Journal of Vestibular Research - Volume 23, issue 4-5

Authors: Luxa, Nicholas | Salanova, Michele | Schiffl, Gudrun | Gutsmann, Martina | Besnard, Stéphane | Denise, Pierre | Clarke, Andrew | Blottner, Dieter

Article Type: Research Article

Abstract: Background: The vestibular system undergoes considerable modification during spaceflight [5]. This is paralleled by microgravity-induced muscle atrophy [6]. However, the possibility of vestibulo-autonomic regulatory mechanisms affecting skeletal muscle structure and function have not yet been addressed. Objective: We hypothesise that the vestibular system affects anti-gravitational skeletal muscle phenotype composition, size and the transcriptional factor called nuclear factor of activated T cells (NFATc1). Methods: In a laboratory study, we examined the morphological and histochemical properties including intramyocellular NFATc1 changes in slow-type soleus muscle of chemically labyrinthectomized rats (VLx; n=8) compared to a control group (Sham; …n=6) after a period of one month. Results and conclusion: Neurochemical vestibular deafferentation resulted in smaller myofibre sizes, altered myofibre phenotype composition, high yields of hybrid fibre formation, and reduced myonuclear NFATc1 accumulation as signs of slow-type myofibre atrophy, myofibre type remodelling, and altered nuclear transcriptional activity in the postural soleus muscle of rats. We propose that vestibulo-autonomic modification of skeletal muscles occurs during prolonged microgravity. Our findings are likely to have implications for vestibular rehabilitation in clinical settings. Show more

Keywords: Labyrinthectomy (vestibular lesion), skeletal muscle soleus, NFATc1 (NFAT2)

DOI: 10.3233/VES-130499

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 187-193, 2013

Authors: Deshpande, Nandini | Tourtillott, Brandon M. | Peters, Brian T. | Bloomberg, Jacob J.

Article Type: Research Article

Abstract: This study examined effects of aging, head-trunk coupling (HTcoupling) and walking speed on dynamic visual acuity (DVA) at near and far viewing distances. Ten healthy participants were recruited in 3 groups; young: 20–33 years, Older1: 65–74 years, Older2: 75–85 years. The binocular DVA was measured while walking on a treadmill at 0.75 and 1.5 m/s speeds. The optotype display was placed at 0.5 m for NearDVA and at 3.0 m for FarDVA. On randomly selected trials, HTcoupling was achieved by using a collar. A mix-factor ANOVA (age-group x HTcoupling x speed) was performed separately for the Near and FarDVA. NearDVA …declined with HTcoupling (p=0.021). Additionally, NearDVA worsened at the faster speed (p< 0.001). At 1.5 m/s speed the differences between Young and Older2 groups were significant (p=0.012) and those between Older1 and Older2 were marginal (p=0.085). FarDVA declined at the faster speed (p< 0.001) with no effect of HTcoupling or age-group. NearDVA is more sensitive to normal aging process. These age-related deficits become more apparent at higher walking speeds. Effect of HTcoupling on NearDVA suggests a possible additive effect of insufficient dampening of the vertical movement of the overall head-trunk complex and inability of the linear vestibulo-ocular reflex to compensate for the consequent high discrepancy. Show more

Keywords: Dynamic visual acuity, aging, vestibulo-occular reflex, locomotion

DOI: 10.3233/VES-130500

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 195-201, 2013

Authors: Paillard, A.C. | Quarck, G. | Paolino, F. | Denise, P. | Paolino, M. | Golding, J.F. | Ghulyan-Bedikian, V.

Article Type: Research Article

Abstract: Several studies have suggested that anxiety may play a role in motion sickness susceptibility (MSS) variability. This study aimed to assess motion sickness susceptibility in healthy subjects and chronic vestibular patients and to investigate its relationship to gender, age and trait-anxiety. Healthy subjects (n=167) and chronic dizzy patients with various vestibulopathies (n=94), aged from 20 to 92 years old, were asked to complete Motion Sickness Susceptibility questionnaire (MSSQ) and trait-anxiety questionnaire (STAI-B). When patients were divided into those who had vestibular loss (n=51) vs. patients without vestibular loss (n=43), the MSSQ scores (mean ± SD) for patients with vestibular loss …(18.8 ± 30.9) were lower than healthy subjects (36.4 ± 34.8), who were lower than vestibular patients without vestibular loss (59.0 ± 39.7). These significant differences could not be explained by gender, age, trait-anxiety, or interaction. Women had higher MSS than men, and MSS declined with age for healthy subjects and vestibular patients. The overall relationship between anxiety and MSS scores was weak and only reached significance in healthy subjects. These results support the conclusion that the vestibular system is heavily involved in MSS and that trait-anxiety may play a role in MSS but only in healthy subjects. Show more

Keywords: Anxiety, vestibular, dizziness, age, gender

DOI: 10.3233/VES-130501

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 203-209, 2013

Authors: Kitajima, Naoharu | Kobayashi, Noriko | Otsuka, Koji | Ogawa, Yasuo | Inagaki, Taro | Ichimura, Akihide | Suzuki, Mamoru

Article Type: Research Article

Abstract: Pupillary dilation in response to sound stimuli is well established and generally represents a startle reflex to sound. We previously reported that auditory-pupillary responses (APRs) persist with bilateral deafness, and that the pathways mediating APRs involve not only the cochlea but also otolith organs, especially the saccule. Here, we evaluated the vestibulo-autonomic responses in vestibular neuritis (VN) by assessing APRs. Twelve young healthy volunteers without a history of hearing and equilibrium problems and 10 VN patients participated. To clarify the relationship between APRs and vestibular function, especially otolith function, we performed caloric and vestibular-evoked myogenic response testing on VN patients. …In normal subjects, we examined APRs when delivering sound stimuli to both sides. In VN patients, we examined APRs when delivering stimuli simultaneously to both sides, to the affected side alone, and then to the unaffected side alone. With binaural stimulation, the pupillary index (PI) – the rate of dilation – of VN patients significantly differed from those of normal subjects. Moreover, in VN patients, PIs of the affected sides were significantly larger than those of the unaffected sides. Our study provides evidence that examining APRs may be useful for evaluating vestibulo-autonomic reflexes, especially otolith-autonomic reflexes. Show more

Keywords: Auditory-pupillary response, vestibulo-autonomic response, vestibular neuritis, otolith function

DOI: 10.3233/VES-130497

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 211-216, 2013

Authors: Kim, Soo-Chan | Kim, Mi Joo | Kim, Nambeom | Hwang, Jong Hyun | Han, Gyu Cheol

Article Type: Research Article

Abstract: Background and objectives: The ability of conventional diagnostic equipment to monitor feelings of dizziness experienced during daily activities is limited. Our goal is to develop an ambulatory multipurpose device for monitoring balance to prevent falling in daily life. Materials and methods: A three-axis accelerometers and gyroscope sensors were attached to the head, pelvis, and legs of vestibular neuritis (VN) patients or age-, height-, and body weight-matched healthy volunteers. The sum of the deviations for the scalar value of acceleration [signal vector magnitude, SVM (g)] and angular velocity (°/s) was measured using the modified Romberg test. …Results: The repeated measure ANOVA model with acceleration showed a greater group difference (p < 0.001) than that with angular velocity (p < 0.01). There was no significant interaction effect within-subjects factor between replication and groups (p < 0.178). SVM within the VN group significantly increased for all sensor locations compared to the control group (p < 0.01). Strong correlations between measurements taken at head and pelvis as sensor location were observed for both groups (VN/control, r=0.68/r=072). Conclusion: The SVM appears to accurately assess balance while standing, even repetitive measurement or any location in body. Show more

Keywords: Dizziness, acceleration, balance, monitoring, falling

DOI: 10.3233/VES-130489

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 217-225, 2013

Authors: Marchetti, Gregory F. | Bellanca, Jennica | Whitney, Susan L. | Lin, James Chia-Cheng | Musolino, Mark C. | Furman, Gabriel R. | Redfern, Mark S.

Article Type: Research Article

Abstract: Background: Accelerometers are being used to assess postural control in adults, but there is little to support their reliability and validity. Objective: To estimate the test-retest reliability of the balance accelerometry measure (BAM) and to describe the known-groups validity of the BAM composite score. Methods: Two measures of standing postural sway were taken across six sensory (vision/stance surface) and motor stance (feet together or tandem) positions from eighteen patients with vestibular disorders and 84 healthy subjects. Test-retest reliability for postural sway was estimated across all conditions using intraclass correlation coefficient (ICC). A composite measure …of sway standardized to young healthy subjects on eyes open firm surface stance was compared between groups. Results: Test-retest reliability of postural sway was good (ICC ⩾ 0.74) under all sensory conditions except eyes closed/tandem stance, which was slight to poor. Analysis of the receiver operating characteristic curve for composite scores indicated significant accuracy at identification of subjects in the vestibular/balance disorder groups. Composite standard scores equal or greater than 21.1 identified subjects with vestibular disorders with an accuracy of 72% sensitivity and 68% specificity. Conclusion: The BAM displays good-excellent reliability for five of six sensory-motor conditions. The composite score appears to differentiate healthy from subjects with vestibular disorders. Show more

Keywords: Balance, postural control, accelerometer

DOI: 10.3233/VES-130490

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 227-235, 2013

Authors: Sibindi, Tafadzwa M. | Krasovsky, Tal | Feldman, Anatol G. | Dannenbaum, Elizabeth | Zeitouni, Anthony | Levin, Mindy F

Article Type: Research Article

Abstract: When arm and trunk segments are involved in reaching for objects within arm's reach, vestibulospinal pathways compensate for trunk motion influence on arm movement. This compensatory arm-trunk synergy is characterised by a gain coefficient of 0 to 1. Vestibular patients have less efficient arm-trunk synergies and lower gains. To assess the clinical usefulness of the gain measure, we used a portable ultrasound-based device to characterize arm-trunk coordination deficits in vestibular patients. Arm-trunk coordination without vision was measured in a Stationary Hand Task where hand position was maintained during trunk movement, and a Reaching Task with and without trunk motion. Twenty …unilateral vestibular patients and 16 controls participated. For the Stationary Hand task, patient gains ranged from g=0.94 (good compensation) to 0.31 (poor compensation) and, on average, were lower than in controls (patients: 0.67 ± 0.19; controls: 0.85 ± 0.07; p< 0.01). Gains were significantly correlated with clinical tests (Sensory Organization; r=0.62, p< 0.01, Foam Romberg Eyes Closed; r=0.65, p< 0.01). For the Reaching Task, blocking trunk movement during reaching modified hand position significantly more in patients (8.2 ± 4.3 cm) compared to controls (4.5 ± 1.7 cm, p< 0.02) and the amount of hand position deviation was correlated with the degree of vestibular loss in a sub-group (n=14) of patients. Measurement of the Stationary Task arm-trunk gain and hand deviations during the Reaching Task can help characterize sensorimotor problems in vestibular-deficient patients and track recovery following therapeutic interventions. The ultrasound-based portable device is suitable for measuring vestibulospinal deficits in arm-trunk coordination in a clinical setting. Show more

Keywords: Motor control, vestibular deficiency, rehabilitation, arm-trunk coordination, measurement

DOI: 10.3233/VES-130485

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 237-247, 2013

Authors: Egami, Naoya | Ushio, Munetaka | Yamasoba, Tatsuya | Yamaguchi, Takuhiro | Murofushi, Toshihisa | Iwasaki, Shinichi

Article Type: Research Article

Abstract: Objective: To estimate the sensitivity and specificity of vestibular evoked myogenic potentials (VEMPs) in comparison with caloric test in diagnosing Meniere's disease (MD) among patients with dizziness. Methods: Data were retrospectively collected from 1,170 consecutive patients who underwent vestibular tests. Among them, 114 patients were diagnosed as having unilateral definite MD. VEMPs in response to clicks and short tone burst stimulation as well as caloric tests were performed. The sensitivity and specificity of each test were evaluated. The results of each test were compared with hearing level and staging of MD. Results: The sensitivity …and specificity of VEMPs were 50.0% and 48.9%, while those of the caloric test were 37.7% and 51.2%, respectively. There was no significant difference in hearing level between patients appropriately or inappropriately identified by VEMPs, whereas there was a significant difference in those of the caloric test. Combined use of VEMP and caloric test increased the sensitivity to 65.8%. Conclusion: Although the sensitivity and specificity of VEMPs in diagnosing MD were not high, they were comparable to those of caloric test. VEMPs as well as caloric testing may give additional information as part of a diagnostic test battery for detecting vestibular abnormalities in MD. Show more

Keywords: Meniere's disease, endolymphatic hydrops, vestibular evoked myogenic potentials, caloric test, staging

DOI: 10.3233/VES-130484

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 249-257, 2013

Authors: Balci, Birgül Donmez | Akdal, Gülden | Yaka, Erdem | Angin, Salih

Article Type: Research Article

Abstract: Objective: To investigate the effects of two different rehabilitation programs in acute central vestibulopathy secondary to posterior circulation stroke. Method: A prospective randomized controlled study was conducted on 25 patients with posterior circulation stroke. Patients were instructed in routine balance and mobility exercises during the acute hospitalization period. At discharge, patients were assigned to either a rehabilitation or home exercise group. The home exercise group was instructed to perform the same exercise program provided in the course of hospitalization period. The rehabilitation group was randomized into the visual feedback posturography training or vestibular rehabilitation group. The balance …and gait performance were assessed with clinical and objective measurements before and after 6 weeks of training. Results: The balance and gait scores were significantly improved in both rehabilitation groups and in the home exercise group (p< 0.05), but no significant difference was found between the groups in terms of post-treatment values (p> 0.05). Conclusion: The improvements of balance and gait function in rehabilitation groups did not differ from the home exercise group. Rehabilitation programs were equally effective to improve the recovery in acute central vestibulopathy. Show more

Keywords: Acute stroke, posterior circulation, vestibular rehabilitation, balance

DOI: 10.3233/VES-130491

Citation: Journal of Vestibular Research, vol. 23, no. 4-5, pp. 259-267, 2013