s, providing a simple objective tool to assess both hair cell (HC and nerve sensitivity. The vestibular equivalent of ECochG, termed here Electrovestibulography (EVestG, incorporates responses of the vestibular HCs and nerve. Few research groups have utilized EVestG to study vestibular function. Arguably, this is because stimulating the cochlea in isolation with sound is a trivial matter, whereas stimulating the vestibular system in isolation requires significantly more technical effort. That is, the vestibular system is sensitive to both high-level sound and bone-conducted vibrations, but so is the cochlea, and gross electrical responses of the inner ear to such stimuli can be difficult to interpret. Fortunately, several simple techniques can be employed to isolate vestibular electrical responses. Here, we review the literature underpinning gross vestibular nerve and HC responses, and we discuss the nomenclature used in this field. We also discuss techniques for recording EVestG in experimental animals and humans and highlight how EVestG is furthering our understanding of the vestibular system.

  8. Vestibular Loss Predicts Poorer Spatial Cognition in Patients with Alzheimer's Disease.

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    Wei, Eric X; Oh, Esther S; Harun, Aisha; Ehrenburg, Matthew; Agrawal, Yuri

    2018-01-01

    The vestibular system is an important contributor to balance control, spatial orientation, and falls risk. Recent evidence has shown that Alzheimer's disease (AD) patients have a higher prevalence of vestibular impairment relative to healthy controls. We sought to evaluate whether vestibular loss is specifically associated with poor spatial cognitive skills among patients with mild cognitive impairment (MCI) and AD. We enrolled 50 patients (22 MCI and 28 AD) from an interdisciplinary Memory Clinic and measured vestibular physiologic function in all patients. Spatial cognitive function was assessed using the Money Road Map Test (MRMT) and the Trail Making Test Part B (TMT-B). General cognitive function was assessed with the Mini-Mental Status Examination (MMSE). In multivariable linear regression analyses adjusted for age, gender, education level, and MMSE, MCI and AD patients with vestibular loss made significantly more errors on the MRMT relative to patients with normal vestibular function (β= 7.3, 95% CI 2.4, 12.1 for unilateral vestibular loss and β= 6.4, 95% CI 1.9, 10.9 for bilateral vestibular loss). We further stratified AD patients into "spatially normal" and "spatially impaired" groups based on MRMT performance, and found that the prevalence of vestibular loss was significantly higher in the spatially impaired AD group relative to the spatially normal AD group. These findings support the hypothesis that vestibular loss contributes specifically to a decline in spatial cognitive ability in MCI and AD patients, independently of general cognitive decline, and may predict a "spatially impaired" subtype of AD.

  9. Vestibular information is necessary for maintaining metric properties of representational space: evidence from mental imagery.

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    Péruch, Patrick; Lopez, Christophe; Redon-Zouiteni, Christine; Escoffier, Guy; Zeitoun, Alain; Sanjuan, Mélanie; Devèze, Arnaud; Magnan, Jacques; Borel, Liliane

    2011-09-01

    The vestibular system contributes to a wide range of functions, from postural and oculomotor reflexes to spatial representation and cognition. Vestibular signals are important to maintain an internal, updated representation of the body position and movement in space. However, it is not clear to what extent they are also necessary to mentally simulate movement in situations that do not involve displacements of the body, as in mental imagery. The present study assessed how vestibular loss can affect object-based mental transformations (OMTs), i.e., imagined rotations or translations of objects relative to the environment. Participants performed one task of mental rotation of 3D-objects and two mental scanning tasks dealing with the ability to build and manipulate mental images that have metric properties. Menière's disease patients were tested before unilateral vestibular neurotomy and during the recovery period (1 week and 1 month). They were compared to healthy participants tested at similar time intervals and to bilateral vestibular-defective patients tested after the recovery period. Vestibular loss impaired all mental imagery tasks. Performance varied according to the extent of vestibular loss (bilateral patients were frequently the most impaired) and according to the time elapsed after unilateral vestibular neurotomy (deficits were stronger at the early stage after neurotomy and then gradually compensated). These findings indicate that vestibular signals are necessary to perform OMTs and provide the first demonstration of the critical role of vestibular signals in processing metric properties of mental representations. They suggest that vestibular loss disorganizes brain structures commonly involved in mental imagery, and more generally in mental representation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. The differential effects of acute right- vs. left-sided vestibular failure on brain metabolism.

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    Becker-Bense, Sandra; Dieterich, Marianne; Buchholz, Hans-Georg; Bartenstein, Peter; Schreckenberger, Mathias; Brandt, Thomas

    2014-07-01

    The human vestibular system is represented in the brain bilaterally, but it has functional asymmetries, i.e., a dominance of ipsilateral pathways and of the right hemisphere in right-handers. To determine if acute right- or left-sided unilateral vestibular neuritis (VN) is associated with differential patterns of brain metabolism in areas representing the vestibular network and the visual-vestibular interaction, patients with acute VN (right n = 9; left n = 13) underwent resting state (18)F-FDG PET once in the acute phase and once 3 months later after central vestibular compensation. The contrast acute vs. chronic phase showed signal differences in contralateral vestibular areas and the inverse contrast in visual cortex areas, both more pronounced in VN right. In VN left additional regions were found in the cerebellar hemispheres and vermis bilaterally, accentuated in severe cases. In general, signal changes appeared more pronounced in patients with more severe vestibular deficits. Acute phase PET data of patients compared to that of age-matched healthy controls disclosed similarities to these patterns, thus permitting the interpretation that the signal changes in vestibular temporo-parietal areas reflect signal increases, and in visual areas, signal decreases. These data imply that brain activity in the acute phase of right- and left-sided VN exhibits different compensatory patterns, i.e., the dominant ascending input is shifted from the ipsilateral to the contralateral pathways, presumably due to the missing ipsilateral vestibular input. The visual-vestibular interaction patterns were preserved, but were of different prominence in each hemisphere and more pronounced in patients with right-sided failure and more severe vestibular deficits.

  11. Cervical vestibular evoked myogenic potentials in children with spastic cerebral palsy and normal children with 7-12 years of age

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    Nazila Akbarfahimi

    2014-10-01

    Full Text Available Background and Aim: Cervical vestibular-evoked myogenic potential (cVEMP is one of the diagnostic tests used in assessing vestibular function. Two aims of this study were to investigate implications of cervical vestibular evoked myogenic potential in children with spastic cerebral palsy (7-12 years, and to compare vestibular function in these children and normal children.Methods: In this cross-sectional study, myogenic potential was recorded in 31 children with spastic cerebral palsy (8 girls, 23 boys,7-12 years of age, with mean age of 8.77 years old and standard deviation of 1.52 years and 31 normal children (13 girls, 18 boys with mean age of 8.77 years and standard deviation of 1.52 years. Cervical vestibular evoked myogenic potential was recorded with 500 Hz tone burst. The recorded parameters included p13 and n23 latency, p13-n23 pick to pick amplitude, and threshold.Results: Myogenic Potential was recorded in 31 normal children. They had bilateral responses. In children with cerebral palsy, 21 children showed bilateral responses, 3 children had only right-sided responses, 8 children had only left-sided responses, and two children did not show any responses. The statistical significant differences were shown between the two groups in n23, p13-n23 pick to pick amplitude, and threshold (p<0.05.Conclusion: These findings showed that cervical vestibular evoked myogenic potential can be used in children with cerebral palsy. There were significant differences in myogenic potential parameters between the two groups. More studies are needed to investigate the causes of these differences.

  12. Plasticity during vestibular compensation: the role of saccades

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    Hamish Gavin MacDougall

    2012-02-01

    Full Text Available This paper is focussed on one major aspect of compensation: the recent behavioural findings concerning oculomotor responses in human vestibular compensation and their possible implications for recovery after unilateral vestibular loss (UVL. New measurement techniques have provided new insights into how patients recover after UVL and have given clues for vestibular rehabilitation. Prior to this it has not been possible to quantify the level of function of all the peripheral vestibular sense organs. Now it is. By using vestibular-evoked myogenic potentials to measure utricular and saccular function and by new video head impulse testing to measure semicircular canal function to natural values of head accelerations. With these new video procedures it is now possible to measure both slow phase eye velocity and also saccades during natural head movements. The present evidence is that there is little or no recovery of slow phase eye velocity responses to natural head accelerations. It is doubtful as to whether the modest changes in slow phase eye velocity to small angular accelerations are functionally effective during compensation. On the other hand it is now clear that saccades can play a very important role in helping patients compensate and return to a normal lifestyle. Preliminary evidence suggests that different patterns of saccadic response may predict how well patients recover. It may be possible to train patients to produce more effective saccadic patterns in the first days after their unilateral loss. Some patients do learn new strategies, new behaviours, to conceal their inadequate VOR but when those strategies are prevented from operating by using passive, unpredictable, high acceleration natural head movements, as in the head impulse test, their vestibular loss can be demonstrated. It is those very strategies which the tests exclude, which may be the cause of their successful compensation.

  13. The effect of vestibular rehabilitation on adults with bilateral vestibular hypofunction: a systematic review.

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    Porciuncula, Franchino; Johnson, Connie C; Glickman, Leslie B

    2012-01-01

    Adults with bilateral vestibular hypofunction (BVH) experience significant disability. A systematic review assessed evidence for vestibular rehabilitation (VR). NUMBER OF STUDIES: 14 studies. Search identification of studies based on inclusion criteria: (a) population: adults with BVH of peripheral origin; (b) interventions: vestibular exercises, balance training, education, or sensory prosthetics; (c) comparison: single interventions or compared to another psychophysical intervention, placebo, or healthy population; (d) outcomes: based on International Classification of Functioning, Disability and Health (ICF) Body Functions and Structure, Activity, and Participation; (e) study designs: prospective and interventional, Levels of Evidence I to III per Centre of Evidence-based Medicine grading. Coding and appraisal based on ICF framework and strength of evidence synthesis. Five Level II studies and nine Level III studies: All had outcomes on gaze and postural stability, five with outcomes on gait speed and perceptions of oscillopsia and disequilibrium. (a) Moderate evidence strength on improved gaze and postural stability (ICF-Body Functions) following exercise-based VR; (b) Inadequate number of studies supporting benefit of VR on ICF-Participation outcomes; (c) Sensory prosthetics in early phase of development. Moderate evidence strength in support of VR from an impairment level; clinical practice and research needed to explore interventions extending to ICF-Activity and Participation.

  14. Impaired math achievement in patients with acute vestibular neuritis.

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    Moser, Ivan; Vibert, Dominique; Caversaccio, Marco D; Mast, Fred W

    2017-12-01

    Broad cognitive difficulties have been reported in patients with peripheral vestibular deficit, especially in the domain of spatial cognition. Processing and manipulating numbers relies on the ability to use the inherent spatial features of numbers. It is thus conceivable that patients with acute peripheral vestibular deficit show impaired numerical cognition. Using the number Stroop task and a short math achievement test, we tested 20 patients with acute vestibular neuritis and 20 healthy, age-matched controls. On the one hand, patients showed normal congruency and distance effects in the number Stroop task, which is indicative of normal number magnitude processing. On the other hand, patients scored lower than healthy controls in the math achievement test. We provide evidence that the lower performance cannot be explained by either differences in prior math knowledge (i.e., education) or slower processing speed. Our results suggest that peripheral vestibular deficit negatively affects numerical cognition in terms of the efficient manipulation of numbers. We discuss the role of executive functions in math performance and argue that previously reported executive deficits in patients with peripheral vestibular deficit provide a plausible explanation for the lower math achievement scores. In light of the handicapping effects of impaired numerical cognition in daily living, it is crucial to further investigate the mechanisms that cause mathematical deficits in acute PVD and eventually develop adequate means for cognitive interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Vestibular-related frontal cortical areas and their roles in smooth-pursuit eye movements: representation of neck velocity, neck-vestibular interactions and memory-based smooth-pursuit

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    Kikuro eFukushima

    2011-12-01

    Full Text Available Smooth-pursuit eye movements are voluntary responses to small slow-moving objects in the fronto-parallel plane. They evolved in primates, who possess high-acuity foveae, to ensure clear vision about the moving target. The primate frontal cortex contains two smooth-pursuit related areas; the caudal part of the frontal eye fields (FEF and the supplementary eye fields (SEF. Both areas receive vestibular inputs. We review functional differences between the two areas in smooth-pursuit. Most FEF pursuit neurons signal pursuit parameters such as eye velocity and gaze-velocity, and are involved in cancelling the vestibulo-ocular reflex by linear addition of vestibular and smooth-pursuit responses. In contrast, gaze-velocity signals are rarely represented in the SEF. Most FEF pursuit neurons receive neck velocity inputs, while discharge modulation during pursuit and trunk-on-head rotation adds linearly. Linear addition also occurs between neck velocity responses and vestibular responses during head-on-trunk rotation in a task-dependent manner. During cross-axis pursuit-vestibular interactions, vestibular signals effectively initiate predictive pursuit eye movements. Most FEF pursuit neurons discharge during the interaction training after the onset of pursuit eye velocity, making their involvement unlikely in the initial stages of generating predictive pursuit. Comparison of representative signals in the two areas and the results of chemical inactivation during a memory-based smooth-pursuit task indicate they have different roles; the SEF plans smooth-pursuit including working memory of motion-direction, whereas the caudal FEF generates motor commands for pursuit eye movements. Patients with idiopathic Parkinson’s disease were asked to perform this task, since impaired smooth-pursuit and visual working memory deficit during cognitive tasks have been reported in most patients. Preliminary results suggested specific roles of the basal ganglia in memory

  16. Vestibular-related frontal cortical areas and their roles in smooth-pursuit eye movements: representation of neck velocity, neck-vestibular interactions, and memory-based smooth-pursuit.

    Science.gov (United States)

    Fukushima, Kikuro; Fukushima, Junko; Warabi, Tateo

    2011-01-01

    Smooth-pursuit eye movements are voluntary responses to small slow-moving objects in the fronto-parallel plane. They evolved in primates, who possess high-acuity foveae, to ensure clear vision about the moving target. The primate frontal cortex contains two smooth-pursuit related areas; the caudal part of the frontal eye fields (FEF) and the supplementary eye fields (SEF). Both areas receive vestibular inputs. We review functional differences between the two areas in smooth-pursuit. Most FEF pursuit neurons signal pursuit parameters such as eye velocity and gaze-velocity, and are involved in canceling the vestibulo-ocular reflex by linear addition of vestibular and smooth-pursuit responses. In contrast, gaze-velocity signals are rarely represented in the SEF. Most FEF pursuit neurons receive neck velocity inputs, while discharge modulation during pursuit and trunk-on-head rotation adds linearly. Linear addition also occurs between neck velocity responses and vestibular responses during head-on-trunk rotation in a task-dependent manner. During cross-axis pursuit-vestibular interactions, vestibular signals effectively initiate predictive pursuit eye movements. Most FEF pursuit neurons discharge during the interaction training after the onset of pursuit eye velocity, making their involvement unlikely in the initial stages of generating predictive pursuit. Comparison of representative signals in the two areas and the results of chemical inactivation during a memory-based smooth-pursuit task indicate they have different roles; the SEF plans smooth-pursuit including working memory of motion-direction, whereas the caudal FEF generates motor commands for pursuit eye movements. Patients with idiopathic Parkinson's disease were asked to perform this task, since impaired smooth-pursuit and visual working memory deficit during cognitive tasks have been reported in most patients. Preliminary results suggested specific roles of the basal ganglia in memory-based smooth-pursuit.

  17. Allicin protects against cisplatin-induced vestibular dysfunction by inhibiting the apoptotic pathway.

    Science.gov (United States)

    Wu, Xianmin; Cai, Jing; Li, Xiaofei; Li, He; Li, Jianfeng; Bai, Xiaohui; Liu, Wenwen; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo; Fan, Zhaomin

    2017-06-15

    Cisplatin is an anticancer drug that causes the impairment of inner ear function as side effects, including hearing loss and balance dysfunction. The purpose of this study was to investigate the effects of allicin against cisplatin-induced vestibular dysfunction in mice and to make clear the mechanism underlying the protective effects of allicin on oto-vestibulotoxicity. Mice intraperitoneally injected with cisplatin exhibited vestibular dysfunction in swimming test, which agreed with impairment in vestibule. However, these impairments were significantly prevented by pre-treatment with allicin. Allicin markedly reduced cisplatin-activated expression of cleaved-caspase-3 in hair cells and vascular layer cells of utricule, saccule and ampulla, but also decreased AIF nuclear translocation of hair cells in utricule, saccule and ampulla. These results showed that allicin played an effective role in protecting vestibular dysfunction induced by cisplatin via inhibiting caspase-dependent and caspase-independent apoptotic pathways. Therefore, allicin may be useful in preventing oto-vestibulotoxicity mediated by cisplatin. Copyright © 2017. Published by Elsevier B.V.

  18. Electronystagmographic changes in patients with unilateral vestibular schwannomas in relation to tumor progression and central compensation.

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    Stipkovits, E M; Van Dijk, J E; Graamans, K

    1999-01-01

    Vestibular function was studied in a group of 121 patients with unilateral vestibular schwannomas who were referred to University Hospital Utrecht between 1986 and 1996. Testing included the caloric test, torsion test, saccade test, smooth pursuit test and the registration of spontaneous nystagmus. Each patient's symptoms were taken from a chart review. The size of the tumor was expressed as the maximum extrameatal diameter in the axial plane parallel to the petrous ridge as seen in magnetic resonance imaging or computed tomography. Large tumors were significantly more often accompanied by a more severe paresis on caloric testing, a smaller gain on torsion testing, spontaneous nystagmus, an abnormal saccade test and an abnormal smooth pursuit test. The presence of spontaneous nystagmus was significantly more frequently combined with an abnormal smooth pursuit and saccade test. There was a significant correlation between the slow component's velocity of the spontaneous nystagmus and the size and progression of tumor. However, a specific relation between tumor size and central vestibular compensation could not be demonstrated.

  19. Vestibular Modulation of Sympathetic Nerve Activity to Muscle and Skin in Humans

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    Elie Hammam

    2017-07-01

    Full Text Available We review the existence of vestibulosympathetic reflexes in humans. While several methods to activate the human vestibular apparatus have been used, galvanic vestibular stimulation (GVS is a means of selectively modulating vestibular afferent activity via electrodes over the mastoid processes, causing robust vestibular illusions of side-to-side movement. Sinusoidal GVS (sGVS causes partial entrainment of sympathetic outflow to muscle and skin. Modulation of muscle sympathetic nerve activity (MSNA from vestibular inputs competes with baroreceptor inputs, with stronger temporal coupling to the vestibular stimulus being observed at frequencies remote from the cardiac frequency; “super entrainment” was observed in some individuals. Low-frequency (<0.2 Hz sGVS revealed two peaks of modulation per cycle, with bilateral recordings of MSNA or skin sympathetic nerve activity, providing evidence of lateralization of sympathetic outflow during vestibular stimulation. However, it should be noted that GVS influences the firing of afferents from the entire vestibular apparatus, including the semicircular canals. To identify the specific source of vestibular input responsible for the generation of vestibulosympathetic reflexes, we used low-frequency (<0.2 Hz sinusoidal linear acceleration of seated or supine subjects to, respectively, target the utricular or saccular components of the otoliths. While others had discounted the semicircular canals, we showed that the contributions of the utricle and saccule to the vestibular modulation of MSNA are very similar. Moreover, that modulation of MSNA occurs at accelerations well below levels at which subjects are able to perceive any motion indicates that, like vestibulospinal control of posture, the vestibular system contributes to the control of blood pressure through potent reflexes in humans.

  20. Vestibular Modulation of Sympathetic Nerve Activity to Muscle and Skin in Humans

    Science.gov (United States)

    Hammam, Elie; Macefield, Vaughan G.

    2017-01-01

    We review the existence of vestibulosympathetic reflexes in humans. While several methods to activate the human vestibular apparatus have been used, galvanic vestibular stimulation (GVS) is a means of selectively modulating vestibular afferent activity via electrodes over the mastoid processes, causing robust vestibular illusions of side-to-side movement. Sinusoidal GVS (sGVS) causes partial entrainment of sympathetic outflow to muscle and skin. Modulation of muscle sympathetic nerve activity (MSNA) from vestibular inputs competes with baroreceptor inputs, with stronger temporal coupling to the vestibular stimulus being observed at frequencies remote from the cardiac frequency; “super entrainment” was observed in some individuals. Low-frequency (<0.2 Hz) sGVS revealed two peaks of modulation per cycle, with bilateral recordings of MSNA or skin sympathetic nerve activity, providing evidence of lateralization of sympathetic outflow during vestibular stimulation. However, it should be noted that GVS influences the firing of afferents from the entire vestibular apparatus, including the semicircular canals. To identify the specific source of vestibular input responsible for the generation of vestibulosympathetic reflexes, we used low-frequency (<0.2 Hz) sinusoidal linear acceleration of seated or supine subjects to, respectively, target the utricular or saccular components of the otoliths. While others had discounted the semicircular canals, we showed that the contributions of the utricle and saccule to the vestibular modulation of MSNA are very similar. Moreover, that modulation of MSNA occurs at accelerations well below levels at which subjects are able to perceive any motion indicates that, like vestibulospinal control of posture, the vestibular system contributes to the control of blood pressure through potent reflexes in humans. PMID:28798718

  1. [Effect of nitric oxide in vestibular compensation].

    Science.gov (United States)

    Jiang, Zi-dong; Zhang, Lian-shan

    2003-10-01

    To study the effect of nitric oxide (NO) in vestibular compensation after unilateral vestibular deafferentation. Eighteen animals were divided into two groups, 6 of group a as control, 12 of group b received gentamicin intratympanic injection in the left ear. Half of the animals were killed respectively after 5 days and 10 days. Vestibular endorgan and brainstem tissue sections were subjected to NADPH-d reactive test of NOS for histochemical examination. In group a, NOS-like reactivity in both sides of vestibular endorgan and nucli. In group b during 5 days, NOS-like reactivity in right side of vestibular endorgan and nucli, those of the left side were negative. During 10 days, NOS-like reactivity only in the right side of vestibular endorgan. Changes of NOS expression in the contralateral vestibular nucli might have played a role in vestibular compensation.

  2. Treatment of peripheral vestibular dysfunction using photobiomodulation

    Science.gov (United States)

    Lee, Min Young; Hyun, Jai-Hwan; Suh, Myung-Whan; Ahn, Jin-Chul; Chung, Phil-Sang; Jung, Jae Yun; Rhee, Chung Ku

    2017-08-01

    Gentamicin, which is still used in modern medicine, is a known vestibular toxic agent, and various degrees of balance problems have been observed after exposure to this pharmacologic agent. Photobiomodulation is a candidate therapy for vertigo due to its ability to reach deep inner ear organs such as the cochlea. Previous reports have suggested that photobiomodulation can improve hearing and cochlea function. However, few studies have examined the effect of photobiomodulation on balance dysfunction. We used a rat model to mimic human vestibulopathy resulting from gentamicin treatment and evaluated the effect of photobiomodulation on vestibular toxicity. Slow harmonic acceleration (SHA) rotating platform testing was used for functional evaluation and both qualitative and quantitative epifluorescence analyses of cupula histopathology were performed. Animals were divided into gentamicin only and gentamicin plus laser treatment groups. Laser treatment was applied to one ear, and function and histopathology were evaluated in both ears. Decreased function was observed in both ears after gentamicin treatment, demonstrated by low gain and no SHA asymmetry. Laser treatment minimized the damage resulting from gentamicin treatment as shown by SHA asymmetry and recovered gain in the treated ear. Histology results reflected the functional results, showing increased hair cell density and epifluorescence intensity in laser-treated cupulae.

  3. Neuronal nitric oxide synthase immunopositive neurons in cat vestibular complex: a light and electron microscopic study.

    Science.gov (United States)

    Papantchev, V; Paloff, A; Hinova-Palova, D; Hristov, S; Todorova, D; Ovtscharoff, W

    2006-11-01

    Nitric oxide is a unique neurotransmitter, which participates in many physiological and pathological processes in the organism. Nevertheless, there are little data about the neuronal nitric oxide synthase immunoreactivity (nNOS-ir) in the vestibular complex of a cat. In this respect, the aims of this study were to: (1) demonstrate nNOS-ir in the neurons and fibers, from all major and accessory vestibular nuclei; (2) describe their light microscopic morphology and distribution; (3) investigate and analyze the ultrastructure of the NOS I-immunopositive neurons, fibers, and synaptic boutons. For demonstration of the nNOS-ir, the peroxidase-antiperoxidase-diaminobenzidin method was applied. Immunopositive for nNOS neurons and fibers were present in all major and accessory vestibular nuclei. On the light microscope level, the immunopositive neurons were different in shape and size. According to the latter, they were divided into four groups--small (with diameter less than 15 microm), medium-sized (with diameter from 15 to 30 microm), large type I (with diameter from 30 to 40 microm), and large type II (with diameter greater than 40 microm). On the electron microscope level, the immunoproduct was observed in neurons, dendrites, and terminal boutons. According to the ultrastructural features, the neurons were divided into three groups--small (with diameter less than 15 microm), medium-sized (with diameter from 15 to 30 microm), and large (with diameter greater than 30 microm). At least two types of nNOS-ir synaptic boutons were easily distinguished. As a conclusion, we hope that this study will contribute to a better understanding of the functioning of the vestibular complex in cat and that some of the data presented could be extrapolated to other mammals, including human.

  4. RELATIONSHIPS AMONG COMMON VISION AND VESTIBULAR TESTS IN HEALTHY RECREATIONAL ATHLETES

    Science.gov (United States)

    Heick, John D.; Bay, Curt; Dompier, Thomas P.; Valovich McLeod, Tamara C.

    2017-01-01

    Background Disruption of the visual and vestibular systems is commonly observed following concussion. Researchers have explored the utility of screening tools to identify deficits in these systems in concussed patients, but it is unclear if these tests are measuring similar or distinct phenomena. Purpose To determine the relationships between common vestibular tests including the King-Devick (K-D) test, Sensory Organization Test (SOT), Head Shake-Sensory Organization Test (HS-SOT), and Dynamic Visual Acuity (DVA) test, when administered contiguously, to healthy recreational athletes aged 14 to 24 years. Study Design This study used a prospective design to evaluate relationships between the K-D, SOT, HS-SOT, and DVA tests in 60 healthy individuals. Methods Sixty participants (30 males, 30 females; mean age, 19.9 ± 3.74 years) completed the four tests in a single testing session. Results Results did not support a relationship between any pair of the K-D, SOT, HS-SOT, and DVA tests. Pearson correlations between tests were poor, ranging from 0.14 to 0.20. As expected the relationship between condition 2 of the SOT and HS-SOT fixed was strong (ICC=0.81) as well as condition 5 of the SOT with HS-SOT sway (ICC=0.78). The test-retest reliability of all 4 tests was evaluated to ensure the relationships of the 4 tests were consistent between test trials and reliability was excellent with intraclass correlations ranging from 0.79 to 0.97. Conclusions The lack of relationships in these tests is clinically important because it suggests that the tests evaluate different aspects of visual and vestibular function. Further, these results suggest that a comprehensive assessment of visual and vestibular deficits following concussion may require a multifaceted approach. Level of Evidence 2b: Individual Cohort Study. PMID:28900564

  5. The phosphorylation status of merlin in sporadic vestibular Schwannomas.

    Science.gov (United States)

    Wang, Zhaoyan; Lu, Yanjun; Tang, Juanjuan; Wang, Haojie; Wu, Hao

    2009-04-01

    The events leading to Schwannomas development are still largely unknown. Some studies have demonstrated that merlin acts as a tumor suppressor by blocking Ras-mediated signaling. In this study, we analyze the clinical and biological behaviors of seven randomly selected sporadic vestibular Schwannomas removed from the patients. We find that merlin was commonly lost in these Schwannomas, due to loss of merlin expression or phosphorylation status of merlin expression. Heightened CDKs/cyclins signal transduction concomitant with loss of p27 was well correlated with loss of functional merlin in Schwannomas. More, we show that phosphorylated merlin Schwannomas exhibited increased Ras/Rac/PAK signal transduction. That was in agreement with the severe clinical behaviors, i.e., phosphorylation status of merlin increased tumor size in sporadic vestibular Schwannomas. These results led us to suggest that phosphorylated merlin, a kind of type of mutation merlin, is involved in tumorigenesis of sporadic vestibular Schwannomas.

  6. Effects of vestibular rehabilitation in the elderly complaining of dizziness

    Directory of Open Access Journals (Sweden)

    Andréa Paz-Oliveira

    2014-08-01

    Full Text Available Changes of body balance are among the most common complaints of the elderly. Vestibular rehabilitation is one of the most effective methods in the recovery of the body balance. The objective to investigate the effects of vestibular rehabilitation in body balance of a group of elderly people with dizziness complain through dizziness handicap inventory. The sample was comprised of 10 seniors (6 women and 4 men with mean age of 68.9 years. The elderly complaining of dizziness showed high score in the DHI in the physical, functional and emotional aspects in the condition pre-VR and these values decreased after vestibular rehabilitation program. Complaints of dizziness also decreased after the implementation of the programmee.  

  7. Internal models and neural computation in the vestibular system.

    Science.gov (United States)

    Green, Andrea M; Angelaki, Dora E

    2010-01-01

    The vestibular system is vital for motor control and spatial self-motion perception. Afferents from the otolith organs and the semicircular canals converge with optokinetic, somatosensory and motor-related signals in the vestibular nuclei, which are reciprocally interconnected with the vestibulocerebellar cortex and deep cerebellar nuclei. Here, we review the properties of the many cell types in the vestibular nuclei, as well as some fundamental computations implemented within this brainstem-cerebellar circuitry. These include the sensorimotor transformations for reflex generation, the neural computations for inertial motion estimation, the distinction between active and passive head movements, as well as the integration of vestibular and proprioceptive information for body motion estimation. A common theme in the solution to such computational problems is the concept of internal models and their neural implementation. Recent studies have shed new insights into important organizational principles that closely resemble those proposed for other sensorimotor systems, where their neural basis has often been more difficult to identify. As such, the vestibular system provides an excellent model to explore common neural processing strategies relevant both for reflexive and for goal-directed, voluntary movement as well as perception.

  8. The role of stereo vision in visual-vestibular integration.

    Science.gov (United States)

    Butler, John S; Campos, Jennifer L; Bülthoff, Heinrich H; Smith, Stuart T

    2011-01-01

    Self-motion through an environment stimulates several sensory systems, including the visual system and the vestibular system. Recent work in heading estimation has demonstrated that visual and vestibular cues are typically integrated in a statistically optimal manner, consistent with Maximum Likelihood Estimation predictions. However, there has been some indication that cue integration may be affected by characteristics of the visual stimulus. Therefore, the current experiment evaluated whether presenting optic flow stimuli stereoscopically, or presenting both eyes with the same image (binocularly) affects combined visual-vestibular heading estimates. Participants performed a two-interval forced-choice task in which they were asked which of two presented movements was more rightward. They were presented with either visual cues alone, vestibular cues alone or both cues combined. Measures of reliability were obtained for both binocular and stereoscopic conditions. Group level analyses demonstrated that when stereoscopic information was available there was clear evidence of optimal integration, yet when only binocular information was available weaker evidence of cue integration was observed. Exploratory individual analyses demonstrated that for the stereoscopic condition 90% of participants exhibited optimal integration, whereas for the binocular condition only 60% of participants exhibited results consistent with optimal integration. Overall, these findings suggest that stereo vision may be important for self-motion perception, particularly under combined visual-vestibular conditions.

  9. Long-term mobile phone use and the risk of vestibular schwannoma: a Danish nationwide cohort study

    DEFF Research Database (Denmark)

    Schüz, Joachim; Steding-Jessen, Marianne; Hansen, Søren

    2011-01-01

    Vestibular schwannomas grow in the region within the brain where most of the energy by radiofrequency electromagnetic fields from using mobile phones is absorbed. The authors used 2 Danish nationwide cohort studies, one a study of all adult Danes subscribing for a mobile phone in 1995 or earlier...... and one on sociodemographic factors and cancer risk, and followed subjects included in both cohorts for occurrence of vestibular schwannoma up to 2006 inclusively. In this study including 2.9 million subjects, a long-term mobile phone subscription of =11 years was not related to an increased vestibular...... reported holding their mobile phone to the right ear. Vestibular schwannomas in long-term male subscribers were not of larger size than expected. Overall, no evidence was found that mobile phone use is related to the risk of vestibular schwannoma. Because of the usually slow growth of vestibular schwannoma...

  10. Long-term mobile phone use and the risk of vestibular schwannoma: a Danish nationwide cohort study

    DEFF Research Database (Denmark)

    Schüz, Joachim; Steding-Jessen, Marianne; Hansen, Søren

    2011-01-01

    Vestibular schwannomas grow in the region within the brain where most of the energy by radiofrequency electromagnetic fields from using mobile phones is absorbed. The authors used 2 Danish nationwide cohort studies, one a study of all adult Danes subscribing for a mobile phone in 1995 or earlier...... and one on sociodemographic factors and cancer risk, and followed subjects included in both cohorts for occurrence of vestibular schwannoma up to 2006 inclusively. In this study including 2.9 million subjects, a long-term mobile phone subscription of ≥11 years was not related to an increased vestibular...... reported holding their mobile phone to the right ear. Vestibular schwannomas in long-term male subscribers were not of larger size than expected. Overall, no evidence was found that mobile phone use is related to the risk of vestibular schwannoma. Because of the usually slow growth of vestibular schwannoma...

  11. Preliminary evidence of improved cognitive performance following vestibular rehabilitation in children with combined ADHD (cADHD) and concurrent vestibular impairment.

    Science.gov (United States)

    Lotfi, Younes; Rezazadeh, Nima; Moossavi, Abdollah; Haghgoo, Hojjat Allah; Rostami, Reza; Bakhshi, Enayatollah; Badfar, Faride; Moghadam, Sedigheh Farokhi; Sadeghi-Firoozabadi, Vahid; Khodabandelou, Yousef

    2017-12-01

    Balance function has been reported to be worse in ADHD children than in their normal peers. The present study hypothesized that an improvement in balance could result in better cognitive performance in children with ADHD and concurrent vestibular impairment. This study was designed to evaluate the effects of comprehensive vestibular rehabilitation therapy on the cognitive performance of children with combined ADHD and concurrent vestibular impairment. Subject were 54 children with combined ADHD. Those with severe vestibular impairment (n=33) were randomly assigned to two groups that were matched for age. A rehabilitation program comprising overall balance and gate, postural stability, and eye movement exercises was assigned to the intervention group. Subjects in the control group received no intervention for the same time period. Intervention was administered twice weekly for 12 weeks. Choice reaction time (CRT) and spatial working memory (SWM) subtypes of the Cambridge Neuropsychological Test Automated Battery (CANTAB) were completed pre- and post-intervention to determine the effects of vestibular rehabilitation on the cognitive performance of the subjects with ADHD and concurrent vestibular impairment. ANCOVA was used to compare the test results of the intervention and control group post-test. The percentage of correct trial scores for the CRT achieved by the intervention group post-test increased significantly compared to those of the control group (p=0.029). The CRT mean latency scores were significantly prolonged in the intervention group following intervention (p=0.007) compared to the control group. No significant change was found in spatial functioning of the subjects with ADHD following 12 weeks of intervention (p>0.05). The study highlights the effect of vestibular rehabilitation on the cognitive performance of children with combined ADHD and concurrent vestibular disorder. The findings indicate that attention can be affected by early vestibular

  12. The Severity of Vestibular Dysfunction in Deafness as a Determinant of Comorbid Hyperactivity or Anxiety.

    Science.gov (United States)

    Antoine, Michelle W; Vijayakumar, Sarath; McKeehan, Nicholas; Jones, Sherri M; Hébert, Jean M

    2017-05-17

    Attention-deficit/hyperactivity disorder (ADHD) and anxiety-related disorders occur at rates 2-3 times higher in deaf compared with hearing children. Potential explanations for these elevated rates and the heterogeneity of behavioral disorders associated with deafness have usually focused on socio-environmental rather than biological effects. Children with the 22q11.2 deletion or duplication syndromes often display hearing loss and behavioral disorders, including ADHD and anxiety-related disorders. Here, we show that mouse mutants with either a gain or loss of function of the T-Box transcription factor gene, Tbx1, which lies within the 22q11.2 region and is responsible for most of the syndromic defects, exhibit inner ear defects and hyperactivity. Furthermore, we show that (1) inner ear dysfunction due to the tissue-specific loss of Tbx1 or Slc12a2, which encodes a sodium-potassium-chloride cotransporter and is also necessary for inner ear function, causes hyperactivity; (2) vestibular rather than auditory failure causes hyperactivity; and (3) the severity rather than the age of onset of vestibular dysfunction differentiates whether hyperactivity or anxiety co-occurs with inner ear dysfunction. Together, these findings highlight a biological link between inner ear dysfunction and behavioral disorders and how sensory abnormalities can contribute to the etiology of disorders traditionally considered of cerebral origin.SIGNIFICANCE STATEMENT This study examines the biological rather than socio-environmental reasons why hyperactivity and anxiety disorders occur at higher rates in deaf individuals. Using conditional genetic approaches in mice, the authors show that (1) inner ear dysfunction due to either Tbx1 or Slc12a2 mutations cause hyperactivity; (2) it is vestibular dysfunction, which frequently co-occurs with deafness but often remains undiagnosed, rather than auditory dysfunction that causes hyperactivity and anxiety-related symptoms; and (3) the severity of

  13. Intermediate Latency-Evoked Potentials of Multimodal Cortical Vestibular Areas: Galvanic Stimulation.

    Science.gov (United States)

    Kammermeier, Stefan; Singh, Arun; Bötzel, Kai

    2017-01-01

    Human multimodal vestibular cortical regions are bilaterally anterior insulae and posterior opercula, where characteristic vestibular-related cortical potentials were previously reported under acoustic otolith stimulation. Galvanic vestibular stimulation likely influences semicircular canals preferentially. Galvanic stimulation was compared to previously established data under acoustic stimulation. 14 healthy right-handed subjects, who were also included in the previous acoustic potential study, showed normal acoustic and galvanic vestibular-evoked myogenic potentials. They received 2,000 galvanic binaural bipolar stimuli for each side during EEG recording. Vestibular cortical potentials were found in all 14 subjects and in the pooled data of all subjects ("grand average") bilaterally. Anterior insula and posterior operculum were activated exclusively under galvanic stimulation at 25, 35, 50, and 80 ms; frontal regions at 30 and 45 ms. Potentials at 70 ms in frontal regions and at 110 ms at all of the involved regions could also be recorded; these events were also found using acoustic stimulation in our previous study. Galvanic semicircular canal stimulation evokes specific potentials in addition to those also found with acoustic otolith stimulation in identically located regions of the vestibular cortex. Vestibular cortical regions activate differently by galvanic and acoustic input at the peripheral sensory level. Differential effects in vestibular cortical-evoked potentials may see clinical use in specific vertigo disorders.

  14. Intermediate Latency-Evoked Potentials of Multimodal Cortical Vestibular Areas: Galvanic Stimulation

    Directory of Open Access Journals (Sweden)

    Stefan Kammermeier

    2017-11-01

    Full Text Available IntroductionHuman multimodal vestibular cortical regions are bilaterally anterior insulae and posterior opercula, where characteristic vestibular-related cortical potentials were previously reported under acoustic otolith stimulation. Galvanic vestibular stimulation likely influences semicircular canals preferentially. Galvanic stimulation was compared to previously established data under acoustic stimulation.Methods14 healthy right-handed subjects, who were also included in the previous acoustic potential study, showed normal acoustic and galvanic vestibular-evoked myogenic potentials. They received 2,000 galvanic binaural bipolar stimuli for each side during EEG recording.ResultsVestibular cortical potentials were found in all 14 subjects and in the pooled data of all subjects (“grand average” bilaterally. Anterior insula and posterior operculum were activated exclusively under galvanic stimulation at 25, 35, 50, and 80 ms; frontal regions at 30 and 45 ms. Potentials at 70 ms in frontal regions and at 110 ms at all of the involved regions could also be recorded; these events were also found using acoustic stimulation in our previous study.ConclusionGalvanic semicircular canal stimulation evokes specific potentials in addition to those also found with acoustic otolith stimulation in identically located regions of the vestibular cortex. Vestibular cortical regions activate differently by galvanic and acoustic input at the peripheral sensory level.SignificanceDifferential effects in vestibular cortical-evoked potentials may see clinical use in specific vertigo disorders.

  15. Central ocular motor disorders, including gaze palsy and nystagmus

    OpenAIRE

    Strupp, M.; Kremmyda, O.; Adamczyk, C.; N. Böttcher; Muth, C.; Yip, C. W.; Bremova, T.

    2014-01-01

    An impairment of eye movements, or nystagmus, is seen in many diseases of the central nervous system, in particular those affecting the brainstem and cerebellum, as well as in those of the vestibular system. The key to diagnosis is a systematic clinical examination of the different types of eye movements, including: eye position, range of eye movements, smooth pursuit, saccades, gaze-holding function and optokinetic nystagmus, as well as testing for the different types of nystagmus (e.g., cen...

  16. Cognitive Functioning after Medial Frontal Lobe Damage Including the Anterior Cingulate Cortex: A Preliminary Investigation

    Science.gov (United States)

    Baird, Amee; Dewar, Bonnie-Kate; Critchley, Hugo; Gilbert, Sam J.; Dolan, Raymond J.; Cipolotti, Lisa

    2006-01-01

    Two patients with medial frontal lobe damage involving the anterior cingulate cortex (ACC) performed a range of cognitive tasks, including tests of executive function and anterior attention. Both patients lesions extended beyond the ACC, therefore caution needs to be exerted in ascribing observed deficits to the ACC alone. Patient performance was…

  17. Anatomy, physiology, and physics of the peripheral vestibular system.

    Science.gov (United States)

    Kingma, H; van de Berg, R

    2016-01-01

    Many medical doctors consider vertigo and dizziness as the major, almost obligatory complaints in patients with vestibular disorders. In this chapter, we will explain that vestibular disorders result in much more diverse and complex complaints. Many of these other complaints are unfortunately often misinterpreted and incorrectly classified as psychogenic. When we really understand the function of the vestibular system, it becomes quite obvious why patients with vestibular disorders complain about a loss of visual acuity, imbalance, fear of falling, cognitive and attentional problems, fatigue that persists even when the vertigo attacks and dizziness decreases or even disappears. Another interesting new aspect in this chapter is that we explain why the function of the otolith system is so important, and that it is a mistake to focus on the function of the semicircular canals only, especially when we want to understand why some patients seem to suffer more than others from the loss of canal function as objectified by reduced caloric responses. © 2016 Elsevier B.V. All rights reserved.

  18. Neuroticism modulates brain visuo-vestibular and anxiety systems during a virtual rollercoaster task.

    Science.gov (United States)

    Riccelli, Roberta; Indovina, Iole; Staab, Jeffrey P; Nigro, Salvatore; Augimeri, Antonio; Lacquaniti, Francesco; Passamonti, Luca

    2017-02-01

    Different lines of research suggest that anxiety-related personality traits may influence the visual and vestibular control of balance, although the brain mechanisms underlying this effect remain unclear. To our knowledge, this is the first functional magnetic resonance imaging (fMRI) study that investigates how individual differences in neuroticism and introversion, two key personality traits linked to anxiety, modulate brain regional responses and functional connectivity patterns during a fMRI task simulating self-motion. Twenty-four healthy individuals with variable levels of neuroticism and introversion underwent fMRI while performing a virtual reality rollercoaster task that included two main types of trials: (1) trials simulating downward or upward self-motion (vertical motion), and (2) trials simulating self-motion in horizontal planes (horizontal motion). Regional brain activity and functional connectivity patterns when comparing vertical versus horizontal motion trials were correlated with personality traits of the Five Factor Model (i.e., neuroticism, extraversion-introversion, openness, agreeableness, and conscientiousness). When comparing vertical to horizontal motion trials, we found a positive correlation between neuroticism scores and regional activity in the left parieto-insular vestibular cortex (PIVC). For the same contrast, increased functional connectivity between the left PIVC and right amygdala was also detected as a function of higher neuroticism scores. Together, these findings provide new evidence that individual differences in personality traits linked to anxiety are significantly associated with changes in the activity and functional connectivity patterns within visuo-vestibular and anxiety-related systems during simulated vertical self-motion. Hum Brain Mapp 38:715-726, 2017. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  19. TS Fuzzy Model-Based Controller Design for a Class of Nonlinear Systems Including Nonsmooth Functions

    DEFF Research Database (Denmark)

    Vafamand, Navid; Asemani, Mohammad Hassan; Khayatiyan, Alireza

    2018-01-01

    criterion, new robust controller design conditions in terms of linear matrix inequalities are derived. Three practical case studies, electric power steering system, a helicopter model and servo-mechanical system, are presented to demonstrate the importance of such class of nonlinear systems comprising......This paper proposes a novel robust controller design for a class of nonlinear systems including hard nonlinearity functions. The proposed approach is based on Takagi-Sugeno (TS) fuzzy modeling, nonquadratic Lyapunov function, and nonparallel distributed compensation scheme. In this paper, a novel...... TS modeling of the nonlinear dynamics with signum functions is proposed. This model can exactly represent the original nonlinear system with hard nonlinearity while the discontinuous signum functions are not approximated. Based on the bounded-input-bounded-output stability scheme and L₁ performance...

  20. Migraine patients consistently show abnormal vestibular bedside tests

    Directory of Open Access Journals (Sweden)

    Eliana Teixeira Maranhão

    2015-01-01

    Full Text Available Migraine and vertigo are common disorders, with lifetime prevalences of 16% and 7% respectively, and co-morbidity around 3.2%. Vestibular syndromes and dizziness occur more frequently in migraine patients. We investigated bedside clinical signs indicative of vestibular dysfunction in migraineurs.Objective To test the hypothesis that vestibulo-ocular reflex, vestibulo-spinal reflex and fall risk (FR responses as measured by 14 bedside tests are abnormal in migraineurs without vertigo, as compared with controls.Method Cross-sectional study including sixty individuals – thirty migraineurs, 25 women, 19-60 y-o; and 30 gender/age healthy paired controls.Results Migraineurs showed a tendency to perform worse in almost all tests, albeit only the Romberg tandem test was statistically different from controls. A combination of four abnormal tests better discriminated the two groups (93.3% specificity.Conclusion Migraine patients consistently showed abnormal vestibular bedside tests when compared with controls.

  1. Systems and methods for producing metal clusters; functionalized surfaces; and droplets including solvated metal ions

    Science.gov (United States)

    Cooks, Robert Graham; Li, Anyin; Luo, Qingjie

    2017-08-01

    The invention generally relates to systems and methods for producing metal clusters; functionalized surfaces; and droplets including solvated metal ions. In certain aspects, the invention provides methods that involve providing a metal and a solvent. The methods additionally involve applying voltage to the solvated metal to thereby produce solvent droplets including ions of the metal containing compound, and directing the solvent droplets including the metal ions to a target. In certain embodiments, once at the target, the metal ions can react directly or catalyze reactions.

  2. Vestibular Dysfunction and Difficulty with Driving: Data from the 2001–2004 National Health and Nutrition Examination Surveys

    Directory of Open Access Journals (Sweden)

    Eric X. Wei

    2017-10-01

    Full Text Available Background and objectiveThere is growing understanding of the role of vestibular function in spatial navigation and orientation. Individuals with vestibular dysfunction demonstrate impaired performance on static and dynamic tests of spatial cognition, but there is sparse literature characterizing how these impairments might affect individuals in the real-world. Given the important role of visuospatial ability in driving a motor vehicle, we sought to evaluate whether individuals with vestibular dysfunction might have increased driving difficulty.Materials and methodsWe used data from the 2001–2004 National Health and Nutrition Examination Surveys to evaluate the influence of vestibular dysfunction in driving difficulty in a nationally representative sample of U.S. adults aged ≥50 years (n = 3,071. Vestibular function was measured with the modified Romberg test. Furthermore, since vestibular dysfunction is a known contributor to falls risk, we assessed whether individuals with vestibular dysfunction and concomitant driving difficulty were at an increased risk of falls.ResultsIn multivariate analyses, vestibular dysfunction was associated with a twofold increased odd of driving difficulty (odds ratio 2.16, 95% CI 1.57, 2.98. Among participants with vestibular dysfunction, concomitant driving difficulty predicted an increased risk of falls that was significantly higher than in participants with vestibular dysfunction only (odds ratio 13.01 vs. 2.91, p < 0.0001.ConclusionThis study suggests that difficulty driving may be a real-world manifestation of impaired spatial cognition associated with vestibular loss. Moreover, driving difficulty may be a marker of more severe vestibular dysfunction.

  3. Lack of biocytin transfer at gap junctions in the chicken vestibular nuclei.

    Science.gov (United States)

    Arabshahi, A; Giaume, C; Peusner, K D

    1997-06-01

    In vivo experiments were designed to test for functional gap junctions at 'mixed' synapses that were morphologically characterized between the large-diameter, primary vestibular fibers and second-order vestibular neurons in the chicken, Gallus gallus. In previous intracellular recordings and dye injections into these neurons from brain slice preparations of chick embryos (E15/16) and also newborn hatchlings (HI-2), no evidence was obtained for functional gap junctions. Therefore, biocytin, a low molecular weight tracer that permeates gap junction channels, was extracellularly applied to either the ampullary nerves or to the vestibular ganglion of 3-6 day old hatchlings and adult chickens (9 months). This procedure resulted in the uptake of the dye and heavy staining of both the thick and thin fibers composing the vestibular nerve and in loading of vestibular efferent neurons. However, no dye transfer was observed between the large-diameter, primary vestibular fibers and second-order vestibular neurons. This observation, which was performed using a relatively non-invasive approach on intact animals, suggests that the gap junctions at these mixed synapses are probably not functional under the conditions of these experiments.

  4. Vibration-induced nystagmus in patients with vestibular schwannoma: Characteristics and clinical implications.

    Science.gov (United States)

    Lee, Jeon Mi; Kim, Mi Joo; Kim, Jin Won; Shim, Dae Bo; Kim, Jinna; Kim, Sung Huhn

    2017-07-01

    To investigate the clinical significance of vibration-induced nystagmus (VIN) in unilateral vestibular asymmetry and vestibular schwannoma. Thirteen patients with vestibular schwannoma underwent the VIN test, in which stimulation was applied to the mastoid processes and sternocleidomastoid (SCM) muscles on the ipsilateral and contralateral sides of lesions. Preoperative VIN was measured, and changes in VIN were followed up for 6months after tumor removal. Significance of VIN was determined by evaluation of its sensitivity, correlation with vestibular function tests and tumor volume, and postoperative changes. The overall pre and postoperative sensitivities of VIN were 92.3% and 100%, respectively, considering stimulation at all four sites. Maximum slow-phase velocity (MSPV) of VIN was linearly correlated with caloric weakness and tumor volume, especially when stimulation was applied to the SCM muscle. Postoperative MSPV of VIN exhibited stronger linear correlation with postoperative changes in canal paresis value and inverse correlation with tumor size upon stimulation of the ipsilateral SCM muscle than upon stimulation of other sites. During the 6-month follow-up period, persistence of VIN without changes in MSPV was observed even after vestibular compensation. Evoking VIN by stimulation of the mastoid processes and SCM muscles is effective for detecting vestibular asymmetry. It could also help determine the degree of vestibular asymmetry and volume of vestibular schwannoma if stimulation is applied to the SCM muscle. The results of this study could provide clues for the basic application of VIN in patients with vestibular loss and vestibular schwannoma. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  5. Linear accelerator-based stereotactic radiosurgery for bilateral vestibular schwannomas in patients with neurofibromatosis type 2

    NARCIS (Netherlands)

    Meijer, Otto W. M.; Vandertop, W. Peter; Lagerwaard, Frank J.; Slotman, Ben J.

    2008-01-01

    OBJECTIVE: Patients with neurofibromatosis Type 2 (NF2) patients typically have bilateral vestibular schwannomas (VS) and are at risk for developing bilateral deafness, bilateral trigeminal, and bilateral facial nerve function loss. Previous reports suggested that treatment outcomes in these

  6. Neurosonology Accuracy for Isolated Acute Vestibular Syndromes.

    Science.gov (United States)

    Tábuas-Pereira, Miguel; Sargento-Freitas, João; Isidoro, Luís; Silva, Fernando; Galego, Orlando; Nunes, César; Cordeiro, Gustavo; Cunha, Luís

    2017-12-01

    The clinical approach to acute vestibular syndromes is often complex for the physician. Neurosonology offers a noninvasive method to study the cervicocephalic circulation when a vascular etiology is suspected. We aim to evaluate the diagnostic accuracy of a vascular neurosonological exam in isolated acute vestibular syndrome. All patients submitted to cerebrovascular ultrasound and magnetic resonance imaging during the period between 2011 and 2015 with acute isolated vestibular syndrome. Those with any clinical sign of brainstem lesion on presentation were excluded. All patients performed the neuroimaging study (brain computed tomography and magnetic resonance imaging) and neurologic surveillance. Neurosonological exam included all intra- and extracranial segments of the vertebrobasilar circulation. Positive ultrasound exam was defined as the presence of stenotic or occlusive disease in any of these segments related to the infarcted area. A total of 108 patients were included: 60 (53.6%) were males (mean age: 60.75 years (standard deviation, 14.17)). In 27 patients (25.0%) a cerebral ischemic lesion was found to be the cause of the vertigo. Neurosonological assessment showed a sensitivity of 40.7% (95% confidence interval (CI): 22.4; 61.2), specificity of 100% (95% CI: 95.5; 100.0), positive predictive value (PPV) of 100% (95% CI: 71.5; 100.0), and negative predictive value (NPV) of 83.5% (95% CI: 74.6; 90.3). Our study suggests that cerebrovascular ultrasound is a highly specific method for the diagnosis of cerebrovascular vertigo. However, its low sensitivity makes it a poor candidate for screening. © 2017 by the American Institute of Ultrasound in Medicine.

  7. Negative emotional stimuli enhance vestibular processing.

    Science.gov (United States)

    Preuss, Nora; Ellis, Andrew W; Mast, Fred W

    2015-08-01

    Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports, and erotic pictures. Using a Bayesian hierarchical approach, we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral/positive objects. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information. (c) 2015 APA, all rights reserved).

  8. A hybrid version of the SCAN functional including long-range dispersion interactions

    Science.gov (United States)

    Ko, Hsin-Yu; Calegari Andrade, Marcos F.; Santra, Biswajit; Selloni, Annabella; Car, Roberto

    The recently developed meta-GGA density functional, called SCAN (strongly constrained and appropriately normed), provides an accurate description of the electronic structure in a broad class of systems characterized by different bonding interactions, including intermediate range van-der-Waals (vdW) bonding. Here we consider a hybrid version of the SCAN functional with inclusion of long-range vdW interactions via a re-parameterized Tkatchenko-Scheffler scheme. Calculations for the S22 molecular database, ice hexamer clusters, and bulk ice Ih indicate that this functional further improves the description of vdW and hydrogen bonding interactions. This work has been supported by the Department of Energy under Grants No. DE-SC0008626.

  9. Gait ataxia in humans: vestibular and cerebellar control of dynamic stability.

    Science.gov (United States)

    Schniepp, Roman; Möhwald, Ken; Wuehr, Max

    2017-10-01

    During human locomotion, vestibular feedback control is fundamental for maintaining dynamic stability and adapting the gait pattern to external circumstances. Within the supraspinal locomotor network, the cerebellum represents the key site for the integration of vestibular feedback information. The cerebellum is further important for the fine-tuning and coordination of limb movements during walking. The aim of this review article is to highlight the shared structural and functional sensorimotor principles in vestibular and cerebellar locomotion control. Vestibular feedback for the maintenance of dynamic stability is integrated into the locomotor pattern via midline, caudal cerebellar structures (vermis, flocculonodular lobe). Hemispheric regions of the cerebellum facilitate feed-forward control of multi-joint coordination and higher locomotor functions. Characteristic features of the gait disorder in patients with vestibular deficits or cerebellar ataxia are increased levels of spatiotemporal gait variability in the fore-aft and the medio-lateral gait dimension. In the fore-aft dimension, pathologic increases of gait fluctuations critically depend on the locomotion speed and predominantly manifest during slow walking velocities. This feature is associated with an increased risk of falls in both patients with vestibular hypofunction as well as patients with cerebellar ataxia. Pharmacological approaches for the treatment of vestibular or cerebellar gait ataxia are currently not available. However, new promising options are currently tested in randomized, controlled trials (fampridine/FACEG; acetyl-DL-leucine/ALCAT).

  10. Afferent diversity and the organization of central vestibular pathways.

    Science.gov (United States)

    Goldberg, J M

    2000-02-01

    This review considers whether the vestibular system includes separate populations of sensory axons innervating individual organs and giving rise to distinct central pathways. There is a variability in the discharge properties of afferents supplying each organ. Discharge regularity provides a marker for this diversity since fibers which differ in this way also differ in many other properties. Postspike recovery of excitability determines the discharge regularity of an afferent and its sensitivity to depolarizing inputs. Sensitivity is small in regularly discharging afferents and large in irregularly discharging afferents. The enhanced sensitivity of irregular fibers explains their larger responses to sensory inputs, to efferent activation, and to externally applied galvanic currents, but not their distinctive response dynamics. Morphophysiological studies show that regular and irregular afferents innervate overlapping regions of the vestibular nuclei. Intracellular recordings of EPSPs reveal that some secondary vestibular neurons receive a restricted input from regular or irregular afferents, but that most such neurons receive a mixed input from both kinds of afferents. Anodal currents delivered to the labyrinth can result in a selective and reversible silencing of irregular afferents. Such a functional ablation can provide estimates of the relative contributions of regular and irregular inputs to a central neuron's discharge. From such estimates it is concluded that secondary neurons need not resemble their afferent inputs in discharge regularity or response dynamics. Several suggestions are made as to the potentially distinctive contributions made by regular and irregular afferents: (1) Reflecting their response dynamics, regular and irregular afferents could compensate for differences in the dynamic loads of various reflexes or of individual reflexes in different parts of their frequency range; (2) The gating of irregular inputs to secondary VOR neurons could

  11. Visual and Postural Motion-Evoked Dizziness Symptoms Are Predominant in Vestibular Migraine Patients.

    Science.gov (United States)

    Vuralli, Doga; Yildirim, Funuzar; Akcali, Didem T; Ilhan, Mustafa N; Goksu, Nebil; Bolay, Hayrunnisa

    2018-01-01

    Vestibular migraine (VM) is one of the most common underdiagnosed disorders. We aimed to study the clinical characteristics of VM patients who were referred to a neurology-headache unit by otolaryngology after exclusion of peripheral causes of vertigo. One hundred and one patients diagnosed with VM in the headache unit were included. Description of vestibular symptoms, demographic and clinical features, trigger factors, accompanying diseases, and response to vestibular-suppressant medications and prophylactic migraine treatment were evaluated. Vestibular symptoms were triggered by daily head and body movements and mainly consisted of brief attacks lasting seconds (60.4% of patients) although the total duration of the vestibular episode lasted hours or days. Other aggravating factors were moving visual stimuli, passive motion, and visually busy environments. Visually induced vestibular symptoms were defined by 71.3% of the patients, and positional motion-induced vestibular symptoms were described by 82.2% of the patients. Vestibular symptoms were mainly defined as feeling the ground slipping from under their feet (40.6%), feeling like there is an earthquake or swaying (27.7%), sensation of rocking on a boat (26.7%), and sensation as if stepping on empty space (24.8%). The majority of the patients (83.2%) previously used vestibular-suppressant drugs, and these drugs were effective temporarily only in 12.9%. Chronic recurrent dizziness symptoms, rather than internal or external vertigo, are predominant in our VM patients. Recurrent brief dizziness attacks induced upon routine visual and/or postural motion, longstanding symptoms with limited response to vestibular suppressants, and precipitation by typical migraine triggers are suggestive of VM.

  12. Vestibular evoked myogenic potentials: an overview Potencial evocado miogênico vestibular: uma visão geral

    Directory of Open Access Journals (Sweden)

    Renato Cal

    2009-06-01

    Full Text Available The vestibular evoked myogenic potential (VEMP test is a relatively new diagnostic tool that is in the process of being investigated in patients with specific vestibular disorders. Briefly, the VEMP is a biphasic response elicited by loud clicks or tone bursts recorded from the tonically contracted sternocleidomastoid muscle, being the only resource available to assess the function of the saccule and the lower portion of the vestibular nerve. AIM: In this review, we shall highlight the history, methods, current VEMP status, and discuss its specific application in the diagnosis of the Ménière's Syndrome.O teste do potencial evocado miogênico vestibular (PEMV é um instrumento diagnóstico relativamente novo e ainda em processo de validação em estudos com pacientes portadores de desordens vestibulares específicas. De forma resumida, o PEMV é uma resposta bifásica em resposta a estímulos sonoros gravados a partir de contrações do músculo esternocleidomastóideo e é o único recurso existente para avaliar a função do sáculo e da divisão inferior do nervo vestibular. OBJETIVO: Nesta revisão iremos destacar a história, método de realização, situação atual da pesquisa envolvendo o PEMV, além de discutir as suas aplicações específicas no diagnóstico da síndrome de Ménière.

  13. Highly conserved molecular pathways, including Wnt signaling, promote functional recovery from spinal cord injury in lampreys.

    Science.gov (United States)

    Herman, Paige E; Papatheodorou, Angelos; Bryant, Stephanie A; Waterbury, Courtney K M; Herdy, Joseph R; Arcese, Anthony A; Buxbaum, Joseph D; Smith, Jeramiah J; Morgan, Jennifer R; Bloom, Ona

    2018-01-15

    In mammals, spinal cord injury (SCI) leads to dramatic losses in neurons and synaptic connections, and consequently function. Unlike mammals, lampreys are vertebrates that undergo spontaneous regeneration and achieve functional recovery after SCI. Therefore our goal was to determine the complete transcriptional responses that occur after SCI in lampreys and to identify deeply conserved pathways that promote regeneration. We performed RNA-Seq on lamprey spinal cord and brain throughout the course of functional recovery. We describe complex transcriptional responses in the injured spinal cord, and somewhat surprisingly, also in the brain. Transcriptional responses to SCI in lampreys included transcription factor networks that promote peripheral nerve regeneration in mammals such as Atf3 and Jun. Furthermore, a number of highly conserved axon guidance, extracellular matrix, and proliferation genes were also differentially expressed after SCI in lampreys. Strikingly, ~3% of differentially expressed transcripts belonged to the Wnt pathways. These included members of the Wnt and Frizzled gene families, and genes involved in downstream signaling. Pharmacological inhibition of Wnt signaling inhibited functional recovery, confirming a critical role for this pathway. These data indicate that molecular signals present in mammals are also involved in regeneration in lampreys, supporting translational relevance of the model.

  14. Effects of vestibular rehabilitation and social reinforcement on recovery following ablative vestibular surgery.

    Science.gov (United States)

    Mruzek, M; Barin, K; Nichols, D S; Burnett, C N; Welling, D B

    1995-07-01

    This study investigated the relative effects of vestibular rehabilitation (VR) and social reinforcement (SR) on recovery following ablative vestibular surgery. Twenty-four subjects were randomly assigned to three treatment groups of either VR with SR, VR without SR, or general range of motion (ROM) exercises with SR. Outcome measures included equilibrium scores in dynamic posturography, asymmetry index in rotation testing, motion sensitivity quotient (MSQ), and dizziness handicap inventory (DHI). A multiple comparison of the overall outcome measures showed no significant differences in group performance over an 8-week period. When individual outcome measures were compared, MSQ and DHI results at the end of the 8-week treatment period revealed less motion sensitivity and dizziness handicap in groups who received VR, with or without SR, as compared with the group who received ROM exercises. These results suggest that after a vestibular injury most patients can effectively utilize central compensation mechanisms to recover from such an injury, regardless of the type of therapeutic intervention used. On the other hand, the reduction in motion sensitivity and dizziness handicap for patients who received VR could indicate a more rapid and complete recovery for these patients. This investigation is continuing as a long-term follow-up study to determine whether there are any long-term benefits in participating in a VR program.

  15. Perspectival Structure and Vestibular Processing

    DEFF Research Database (Denmark)

    Alsmith, Adrian John Tetteh

    2016-01-01

    I begin by contrasting a taxonomic approach to the vestibular system with the structural approach I take in the bulk of this commentary. I provide an analysis of perspectival structure. Employing that analysis and following the structural approach, I propose three lines of empirical investigation...

  16. Development of Vestibular Stochastic Resonance as a Sensorimotor Countermeasure: Improving Otolith Ocular and Motor Task Responses

    Science.gov (United States)

    Mulavara, Ajitkumar; Fiedler, Matthew; DeDios,Yiri E.; Galvan, Raquel; Bloomberg, Jacob; Wood, Scott

    2011-01-01

    Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Stochastic resonance (SR) is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. The goal of our present study is to develop a countermeasure based on vestibular SR that could improve central interpretation of vestibular input and improve motor task responses to mitigate associated risks.

  17. Achados vestibulares em usuários de aparelho de amplificação sonora individual Vestibular findings in hearing aid users

    Directory of Open Access Journals (Sweden)

    Fabiane Paulin

    2009-01-01

    patients, 18 (90% showed tinnitus complaint, 15 (75% dizziness complaint and eight (40% headache complaint; b There was a prevalence of alterations in the caloric test and in the peripheral vestibular system; c the results of the vestibular exam showed alterations in 14 patients (70% being, eight cases (40% of peripheral vestibular irritative syndromes and six cases (30% of peripheral vestibular deficiency syndromes; d we verified significant difference between the vestibular exam results and how long the patient had use the hearing aid; e from the five patients that did not related vestibular symptoms four (80% showed alterations in the vestibular exam. CONCLUSION: the importance and sensibility of the functional study regarding the balance system in this type of population must be emphasized because same disorders may occur in the vestibular exam in spite of symptom presence.

  18. Mechanotransduction and hyperpolarization-activated currents contribute to spontaneous activity in mouse vestibular ganglion neurons

    Science.gov (United States)

    Horwitz, Geoffrey C.; Risner-Janiczek, Jessica R.

    2014-01-01

    The hyperpolarization-activated, cyclic nucleotide–sensitive current, Ih, is present in vestibular hair cells and vestibular ganglion neurons, and is required for normal balance function. We sought to identify the molecular correlates and functional relevance of Ih in vestibular ganglion neurons. Ih is carried by channels consisting of homo- or heteromeric assemblies of four protein subunits from the Hcn gene family. The relative expression of Hcn1–4 mRNA was examined using a quantitative reverse transcription PCR (RT-PCR) screen. Hcn2 was the most highly expressed subunit in vestibular neuron cell bodies. Immunolocalization of HCN2 revealed robust expression in cell bodies of all vestibular ganglion neurons. To characterize Ih in vestibular neuron cell bodies and at hair cell–afferent synapses, we developed an intact, ex vivo preparation. We found robust physiological expression of Ih in 89% of cell bodies and 100% of calyx terminals. Ih was significantly larger in calyx terminals than in cell bodies; however, other biophysical characteristics were similar. Ih was absent in calyces lacking Hcn1 and Hcn2, but small Ih was still present in cell bodies, which suggests expression of an additional subunit, perhaps Hcn4. To determine the contributions of hair cell mechanotransduction and Ih to the firing patterns of calyx terminals, we recorded action potentials in current-clamp mode. Mechanotransduction currents were modulated by hair bundle defection and application of calcium chelators to disrupt tip links. Ih activity was modulated using ZD7288 and cAMP. We found that both hair cell transduction and Ih contribute to the rate and regularity of spontaneous action potentials in the vestibular afferent neurons. We propose that modulation of Ih in vestibular ganglion neurons may provide a mechanism for modulation of spontaneous activity in the vestibular periphery. PMID:24638995

  19. Vestibular Findings in Military Band Musicians

    Directory of Open Access Journals (Sweden)

    Zeigelboim, Bianca Simone

    2014-04-01

    Full Text Available Introduction Exposure to music is the subject of many studies because it is related to an individual's professional and social activities. Objectives Evaluate the vestibular behavior in military band musicians. Methods A retrospective cross-sectional study was performed. Nineteen musicians with ages ranging from 21 to 46 years were evaluated (average = 33.7 years and standard deviation = 7.2 years. They underwent anamnesis and vestibular and otolaryngologic evaluation through vectoelectronystagmography. Results The most evident otoneurologic symptoms in the anamnesis were tinnitus (84.2%, hearing difficulties (47.3%, dizziness (36.8%, headache (26.3%, intolerance to intense sounds (21.0%, and earache (15.7%. Seven musicians (37.0% showed vestibular abnormality, which occurred in the caloric test. The abnormality was more prevalent in the peripheral vestibular system, and there was a predominance of irritative peripheral vestibular disorders. Conclusion The alteration in vestibular exam occurred in the caloric test (37.0%. There were changes in the prevalence of peripheral vestibular system with a predominance of irritative vestibular dysfunction. Dizziness was the most significant symptom for the vestibular test in correlation with neurotologic symptoms. The present study made it possible to verify the importance of the labyrinthine test, which demonstrates that this population should be better studied because the systematic exposure to high sound pressure levels may cause major vestibular alterations.

  20. Vestibular findings in military band musicians.

    Science.gov (United States)

    Zeigelboim, Bianca Simone; Gueber, Crislaine; Silva, Thanara Pruner da; Liberalesso, Paulo Breno Noronha; Gonçalves, Claudia Giglio de Oliveira; Faryniuk, João Henrique; Marques, Jair Mendes; Jurkiewicz, Ari Leon

    2014-04-01

    Introduction Exposure to music is the subject of many studies because it is related to an individual's professional and social activities. Objectives Evaluate the vestibular behavior in military band musicians. Methods A retrospective cross-sectional study was performed. Nineteen musicians with ages ranging from 21 to 46 years were evaluated (average = 33.7 years and standard deviation = 7.2 years). They underwent anamnesis and vestibular and otolaryngologic evaluation through vectoelectronystagmography. Results The most evident otoneurologic symptoms in the anamnesis were tinnitus (84.2%), hearing difficulties (47.3%), dizziness (36.8%), headache (26.3%), intolerance to intense sounds (21.0%), and earache (15.7%). Seven musicians (37.0%) showed vestibular abnormality, which occurred in the caloric test. The abnormality was more prevalent in the peripheral vestibular system, and there was a predominance of irritative peripheral vestibular disorders. Conclusion The alteration in vestibular exam occurred in the caloric test (37.0%). There were changes in the prevalence of peripheral vestibular system with a predominance of irritative vestibular dysfunction. Dizziness was the most significant symptom for the vestibular test in correlation with neurotologic symptoms. The present study made it possible to verify the importance of the labyrinthine test, which demonstrates that this population should be better studied because the systematic exposure to high sound pressure levels may cause major vestibular alterations.

  1. Mechanisms of vestibular compensation: recent advances.

    Science.gov (United States)

    Dutia, Mayank B

    2010-10-01

    This article reviews recent studies that have provided experimental evidence for mechanisms of neural and synaptic plasticity in the brain during vestibular compensation, the behavioural recovery that takes place following peripheral vestibular lesions. First, experimental evidence from animal studies indicates that an unbalanced vestibular commissural system is a fundamental cause of the syndrome of oculomotor and postural deficits after unilateral labyrinthectomy. Second, recent studies suggest the involvement of both GABAergic and glycinergic commissural neurons. In addition gliosis and reactive neurogenesis in the ipsilesional vestibular nuclei appear to be involved in compensation. Third, evidence from cerebellar-deficient mutant mice demonstrates an important role for cerebellum-dependent motor learning in the longer term. Factors such as stress steroids and neuromodulators such as histamine influence these plasticity mechanisms and may thus contribute to the development of compensation in patients. Vestibular compensation involves multiple, parallel plastic processes at various sites in the brain. Experimental evidence suggests that adaptive changes in the sensitivity of ipsilesional vestibular neurons to the inhibitory neurotransmitters GABA and glycine, changes in the electrophysiological excitability of vestibular neurons, changes in the inhibitory control of the brainstem vestibular networks by the cerebellum, gliosis and neurogenesis in the ipsilesional vestibular nuclei, and activity-dependent reorganization of the synaptic connectivity of the vestibular pathways are mechanisms involved in compensation.

  2. Vestibular nucleus neurons respond to hindlimb movement in the decerebrate cat.

    Science.gov (United States)

    Arshian, Milad S; Hobson, Candace E; Catanzaro, Michael F; Miller, Daniel J; Puterbaugh, Sonya R; Cotter, Lucy A; Yates, Bill J; McCall, Andrew A

    2014-06-15

    The vestibular nuclei integrate information from vestibular and proprioceptive afferents, which presumably facilitates the maintenance of stable balance and posture. However, little is currently known about the processing of sensory signals from the limbs by vestibular nucleus neurons. This study tested the hypothesis that limb movement is encoded by vestibular nucleus neurons and described the changes in activity of these neurons elicited by limb extension and flexion. In decerebrate cats, we recorded the activity of 70 vestibular nucleus neurons whose activity was modulated by limb movements. Most of these neurons (57/70, 81.4%) encoded information about the direction of hindlimb movement, while the remaining neurons (13/70, 18.6%) encoded the presence of hindlimb movement without signaling the direction of movement. The activity of many vestibular nucleus neurons that responded to limb movement was also modulated by rotating the animal's body in vertical planes, suggesting that the neurons integrated hindlimb and labyrinthine inputs. Neurons whose firing rate increased during ipsilateral ear-down roll rotations tended to be excited by hindlimb flexion, whereas neurons whose firing rate increased during contralateral ear-down tilts were excited by hindlimb extension. These observations suggest that there is a purposeful mapping of hindlimb inputs onto vestibular nucleus neurons, such that integration of hindlimb and labyrinthine inputs to the neurons is functionally relevant. Copyright © 2014 the American Physiological Society.

  3. Vestibular Involvement in Patients With Otitis Media With Antineutrophil Cytoplasmic Antibody-associated Vasculitis.

    Science.gov (United States)

    Morita, Yuka; Takahashi, Kuniyuki; Izumi, Shuji; Kubota, Yamato; Ohshima, Shinsuke; Horii, Arata

    2017-01-01

    Otitis media (OM) with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (OMAAV) is a novel concept of ear disease that is characterized by progressive mixed or sensorineural hearing loss with occasional systemic involvement. Considering the accumulating knowledge about the characteristics of and treatment for auditory dysfunction in OMAAV, the objective of this study was to investigate the vestibular function and symptoms of patients with OMAAV. Retrospective chart review. University hospital. Thirty-one OMAAV patients met criteria proposed by the OMAAV study group in Japan. Clinical characteristics and vestibular tests. Eleven of 31 OMAAV patients had vestibular symptoms; 3 patients had acute vertigo attack with sudden hearing loss and 8 patients had chronic dizziness. Episodic vertigo was not seen in any of the patients. Three patients who received a less intensive therapy without immunosuppressive agents developed intractable persistent dizziness. All symptomatic patients and six of the nine OMAAV patients without vestibular symptoms showed unilateral or bilateral caloric weakness; therefore, vestibular involvement was present in 84% of OMAAV patients. Gain of vestibulo-ocular reflex was reduced in symptomatic patients. The eye-tracking test and optokinetic nystagmus revealed no evidence of central dysfunction. Vestibular dysfunction was seen in 84% of OMAAV patients. One-third of OMAAV patients showed vestibular symptoms such as acute vertigo attack or chronic dizziness, which are of peripheral origin. One-third of the symptomatic patients developed intractable dizziness. Initial intensive treatment by combination therapy with steroid and immunosuppressive agents may be essential for preventing the development of intractable dizziness.

  4. Evaluation of Cervical Vestibular Evoked Myogenic Potential in Subjects with Chronic Noise Exposure.

    Science.gov (United States)

    Abd El Salam, Nehal Mamdouh; Ismail, Elshahat Ibrahem; El Saeed El Sharabasy, Ayman

    2017-12-14

    Noise has been recognized as a major cause of cochlear damage resulting in both tinnitus and hearing loss. On the other hand, damage to the vestibular system, especially the saccule, can be considered as a potential problem. The cervical vestibular-evoked myogenic potentials (cVEMPs) have been established as a clinical test of measuring both sac-cular and inferior vestibular nerve function. Therefore, it is thought to be sensitive to the noise-induced damage to the vestibular system. Accordingly, this study was designed to assess the vestibular system in subjects exposed to noise during work by using cVEMPs. This study was performed in over 60 adult males who were divided into a study group (consisting of 40 adult males) with history of chronic occupational noise exposure and with variable degree of hearing levels and a control group consisting of 20 healthy adults with normal peripheral hearing, with no history of noise exposure and no vestibular complaints. cVEMP recordings were elicited using 95dB nHL click stimuli. There was statistically significant prolonged cVEMP latency of the P13 and N23 waves of the study versus the control groups. As regard to the sense of imbalance, there were significant prolonged cVEMPs latencies in present versus absent sense of imbalance. However, there were statistically insignificant reduced cVEMP amplitudes in present versus absent sense of imbalance. Chronic noise exposure damages the vestibular system especially the saccule in addition to cochlear damage.

  5. Laboratory examinations for the vestibular system.

    Science.gov (United States)

    van de Berg, Raymond; Rosengren, Sally; Kingma, Herman

    2018-02-01

    In the last decades, researchers suggested that clinical assessment of labyrinthine function in detail became easy thanks to video head impulse tests (VHITs), vestibular evoked myogenic potential test (VEMP) and video-oculography (VOG). It has been argued that they can replace electronystagmography, the caloric and rotatory chair tests. This review addresses the latest evaluations of these tests and the opportunities they offer, but also the limitations in clinical practice. The VHIT and suppression head impulse test (SHIMP) are under ideal circumstances able to accurately identify deficits of the VOR in 3D. However, in a relevant part of the patient population, pupil tracking is inaccurate, video-goggles slip and VOR quantification is problematic. The dissociation between the VHIT and caloric test suggests that these tests are complementary. A new 3D-VOG technique claims to quantify eye torsion better than before, opening multiple diagnostic possibilities. VEMPs remain difficult to standardize. Variability in normal cervical vestibular-evoked myogenic potential amplitude is large. VEMPs become smaller or absent with age, raising questions of whether there is a lower normal limit at all. Recent research shows that the labyrinth is directly stimulated in the MRI offering new opportunities for diagnostics and research. In clinical practice, the VHIT, SHIMP, VEMP and new 3D-VOG techniques improve diagnostic power. Unfortunately, technical issues or variability prevent reliable quantitative evaluation in a part of the regular patient population. The traditional caloric and rotatory chair test can still be considered as valuable complementary tests.

  6. Galvanic vestibular stimulation speeds visual memory recall.

    Science.gov (United States)

    Wilkinson, David; Nicholls, Sophie; Pattenden, Charlotte; Kilduff, Patrick; Milberg, William

    2008-08-01

    The experiments of Alessandro Volta were amongst the first to indicate that visuo-spatial function can be altered by stimulating the vestibular nerves with galvanic current. Until recently, the beneficial effects of the procedure were masked by the high levels of electrical current applied, which induced nystagmus-related gaze deviation and spatial disorientation. However, several neuropsychological studies have shown that much weaker, imperceptible currents that do not elicit unpleasant side-effects can help overcome visual loss after stroke. Here, we show that visual processing in neurologically healthy individuals can also benefit from galvanic vestibular stimulation. Participants first learnt the names of eight unfamiliar faces and then after a short delay, answered questions from memory about how pairs of these faces differed. Mean correct reaction times were significantly shorter when sub-sensory, noise-enhanced anodal stimulation was administered to the left mastoid, compared to when no stimulation was administered at all. This advantage occurred with no loss in response accuracy, and raises the possibility that the procedure may constitute a more general form of cognitive enhancement.

  7. Hyperventilation-induced nystagmus in a large series of vestibular patients.

    Science.gov (United States)

    Califano, L; Melillo, M G; Vassallo, A; Mazzone, S

    2011-02-01

    The Hyperventilation Test is widely used in the "bed-side examination" of vestibular patients. It can either activate a latent nystagmus in central or peripheral vestibular diseases or it can interact with a spontaneous nystagmus, by reducing it or increasing it. Aims of this study were to determine the incidence, patterns and temporal characteristics of Hyperventilation-induced nystagmus in patients suffering from vestibular diseases, as well as its contribution to the differential diagnosis between vestibular neuritis and neuroma of the 8(th) cranial nerve, and its behaviour in some central vestibular diseases. The present study includes 1202 patients featuring, at vestibular examination, at least one sign of vestibular system disorders or patients diagnosed with a "Migraine-related vertigo" or "Chronic subjective dizziness". The overall incidence of Hyperventilation-induced nystagmus was 21.9%. It was detected more frequently in retrocochlear vestibular diseases rather than in end-organ vestibular diseases: 5.3% in Paroxysmal Positional Vertigo, 37.1% in Menière's disease, 37.6% in compensated vestibular neuritis, 77.2% in acute vestibular neuritis and 91.7% in neuroma of the 8(th) cranial nerve. In acute vestibular neuritis, three HVIN patterns were observed: Paretic pattern: temporary enhancement of the spontaneous nystagmus; Excitatory pattern: temporary inhibition of the spontaneous nystagmus; Strong excitatory pattern: temporary inversion of the spontaneous nystagmus. Excitatory patterns proved to be time-dependent in that they disappeared and were replaced by the paretic pattern over a period of maximum 18 days since the beginning of the disorder. In acoustic neuroma, Hyperventilation-induced nystagmus was frequently observed (91.7%), either in the form of an excitatory pattern (fast phases towards the affected site) or in the form of a paretic pattern (fast phases towards the healthy side). The direction of the nystagmus is only partially related to

  8. Unilateral Enlarged Vestibular Aqueduct Syndrome and Bilateral Endolymphatic Hydrops

    Science.gov (United States)

    Nola, Giuseppe; Sparvoli, Luca; Ralli, Giovanni

    2017-01-01

    Enlarged vestibular aqueduct (EVA) syndrome is a common congenital inner ear malformation characterized by a vestibular aqueduct with a diameter larger than 1.5 mm, mixed or sensorineural hearing loss that ranges from mild to profound, and vestibular disorders that may be present with a range from mild imbalance to episodic objective vertigo. In our study, we present the case of a patient with unilateral enlarged vestibular aqueduct and bilateral endolymphatic hydrops (EH). EH was confirmed through anamnestic history and audiological exams; EVA was diagnosed using high-resolution CT scans and MRI images. Therapy included intratympanic infusion of corticosteroids with a significant hearing improvement, more evident in the ear contralateral to EVA. Although most probably unrelated, EVA and EH may present with similar symptoms and therefore the diagnostic workup should always include the proper steps to perform a correct diagnosis. Association between progression of hearing loss and head trauma in patients with a diagnosis of EVA syndrome is still uncertain; however, these individuals should be advised to avoid activities that increase intracranial pressure to prevent further hearing deterioration. Intratympanic treatment with steroids is a safe and well-tolerated procedure that has demonstrated its efficacy in hearing, tinnitus, and vertigo control in EH. PMID:28607789

  9. Unilateral Enlarged Vestibular Aqueduct Syndrome and Bilateral Endolymphatic Hydrops

    Directory of Open Access Journals (Sweden)

    Massimo Ralli

    2017-01-01

    Full Text Available Enlarged vestibular aqueduct (EVA syndrome is a common congenital inner ear malformation characterized by a vestibular aqueduct with a diameter larger than 1.5 mm, mixed or sensorineural hearing loss that ranges from mild to profound, and vestibular disorders that may be present with a range from mild imbalance to episodic objective vertigo. In our study, we present the case of a patient with unilateral enlarged vestibular aqueduct and bilateral endolymphatic hydrops (EH. EH was confirmed through anamnestic history and audiological exams; EVA was diagnosed using high-resolution CT scans and MRI images. Therapy included intratympanic infusion of corticosteroids with a significant hearing improvement, more evident in the ear contralateral to EVA. Although most probably unrelated, EVA and EH may present with similar symptoms and therefore the diagnostic workup should always include the proper steps to perform a correct diagnosis. Association between progression of hearing loss and head trauma in patients with a diagnosis of EVA syndrome is still uncertain; however, these individuals should be advised to avoid activities that increase intracranial pressure to prevent further hearing deterioration. Intratympanic treatment with steroids is a safe and well-tolerated procedure that has demonstrated its efficacy in hearing, tinnitus, and vertigo control in EH.

  10. Quantification of Head Acceleration during Vestibular Rehabilitation Exercises.

    Science.gov (United States)

    Hogan, Anne E; Spindel, Jonathan H; Gray, Lincoln C

    2018-01-01

    Vestibular rehabilitation exercises have been proven to reduce symptoms and diminish the risk of falls in those with dizziness and balance impairments. The first purpose of this study is to investigate a new method of measuring head movements during habituation vestibular rehabilitation exercises. The second is to explore the relationship between head acceleration measurements during select traditional vestibular rehabilitation exercises and the variables of age, dizziness, and poor balance confidence. A descriptive, cross-sectional study, in a university setting. Fifty-two participants, ranging in age from 20 to 96 yr. All were volunteers, with the majority (34) reporting no history of dizziness or balance confidence. Head accelerations were calculated from linear and angular displacements as measured by magnetometry. Head accelerations decreased with increasing age, dizziness, and low balance confidence during four habituation exercises. Head acceleration varies as a function of age, dizziness, and low balance confidence during head movement-based vestibular and balance rehabilitation therapy (habituation) exercises. The magnetometry measurement method used could be applied across the course of treatment to establish predictive measures based on change in acceleration over time. More diverse participant sampling is needed to create normative data.

  11. ESTIMATING THE COBB DOUGLAS PRODUCTION FUNCTION INCLUDING THE EXPORT AND OPENNESS IN THE CASE OF ROMANIA

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    Simuț Ramona Marinela

    2015-07-01

    Full Text Available Economic convergence theories are closely related to economic growth theories. The first to study the economic growth phenomenon were the classics A. Smith, D. Ricardo, Th. Malthus, whose models of so-called classic models, do not take into account the contribution of technical progress in increasing production per capita. In order to analyze the convergence process, as a result of economic growth, a series of studies have been created to check the convergent or divergent nature of economies. Thus, in order to identify present sources of economic growth for Romania in our study we have used the Cobb-Douglas type production function. The variables that are the base of this model are represented by work factors and capital stock, to which we have added two explicative variables of economic growth: export and the openness degree of the economy. The two economic growth variables have been included in the model due to their favorable influence on the Solow residue. To estimate this production function, quarterly statistical data from the period between 2000 – first quarter and 2014 – fourth quarter have been used; the source of the data was Eurostat. As to what the first estimated model is concerned, the Cobb-Douglas production function including the export variable are both valid in Romania’s case, this have the parameters of the exogenous variables significantly different from zero, while the second estimated model, which contains the openness variable, is not valid. Its independent variable coefficient is not significantly different from zero, at the level of the entire population. This shows us that the inclusion of the degree of openness of the economy variable in the model affects the significance degree of the model and in order to validate it, the variable must be eliminated. Therefore, we can state that in Romania an increase of the openness degree of the economy due to capital imports would not generate an improvement in what type of

  12. Cochlear and Vestibular Effects of Combined Intratympanic Gentamicin and Dexamethasone.

    Science.gov (United States)

    Güneri, Enis Alpin; Olgun, Yüksel; Aslıer, Mustafa; Nuti, Daniele; Kırkım, Günay; Mungan, Serpil; Kolatan, Efsun; Aktaş, Safiye; Trabalzini, Franco; Ellidokuz, Hülya; Yılmaz, Osman; Mandala, Marco

    2017-04-01

    The aim of this study is to evaluate the effects of an intratympanic gentamicin-dexamethasone combination on the inner ear. Twenty-six Wistar albino rats were divided into four groups: Group I (Control), group II (Intratympanic dexamethasone; ITD), group III (Intratympanic gentamicin; ITG), and group IV (Intratympanic gentamicin and dexamethasone; ITGD). On the first day after basal auditory brainstem response (ABR) measurements, the ITG group received 0.03 mL of intratympanic gentamicin (26.7 mg/mL). Intratympanic injection of 0.06 mL of a solution containing 13.35 mg/mL gentamicin and 2 mg/mL dexamethasone was performed in the ITGD group. 0.03 mL of physiological intratympanic serum and dexamethasone (4 mg/mL) was applied in control and ITD groups, respectively. On the 7th day, ABR measurements were repeated and vestibular functions were evaluated. On the 21th day, ABR and vestibular tests were repeated, and the animals were sacrificed for histopathological investigation. The ITG group's hearing thresholds deteriorated in all frequencies. The ITGD group's hearing thresholds were significantly better than the ITG group, except at 8 kHz on the 7th day and in all frequencies at the 21th day measurements. The vestibular function scores of the ITG and ITGD groups were higher than the controls. Apoptotic changes were seen in cochlea, spiral ganglion, and vestibule of the ITG group. Cochlear and vestibular structures were well preserved in the ITGD group, similar to the controls. The ITGD combination led to a significant hearing preservation. Although in subjective vestibular tests, it seemed that vestibulotoxicity was present in both ITG and ITGD groups the histopathological investigations revealed no signs of vestibulotoxicity in the ITGD group in contrast to the ITG group. Further studies using a combination of different concentrations of gentamicin and dexamethasone are needed.

  13. Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study.

    Science.gov (United States)

    Bittar, Roseli Saraiva Moreira; Sato, Eduardo Setsuo; Ribeiro, Douglas Jósimo Silva; Tsuji, Robinson Koji

    Cochlear implants are undeniably an effective method for the recovery of hearing function in patients with hearing loss. To describe the preoperative vestibular assessment protocol in subjects who will be submitted to cochlear implants. Our institutional protocol provides the vestibular diagnosis through six simple tests: Romberg and Fukuda tests, assessment for spontaneous nystagmus, Head Impulse Test, evaluation for Head Shaking Nystagmus and caloric test. 21 patients were evaluated with a mean age of 42.75±14.38 years. Only 28% of the sample had all normal test results. The presence of asymmetric vestibular information was documented through the caloric test in 32% of the sample and spontaneous nystagmus was an important clue for the diagnosis. Bilateral vestibular areflexia was present in four subjects, unilateral arreflexia in three and bilateral hyporeflexia in two. The Head Impulse Test was a significant indicator for the diagnosis of areflexia in the tested ear (p=0.0001). The sensitized Romberg test using a foam pad was able to diagnose severe vestibular function impairment (p=0.003). The six clinical tests were able to identify the presence or absence of vestibular function and function asymmetry between the ears of the same individual. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  14. Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study

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    Roseli Saraiva Moreira Bittar

    Full Text Available Abstract Introduction: Cochlear implants are undeniably an effective method for the recovery of hearing function in patients with hearing loss. Objective: To describe the preoperative vestibular assessment protocol in subjects who will be submitted to cochlear implants. Methods: Our institutional protocol provides the vestibular diagnosis through six simple tests: Romberg and Fukuda tests, assessment for spontaneous nystagmus, Head Impulse Test, evaluation for Head Shaking Nystagmus and caloric test. Results: 21 patients were evaluated with a mean age of 42.75 ± 14.38 years. Only 28% of the sample had all normal test results. The presence of asymmetric vestibular information was documented through the caloric test in 32% of the sample and spontaneous nystagmus was an important clue for the diagnosis. Bilateral vestibular areflexia was present in four subjects, unilateral arreflexia in three and bilateral hyporeflexia in two. The Head Impulse Test was a significant indicator for the diagnosis of areflexia in the tested ear (p = 0.0001. The sensitized Romberg test using a foam pad was able to diagnose severe vestibular function impairment (p = 0.003. Conclusion: The six clinical tests were able to identify the presence or absence of vestibular function and function asymmetry between the ears of the same individual.

  15. Comparison of the vascular innervation of the rat cochlea and vestibular system.

    Science.gov (United States)

    Lyon, M J; Payman, R N

    2000-03-01

    In order to gain a better understanding of the neuronal and local control of inner ear blood flow, the vascular innervation to the rat cochlea and vestibular system was examined. Specimens were removed in toto beginning at the basilar artery extending to the anterior inferior cerebellar artery, labyrinthine artery, common cochlear artery, modiolar artery and anterior vestibular artery. When possible the vessels were dissected in continuity through the cribrose area. The vestibular endorgans were also removed. Specimens were examined using immunohistochemical techniques for the presence of vasoactive intestinal peptide, neuronal nitric oxide synthase, neuropeptide-Y, substance P and calcitonin gene related peptide. Results show that the vasculature to the cochlea and vestibular portion of the inner ear receive similar types of nonadrenergic innervation, that within the vestibular endorgans, only CGRP and SP were found in the neuroepithelium or in association with vessels, and that within the vestibular system, the majority of the vascular innervation appears to stop at or near the cribrose area. In the cochlea however, it extends to include the radiating arterioles. These findings suggest that cochlear blood flow is under finer control and that neuronally induced changes in blood flow may have a more global effect in the vestibular periphery.

  16. Interactive 3-dimensional virtual reality rehabilitation for patients with chronic imbalance and vestibular dysfunction.

    Science.gov (United States)

    Yeh, Shih-Ching; Chen, Shuya; Wang, Pa-Chun; Su, Mu-Chun; Chang, Chia-Huang; Tsai, Po-Yi

    2014-01-01

    Chronic imbalance is common in patients with vestibular dysfunction. Vestibular rehabilitation is effective in improving upright balance control. Vestibular rehabilitation exercises, such as Cawthorne-Cooksey exercises, include simple repetitive movements and have limited feedback and adaptive training protocols. Interactive systems based on virtual reality (VR) technology may improve vestibular rehabilitation. The objective of this study was to examine the effectiveness of an interactive 3-dimensional VR system for vestibular rehabilitation. In 49 subjects with vestibular dysfunction, VR rehabilitation exercises were performed in 6 sessions. Before and after rehabilitation, subjects were evaluated for performance of the training exercises; the center of pressure was measured for 20 seconds and balance indices were determined. Five training scores (total 6) showed a significant improvement. For balance indices in condition of non-stimulation, all of them (total 5) showed a trend of improvement, in which there was a significant improvement in mean mediolateral. For balance indices in condition of post-stimulation, there was a significant improvement in statokinesigram and maximum mediolateral. The VR rehabilitation exercises were effective in improving upright balance control in patients with vestibular dysfunction.

  17. [Functional results of cryosurgical procedures in rhegmatogenous retinal detachment including macula region - our experience].

    Science.gov (United States)

    Chrapek, O; Sín, M; Jirková, B; Jarkovský, J; Rehák, J

    2013-10-01

    Aim of this study is to evaluate retrospectively functional results of cryosurgical treatment of uncomplicated, idiopathic rhegmatogenous retinal detachment including macula region in phakic patients operated on at the Department of Ophthalmology, Faculty Hospital, Palacký University, Olomouc, Czech Republic, E.U., during the period 2002 -2013, and to evaluate the significance of the macula detachment duration for the final visual acuity. In the study group were included 56 eyes of 56 patients operated in the years 2003 - 2012 at the Department of Ophthalmology, Faculty Hospital, Palacký University, Olomouc. All patients were phakic and in all of them, the retinal detachment including the macula region was diagnosed. The mean follow-up period of the patients was 8,75 months. The initial and final visual acuity testing were performed. Comparing the initial and final visual acuity we rated the level of the visual acuity change. The result was stated as improved, if the visual acuity improved by 1 or more lines on the ETDRS chart. The result was rated as stabilized, if the visual acuity remained the same or it changed by 1 line of the ETDRS chart only. The result was evaluated as worsened, if the visual acuity decreased by 1 or more lines of the ETDRS chart. In the followed-up group, the authors compared visual acuity levels in patients with the macula detachment duration 10 days and 11 days. For the statistical evaluation of achieved results, the Mann - Whitney U test was used. The visual acuity improved in 49 (87 %), did not changed in 5 (9 %) and worsened in 2 (4 %) patients. The patients with macula detachment duration 10 days achieved statistically significant better visual acuity than patients with macula detachment duration 11 days. Patients with macula detachment duration 10 days have better prognosis for functional result than patients with macula detachment duration 11 days.

  18. Reabilitação vestibular: utilidade clínica em pacientes com esclerose múltipla Vestibular rehabilitation: clinical benefits to patients with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Bianca Simone Zeigelboim

    2010-01-01

    , diagnosed for six years, who referred frequent dizziness of moderate intensity for three years, headaches, falls, deviation of gait to the right and fainting sensations (sic. In the vestibular exam, she presented bilateral peripheral vestibular deficiency syndrome. The second case was a 49-year-old female, diagnosed for two years, who referred deviation of gait to the right, difficulty and/or pain with neck movement, paraesthesia of the extremities and vocal alteration. In the vestibular exam, she presented peripheral vestibular deficiency syndrome to the right. Both cases had significant improvements regarding physical, functional and emotional aspects of the Dizziness Handicap Inventory after vestibular rehabilitation. The protocol used benefitted the subjects' quality of life and favored the process of vestibular compensation.

  19. Personality changes in patients with vestibular dysfunction

    OpenAIRE

    Paul eSmith; Cynthia eDarlington

    2013-01-01

    The vestibular system is a sensory system that has evolved to detect linear and angular acceleration of the head in all planes so that the brain is not predominantly reliant on visual information to determine self-motion. Since the vestibular system first evolved in invertebrate species in order to detect gravitational vertical, it is likely that the central nervous system has developed a special dependence upon vestibular input. In addition to the deficits in eye movement and postural reflex...

  20. Motor development after vestibular deprivation in rats.

    Science.gov (United States)

    Geisler, H C; Gramsbergen, A

    1998-07-01

    This review summarizes the postural development in the rat and the influences of vestibular deprivation from the 5th postnatal day on this development. Vestibular deprivation leads to a delay in motor development. Most probably this delay is caused by a delay in the development of postural control, which is characterized by a retarded EMG development in postural muscles. Our results indicate that the developing nervous system cannot compensate for a vestibular deficit during the early phase of ontogeny.

  1. Changing perspective: The role of vestibular signals

    OpenAIRE

    Deroualle, Diane; Borel, Liliane; Deveze, Arnaud; Lopez, Christophe

    2015-01-01

    Social interactions depend on mechanisms such as the ability to take another person's viewpoint, i.e. visuo-spatial perspective taking. However, little is known about the sensorimotor mechanisms underpinning perspective taking. Because vestibular signals play roles in mental rotation and spatial cognition tasks and because damage to the vestibular cortex can disturb egocentric perspective, vestibular signals stand as important candidates for the sensorimotor foundations of perspective taking....

  2. Vestibular perception is slow: a review.

    Science.gov (United States)

    Barnett-Cowan, Michael

    2013-01-01

    Multisensory stimuli originating from the same event can be perceived asynchronously due to differential physical and neural delays. The transduction of and physiological responses to vestibular stimulation are extremely fast, suggesting that other stimuli need to be presented prior to vestibular stimulation in order to be perceived as simultaneous. There is, however, a recent and growing body of evidence which indicates that the perceived onset of vestibular stimulation is slow compared to the other senses, such that vestibular stimuli need to be presented prior to other sensory stimuli in order to be perceived synchronously. From a review of this literature it is speculated that this perceived latency of vestibular stimulation may reflect the fact that vestibular stimulation is most often associated with sensory events that occur following head movement, that the vestibular system rarely works alone, that additional computations are required for processing vestibular information, and that the brain prioritizes physiological response to vestibular stimulation over perceptual awareness of stimulation onset. Empirical investigation of these theoretical predictions is encouraged in order to fully understand this surprising result, its implications, and to advance the field.

  3. Personality changes in patients with vestibular dysfunction.

    Science.gov (United States)

    Smith, Paul F; Darlington, Cynthia L

    2013-10-29

    The vestibular system is a sensory system that has evolved to detect linear and angular acceleration of the head in all planes so that the brain is not predominantly reliant on visual information to determine self-motion. Since the vestibular system first evolved in invertebrate species in order to detect gravitational vertical, it is likely that the central nervous system has developed a special dependence upon vestibular input. In addition to the deficits in eye movement and postural reflexes that occur following vestibular dysfunction, there is convincing evidence that vestibular loss also causes cognitive and emotional disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and neocortex play in the sense of spatial orientation. Beyond this, however, patients with vestibular disorders have been reported to experience other personality changes that suggest that vestibular sensation is implicated in the sense of self. These are depersonalization and derealization symptoms such as feeling "spaced out", "body feeling strange" and "not feeling in control of self". We propose in this review that these symptoms suggest that the vestibular system may make a unique contribution to the concept of self through information regarding self-motion and self-location that it transmits, albeit indirectly, to areas of the brain such as the temporo-parietal junction (TPJ).

  4. International Clinical Protocol on Vestibular Disorders (Dizziness).

    Science.gov (United States)

    Trinus, Kostiantyn; Claussen, Claus-Frenz

    2017-12-01

    26-28 May at 43 Congress of Neurootological and Equilibriometric Society (Budapest, Hungary) International Clinical Protocol on Vestibular Disorders (Dizziness) being discussed and accepted as Consensus Document. Cochrane reports estimates that dizziness has prevalence of 22.9% in the last 12 months and an incidence of 3.1%. Only 1.8% of adults consulted a physician in the last 12 months. Cochrane reviews suggest that the evidence base for dizziness evaluation is weak, thus necessitates the creation of evidence-based document. Protocol is based at the new concept of vestibular system, which involves the vestibular peripheral sensors, space orientation tetrad, vestibular presentations in the brain cortex and vestibular effectory projections in the brain. Labyrinth consists of sensors, for which six modalities are adequate: 1. acceleration, 2. gravitation, 3. low frequency whole-body vibration, 4. Infrasound, 5. magnetic impulse, 6. metabolic changes. Vestibular system from rhomboid fosse gets the inputs from visual, acoustic, somatosensory organs, integrating them and forming space perception and orientation. Interaction with space is realized through sensory, motor, vegetative and limbic projections. So, vestibular disturbances may manifest as paropsia, tinnitus, numbness. Vestibular evoked potentials (not VEMP) and craniocorpography have highest sensitivity (90% and more). As vestibular dysfunction has recurrent character patients need monitoring.

  5. The role of the vestibular assessment.

    Science.gov (United States)

    Phillips, J S; FitzGerald, J E; Bath, A P

    2009-11-01

    To evaluate the role of vestibular assessment in the management of the dizzy patient. A retrospective review of case notes and vestibular assessment reports of 100 consecutive patients referred for vestibular assessment. Sixty of the 100 patients had an abnormal vestibular assessment. Eleven patients had benign paroxysmal positional vertigo as the sole diagnosis, of whom nine had not had a Dix-Hallpike manoeuvre performed before referral. Of patients referred for vestibular rehabilitation, 76 per cent had an abnormal electrophysiological assessment. After vestibular assessment, 35 patients were discharged with no further follow-up appointments in the ENT department. All patients should have a Dix-Hallpike manoeuvre performed prior to referral for vestibular assessment. The majority of our patients undergoing vestibular rehabilitation had abnormal test results, although a significant number did not. Prior to referral, it is worth considering the implication of a 'normal' and 'abnormal' result for the management of the patient. Careful consideration should be given to the development of dedicated dizziness clinics run by practitioners with a specialist interest in balance disorders, in order to ensure appropriate requests for vestibular assessment.

  6. Personality Changes in Patients with Vestibular Dysfunction

    Directory of Open Access Journals (Sweden)

    Paul eSmith

    2013-10-01

    Full Text Available The vestibular system is a sensory system that has evolved to detect linear and angular acceleration of the head in all planes so that the brain is not predominantly reliant on visual information to determine self-motion. Since the vestibular system first evolved in invertebrate species in order to detect gravitational vertical, it is likely that the central nervous system has developed a special dependence upon vestibular input. In addition to the deficits in eye movement and postural reflexes that occur following vestibular dysfunction, there is convincing evidence that vestibular loss also causes cognitive and emotional disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in the sense of spatial orientation. Beyond this, however, patients with vestibular disorders have been reported to experience other personality changes that suggest that vestibular sensation is implicated in the sense of self. These are depersonalisation and derealisation symptoms such as feeling ‘spaced out’, ‘body feeling strange’ and ‘not feeling in control of self’. We suggest in this review that these symptoms suggest that the vestibular system may make a unique contribution to the concept of self through the information regarding self-motion and self-location that it transmits, albeit indirectly, to areas of the brain such as the temporo-parietal junction.

  7. Acrophobia and pathological height vertigo: indications for vestibular physical therapy?

    Science.gov (United States)

    Whitney, Susan L; Jacob, Rolf G; Sparto, Patrick J; Olshansky, Ellen F; Detweiler-Shostak, Gail; Brown, Emily L; Furman, Joseph M

    2005-05-01

    Acrophobia (fear of heights) may be related to a high degree of height vertigo caused by visual dependence in the maintenance of standing balance. The purpose of this case report is to describe the use of vestibular physical therapy intervention following behavioral therapy to reduce a patient's visual dependence and height vertigo. Mr N was a 37-year-old man with agoraphobia (fear of open spaces) that included symptoms of height phobia. Exposure to heights triggered symptoms of dizziness. Intervention. Mr N underwent 8 sessions of behavioral therapy that involved exposure to heights using a head-mounted virtual reality device. Subsequently, he underwent 8 weeks of physical therapy for an individualized vestibular physical therapy exercise program. After behavioral therapy, the patient demonstrated improvements on the behavioral avoidance test and the Illness Intrusiveness Rating Scale, but dizziness and body sway responses to moving visual scenes did not decrease. After physical therapy, his dizziness and sway responses decreased and his balance confidence increased. Symptoms of acrophobia and sway responses to full-field visual motion appeared to respond to vestibular physical therapy administered after completion of a course of behavioral therapy. Vestibular physical therapy may have a role in the management of height phobia related to excessive height vertigo.

  8. Multivariate Analyses of Balance Test Performance, Vestibular Thresholds, and Age

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    Faisal Karmali

    2017-11-01

    Full Text Available We previously published vestibular perceptual thresholds and performance in the Modified Romberg Test of Standing Balance in 105 healthy humans ranging from ages 18 to 80 (1. Self-motion thresholds in the dark included roll tilt about an earth-horizontal axis at 0.2 and 1 Hz, yaw rotation about an earth-vertical axis at 1 Hz, y-translation (interaural/lateral at 1 Hz, and z-translation (vertical at 1 Hz. In this study, we focus on multiple variable analyses not reported in the earlier study. Specifically, we investigate correlations (1 among the five thresholds measured and (2 between thresholds, age, and the chance of failing condition 4 of the balance test, which increases vestibular reliance by having subjects stand on foam with eyes closed. We found moderate correlations (0.30–0.51 between vestibular thresholds for different motions, both before and after using our published aging regression to remove age effects. We found that lower or higher thresholds across all threshold measures are an individual trait that account for about 60% of the variation in the population. This can be further distributed into two components with about 20% of the variation explained by aging and 40% of variation explained by a single principal component that includes similar contributions from all threshold measures. When only roll tilt 0.2 Hz thresholds and age were analyzed together, we found that the chance of failing condition 4 depends significantly on both (p = 0.006 and p = 0.013, respectively. An analysis incorporating more variables found that the chance of failing condition 4 depended significantly only on roll tilt 0.2 Hz thresholds (p = 0.046 and not age (p = 0.10, sex nor any of the other four threshold measures, suggesting that some of the age effect might be captured by the fact that vestibular thresholds increase with age. For example, at 60 years of age, the chance of failing is roughly 5% for the lowest roll tilt

  9. Multivariate Analyses of Balance Test Performance, Vestibular Thresholds, and Age.

    Science.gov (United States)

    Karmali, Faisal; Bermúdez Rey, María Carolina; Clark, Torin K; Wang, Wei; Merfeld, Daniel M

    2017-01-01

    We previously published vestibular perceptual thresholds and performance in the Modified Romberg Test of Standing Balance in 105 healthy humans ranging from ages 18 to 80 (1). Self-motion thresholds in the dark included roll tilt about an earth-horizontal axis at 0.2 and 1 Hz, yaw rotation about an earth-vertical axis at 1 Hz, y-translation (interaural/lateral) at 1 Hz, and z-translation (vertical) at 1 Hz. In this study, we focus on multiple variable analyses not reported in the earlier study. Specifically, we investigate correlations (1) among the five thresholds measured and (2) between thresholds, age, and the chance of failing condition 4 of the balance test, which increases vestibular reliance by having subjects stand on foam with eyes closed. We found moderate correlations (0.30-0.51) between vestibular thresholds for different motions, both before and after using our published aging regression to remove age effects. We found that lower or higher thresholds across all threshold measures are an individual trait that account for about 60% of the variation in the population. This can be further distributed into two components with about 20% of the variation explained by aging and 40% of variation explained by a single principal component that includes similar contributions from all threshold measures. When only roll tilt 0.2 Hz thresholds and age were analyzed together, we found that the chance of failing condition 4 depends significantly on both (p = 0.006 and p = 0.013, respectively). An analysis incorporating more variables found that the chance of failing condition 4 depended significantly only on roll tilt 0.2 Hz thresholds (p = 0.046) and not age (p = 0.10), sex nor any of the other four threshold measures, suggesting that some of the age effect might be captured by the fact that vestibular thresholds increase with age. For example, at 60 years of age, the chance of failing is roughly 5% for the lowest roll tilt thresholds in

  10. Vestibular control of entorhinal cortex activity in spatial navigation

    Directory of Open Access Journals (Sweden)

    Pierre-Yves eJacob

    2014-06-01

    Full Text Available Navigation in rodents depends on both self-motion (idiothetic and external (allothetic information. Idiothetic information has a predominant role when allothetic information is absent or irrelevant. The vestibular system is a major source of idiothetic information in mammals. By integrating the signals generated by angular and linear accelerations during exploration, a rat is able to generate and update a vector pointing to its starting place and to perform accurate return. This navigation strategy, called path integration, has been shown to involve a network of brain structures. Among these structures, the entorhinal cortex (EC may play a pivotal role as suggested by lesion and electrophysiological data. In particular, it has been recently discovered that some neurons in the medial EC display multiple firing fields producing a regular grid-like pattern across the environment. Such regular activity may arise from the integration of idiothetic information. This hypothesis would be strongly strengthened if it was shown that manipulation of vestibular information interferes with grid cell activity. In the present paper we review neuroanatomical and functional evidence indicating that the vestibular system influences the activity of the brain network involved in spatial navigation. We also provide new data on the effects of reversible inactivation of the peripheral vestibular system on the EC theta rhythm. The main result is that TTX administration abolishes velocity-controlled theta oscillations in the EC, indicating that vestibular information is necessary for EC activity. Since recent data demonstrate that disruption of theta rhythm in the medial EC induces a disorganization of grid cell firing, our findings indicate that the integration of idiothetic information in the EC is essential to form a spatial representation of the environment.

  11. Vestibular control of entorhinal cortex activity in spatial navigation.

    Science.gov (United States)

    Jacob, Pierre-Yves; Poucet, Bruno; Liberge, Martine; Save, Etienne; Sargolini, Francesca

    2014-01-01

    Navigation in rodents depends on both self-motion (idiothetic) and external (allothetic) information. Idiothetic information has a predominant role when allothetic information is absent or irrelevant. The vestibular system is a major source of idiothetic information in mammals. By integrating the signals generated by angular and linear accelerations during exploration, a rat is able to generate and update a vector pointing to its starting place and to perform accurate return. This navigation strategy, called path integration, has been shown to involve a network of brain structures. Among these structures, the entorhinal cortex (EC) may play a pivotal role as suggested by lesion and electrophysiological data. In particular, it has been recently discovered that some neurons in the medial EC display multiple firing fields producing a regular grid-like pattern across the environment. Such regular activity may arise from the integration of idiothetic information. This hypothesis would be strongly strengthened if it was shown that manipulation of vestibular information interferes with grid cell activity. In the present paper we review neuroanatomical and functional evidence indicating that the vestibular system influences the activity of the brain network involved in spatial navigation. We also provide new data on the effects of reversible inactivation of the peripheral vestibular system on the EC theta rhythm. The main result is that tetrodotoxin (TTX) administration abolishes velocity-controlled theta oscillations in the EC, indicating that vestibular information is necessary for EC activity. Since recent data demonstrate that disruption of theta rhythm in the medial EC induces a disorganization of grid cell firing, our findings indicate that the integration of idiothetic information in the EC is essential to form a spatial representation of the environment.

  12. [Pharmacotherapy of Vestibular Disorders, Nystagmus and Cerebellar Disorders].

    Science.gov (United States)

    Feil, K; Böttcher, N; Kremmyda, O; Muth, C; Teufel, J; Zwergal, A; Brandt, T; Strupp, M

    2018-01-01

    There are currently different groups of drugs for the pharmacotherapy of vertigo, nystagmus and cerebellar disorders: antiemetics; anti-inflammatories, antimenieres, and antimigraineous medications and antidepressants, anticonvulsants, aminopyridines as well as acetyl-DL-leucine. In acute unilateral vestibulopathy, corticosteroids improve the recovery of peripheral vestibular function, but currently there is not sufficient evidence for a general recommendation. There is insufficient evidence to support the view that 16 mg t. i. d. or 48 mg t. i. d. betahistine has an effect in Menière's disease. Therefore, higher dosages are recommended. In animal studies, it was shown that betahistine increases cochlear blood flow. In vestibular paroxysmia, oxcarbazepine was effective (one randomized controlled trial (RCT)). Aminopyridines are recommended for the treatment of downbeat nystagmus (two RCTs) and episodic ataxia type 2 (EA2, one RCT). There has been no RCT on the efficacy of beta-blockers or topiramate but one RCT on flunarizine in vestibular migraine. Based on clinical experience, a treatment analogous to that for migraine without aura can be recommended. Acetyl-DL-leucine improved cerebellar ataxia (two observational studies); it also accelerated central compensation in an animal model of acute unilateral lesion, but RCTs were negative. There are ongoing RCTs on treatment of vestibular paroxysmia with carbamazepine (VESPA), acute unilateral vestibulopathy with betahistine (BETAVEST), vestibular migraine with metoprolol (PROVEMIG), benign paroxysmal positional vertigo with vitamin D (VitD@BPPV), EA2 with 4-aminopyridine versus acetazolamide (EAT-2-TREAT), and cerebellar ataxias with acetyl-DL-leucine (ALCAT). Georg Thieme Verlag KG Stuttgart · New York.

  13. Ontogenetic development of vestibular reflexes in amphibians

    Directory of Open Access Journals (Sweden)

    Hans Straka

    2016-11-01

    Full Text Available Vestibulo-ocular reflexes ensure gaze stability during locomotion and passively induced head/body movements. In precocial vertebrates such as amphibians, vestibular reflexes are required very early at the onset of locomotor activity. While the formation of inner ears and the assembly of sensory-motor pathways is largely completed soon after hatching, angular and translational/tilt vestibulo-ocular reflexes (VOR display differential functional onsets and mature with different time courses. Otolith-derived eye movements appear immediately after hatching, whereas the appearance and progressive amelioration of semicircular canal-evoked eye movements is delayed and dependent on the acquisition of sufficiently large semicircular canal diameters. Moreover, semicircular canal functionality is also required to tune the initially omnidirectional otolith-derived VOR. The tuning is due to a reinforcement of those vestibulo-ocular connections that are co-activated by semicircular canal and otolith inputs during natural head/body motion. This suggests that molecular mechanisms initially guide the basic ontogenetic wiring, whereas semicircular canal-dependent activity is required to establish the spatio-temporal specificity of the reflex. While a robust VOR is activated during passive head/body movements, locomotor efference copies provide the major source for compensatory eye movements during tail- and limb-based swimming of larval and adult frogs. The integration of active/passive motion-related signals for gaze stabilization occurs in central vestibular neurons that are arranged as segmentally iterated functional groups along rhombomere 1-8. However, at variance with the topographic maps of most other sensory systems, the sensory-motor transformation of motion-related signals occurs in segmentally specific neuronal groups defined by the extraocular motor output targets.

  14. Overlap between irritable bowel syndrome and functional dyspepsia including subtype analyses.

    Science.gov (United States)

    Choi, Yoon Jin; Kim, Nayoung; Yoon, Hyuk; Shin, Cheol Min; Park, Young Soo; Kim, Jin-Wook; Kim, Yong Sung; Lee, Dong Ho; Jung, Hyun Chae

    2017-09-01

    Coexistent gastrointestinal symptom profiles and prevalence or associated factors for the overlap between each functional dyspepsia (FD) and irritable bowel syndrome (IBS) group remain unclear. Thus, the aim of the present study was to evaluate the clinicodemographic features of FD, IBS, and IBS-FD overlap and assess the risk factors thereof, including subtype and genetic polymorphisms for IBS-FD. Consecutive patients were enrolled from the outpatient Gastroenterology clinics of Bundang Seoul National University Hospitals in Korea. All gastrointestinal symptoms occurring at least once per week in the previous 3 months were recorded. Diagnostic criteria of functional gastrointestinal disorders were based on the Rome III criteria. Risk factors including genetic polymorphisms of 5-HTTLPR and ADRA2A 1291 G alleles and CCK-1R intron 779T>C were assessed using a multivariate logistic regression model. A total of 632 subjects (278 control subjects, 308 FD, 156 IBS, and 110 who met the criteria for both FD and IBS) were included in this study. Patients with IBS-FD overlap had more severe symptoms (such as bloating, nausea, vomiting, hard or lumpy stools, defecation straining, and a feeling of incomplete bowel movement) and higher depression scores compared with non-overlap patients. Single/divorced or widowed marital status, nausea, bloating, and a feeling of incomplete emptying after bowel movements were independent risk factors for IBS-FD overlap among IBS patients. In contrast, young age, depression, bloating, and postprandial distress syndrome were positively associated with IBS-FD overlap among FD patients. 5-HTTLPR L/L was a risk factor for the co-occurrence of IBS-C among FD patients (OR: 12.47; 95% CI: 2.00-77.75; P = 0.007). Bloating was a risk factor for IBS-FD overlap. Patients with postprandial distress syndrome have a higher risk of coexisting IBS, particularly constipation-dominant IBS. © 2017 Journal of Gastroenterology and Hepatology Foundation and

  15. Maternal susceptibility to nausea and vomiting of pregnancy: is the vestibular system involved?

    Science.gov (United States)

    Black, F. Owen

    2002-01-01

    Nausea and vomiting of pregnancy shares many characteristics with motion sickness, a vestibular dependent phenomenon. A number of physiologic changes that occur in normal pregnancy are also known to accompany nausea and vomiting in patients with motion sickness and certain vestibular disorders. This chapter summarizes some shared features of both phenomena. The unmasking of subclinical vestibular disorders may account for some cases of hyperemesis gravidarum. Hormonal effects on neurotransmitter function may also play a role in nausea and vomiting of pregnancy and in some vestibular disorders; however, the specific neural mechanisms of nausea and vomiting have not been identified. Until the neurochemical processes underlying these phenomena are understood, prevention and management will remain in the domain of astute, but so far limited, clinical observation.

  16. Adaptations of the vestibular system to short and long-term exposures to altered gravity

    Science.gov (United States)

    Bruce, L.

    Long-term space flight creates unique environmental conditions to which the vestibular system must adapt for optimal survival. We are studying two aspects of this vestibular adaptation: (1) How does long-term exposure to microgravity and hypergravity affect the development of vestibular afferents? (2) How does short- term exposure to extremely rapid changes in gravity, such as those that occur during launch and landing, affect the vestibular system. During space flight the gravistatic receptors in the otolith organs are effectively unloaded. In hypergravity conditions they are overloaded. However, the angular acceleration receptors of the semicircular canals receive relatively normal stimulation in both micro- and hypergravity.Rat embryos exposed to microgravity from gestation day 10 (prior to vestibular function) until gestation day 20 (vestibular system is somewhat functional) showed that afferents from the posterior vertical canal projecting to the medial vestibular nucleus developed similarly in microgravity, hypergravity, and in controls . However, afferents from the saccule showed delayed development in microgravity as compared to development in hypergravity and in controls. Cerebellar plasticity is crucial for modification of sensory-motor control and learning. Thus we explored the possibility that strong vestibular stimuli would modify cerebellar motor control (i.e., eye movement, postural control, gut motility) by altering the morphology of cerebellar Purkinje cells. To study the effects of short-term exposures to strong vestibular stimuli we focused on structural changes in the vestibulo-cerebellum that are caused by strong vestibular stimuli. Adult mice were exposed to various combinations of constant and/or rapidly changing angular and linear accelerations for 8.5 min (the time length of shuttle launch). Our data shows that these stimuli cause intense excitation of cerebellar Purkinje cells, inducing up-regulation of clathrin-mediated endocytosis

  17. Physical therapy management of peripheral vestibular dysfunction: two clinical case reports.

    Science.gov (United States)

    Gill-Body, K M; Krebs, D E; Parker, S W; Riley, P O

    1994-02-01

    We describe the treatment of two patients with peripheral vestibular dysfunction using a novel, staged exercise program. Response to treatment was documented. The first patient, a 62-year-old woman with unilateral vestibular dysfunction (UVD) and a 6-month history of disequilibrium following herpes zoster oticus resulting in damage to the right inner ear, was treated with an 8-week course of vestibular physical therapy. During the 8 weeks, the patient attended weekly physical therapy sessions and was trained to perform vestibular adaptation exercises on a daily basis at home. The second patient, a 53-year-old woman with progressive disequilibrium secondary to profound bilateral vestibular hypofunction (BVH), was treated with a 16-week course of vestibular physical therapy. During the first 8 weeks, the patient attended weekly physical therapy sessions and was trained to perform vestibular adaptation and substitution exercises on a daily basis at home. During the second 8 weeks, the patient continued performing vestibular physical therapy exercises at home independently. Vestibular function (sinusoidal vertical axis rotation testing), postural control (clinical tests and posturography), stability during the performance of selected activities of daily living (ADLs), and self-perception of symptoms and handicap were measured prior to and at the conclusion of treatment for both patients and at the midpoint of treatment for the patient with BVH. After 8 weeks of treatment, both patients reported improvements in self-perception of symptoms and handicap and demonstrated objective improvements in clinical balance tests, posturography, and several kinematic indicators of stability during the performance of selected ADLs. Further improvements were noted in the patient with BVH after 16 weeks of treatment. Improvements in postural control were noted after 8 weeks of treatment for the patient with UVD and after 16 weeks for the patient with BVH. Vestibular function improved

  18. Prevalence and impact of bilateral vestibular hypofunction: results from the 2008 US National Health Interview Survey.

    Science.gov (United States)

    Ward, Bryan K; Agrawal, Yuri; Hoffman, Howard J; Carey, John P; Della Santina, Charles C

    2013-08-01

    Profound bilateral vestibular hypofunction (BVH) causes disabling oscillopsia, chronic disequilibrium, and postural instability, but little is known about its epidemiology and impact. To assess prevalence and functional impact of BVH in the US adult population. National cross-sectional survey using a national database and corollary validation study. Adult respondents to the 2008 Balance and Dizziness Supplement to the US National Health Interview Survey (N = 21 782). Prevalence of BVH, socioeconomic and quality-of-life impact of BVH, and fall risk. Criteria for the survey-based diagnosis of BVH included all of the following: presence of visual blurring with head movement; unsteadiness; difficulty walking in darkness or unsteady surfaces and in a straight path; and symptoms being at least "a big problem" and present for at least 1 year, in the absence of other neurologic conditions or eye pathologic conditions affecting vision. Adjusted national estimates from this survey indicate the prevalence of BVH in 2008 was 28 per 100 000 US adults (64 046 Americans). Of the participants with BVH, 44% reported changing their driving habits because of their symptoms, 56% reported reduced participation in social activities, and 58% reported difficulties with activities of daily living. Respondents with BVH had a 31-fold increase in the odds of falling in multivariate analyses compared with all respondents, with 25% reporting a recent fall-related injury. As estimated by the presence of specific symptoms in a nationally representative survey, BVH has considerable socioeconomic and quality-of-life impacts and significantly increases fall risk. These data support the need for new therapeutic strategies for BVH, including vestibular rehabilitation and implantable vestibular prostheses.

  19. Outcomes Following a Vestibular Rehabilitation and Aerobic Training Program to Address Persistent Post-Concussion Symptoms.

    Science.gov (United States)

    Moore, Brian M; Adams, Joseph T; Barakatt, Edward

    2016-01-01

    To describe changes in adults with persistent symptoms and disability following a concussion after completing a supervised home exercise vestibular rehabilitation (VR) program combined with aerobic training. Participants included 14 consecutive individuals referred for VR within the context of a comprehensive concussion center. Outcome measures were administered at initial evaluation, 3 mos, and 6 mos. Outcome measures included: Rivermead Post-Concussion Questionnaire symptom (RPQ-3) and function (RPQ-13) subcategories, Dizziness Handicap Inventory (DHI), Activities-specific Balance Confidence Scale (ABC), functional gait assessment (FGA), return to work/study (RTW), and return to activity (RTA). At 6 months, all clinical outcome measures were found to be statistically significant or approaching statistical significance: RPQ-3 (pVR program with aerobic training, significant improvements were observed in participants' report of concussion-related symptoms, function, and return to meaningful activities.

  20. Changing perspective: The role of vestibular signals.

    Science.gov (United States)

    Deroualle, Diane; Borel, Liliane; Devèze, Arnaud; Lopez, Christophe

    2015-12-01

    Social interactions depend on mechanisms such as the ability to take another person's viewpoint, i.e. visuo-spatial perspective taking. However, little is known about the sensorimotor mechanisms underpinning perspective taking. Because vestibular signals play roles in mental rotation and spatial cognition tasks and because damage to the vestibular cortex can disturb egocentric perspective, vestibular signals stand as important candidates for the sensorimotor foundations of perspective taking. Yet, no study merged natural full-body vestibular stimulations and explicit visuo-spatial perspective taking tasks in virtual environments. In Experiment 1, we combined natural vestibular stimulation on a rotatory chair with virtual reality to test how vestibular signals are processed to simulate the viewpoint of a distant avatar. While they were rotated, participants tossed a ball to a virtual character from the viewpoint of a distant avatar. Our results showed that vestibular signals influence perspective taking in a direction-specific way: participants were faster when their physical body rotated in the same direction as the mental rotation needed to take the avatar's viewpoint. In Experiment 2, participants realized 3D object mental rotations, which did not involve perspective taking, during the same whole-body vestibular stimulation. Our results demonstrated that vestibular stimulation did not affect 3D object mental rotations. Altogether, these data indicate that vestibular signals have a direction-specific influence on visuo-spatial perspective taking (self-centered mental imagery), but not a general effect on mental imagery. Findings from this study suggest that vestibular signals contribute to one of the most crucial mechanisms of social cognition: understanding others' actions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Vestibular ataxia and its measurement in man

    Science.gov (United States)

    Fregly, A. R.

    1974-01-01

    Methods involved in and results obtained with a new comprehensive ataxia test battery are described, and definitions of spontaneous and induced vestibular ataxia in man are given in terms of these findings. In addition, the topic of alcohol-induced ataxia in relation to labyrinth function is investigated. Items in the test battery comprise a sharpened Romberg test, in which the subject stands on the floor with eyes closed and arms folded against his chest, feet heel-to-toe, for 60 seconds; an eyes-open walking test; an eyes-open standing test; an eyes-closed standing test; an eyes-closed on-leg standing test; an eyes-closed walk a line test; an eyes-closed heel-to-toe walking test; and supplementary ataxia tests such as the classical Romberg test.

  2. [Vestibular influences on human locomotion: results obtained using galvanic vestibular stimulation].

    Science.gov (United States)

    Stolbkov, Iu K; Gerasimenko, Iu P

    2014-06-01

    Locomotion is the most important mode of our movement in space. The role of the vestibular system during human locomotion is not well studied, mainly due to problems associated with its isolation stimulation. It is difficult to stimulate this system in isolation during locomotion because the real movement of the head to activate the vestibular end-organs inevitably leads to the activation of other sensory inputs. Galvanic stimulation is not a natural way to stimulate the vestibular system, but it has the advantage providing an isolated stimulation of the vestibular inputs. This technique is relatively novel in the examination of vestibular contributions during human locomotion. In our review we consider the current data regarding the effect of vestibular signals on human locomotion by using galvanic vestibular stimulation.

  3. How Vestibular Neurons Solve the Tilt/Translation Ambiguity: Comparison of Brainstem, Cerebellum, and Thalamus

    OpenAIRE

    Dora E. Angelaki; Yakusheva, Tatyana A.

    2009-01-01

    The peripheral vestibular system is faced by a sensory ambiguity, where primary otolith afferents respond identically to translational (inertial) accelerations and changes in head orientation relative to gravity. Under certain conditions, this sensory ambiguity can be resolved using extra-otolith cues, including semicircular canal signals. Here we review and summarize how neurons in the vestibular nuclei, rostral fastigial nuclei, cerebellar nodulus/uvula, and thalamus respond during combinat...

  4. Manual therapy with and without vestibular rehabilitation for cervicogenic dizziness: a systematic review

    Directory of Open Access Journals (Sweden)

    Lystad Reidar P

    2011-09-01

    Full Text Available Abstract Background Manual therapy is an intervention commonly advocated in the management of dizziness of a suspected cervical origin. Vestibular rehabilitation exercises have been shown to be effective in the treatment of unilateral peripheral vestibular disorders, and have also been suggested in the literature as an adjunct in the treatment of cervicogenic dizziness. The purpose of this systematic review is to evaluate the evidence for manual therapy, in conjunction with or without vestibular rehabilitation, in the management of cervicogenic dizziness. Methods A comprehensive search was conducted in the databases Scopus, Mantis, CINHAL and the Cochrane Library for terms related to manual therapy, vestibular rehabilitation and cervicogenic dizziness. Included studies were assessed using the Maastricht-Amsterdam criteria. Results A total of fifteen articles reporting findings from thirteen unique investigations, including five randomised controlled trials and eight prospective, non-controlled cohort studies were included in this review. The methodological quality of the included studies was generally poor to moderate. All but one study reported improvement in dizziness following either unimodal or multimodal manual therapy interventions. Some studies reported improvements in postural stability, joint positioning, range of motion, muscle tenderness, neck pain and vertebrobasilar artery blood flow velocity. Discussion Although it has been argued that manual therapy combined with vestibular rehabilitation may be superior in the treatment of cervicogenic dizziness, there are currently no observational and experimental studies demonstrating such effects. A rationale for combining manual therapy and vestibular rehabilitation in the management of cervicogenic dizziness is presented. Conclusion There is moderate evidence to support the use of manual therapy, in particular spinal mobilisation and manipulation, for cervicogenic dizziness. The evidence

  5. Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input.

    Science.gov (United States)

    Sprenger, Andreas; Wojak, Jann F; Jandl, Nico M; Helmchen, Christoph

    2017-01-01

    Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive

  6. Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

    Science.gov (United States)

    Sprenger, Andreas; Wojak, Jann F.; Jandl, Nico M.; Helmchen, Christoph

    2017-01-01

    Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive

  7. The frog vestibular system as a model for lesion-induced plasticity: basic neural principles and implications for posture control

    Directory of Open Access Journals (Sweden)

    Francois M Lambert

    2012-04-01

    Full Text Available Studies of behavioral consequences after unilateral labyrinthectomy have a long tradition in the quest of determining rules and limitations of the CNS to exert plastic changes that assist the recuperation from the loss of sensory inputs. Frogs were among the first animal models to illustrate general principles of regenerative capacity and reorganizational neural flexibility after a vestibular lesion. The continuous successful use of the latter animals is in part based on the easy access and identifiability of nerve branches to inner ear organs for surgical intervention, the possibility to employ whole brain preparations for in vitro studies and the limited degree of freedom of postural reflexes for quantification of behavioral impairments and subsequent improvements. Major discoveries that increased the knowledge of post-lesional reactive mechanisms in the central nervous system include alterations in vestibular commissural signal processing and activation of cooperative changes in excitatory and inhibitory inputs to disfacilitated neurons. Moreover, the observed increase of synaptic efficacy in propriospinal circuits illustrates the importance of limb proprioceptive inputs for postural recovery. Accumulated evidence suggests that the lesion-induced neural plasticity is not a goal-directed process that aims towards a meaningful restoration of vestibular reflexes but rather attempts a survival of those neurons that have lost their excitatory inputs. Accordingly, the reaction mechanism causes an improvement of some components but also a deterioration of other aspects as seen by spatio-temporally inappropriate vestibulo-motor responses, similar to the consequences of plasticity processes in various sensory systems and species. The generality of the findings indicate that frogs continue to form a highly amenable vertebrate model system for exploring molecular and physiological events during cellular and network reorganization after a loss of

  8. Multirate Simulations of String Vibrations Including Nonlinear Fret-String Interactions Using the Functional Transformation Method

    Directory of Open Access Journals (Sweden)

    R. Rabenstein

    2004-06-01

    Full Text Available The functional transformation method (FTM is a well-established mathematical method for accurate simulations of multidimensional physical systems from various fields of science, including optics, heat and mass transfer, electrical engineering, and acoustics. This paper applies the FTM to real-time simulations of transversal vibrating strings. First, a physical model of a transversal vibrating lossy and dispersive string is derived. Afterwards, this model is solved with the FTM for two cases: the ideally linearly vibrating string and the string interacting nonlinearly with the frets. It is shown that accurate and stable simulations can be achieved with the discretization of the continuous solution at audio rate. Both simulations can also be performed with a multirate approach with only minor degradations of the simulation accuracy but with preservation of stability. This saves almost 80% of the computational cost for the simulation of a six-string guitar and therefore it is in the range of the computational cost for digital waveguide simulations.

  9. Motor development after vestibular deprivation in rats

    NARCIS (Netherlands)

    Geisler, HC; Gramsbergen, A

    This review summarizes the postural development in the rat and the influences of vestibular deprivation from the 5th postnatal day on this development. Vestibular deprivation leads to a delay in motor development. Most probably this delay is caused by a delay in the development of postural control,

  10. Pulmonary Function After Treatment for Embryonal Brain Tumors on SJMB03 That Included Craniospinal Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Green, Daniel M., E-mail: daniel.green@stjude.org [Department of Epidemiology and Cancer Control, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Billups, Catherine A. [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Stokes, Dennis C. [Department of Pediatrics, University of Tennessee School of Medicine, Memphis, Tennessee (United States); Broniscer, Alberto [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Bartels, Ute [Department of Haematology and Oncology, The Hospital for Sick Children, Toronto, Ontario (Canada); Chintagumpala, Murali [Department of Pediatric Medicine, Texas Children' s Cancer and Hematology Centers, Baylor College of Medicine, Houston, Texas (United States); Hassall, Timothy E. [Department of Haematology and Oncology, Royal Children' s Hospital, Brisbane (Australia); Gururangan, Sridharan [Department of Pediatrics, Duke University Medical Center, Durham, North Carolina (United States); McCowage, Geoffrey B. [Department of Pediatrics, Children' s Hospital at Westmead, Sydney (Australia); Heath, John A. [Children' s Cancer Center, Royal Children' s Hospital Melbourne, Melbourne (Australia); Cohn, Richard J. [Department of Clinical Oncology, Sydney Children' s Hospital, Sydney (Australia); Fisher, Michael J. [Department of Pediatrics, Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States); Srinivasan, Ashok [Department of Bone Marrow Transplantation & Cellular Therapy, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Robinson, Giles W.; Gajjar, Amar [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2015-09-01

    Purpose: The treatment of children with embryonal brain tumors (EBT) includes craniospinal irradiation (CSI). There are limited data regarding the effect of CSI on pulmonary function. Methods: Protocol SJMB03 enrolled patients 3 to 21 years of age with EBT. Pulmonary function tests (PFTs) (forced expiratory volume in 1 second [FEV{sub 1}] and forced vital capacity [FVC] by spirometry, total lung capacity [TLC] by nitrogen washout or plethysmography, and diffusing capacity of the lung for carbon monoxide corrected for hemoglobin [DLCO{sub corr}]) were obtained. Differences between PFTs obtained immediately after the completion of CSI and 24 or 60 months after the completion of treatment (ACT) were compared using exact Wilcoxon signed-rank tests and repeated-measures models. Results: Between June 24, 2003, and March 1, 2010, 303 eligible patients (spine dose: ≤2345 cGy, 201; >2345 cGy, 102; proton beam, 20) were enrolled, 260 of whom had at least 1 PFT. The median age at diagnosis was 8.9 years (range, 3.1-20.4 years). The median thoracic spinal radiation dose was 23.4 Gy (interquartile range [IQR], 23.4-36.0 Gy). The median cyclophosphamide dose was 16.0 g/m{sup 2} (IQR, 15.7-16.0 g/m{sup 2}). At 24 and 60 months ACT, DLCO{sub corr} was <75% predicted in 23% (27/118) and 25% (21/84) of patients, FEV{sub 1} was <80% predicted in 20% (34/170) and 29% (32/109) of patients, FVC was <80% predicted in 27% (46/172) and 28% (30/108) of patients, and TLC was <75% predicted in 9% (13/138) and 11% (10/92) of patients. DLCO{sub corr} was significantly decreased 24 months ACT (median difference [MD] in % predicted, 3.00%; P=.028) and 60 months ACT (MD in % predicted, 6.00%; P=.033) compared with the end of radiation therapy. These significant decreases in DLCO{sub corr} were also observed in repeated-measures models (P=.011 and P=.032 at 24 and 60 months ACT, respectively). Conclusions: A significant minority of EBT survivors experience PFT deficits after CSI

  11. Magnetic Vestibular Stimulation in Subjects with Unilateral Labyrinthine Disorders

    Directory of Open Access Journals (Sweden)

    Bryan Kevin Ward

    2014-03-01

    Full Text Available We recently discovered that static magnetic fields from high-strength MRI machines induce nystagmus in all normal humans, and that a magnetohydrodynamic (MHD Lorentz force, derived from ionic currents in the endolymph and pushing on the cupula, best explains this effect. Individuals with no labyrinthine function have no nystagmus. The influence of magnetic vestibular stimulation (MVS in individuals with unilateral loss of labyrinthine function is unknown and may provide insight into mechanism of MVS. These individuals should experience MVS, but with differences consistent with their residual labyrinthine function. We recorded eye movements in the static magnetic field of a 7T MRI machine in nine individuals with unilateral labyrinthine hypofunction, as determined by head impulse testing and vestibular-evoked myogenic potentials (VEMP. Eye movements were recorded using infrared videooculography. Static head positions were varied in pitch with the body supine, and slow-phase eye velocity (SPV was assessed. All subjects exhibited predominantly horizontal nystagmus after entering the magnet head-first, lying supine. The SPV direction reversed when entering feet-first. Pitching chin-to-chest caused subjects to reach a null point for horizontal SPV. Right unilateral vestibular hypofunction (UVH subjects developed slow-phase-up nystagmus and left UVH subjects, slow-phase-down nystagmus. Vertical and torsional components were consistent with superior semicircular canal excitation or inhibition, respectively, of the intact ear. These findings provide compelling support for the hypothesis that MVS is a result of a Lorentz force and suggest that the function of individual structures within the labyrinth can be assessed with MVS. As a novel method of comfortable and sustained labyrinthine stimulation, MVS can provide new insights into vestibular physiology and pathophysiology.

  12. Clinical course of vestibular schwannoma in pediatric neurofibromatosis Type 2.

    Science.gov (United States)

    Choi, Jung Won; Lee, Ji Yeoun; Phi, Ji Hoon; Wang, Kyu-Chang; Chung, Hyun-Tai; Paek, Sun Ha; Kim, Dong Gyu; Park, Sung-Hye; Kim, Seung-Ki

    2014-06-01

    Neurofibromatosis Type 2 (NF2) is an autosomal-dominant inherited disease, characterized by multiple neoplasia syndromes, including meningioma, schwannoma, glioma, and ependymoma. In this report, the authors present their clinical experience with pediatric NF2 patients. In particular, they focused on the clinical course of vestibular schwannoma (VS), including the natural growth rate, tumor control, and functional hearing outcomes. From May 1988 to June 2012, the authors recruited patients who were younger than 18 years and fulfilled the Manchester criteria. In total, 25 patients were enrolled in this study. The authors analyzed the clinical course of these patients. In addition, they measured the natural growth rate of VS before any treatment in these children with NF2. Then, they evaluated the tumor control rate and functional hearing outcomes after the treatment of VS. The mean age at the onset of NF2-related symptoms was 9.9 ± 4.5 years (mean ± SD, range 1-17 years). The mean age at the diagnosis of NF2 was 12.9 ± 2.9 years (range 5-17 years). The mean follow-up period was 89.3 months (range 12-311 months). As initial manifestations, nonvestibular symptoms were frequently observed in pediatric patients with NF2. The mean natural growth rate of VS was 0.33 ± 0.41 cm(3)/year (range 0-1.35 cm(3)/year). The tumor control rate of VS was 35.3% at 3 years after Gamma Knife surgery (GKS). The actuarial rate of useful hearing preservation was 67% in the 1st year and 53% in the 5th year after GKS. Clinical manifestations in children with NF2 were highly variable, compared with their adult counterparts. The natural growth rate of VS in children is slow, and this oncological feature may explain the diverse clinical manifestations besides vestibular symptoms in children with NF2. The treatment outcome of GKS for VS in children with NF2 was not favorable compared with previous reports of affected adults.

  13. Posture, head stability, and orientation recovery during vestibular regeneration in pigeons.

    Science.gov (United States)

    Dickman, J David; Lim, Insook

    2004-09-01

    Compensatory behavior such as oculomotor, gaze, and postural responses that occur during movement largely depend upon a functioning vestibular system. In the present study, the initial loss and subsequent recovery of postural and head stability in pigeons undergoing vestibular regeneration were examined. Adult pigeons were trained to manipulate a straight run chamber to peck an illuminated key for fluid reward. Six behavioral measures assessing performance, posture, and head stability were quantified. These included run latency, steps (walking), path negotiation (lane changes), gaze saccades, head bobs, and head shakes. Once normative values were obtained for four birds, complete lesion of all receptor cells and denervation of the epithelia in the vestibular endorgans were produced using a single intralabyrinthine application of streptomycin sulfate. Each bird was then tested at specific times during regeneration and the same behavioral measures examined. At 7 days post-streptomycin treatment (PST), all birds exhibited severe postural and head instability, with tremors, head shakes, staggering, and circling predominating. No normal trial runs, walking, gaze saccades, or head bobs were present. Many of these dysfunctions persisted through 3-4 weeks PST. Gradually, tremor and head shakes diminished and were replaced with an increasing number of normal head bobs during steps and gaze saccades. Beginning at 4 weeks PST, but largely inaccurate, was the observed initiation of directed steps, less staggering, and some successful path negotiation. As regeneration progressed, spatial orientation and navigation ability increased and, by 49 days PST, most trials were successful. By 70 days PST, all birds had recovered to pretreatment levels. Thus, it was observed that ataxia must subside, coincident with normalized head and postural stability prior to the recovery of spatial orientation and path navigation recovery. Parallels in recovery were drawn to hair cell regeneration

  14. Development of a Statistical Model for the Prediction of Common Vestibular Diagnoses.

    Science.gov (United States)

    Friedland, David R; Tarima, Sergey; Erbe, Christy; Miles, Alexia

    2016-04-01

    Treatment of patients with vestibular disorders can be complex, requires lengthy clinic visit time, and uses greater clinical resources for diagnosis. A pre-encounter intake questionnaire may predict the most common disorders, allowing for more efficient allocation of resources and use of clinicians. To develop a statistical model for predicting vestibular diagnoses, prior to clinical evaluation, from an intake questionnaire. Retrospective review of 414 consecutive new vestibular patient intake questionnaires (September 2012 through January 2014) and associated medical records with performance of logistic regression analyses and development of predictive models (July 2013 through May 2015). Use of a vestibular intake questionnaire for triaging of new patients with complaints of dizziness. Predictors for the diagnosis of benign paroxysmal positional vertigo (BPPV), Ménière's disease, and vestibular migraine. Of the 414 questionnaires analyzed, 381 (92%) had clinician information necessary to define a final diagnosis. Patients were 34% male and had a mean (range) age of 57 (19-91) years. Of the diagnoses, 183 (48%) were ear related (including 103 BPPV and 49 Meniere's disease), 141 (37%) neurological (including 109 vestibular migraine), 36 (9%) medical, 8 (2%) of psychological origin, 46 (12%) of unknown etiology, and 33 (9%) other causes. The diagnosis of BPPV could be predicted from 4 variables with a sensitivity of 79% and specificity of 65%. The diagnosis of Ménière's disease could be predicted from 5 variables with a sensitivity of 81% and specificity of 85%. The diagnosis of vestibular migraine could be predicted from 4 variables with a sensitivity of 76% and specificity of 59%. A pre-encounter history questionnaire can provide useful diagnostic information for common vestibular disorders. This can help direct appointment scheduling to improve clinical efficiency, time to intervention, and use of resources. Further refinement may enable the use of shorter

  15. Vestibular end organ injury induced by middle ear treatment with ferric chloride in rats.

    Science.gov (United States)

    Lee, J H; Kim, M S; Park, B R

    2017-02-01

    Sensorineural hearing loss, ataxia, pyramidal signs, and vestibular deficits characterize superficial siderosis of the central nervous system. This study investigated changes in vestibular function, free radical formation, and phosphorylated cJun expression in the vestibular end organs after middle ear treatment with a ferric chloride (FeCl3) solution. A single injection of 70% FeCl3 solution into the unilateral middle ear cavity caused static vestibular symptoms, such as spontaneous nystagmus and head tilt. Asymmetric expression of c-Fos protein was observed in the bilateral vestibular nuclei and prepositus hypoglossal nuclei within 6 h after injection. Histopathologic examinations revealed partial hair cell loss, degeneration of the supporting stroma, and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells in the neuroepithelial layer of the crista ampullaris in FeCl3-treated animals. 5-(And-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester and diaminofluorescein-2 diacetate fluorescence and immunoreactivity for nitrotyrosine increased markedly in the sensory neuroepithelial layer and nerve bundles of the crista ampullaris after 2 h. Strong immunoreactivity for phospho-cJun and cJun was observed in the type I hair cells of the crista ampullaris 120 h after injection. Thus, a single short-term treatment with a high concentration of FeCl3 in the unilateral middle ear cavity can induce activation of intracellular signals for cJun protein and oxidative stress through the formation of reactive oxygen species and nitric oxide in vestibular sensory receptors, resulting in vestibular dysfunction. These results suggest that activation of intracellular signals for cJun protein and oxidative stress may be a key component of the pathogenesis of vestibular deficits in patients with superficial siderosis.

  16. Convergence of Vestibular and Neck Proprioceptive Sensory Signals in the Cerebellar Interpositus

    Science.gov (United States)

    Luan, Hongge; Gdowski, Martha Johnson; Newlands, Shawn D.; Gdowski, Greg T.

    2013-01-01

    The cerebellar interpositus nucleus (IN) contributes to controlling voluntary limb movements. We hypothesized that the vestibular signals within the IN might be transformed into coordinates describing the body’s movement, appropriate for controlling limb movement. We tested this hypothesis by recording from IN neurons in alert squirrel monkeys during vestibular and proprioceptive stimulation produced during (1) yaw head-on-trunk rotation about the C1–C2 axis while in an orthograde posture and (2) lateral side-to-side flexion about the C6 –T3 axis while in a pronograde posture. Neurons (44/67) were sensitive to vestibular stimulation (23/44 to rotation and translation, 14/44 to rotation only, 7/44 to translation only). Most neurons responded during contralateral movement. Neurons (29/44) had proprioceptive responses; the majority (21/29) were activated during neck rotation and lateral flexion. In all 29 neurons with convergent vestibular and neck proprioceptive input those inputs functionally canceled each other during all combined sensory stimulation, whether in the orthograde or pronograde posture. These results suggest that two distinct populations of IN neurons exist, each of which has vestibular sensitivity. One population carries vestibular signals that describe the head’s movement in space as is traditional for vestibular signals without proprioceptive signals. A second population of neurons demonstrated precise matching of vestibular and proprioceptive signals, even for complicated stimuli, which activated the semicircular canals and otolith organs and involved both rotation and flexion in the spine. Such neurons code body (not head) motion in space, which may be the appropriate platform for controlling limb movements. PMID:23325256

  17. Distribution of high-conductance calcium-activated potassium channels in rat vestibular epithelia.

    Science.gov (United States)

    Schweizer, Felix E; Savin, David; Luu, Cindy; Sultemeier, David R; Hoffman, Larry F

    2009-11-10

    Voltage- and calcium-activated potassium channels (BK) are important regulators of neuronal excitability. BK channels seem to be crucial for frequency tuning in nonmammalian vestibular and auditory hair cells. However, there are a paucity of data concerning BK expression in mammalian vestibular hair cells. We therefore investigated the localization of BK channels in mammalian vestibular hair cells, specifically in rat vestibular neuroepithelia. We find that only a subset of hair cells in the utricle and the crista ampullaris express BK channels. BK-positive hair cells are located mainly in the medial striolar region of the utricle, where they constitute at most 12% of hair cells, and in the central zone of the horizontal crista. A majority of BK-positive hair cells are encapsulated by a calretinin-positive calyx defining them as type I cells. The remainder are either type I cells encapsulated by a calretinin-negative calyx or type II hair cells. Surprisingly, the number of BK-positive hair cells in the utricle peaks in juvenile rats and declines in early adulthood. BK channels were not found in vestibular afferent dendrites or somata. Our data indicate that BK channel expression in the mammalian vestibular system differs from the expression pattern in the mammalian auditory and the nonmammalian vestibular system. The molecular diversity of vestibular hair cells indicates a functional diversity that has not yet been fully characterized. The predominance of BK-positive hair cells within the medial striola of juvenile animals suggests that they contribute to a scheme of highly lateralized coding of linear head movements during late development.

  18. Gaze stabilization exercises derive sensory reweighting of vestibular for postural control.

    Science.gov (United States)

    Ueta, Yusuke; Matsugi, Akiyoshi; Oku, Kosuke; Okuno, Kojiro; Tamaru, Yoshiki; Nomura, Shohei; Tanaka, Hiroaki; Douchi, Shinya; Mori, Nobuhiko

    2017-09-01

    [Purpose] The aim of this study was to investigate whether gaze stabilization exercise derives sensory reweighting of vestibular for upright postural control. [Subjects and Methods] Twenty-three healthy volunteers participated in this study. The center of pressure of the total trajectory length was measured before (pre), immediately after (post), and 10 min after (post10) gaze stabilization exercise, in the static standing position, with the eyes open or closed, on the floor or on foam rubber. The sensory contribution values of the visual, somatosensory, and vestibular systems were calculated using center of pressure of the total trajectory length value in these measuring conditions. [Results] The center of pressure of the total trajectory length on foam rubber in post and post10 were significantly lower than that in the pre. The sensory contribution values of vestibular in post10 stages were significantly higher than that in pre-stage. [Conclusion] Gaze stabilization exercise can improve the static body balance in a condition that particularly requires vestibular function. The possible mechanism involves increasing sensory contribution of the vestibular system for postural control by the gaze stabilization exercise, which may be useful to derive sensory reweighting of the vestibular system for rehabilitation.

  19. Gaze stabilization exercises derive sensory reweighting of vestibular for postural control

    Science.gov (United States)

    Ueta, Yusuke; Matsugi, Akiyoshi; Oku, Kosuke; Okuno, Kojiro; Tamaru, Yoshiki; Nomura, Shohei; Tanaka, Hiroaki; Douchi, Shinya; Mori, Nobuhiko

    2017-01-01

    [Purpose] The aim of this study was to investigate whether gaze stabilization exercise derives sensory reweighting of vestibular for upright postural control. [Subjects and Methods] Twenty-three healthy volunteers participated in this study. The center of pressure of the total trajectory length was measured before (pre), immediately after (post), and 10 min after (post10) gaze stabilization exercise, in the static standing position, with the eyes open or closed, on the floor or on foam rubber. The sensory contribution values of the visual, somatosensory, and vestibular systems were calculated using center of pressure of the total trajectory length value in these measuring conditions. [Results] The center of pressure of the total trajectory length on foam rubber in post and post10 were significantly lower than that in the pre. The sensory contribution values of vestibular in post10 stages were significantly higher than that in pre-stage. [Conclusion] Gaze stabilization exercise can improve the static body balance in a condition that particularly requires vestibular function. The possible mechanism involves increasing sensory contribution of the vestibular system for postural control by the gaze stabilization exercise, which may be useful to derive sensory reweighting of the vestibular system for rehabilitation. PMID:28931974

  20. Objective vestibular testing of children with dizziness and balance complaints following sports-related concussions.

    Science.gov (United States)

    Zhou, Guangwei; Brodsky, Jacob R

    2015-06-01

    To conduct objective assessment of children with balance and vestibular complaints following sports-related concussions and identify the underlying deficits by analyzing laboratory test outcomes. Case series with chart review. Pediatric tertiary care facility. Medical records were reviewed of 42 pediatric patients with balance and/or vestibular complaints following sports-related concussions who underwent comprehensive laboratory testing on their balance and vestibular function. Patients' characteristics were summarized and results analyzed. More than 90% of the children with protracted dizziness or imbalance following sports-related concussion had at least 1 abnormal finding from the comprehensive balance and vestibular evaluation. The most frequent deficit was found in dynamic visual acuity test, followed by Sensory Organization Test and rotational test. Patient's balance problem associated with concussion seemed to be primarily instigated by vestibular dysfunction. Furthermore, semicircular canal dysfunction was involved more often than dysfunction of otolith organs. Yet, children experienced a hearing loss following sports-related concussion. Vestibular impairment is common among children with protracted dizziness or imbalance following sports-related concussion. Our study demonstrated that proper and thorough evaluation is imperative to identify these underlying deficits and laboratory tests were helpful in the diagnosis and recommendation of following rehabilitations. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  1. Developmental maturation of ionotropic glutamate receptor subunits in rat vestibular nuclear neurons responsive to vertical linear acceleration.

    Science.gov (United States)

    Lai, Suk-King; Lai, Chun-Hong; Tse, Yiu-Chung; Yung, Ken K L; Shum, Daisy K Y; Chan, Ying-Shing

    2008-12-01

    We investigated the maturation profile of subunits of ionotropic glutamate receptors in vestibular nuclear neurons that were activated by sinusoidal linear acceleration along the vertical plane. The otolithic origin of Fos expression in these neurons was confirmed as a marker of functional activation when labyrinthectomized and/or stationary control rats contrasted by showing sporadically scattered Fos-labeled neurons in the vestibular nuclei. By double immunohistochemistry for Fos and one of the receptor subunits, otolith-related neurons that expressed either alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate or N-methyl-d-aspartate subunits were first identified in the medial vestibular nucleus, spinal vestibular nucleus and Group x by postnatal day (P)7, and in the lateral vestibular nucleus and Group y by P9. No double-labeled neurons were found in the superior vestibular nucleus. Within each vestibular subnucleus, these double-labeled neurons constituted approximately 90% of the total Fos-labeled neurons. The percentage of Fos-labeled neurons expressing the GluR1 or NR2A subunit showed developmental invariance in all subnuclei. For Fos-labeled neurons expressing the NR1 subunit, similar invariance was observed except that, in Group y, these neurons decreased from P14 onwards. For Fos-labeled neurons expressing the GluR2, GluR2/3, GluR4 or NR2B subunit, a significant decrease was found by the adult stage. In particular, those expressing the GluR4 subunit showed a two- to threefold decrease in the medial vestibular nucleus, spinal vestibular nucleus and Group y. Also, those expressing the NR2B subunit showed a twofold decrease in Group y. Taken together, the postsynaptic expression of ionotropic glutamate receptor subunits in different vestibular subnuclei suggests that glutamatergic transmission within subregions plays differential developmental roles in the coding of gravity-related vertical spatial information.

  2. Vestibular Rehabilitation in a Patient with Whiplash-associated Disorders

    Directory of Open Access Journals (Sweden)

    Kwo-Shieng Tuo

    2006-12-01

    Full Text Available Whiplash-associated disorders are characterized by multiple physical complaints after a flexion-extension trauma to the neck. They are difficult to treat, and they often result in great impact on the patient's quality of life. In this paper, the comprehensive treatment of a patient with whiplash-associated disorders is presented. The purpose is to highlight the importance of accurate diagnosis and appropriate treatment plans to improve patients' quality of life. This 23-year-old woman experienced a traffic accident which caused severely painful neck disability, numbness over bilateral upper limbs, dizziness, double vision and loss of balance. Among these symptoms, dizziness was the problem that bothered the patient most. She received a comprehensive rehabilitation program including physical modalities, trigger point injections for relief of pain, as well as a vestibular rehabilitation program, which included exercises challenging and improving her balance function, head-eye coordination exercise, visual-ocular control exercise and sensory substitution-promoting exercises. She resumed her previous full-time work after 3 weeks of treatment. This successfully treated case illustrates the importance of correct diagnosis and appropriate treatment for patients who suffer from whiplash-associated disorders.

  3. Vestibular rehabili