Journal of Vestibular Research - Volume 27, issue 2-3

Authors: Aitken, Phillip | Zheng, Yiwen | Smith, Paul F.

Article Type: Research Article

Abstract: Bilateral vestibular loss (BVL) causes a unique behavioural syndrome in rodents, with symptoms such as locomotor hyperactivity and changes in exploratory behaviour. Many of these symptoms appear to be indirect consequences of the loss of vestibular reflex function and are difficult to explain. Although such symptoms have been reported before, there have been few systematic studies of the effects of BVL using automated digital tracking systems in which many behavioural symptoms can be measured simultaneously with high precision. In this study, data were obtained from rats with BVL induced by intratympanic sodium arsanilate injections (n  = 7) or sham injections (n … = 8) and their behaviour in the open field was measured at 3 days and 23 days post-injection using Ethovision™ tracking software. BVL rats demonstrated reduced thigmotaxis, with more time spent in the central zones. Twenty-three days post-injection, BVL animals showed increased locomotor activity in the open field. The increase in activity was also reflected in the number of transitions between each zone of the field. In addition to increased activity, BVL animals showed increased whole body rotations following lesions. Using linear discriminant analysis (LDA) and random forest classification (RFC), we were able to show that the indirect behavioural effects of BVL, excluding direct measurement of vestibular reflex function, could correctly predict whether animals had received a BVL with a high degree of accuracy at both day 3 and day 23 post-BVL (83% and 100% for LDA, and 100% and 100% for RFC, respectively). RFC has been similarly successful in classifying other hyperactivity syndromes such as attention deficit hyperactivity disorder. These results suggest that BVL results in a unique behavioural signature that can identify vestibular loss in rats even without direct vestibular reflex measurements. Show more

Keywords: Bilateral vestibular lesions, rat, ethovision, locomotor activity, behaviour

DOI: 10.3233/VES-170612

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 89-101, 2017

Authors: Wang, Linjie | Cao, Yi | Tan, Cheng | Zhao, Qi | He, Siyang | Niu, Dongbin | Tang, Guohua | Zou, Peng | Xing, Lei

Article Type: Research Article

Abstract: PURPOSE: Explore the different vestibular physiologic response retention patterns after Coriolis acceleration training in student pilots and extend the results for use with Chinese astronauts in the future. METHODS: Twelve healthy control male subjects were screened from males familiar with vestibular training and who physically resembled the astronauts. Fourteen student pilots were selected from 23 participants by rotational vestibular function tests. All subjects were exposed to five-day continuous or intermittent Coriolis acceleration training. Subjective motion sickness (MS) symptom scores, electrocardiography, electrogastrography (EGG), post-rotatory nystagmus and renin–angiotensin system responses were measured before, during and after rotational vestibular function …tests at different times after vestibular training. RESULTS: Subjects could tolerate 10 min or 15 min of vestibular with mild MS symptoms. Retention of vestibular autonomic responses (retention of MS symptom scores, heart rate variability, power density of EGG, variations in levels of arginine vasopressin) were approximately 1 week for control subjects and approximately 5 weeks for student pilots. Decreases in slow-phase velocity of post-rotatory nystagmus were maintained for 14 weeks for control subjects and 9 weeks for student pilots. CONCLUSIONS: Retention of the vestibulo-autonomic reaction after vestibular training was different for control subjects and student pilots. All parameters related to autonomic responses could be maintained at low levels after vestibular training for approximately 1 week for control subjects and approximately 5 weeks for student pilots. Uncoupling patterns between post-rotatory nystagmus and the vestibulo-autonomic reaction may be helpful in the design of clinical rehabilitation plans for balance-disorder patients and for exploration of artificial gravity in future space missions. Show more

Keywords: Vestibular training, heart rate variability, electrogastrography, post-rotatory nystagmus, pilots, motion sickness symptom score

DOI: 10.3233/VES-170608

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 103-112, 2017

Authors: Allum, J.H.J. | Langewitz, W. | Sleptsova, M. | Welge-Luessen, A. | Honegger, F. | Schatz, T.H. | Biner, C.L. | Maguire, C. | Schmid, D.A.

Article Type: Research Article

Abstract: BACKGROUND: Movements may be generated consistent with imagining one’s own body transformed or “disembodied” to a new position. Based on this concept we hypothesized that patients with objective balance deficits (obj-BD) would have altered neural transformation processes executing own body transformation (OBT) with functional consequences on balance control. Also we examined whether feeling unstable due to dizziness only (DO), without an obj-BD, also lead to an impaired OBT. METHODS: 32 patients with chronic dizziness were tested: 16 patients with obj-BD as determined by balance control during a sequence of stance and gait tasks, 16 patients with dizziness …only (DO). Patients and 9 healthy controls (HCs) were asked to replicate roll trunk movements of an instructor in a life size video: first, with spontaneously copied (SPO) or “embodied” egocentric movements (lean when the instructor leans); second, with “disembodied” or “transformed” movements (OBT) with exact replication – lean left when the instructor leans left. Onset latency of trunk roll, rise time to peak roll angle (interval), roll velocity, and amplitude were measured. RESULTS: SPO movements were always mirror-imaged. OBT task latencies were significantly longer and intervals shorter than for SPO tasks (p  < 0.03) for all groups. Obj-BD but not DO patients had more errors for the OBT task and, compared to HCs, had longer onset latencies (p  < 0.05) and smaller velocities (p  < 0.003) and amplitudes (p  < 0.001) in both the SPO and OBT tasks. Measures of DO patients were not significantly different from those of HCs. CONCLUSIONS: Mental transformation (OBT) and SPO copying abilities are impaired in subjects with obj-BD and dizziness, but not with dizziness only. We conclude that processing the neuropsychological representation of the human body (body schema) slows when balance control is deficient. Show more

Keywords: Own body transformation, body cognition, dizziness, vestibular deficits, balance control

DOI: 10.3233/VES-170613

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 113-125, 2017

Authors: Albathi, Monirah | Agrawal, Yuri

Article Type: Research Article

Abstract: BACKGROUND/OBJECTIVE: Several small studies in animals and humans have suggested a relationship between vestibular function and sleep. In this study, we evaluate the association between vestibular vertigo and sleep duration in a large, representative sample of US adults. METHODS: We used data from the National Health Interview Survey, which administered a Balance Supplement in 2008 in a sample of 20,950 adult respondents. We evaluated the cross-sectional association between vestibular vertigo (based on a well-validated definition) and sleep duration (defined as short <6 hours, normal 6–8 hours, and long >8 hours). We performed multiple and multinomial logistic regression analyses to …estimate the odds ratio and relative risk ratio (RRR) of impaired sleep duration compared to normal sleep duration associated with vestibular vertigo. Analyses were adjusted for demographic, lifestyle and health behavior characteristics as well as relevant comorbid conditions. RESULTS: Thirty percent of individuals with vestibular vertigo reported abnormal sleep duration (15.5% short duration and 14.8% long duration). In adjusted analyses, individuals with vestibular vertigo had a 1.75 (95% CI 1.45–2.11) RRR of having short sleep duration compared to individuals without vestibular vertigo, and a 1.55 (95% CI 1.26–1.91) RRR of having long sleep duration compared to individuals without vestibular vertigo. CONCLUSION: This study presents epidemiologic evidence to support the association between vestibular function and sleep duration. Individuals with vestibular vertigo had a higher RRR for abnormally short or long sleep duration. Further work is needed to evaluate the causal direction(s) of this association. Show more

Keywords: Vestibular vertigo, vestibular system, sleep duration, National Health Interview Survey

DOI: 10.3233/VES-170617

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 127-135, 2017

Authors: Williams, Grace | Sarig-Bahat, Hilla | Williams, Katrina | Tyrrell, Ryan | Treleaven, Julia

Article Type: Research Article

Abstract: OBJECTIVE: Research has consistently shown cervical kinematic impairments in subjects with persistent neck pain (NP). It could be reasoned that those with vestibular pathology (VP) may also have altered kinematics since vestibular stimulation via head movement can cause dizziness and visual disturbances. However, this has not been examined to date. This pilot study investigated changes in cervical kinematics between asymptomatic control, NP and VP subjects using a Virtual Reality (VR) system. It was hypothesised that there would be altered kinematics in VP subjects, which might be associated with dizziness and visual symptoms. DESIGN: Pilot cross sectional observational …study. PARTICIPANTS: Twenty control, 14 VP and 20 NP subjects. INTERVENTION: Not applicable. MAIN OUTCOME MEASURES: Measures included questionnaires (neck disability index, pain on movement, dizziness and pain intensity, visual disturbances) and cervical kinematics (range, peak and mean velocity, smoothness, symmetry, and accuracy of cervical motion) using a virtual reality system. RESULTS: Results revealed significantly decreased mean velocity and symmetry of motion in both planes in those with NP but no differences in accuracy or range of motion. No significant differences were seen between VP subjects and asymptomatic controls. However, correlation analysis showed some moderate correlations between dizziness to selected kinematics in both the NP and the VP groups. CONCLUSIONS: These results support that cervical kinematics are altered in NP patients, with velocity most affected. There is potential for VP subjects to also have altered kinematics, especially those who experience dizziness. More research is required. Show more

Keywords: Kinematics, neck pain, vestibular, virtual reality

DOI: 10.3233/VES-170615

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 137-145, 2017

Authors: Beyazal Celiker, Fatma | Dursun, Engin | Celiker, Metin | Durakoglugil, Tugba | Beyazal, Mehmet | Inecikli, Mehmet Fatih | Ozgur, Abdulkadir | Terzi, Suat

Article Type: Research Article

Abstract: BACKGROUND: Vascular loops of the anterior-inferior cerebellar artery (AICA) at the cerebellopontine angle (CPA) are considered related to auditory-vestibular symptoms. Clinical association of these anatomical aberrations, which can be grouped together as vascular compression syndromes, is controversial. Magnetic resonance imaging (MRI) is widely used to visualize this anatomical region, given its high sensitivity and specificity. OBJECTIVE: To elucidate the clinical relationship of vertigo symptoms with vascular loop compression syndrome by evaluating the neurovascular contacts of the vestibulocochlear nerve (VCN) and AICA at the CPA and internal auditory canal via high-resolution MRI. METHODS: The study included …417 patients (178 with vertigo and 239 without vertigo) undergoing MRI for various clinical causes. MRI scans were assessed to study the presence of vascular abnormalities at the CPA. RESULTS: According to our findings, type 1 vascular variation was observed most frequently in both sides. MRI findings were similar for the patients with and without vertigo. CONCLUSIONS: Identifying the prevalence of the vascular loops of the AICA primarily depends on diagnostic technique, and our results identified a slightly higher prevalence than those of previous studies, which might be partly related to the high-sensitivity of 3-dimensional T2-weighted MRI. Show more

Keywords: Vascular loop, cerebellopontine angle, internal acoustic canal, vertigo, magnetic resonance imaging

DOI: 10.3233/VES-170616

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 147-153, 2017

Authors: Wenzel, Angela | Eck, Simon | Hülse, Kathrin | Rohr, Karl | Hörmann, Karl | Umbreit, Claudia | Hülse, Manfred | Hülse, Roland

Article Type: Research Article

Abstract: INTRODUCTION: Earlier work revealed that vHIT examination is often difficult to perform on very young children. In particular, the calibration of the system can be difficult, as active cooperation of the patient is required. Additionally, the patient must be able to follow the examiner’s instructions, which is challenging for very young children. Therefore, the aim of the present study was to develop and validate a new, software-based approach enabling vHIT testing of young children and infants. METHODS AND MATERIALS: Six patients (3 boys and 3 girls) aged 5–36 months were included in a prospective, monocentric study between …January 2015 and August 2015. The newly developed intuitive software enabled calibration of the eye position signal with the subjects fixating on animated animal graphics which were projected on a screen. Testing ten healthy adults validated this new calibration and measurement method. After calibration, a vHIT goggle (EyeSeeCam © ) was used to perform head impulses in the horizontal plane while the patient was watching a movie sitting on their parent’s lap or in a baby chair. At least 15 impulses to each side were obtained and the occurrence of refixation saccades was analyzed. All tests were performed by one of two experienced examiners. RESULTS: The new calibration method and modified test setup provided reproducible results for all patients tested. An increased incidence of artifacts was not observed. In 2 patients, more than one test was needed. None of the included children showed catch-up overt or catch-up covert saccades. There was no gain reduction of more than two standard deviations as compared to the normative results published in the literature on vHIT examinations of children. CONCLUSION: The proposed protocol allows vHIT testing in very young children and infants (aged 5 months to 3 years). The study emphasizes that vHIT is an easy and sensitive screening tool to evaluate vestibular function in children and should be used as the gold standard in pediatric vestibular assessment. Show more

Keywords: vHIT, hVOR, dizziness, infant, vestibular

DOI: 10.3233/VES-170611

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 155-162, 2017

Authors: Cleworth, Taylor W. | Carpenter, Mark G. | Honegger, Flurin | Allum, John H.J.

Article Type: Research Article

Abstract: BACKGROUND: Different analysis techniques are used to define vestibulo-ocular reflex (VOR) gain between eye and head angular velocity during the video head impulse test (vHIT). Comparisons would aid selection of gain techniques best related to head impulse characteristics and promote standardisation. OBJECTIVE: Compare and contrast known methods of calculating vHIT VOR gain. METHODS: We examined lateral canal vHIT responses recorded from 20 patients twice within 13 weeks of acute unilateral peripheral vestibular deficit onset. Ten patients were tested with an ICS Impulse system (GN Otometrics) and 10 with an EyeSeeCam (ESC) system (Interacoustics). Mean gain …and variance were computed with area, average sample gain, and regression techniques over specific head angular velocity (HV) and acceleration (HA) intervals. RESULTS: Results for the same gain technique were not different between measurement systems. Area and average sample gain yielded equally lower variances than regression techniques. Gains computed over the whole impulse duration were larger than those computed for increasing HV. Gain over decreasing HV was associated with larger variances. Gains computed around peak HV were smaller than those computed around peak HA. The median gain over 50–70 ms was not different from gain around peak HV. However, depending on technique used, the gain over increasing HV was different from gain around peak HA. Conversion equations between gains obtained with standard ICS and ESC methods were computed. For low gains, the conversion was dominated by a constant that needed to be added to ESC gains to equal ICS gains. CONCLUSIONS: We recommend manufacturers standardize vHIT gain calculations using 2 techniques: area gain around peak HA and peak HV. Show more

Keywords: Head impulse test, vestibulo-ocular reflex, unilateral peripheral vestibular loss, eye movement analysis techniques

DOI: 10.3233/VES-170614

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 163-172, 2017

Authors: Schubert, M.C. | Stitz, J. | Cohen, H.S. | Sangi-Haghpeykar, H. | Mulavara, A.P. | Peters, B.T. | Bloomberg, J.J.

Article Type: Research Article

Abstract: BACKGROUND: We have developed a non-invasive, behavioral measure of ocular alignment using a computer tablet, colored lenses, and touch screen software. OBJECTIVE: The goal of this study was to determine if these tests differentiate healthy controls from patients with vestibular disorders. METHODS: In the vertical alignment nulling test (VAN), subjects were asked to adjust a horizontal line that was offset vertically from a fixed horizontal line. In the torsional alignment nulling test (TAN) subjects were asked to adjust a line that was rotationally offset (i.e. clockwise) from a fixed horizontal line. We measured VAN and …TAN in 14 healthy controls and 8 patients with known vestibular disorders. RESULTS: Patients had significantly worse scores than controls on TAN, (mean 2.2 vs 0.75, p  = 0.01), and no differences for scores compared to controls on VAN, (mean 0.4 vs 0.8, p  = 0.07). CONCLUSIONS: These results suggest that TAN, and possibly VAN, have potential for identifying misalignments in ocular position. After further technical development these tests might be useful in the future for screening patients in facilities that are not equipped to perform cervical and ocular vestibular evoked myogenic potentials. Show more

Keywords: Utricle, saccule, spatial orientation, vestibular, vestibular evoked myogenic potentials

DOI: 10.3233/VES-170618

Citation: Journal of Vestibular Research, vol. 27, no. 2-3, pp. 173-176, 2017