Journal of Vestibular Research - Volume 26, issue 4

Authors: Laurell, Göran | Furman, Joseph M.

Article Type: Announcement

DOI: 10.3233/VES-160592

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 341-341, 2016

Authors: Holly, Jan E. | Masood, M. Arjumand | Bhandari, Chiran S.

Article Type: Research Article

Abstract: Head movements during sustained rotation can cause angular cross-coupling which leads to tumbling illusions. Even though angular vectors predict equal magnitude illusions for head movements in opposite directions, the magnitudes of the illusions are often surprisingly asymmetric, such as during leftward versus rightward yaw while horizontal in a centrifuge. This paper presents a comprehensive investigation of the angular-linear stimulus combinations from eight different published papers in which asymmetries were found. Interactions between all angular and linear vectors, including gravity, are taken into account to model the three-dimensional consequences of the stimuli. Three main results followed. First, for every pair of …head yaw movements, an asymmetry was found in the stimulus itself when considered in a fully three-dimensional manner, and the direction of the asymmetry matched the subjectively reported magnitude asymmetry. Second, for pitch and roll head movements for which motion sickness was measured, the stimulus was found symmetric in every case except one, and motion sickness generally aligned with other factors such as the existence of a head rest. Third, three-dimensional modeling predicted subjective inconsistency in the direction of perceived rotation when linear and angular components were oppositely-directed, and predicted surplus illusory rotation in the direction of head movement. Show more

Keywords: Self-motion perception, modeling, centrifugation, coriolis cross-coupling, artificial gravity

DOI: 10.3233/VES-160585

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 343-358, 2016

Authors: Ciardo, A. | El Assawy, N. | Mauro, S. | Priano, L.

Article Type: Research Article

Abstract: OBJECTIVE: To analyze and model the effects of acoustic stimulus duration on cervical vestibular evoked myogenic potentials (cVEMPs). DESIGN: Subjects with normal hearing and no vestibular or cervical disorders were tested using 1 kHz tone bursts (TBs) of different durations to evoke cVEMPs from the ipsilateral sternocleidomastoid muscle. VEMP modeling was performed in Labview. RESULTS: The increase in TB duration initially resulted in a non-linear increase in cVEMP amplitude, followed by more complex cVEMP modifications that were mainly related to the appearance of a new wave (nX) that interfered with n23. With long TBs there were …two distinct negative peaks with an identical threshold, suggesting a common vestibular nature. A two-level inhibition model qualitatively accounted for the two distinct negative peaks. However, good fitting of the cVEMP waveform required a multi-level model that included an excitatory phase after the inhibitory period. CONCLUSIONS: The two negative components (n23 and nX) observed in cVEMPs elicited by long TBs may result from the involvement of two different pathways with different dynamics or a single pathway with quick adaptation in the activity along the vestibulo-collic arc. Excitatory activity following the period of inhibition may represent rebound activity at the motor unit level. Show more

Keywords: VEMP, tone burst, model, fitting

DOI: 10.3233/VES-160586

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 359-374, 2016

Authors: Mantokoudis, Georgios | Saber Tehrani, Ali S. | Wozniak, Amy | Eibenberger, Karin | Kattah, Jorge C. | Guede, Cynthia I. | Zee, David S. | Newman-Toker, David E.

Article Type: Research Article

Abstract: OBJECTIVE: The video head impulse test (HIT) measures vestibular function (vestibulo-ocular reflex [VOR] gain – ratio of eye to head movement), and, in principle, could be used to make a distinction between central and peripheral causes of vertigo. However, VOG recordings contain artifacts, so using unfiltered device data might bias the final diagnosis, limiting application in frontline healthcare settings such as the emergency department (ED). We sought to assess whether unfiltered data (containing artifacts) from a video-oculography (VOG) device have an impact on VOR gain measures in acute vestibular syndrome (AVS). METHODS: This cross-sectional study compared VOG …HIT results ‘unfiltered’ (standard device output) versus ‘filtered’ (artifacts manually removed) and relative to a gold standard final diagnosis (neuroimaging plus clinical follow-up) in 23 ED patients with acute dizziness, nystagmus, gait disturbance and head motion intolerance. RESULTS: Mean VOR gain assessment alone (unfiltered device data) discriminated posterior inferior cerebellar artery (PICA) strokes from vestibular neuritis with 91% accuracy in AVS. Optimal stroke discrimination cut points were bilateral VOR gain >0.7099 (unfiltered data) versus >0.7041 (filtered data). For PICA stroke sensitivity and specificity, there was no clinically-relevant difference between unfiltered and filtered data–sensitivity for PICA stroke was 100% for both data sets and specificity was almost identical (87.5% unfiltered versus 91.7% filtered). More impulses increased gain precision. CONCLUSIONS: The bedside HIT remains the single best method for discriminating between vestibular neuritis and PICA stroke in patients presenting AVS. Quantitative VOG HIT testing in the ED is associated with frequent artifacts that reduce precision but not accuracy. At least 10–20 properly-performed HIT trials per tested ear are recommended for a precise VOR gain estimate. Show more

Keywords: Eye movement measurements, vestibulo-ocular reflex, vertigo, vestibular neuritis, stroke, diagnosis

DOI: 10.3233/VES-160587

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 375-385, 2016

Authors: Ribeyre, Laurence | Spitz, Elisabeth | Frère, Julien | Gauchard, Gerome | Parietti-Winkler, Cécile

Article Type: Research Article

Abstract: BACKGROUND : Various individual factors have been described to influence postural performances related to vestibular schwannoma. However, psychological factors may also be involved in postural variations. OBJECTIVE : To identify relationships between postural performances, illness perceptions, coping, anxiety-depression and quality of life of patients with vestibular schwannoma. METHODS : Twenty-six patients who were scheduled for a surgical removal of a vestibular schwannoma underwent posturography tests and were asked to complete psychological questionnaires three days prior to surgery. The Sensory Organization Test, the Illness Perceptions Questionnaire-Revised, the Brief-COPE, the Hospital Anxiety Depression Scale and the World Health Organization …Quality of Life instrument were used for assessments. Correlations between posturography and psychological questionnaires were calculated. RESULTS : Balance disorders were associated with (i) impaired quality of life of patients, (ii) anxiety and depression affects, (iii) greater daily consequences, and with (iv) denial coping response. CONCLUSIONS : Given the association between balance disorders and psychological factors, health practitioners should be attentive to the deterioration of both aforementioned issues. Show more

Keywords: Vestibular schwannoma, postural performances, illness perceptions, coping, anxiety-depression, quality of life

DOI: 10.3233/VES-160588

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 387-394, 2016

Authors: Wettstein, V.G. | Weber, K.P. | Bockisch, C.J. | Hegemann, S.C.

Article Type: Research Article

Abstract: BACKGROUND: Both the dynamic visual acuity (DVA) test and the video head-impulse test (vHIT) are fast and simple ways to assess peripheral vestibulopathy. After losing peripheral vestibular function, some patients show better DVA performance than others, suggesting good compensatory mechanisms. It seems possible that compensatory covert saccades could be responsible for improved DVA. OBJECTIVE: To investigate VOR gain and compensatory saccades with vHIT and compare them to the DVA of patients with unilateral peripheral vestibulopathy. METHODS: VOR gain deficit and compensatory saccades were measured with vHIT. VOR gain was calculated for each trial as mean …eye velocity divided by mean head velocity during 4 samples between 24 ms – 40 ms after peak head acceleration. DVA was then assessed. VHIT was analyzed for percentage of covert saccades and for cumulative overt saccade amplitude. Twenty-four patients with unilateral vestibular deficit were included. A control group of 113 healthy subjects provided normal data. RESULTS: On the affected side, pathologic values for DVA (mean 0.83 logMAR±0.25 SD) and VOR gain (mean 0.16±0.13) were obtained, whereas the healthy side showed normal values (0.53 logMAR±0.15 for DVA and 0.89±0.18 for VOR gain). Yet, DVA performance on the affected side was significantly better in patients with higher covert saccade percentage (p  = 0.012) and lower cumulative overt saccade amplitude (p  < 0.001). CONCLUSION: Compensatory covert saccades seen in vHIT correlate with improved performance of DVA-testing in patients with unilateral peripheral vestibular loss. Hence, in addition to testing peripheral vestibulopathy, our results indicate a way for assessing rehabilitatory compensation in such patients by DVA in addition to vHIT. Show more

Keywords: Vestibulopathy, compensatory saccades, head impulse test, dynamic visual acuity

DOI: 10.3233/VES-160591

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 395-402, 2016

Authors: Chiarella, G. | Petrolo, C. | Riccelli, R. | Giofrè, L. | Olivadese, G. | Gioacchini, F.M. | Scarpa, A. | Cassandro, E. | Passamonti, L.

Article Type: Research Article

Abstract: BACKGROUND: Chronic subjective dizziness (CSD) is characterized by persistent dizziness, unsteadiness, and hypersensitivity to one’s own motion or exposure to complex visual stimuli. CSD may be triggered, in predisposed individuals with specific personality traits, by acute vestibular diseases. CSD is also thought to arise from failure to re-establish normal balance strategies after resolution of acute vestibular events which may be modulated by diathesis to develop anxiety and depression. OBJECTIVE: To confirm the role of personality traits linked to anxiety and depression (i.e., neuroticism, introversion, low openness) as predisposing factors for CSD and to evaluate how individual differences …in these personality traits are associated with CSD severity. METHODS: We compared 19 CSD patients with 24 individuals who had suffered from periferal vestibular disorders (PVD) (i.e., Benign Paroxysmal Postural Vertigo or Vestibular Neuritis) but had not developed CSD as well as with 25 healthy controls (HC) in terms of personality traits, assessed via the NEO-PI-R questionnaire. RESULTS: CSD patients, relative to PVD patients and HCs, scored higher on the anxiety facet of neuroticism. Total neuroticism scores were also significantly associated with dizziness severity in CSD patients but not PVD patients. CONCLUSIONS: Pre-existing anxiety-related personality traits may promote and sustain the initial etiophatogenetic mechanisms linked with the development of CSD. Targeting anxiety-related mechanisms in CSD may be therefore a promising way to reduce the disability associated with CSD. Show more

Keywords: Chronic dizziness, CSD, anxiety, introversion, openness, neuroticism, vestibular

DOI: 10.3233/VES-160590

Citation: Journal of Vestibular Research, vol. 26, no. 4, pp. 403-408, 2016