Bilateral Vestibular Deficiency: Quality of Life and Economic Implications.

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Sun, Daniel Q; Ward, Bryan K; Semenov, Yevgeniy R; Carey, John P; Della Santina, Charles C

2014-06-01

Bilateral vestibular deficiency (BVD) causes chronic imbalance and unsteady vision and greatly increases the risk of falls; however, its effects on quality of life and economic impact are not well defined. To quantify disease-specific and health-related quality of life, health care utilization, and economic impact on individuals with BVD in comparison with those with unilateral vestibular deficiency (UVD). Cross-sectional survey study of patients with BVD or UVD and healthy controls at an academic medical center. Vestibular dysfunction was diagnosed by means of caloric nystagmography. Survey questionnaire. Health status was measured using the Dizziness Handicap Index (DHI) and Health Utility Index Mark 3 (HUI3). Economic burden was estimated using participant responses to questions on disease-specific health care utilization and lost productivity. Fifteen patients with BVD, 22 with UVD, and 23 healthy controls participated. In comparison with patients with UVD and controls, patients with BVD had significantly worse DHI (P work days (P life and imposes substantial economic burdens on individuals and society. These results underscore the limits of adaptation and compensation in BVD. Furthermore, they quantify the potential benefits of prosthetic restoration of vestibular function both to these individuals and to society.

Unilateral vestibular loss impairs external space representation.

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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.

Vestibular Evoked Myogenic Potential Produced by Bone-Conducted Stimuli: A Study on its Basics and Clinical Applications in Patients with Conductive and Sensorineural Hearing Loss and a Group with Vestibular Schawannoma.

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Mahdi, Parvane; Amali, Amin; Pourbakht, Akram; Karimi Yazdi, Alireza; Bassam, Ali

2013-06-01

Vestibular evoked myogenic potential (VEMP) has recently been broadly studied in vestibular disorders. As it is evoked by loud sound stimulation, even mild conductive hearing loss may affect VEMP results. Bone-conducted (BC) stimulus is an alternative stimulation for evoking this response. This study aims to assess the characteristics of BC-VEMP in different groups of patients. We performed a cross sectional analysis on 20 healthy volunteers with normal pure-tone audiometry as a control group; and on a group of patients consisted of 20 participants with conductive hearing loss, five with bilateral sensorineural hearing loss and four with vestibular schawannoma. AC and BC-VEMP were performed in all participants. In control group the VEMP responses to both kinds of stimuli had an acceptable morphology and consisted of p13 and n23 waves. Latency value of these main components in each type of stimulus was not significantly different (P>0.05). However, the mean amplitude was larger in BC modality than AC stimulation (P=0.025). In the group with conductive hearing loss, the VEMP response was absent in fifteen (46.87%) of the 32 ears using the AC method, whereas all (100%) displayed positive elicitability of VEMP by BC method. Normal VEMP responses in both stimuli were evoked in all patients with sensorineural hearing loss. In patients with unilateral vestibular schwannomas (VS), 2 (50.00%) had neither AC-VEMP nor BC-VEMP. Auditory stimuli delivered by bone conduction can evoke VEMP response. These responses are of vestibular origin and can be used in vestibular evaluation of patients with conductive hearing loss.

Vestibular Evoked Myogenic Potential Produced by Bone-Conducted Stimuli: A Study on its Basics and Clinical Applications in Patients With Conductive and Sensorineural Hearing Loss and a Group With Vestibular Schawannoma

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Parvane Mahdi

2013-06-01

Full Text Available Introduction: Vestibular evoked myogenic potential (VEMP has recently been broadly studied in vestibular disorders. As it is evoked by loud sound stimulation, even mild conductive hearing loss may affect VEMP results. Bone-conducted (BC stimulus is an alternative stimulation for evoking this response. This study aims to assess the characteristics of BC-VEMP in different groups of patients.   Materials and Methods: We performed a cross sectional analysis on 20 healthy volunteers with normal pure-tone audiometry as a control group; and on a group of patients consisted of 20 participants with conductive hearing loss, five with bilateral sensorineural hearing loss and four with vestibular schawannoma. AC and BC-VEMP were performed in all participants.   Results: In control group the VEMP responses to both kinds of stimuli had an acceptable morphology and consisted of p13 and n23 waves. Latency value of these main components in each type of stimulus was not significantly different (P>0.05. However, the mean amplitude was larger in BC modality than AC stimulation (P=0.025. In the group with conductive hearing loss, the VEMP response was absent in fifteen (46.87% of the 32 ears using the AC method, whereas all (100% displayed positive elicitability of VEMP by BC method. Normal VEMP responses in both stimuli were evoked in all patients with sensorineural hearing loss. In patients with unilateral vestibular schwannomas (VS, 2 (50.00% had neither AC-VEMP nor BC-VEMP. Conclusion:  Auditory stimuli delivered by bone conduction can evoke VEMP response. These responses are of vestibular origin and can be used in vestibular evaluation of patients with conductive hearing loss.

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

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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

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input.

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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

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

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Andreas Sprenger

2017-09-01

Full Text Available 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

Right-sided dominance of the bilateral vestibular system in the upper brainstem and thalamus.

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Dieterich, Marianne; Kirsch, V; Brandt, T

2017-10-01

MRI diffusion tensor imaging tractography was performed on the bilateral vestibular brainstem pathways, which run from the vestibular nuclei via the paramedian and posterolateral thalamic subnuclei to the parieto-insular vestibular cortex. Twenty-one right-handed healthy subjects participated. Quantitative analysis revealed a rope-ladder-like system of vestibular pathways in the brainstem with crossings at pontine and mesencephalic levels. Three structural types of right-left fiber distributions could be delineated: (1) evenly distributed pathways at the lower pontine level from the vestibular nuclei to the pontine crossing, (2) a moderate, pontomesencephalic right-sided lateralization between the pontine and mesencephalic crossings, and (3) a further increase of the right-sided lateralization above the mesencephalic crossing leading to the thalamic vestibular subnuclei. The increasing lateralization along the brainstem was the result of an asymmetric number of pontine and mesencephalic crossing fibers which was higher for left-to-right crossings. The dominance of the right vestibular meso-diencephalic circuitry in right-handers corresponds to the right-hemispheric dominance of the vestibular cortical network. The structural asymmetry apparent in the upper brainstem might be interpreted in relation to the different functions of the vestibular system depending on their anatomical level: a symmetrical sensorimotor reflex control of eye, head, and body mediated by the lower brainstem; a lateralized right-sided upper brainstem-thalamic function as part of the dominant right-sided cortical/subcortical vestibular system that enables a global percept of body motion and orientation in space.

Vestibular dysfunction in Turner syndrome: a case report.

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Baxter, Michael; Agrawal, Yuri

2014-02-01

Turner syndrome is a well-known cause of sensorineural hearing loss, and the lack of estrogen has been implicated in cochlear dysfunction. It has never been associated with vestibular dysfunction. We report a case of a patient with Turner syndrome who was found to have bilateral vestibular dysfunction based on video-oculography (VOG) testing. A single patient with a history of Turner syndrome who was found to have significant bilateral vestibular dysfunction. After noticing a deficit in the vestibulo-ocular reflexes on qualitative horizontal head impulse examination, the patient underwent VOG testing. VOG testing quantatively measures angular vestibulo-ocular reflex (AVOR) gain in the horizontal semicircular canal plane. AVOR gain represents the eye movement response to a head movement; in normal individuals the eye movement is fully compensatory and gain values are close to unity. VOG results showed AVOR gains of 0.29 and 0.36 on the right and left sides, respectively. We have presented a case of a woman with Turner syndrome with asymptomatic vestibular dysfunction demonstrated with VOG testing. Although there is a documented relationship between Turner syndrome and sensorineural hearing loss, there are no previous studies or case reports linking Turner syndrome and vestibular dysfunction. Additional research and added vigilance in monitoring Turner syndrome patients may be warranted.

Altered resting-state functional connectivity in patients with chronic bilateral vestibular failure

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Martin Göttlich

2014-01-01

Using whole brain resting-state connectivity analysis in BVF patients we show that enduring bilateral deficient or missing vestibular input leads to changes in resting-state connectivity of the brain. These changes in the resting brain are robust and task-independent as they were found in the absence of sensory stimulation and without a region-related a priori hypothesis. Therefore they may indicate a fundamental disease-related change in the resting brain. They may account for the patients' persistent deficits in visuo-spatial attention, spatial orientation and unsteadiness. The relation of increasing connectivity in the inferior parietal lobe, specifically SMG, to improvement of VOR during active head movements reflects cortical plasticity in BVF and may play a clinical role in vestibular rehabilitation.

Hearing loss in enlarged vestibular aqueduct and incomplete partition type II.

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Ahadizadeh, Emily; Ascha, Mustafa; Manzoor, Nauman; Gupta, Amit; Semaan, Maroun; Megerian, Cliff; Otteson, Todd

The purpose of this work is to identify the role of incomplete partition type II on hearing loss among patients with enlarged vestibular aqueduct (EVA). EVA is a common congenital inner ear malformation among children with hearing loss, where vestibular aqueduct morphology in this population has been shown to correlate to hearing loss. However, the impact of incomplete partition between cochlear turns on hearing loss has not been, despite meaningful implications for EVA pathophysiology. A retrospective review of radiology reports for patients who had computed tomography (CT) scans with diagnoses of hearing loss at a tertiary medical center between January 2000 and June 2016 were screened for EVA. CT scans of the internal auditory canal (IAC) for those patients with EVA were examined for evidence of incomplete partition type II (IP-II), measurements of midpoint width and operculum width a second time, and patients meeting Cincinnati criteria for EVA selected for analysis. Statistical analysis including chi-square, Wilcoxon rank-sum, and t-tests were used to identify differences in outcomes and clinical predictors, as appropriate for the distribution of the data. Linear mixed models of hearing test results for all available tests were constructed, both univariable and adjusting for vestibular aqueduct morphometric features, with ear-specific intercepts and slopes over time. There were no statistically significant differences in any hearing test results or vestibular aqueduct midpoint and operculum widths. Linear mixed models, both univariable and those adjusting for midpoint and operculum widths, did not indicate a statistically significant effect of incomplete partition type II on hearing test results. Hearing loss due to enlarged vestibular aqueduct does not appear to be affected by the presence of incomplete partition type II. Our results suggest that the pathophysiological processes underlying hearing loss in enlarged vestibular aqueduct may not be a result of

Vestibular ablation and a semicircular canal prosthesis affect postural stability during head turns

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Thompson, Lara A.; Haburcakova, Csilla; Lewis, Richard F.

2016-01-01

In our study, we examined postural stability during head turns for two rhesus monkeys: one, single animal study contrasted normal and mild bilateral vestibular ablation and a second animal study contrasted severe bilateral vestibular ablation with and without prosthetic stimulation. The monkeys freely stood, unrestrained on a balance platform and made voluntary head turns between visual targets. To quantify each animals’ posture, motions of the head and trunk, as well as torque about the body’s center-of-mass, were measured. In the mildly ablated animal, we observed less foretrunk sway in comparison to the normal state. When the canal prosthesis provided electric stimulation to the severely ablated animal, it showed a decrease in trunk sway during head turns. Because the rhesus monkey with severe bilateral vestibular loss exhibited a decrease in trunk sway when receiving vestibular prosthetic stimulation, we propose that the prosthetic electrical stimulation partially restored head velocity information. Our results provide an indication that a semicircular canal prosthesis may be an effective way to improve postural stability in patients with severe peripheral vestibular dysfunction. PMID:27405997

Characteristics of vertigo and the affected vestibular nerve systems in idiopathic bilateral vestibulopathy.

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Fujimoto, Chisato; Kinoshita, Makoto; Kamogashira, Teru; Egami, Naoya; Sugasawa, Keiko; Yamasoba, Tatsuya; Iwasaki, Shinichi

2016-01-01

Vertigo attacks in IBV patients involving both the superior and inferior vestibular nerve systems were significantly more severe than vertigo attacks in patients with selective involvement of the inferior vestibular nerve system alone. To investigate the relationship between the frequency and duration of vertigo and the affected vestibular nerve system in idiopathic bilateral vestibulopathy (IBV). This study categorized 44 IBV patients into the following three sub-groups according to the affected vestibular nerve system: superior, inferior, and mixed type. These patients were also categorized into the following three sub-groups according to their clinical time course: progressive type showing no episodes of vertigo, sequential type showing recurrent vertigo attacks and single-attack type showing a single episode of vertigo. Ten, 11 and 23 patients were classified as the superior, the inferior, and the mixed type, respectively. Seventeen, 23, and four patients were classified as the progressive, the sequential, and the single-attack type, respectively. For the patients having one or more vertigo attacks, the duration of the vertigo attack was longer than 24 h in 69% of the mixed type, and the duration of vertigo in the mixed type was significantly longer than that in the inferior type (p < 0.05).

Effects of bilateral vestibular nucleus lesions on cardiovascular regulation in conscious cats.

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Mori, R L; Cotter, L A; Arendt, H E; Olsheski, C J; Yates, B J

2005-02-01

The vestibular system participates in cardiovascular regulation during postural changes. In prior studies (Holmes MJ, Cotter LA, Arendt HE, Cas SP, and Yates BJ. Brain Res 938: 62-72, 2002, and Jian BJ, Cotter LA, Emanuel BA, Cass SP, and Yates BJ. J Appl Physiol 86: 1552-1560, 1999), transection of the vestibular nerves resulted in instability in blood pressure during nose-up body tilts, particularly when no visual information reflecting body position in space was available. However, recovery of orthostatic tolerance occurred within 1 wk, presumably because the vestibular nuclei integrate a variety of sensory inputs reflecting body location. The present study tested the hypothesis that lesions of the vestibular nuclei result in persistent cardiovascular deficits during orthostatic challenges. Blood pressure and heart rate were monitored in five conscious cats during nose-up tilts of varying amplitude, both before and after chemical lesions of the vestibular nuclei. Before lesions, blood pressure remained relatively stable during tilts. In all animals, the blood pressure responses to nose-up tilts were altered by damage to the medial and inferior vestibular nuclei; these effects were noted both when animals were tested in the presence and absence of visual feedback. In four of the five animals, the lesions also resulted in augmented heart rate increases from baseline values during 60 degrees nose-up tilts. These effects persisted for longer than 1 wk, but they gradually resolved over time, except in the animal with the worst deficits. These observations suggest that recovery of compensatory cardiovascular responses after loss of vestibular inputs is accomplished at least in part through plastic changes in the vestibular nuclei and the enhancement of the ability of vestibular nucleus neurons to discriminate body position in space by employing nonlabyrinthine signals.

Vestibular neuritis: three-dimensional videonystagmography and vestibular evoked myogenic potential results.

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Chen, C W; Young, Y H; Wu, C H

2000-10-01

Eight patients diagnosed with vestibular neuritis received the newly developed three-dimensional videonystagmography (3D VNG) and vestibular evoked myogenic potential (VEMP) examination in order to localize the lesion site. Two (25%) of the 8 patients exhibited spontaneous nystagmus with 3 components, indicating that both the horizontal semicircular canal (HSCC) and anterior semicircular canal (ASCC) were affected. The remaining 6 patients (75%) displayed only horizontal nystagmus, meaning that only the HSCC was involved. Seven (88%) of the 8 patients had bilateral normal VEMPs, revealing sparing of the posterior semicircular canal (PSCC). In a comparative study, another seven patients with vestibular neuritis 1 year post-treatment also received the caloric test, 3D VNG and VEMP examination. Only one patient exhibited spontaneous nystagmus. An absent caloric response of the lesioned side persisted in 5 (71%) of the 7 patients. However, all patients showed normal VEMPs bilaterally. 3D VNG and VEMP examination indicates that vestibular neuritis mainly affects the superior division of the vestibular nerve, which innervates the HSCC and ASCC. Meanwhile, the function of the PSCC and saccule, innervated by the inferior vestibular nerve, is preserved.

Beyond dizziness: virtual navigation, spatial anxiety and hippocampal volume in bilateral vestibulopathy

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Olympia eKremmyda

2016-03-01

Full Text Available Bilateral vestibulopathy (BVP is defined as the impairment or loss of function of either the labyrinths or the eighth nerves. Patients with total BVP due to bilateral vestibular nerve section exhibit difficulties in spatial memory and navigation and show a loss of hippocampal volume. In clinical practice, most patients do not have a complete loss of function but rather an asymmetrical residual functioning of the vestibular system. The purpose of the current study was to investigate navigational ability and hippocampal atrophy in BVP patients with residual vestibular function. Fifteen patients with BVP and a group of age- and gender- matched healthy controls were examined. Self-reported questionnaires on spatial anxiety and wayfinding were used to assess the applied strategy of wayfinding and quality of life. Spatial memory and navigation were tested directly using a virtual Morris Water Maze Task. The hippocampal volume of these two groups was evaluated by voxel-based morphometry. In the patients, the questionnaire showed a higher spatial anxiety and the Morris Water Maze Task a delayed spatial learning performance. MRI revealed a significant decrease in the gray matter mid-hippocampal volume (Left: p = 0.006, Z = 4.58, Right: p < 0.001, Z = 3.63 and posterior parahippocampal volume (Right: p = 0.005, Z = 4.65, Left: p < 0.001, Z = 3.87 compared to those of healthy controls. In addition, a decrease in hippocampal formation volume correlated with a more dominant route-finding strategy. Our current findings demonstrate that even partial bilateral vestibular loss leads to anatomical and functional

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

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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.

Vertigo with sudden hearing loss: audio-vestibular characteristics.

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Pogson, Jacob M; Taylor, Rachael L; Young, Allison S; McGarvie, Leigh A; Flanagan, Sean; Halmagyi, G Michael; Welgampola, Miriam S

2016-10-01

Acute vertigo with sudden sensorineural hearing loss (SSNHL) is a rare clinical emergency. Here, we report the audio-vestibular test profiles of 27 subjects who presented with these symptoms. The vestibular test battery consisted of a three-dimensional video head impulse test (vHIT) of semicircular canal function and recording ocular and cervical vestibular-evoked myogenic potentials (oVEMP, cVEMP) to test otolith dysfunction. Unlike vestibular neuritis, where the horizontal and anterior canals with utricular function are more frequently impaired, 74 % of subjects with vertigo and SSNHL demonstrated impairment of the posterior canal gain (0.45 ± 0.20). Only 41 % showed impairment of the horizontal canal gains (0.78 ± 0.27) and 30 % of the anterior canal gains (0.79 ± 0.26), while 38 % of oVEMPs [asymmetry ratio (AR) = 41.0 ± 41.3 %] and 33 % of cVEMPs (AR = 47.3 ± 41.2 %) were significantly asymmetrical. Twenty-three subjects were diagnosed with labyrinthitis/labyrinthine infarction in the absence of evidence for an underlying pathology. Four subjects had a definitive diagnosis [Ramsay Hunt Syndrome, vestibular schwannoma, anterior inferior cerebellar artery (AICA) infarction, and traction injury]. Ischemia involving the common-cochlear or vestibulo-cochlear branches of the labyrinthine artery could be the simplest explanation for vertigo with SSNHL. Audio-vestibular tests did not provide easy separation between ischaemic and non-ischaemic causes of vertigo with SSNHL.

IgG4-Related Disease of Bilateral Temporal Bones.

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Li, Lilun; Ward, Bryan; Cocks, Margaret; Kheradmand, Amir; Francis, Howard W

2017-03-01

IgG4-related disease (IgG4-RD) is an idiopathic inflammatory condition that causes pseudotumor formation in single or multiple organs, including those of the head and neck. Temporal bone involvement is rare, with only 3 cases of unilateral temporal bone IgG4-RD described in the literature. We report the first known case of IgG4-RD of bilateral temporal bones and describe its clinical presentation, diagnosis, and treatment. The patient was a 52-year-old man with latent tuberculosis (TB) who presented with a 10-year history of bilateral profound hearing loss and vestibular dysfunction. Computed tomography and magnetic resonance imaging demonstrated bilateral labyrinthine destruction with invasion of the posterior fossa. Immunoglobulin level testing showed elevated total serum IgG levels with normal IgG4 levels. Bilateral mastoidectomies were performed, with biopsy samples demonstrating IgG4 staining with IgG4-positive plasma cells up to 40/HPF (high power field) on the right and 20/HPF on the left, consistent with bilateral IgG4-RD. IgG4-RD of bilateral temporal bones presents with chronic and progressive bilateral hearing loss and vestibular dysfunction. Clinical presentation and radiologic findings are nonspecific, and definitive diagnosis must be made with histopathology and immunostaining. Corticosteroids are therapeutic, but surgical resection may be necessary for temporal bone IgG4-RD to improve long-term remission.

Achados vestibulares em usuários de aparelho de amplificação sonora individual Vestibular findings in hearing aid users

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Fabiane Paulin

2009-01-01

Full Text Available OBJETIVO: verificar os achados vestibulares em pacientes com perda auditiva neurossenssorial usuários de aparelho de amplificação sonora individual. MÉTODOS: vinte pacientes, 11 do sexo feminino e nove do sexo masculino, com idades entre 39 e 85 anos, com perda auditiva neurossenssorial bilateral de grau moderado e severo foram atendidos em uma Instituição de Ensino Superior e submetidos a uma anamnese, inspeção otológica, avaliação audiológica, imitanciometria e ao exame vestibular por meio da vectoeletronistagmografia. RESULTADOS: a dos 20 pacientes avaliados, 18 (90% apresentaram queixa de zumbido, 15 (75% queixa de tontura e oito (40% queixa de cefaléia; b houve predomínio de alteração na prova calórica e no sistema vestibular periférico; c o resultado do exame vestibular esteve alterado em 14 pacientes (70%, sendo, oito casos (40% de síndrome vestibular periférica irritativa e seis casos (30% de síndrome vestibular periférica deficitária; d verificou-se diferença significativa entre o resultado do exame vestibular e o tempo de uso do aparelho de amplificação sonora individual; e dos cinco pacientes que não referiram nenhum sintoma vestibular, quatro (80% apresentaram alteração no exame. CONCLUSÃO: ressalta-se a sensibilidade e importância do estudo funcional do sistema do equilíbrio neste tipo de população, uma vez que podem ocorrer alterações na avaliação labiríntica independente da presença de sintomas.PURPOSE: to check vestibular findings in patients with sensoneural hearing loss, hearing aid users. METHODS: 20 patients (eleven females and nine males aging from 39 to 85-year-old with bilateral sensorineural hearing loss, from moderate to severe degrees, were attended in a higher education institution evaluated by medical history, otological inspections, complete basic conventional audiological evaluations, acoustic impedance tests and vectoeletronystagmography. RESULTS: a from the 20 evaluated

Preoperative vestibular assessment protocol of cochlear implant surgery: an analytical descriptive study.

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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.

A Xenograft Model of Vestibular Schwannoma and Hearing Loss.

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Dinh, Christine T; Bracho, Olena; Mei, Christine; Bas, Esperanza; Fernandez-Valle, Cristina; Telischi, Fred; Liu, Xue-Zhong

2018-03-19

Microsurgical implantation of mouse merlin-deficient Schwann cells (MD-SC) into the cerebellopontine angle of immunodeficient rats will initiate tumor formation, hearing loss, and vestibular dysfunction. The progress in identifying effective drug therapies for treatment of Neurofibromatosis type II (NF2) is limited by the availability of animal models of VS that develop hearing loss and imbalance. A microsurgical technique for implanting MD-SCs onto the cochleovestibular nerve of rats was developed. Ten Rowett Nude rats were implanted with either ∼10 MD-SCs expressing luciferase (N = 5) or vehicle (N = 5). Rats received bioluminescence imaging, auditory brainstem response testing, and were observed for head tilt every 2 weeks after surgery, for a total of 6 weeks. Tumors were harvested and processed with hematoxylin & eosin staining and immunohistochemistry was performed for S100. Rats implanted with MD-SCs developed significantly higher tumor bioluminescence measurements and hearing threshold shifts at multiple frequencies by the 4th and 6th weeks post-implantation, compared with control rats. Rats implanted with MD-SCs also developed gross tumor. The tumor volume was significantly greater than nerve volumes obtained from rats in the control group. All rats with tumors developed a head tilt, while control rats had no signs of vestibular dysfunction. Tumors demonstrated histological features of schwannoma and express S100. Using this microsurgical technique, this xenograft rat model of VS develops tumors involving the cochleovestibular nerve, shifts in hearing thresholds, and vestibular dysfunction. This animal model can be used to investigate tumor-mediated hearing loss and perform preclinical drug studies for NF2.

Vestibular (dys)function in children with sensorineural hearing loss: a systematic review.

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Verbecque, Evi; Marijnissen, Tessa; De Belder, Niels; Van Rompaey, Vincent; Boudewyns, An; Van de Heyning, Paul; Vereeck, Luc; Hallemans, Ann

2017-06-01

The objective of this study is to provide an overview of the prevalence of vestibular dysfunction in children with SNHL classified according to the applied test and its corresponding sensitivity and specificity. Data were gathered using a systematic search query including reference screening. Pubmed, Web of Science and Embase were searched. Strategy and reporting of this review was based on the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. Methodological quality was assessed with the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. All studies, regardless the applied vestibular test, showed that vestibular function differs significantly between children with hearing loss and normal hearing (p 30).

Bilateral bone conduction devices: improved hearing ability in children with bilateral conductive hearing loss.

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Dun, Catharina A J; Agterberg, Martijn J H; Cremers, Cor W R J; Hol, Myrthe K S; Snik, Ad F M

2013-01-01

The aim of the study was to investigate whether children with bilateral conductive hearing loss benefit from their second device (i.e., the bilateral bone conduction device [BCD]). Speech recognition in noise was assessed in 10 children fitted with bilateral BCDs during childhood. Speech recognition was measured in 2 conditions with both BCDs active. Spatial resolution was tested with the Minimum Audible Angle test in the bilateral and monaural listening conditions. Children demonstrated an improvement in speech recognition when speech was presented from the front and noise was presented from the right-hand side as compared with both speech and noise being presented from the front. The minimum audible angle decreased from 57° in the best monaural condition to 13° in the bilateral condition. The audiological outcomes demonstrate the advantage of bilateral BCD fitting in children with bilateral conductive hearing loss.

Vestibular evaluation in children with otitis media with effusion.

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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.

Sudden bilateral hearing loss after organophosphate inhalation

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Mehmet Akif Dundar

2016-12-01

Full Text Available Sudden bilateral hearing loss are seen rarely and the toxic substance exposure constitutes a small part of etiology. A Fifty-eight-year-old woman admitted to our clinic with sudden bilateral hearing loss shortly after chlorpyrifos-ethyl exposure. Otolaryngologic examination findings were normal. The patient had 40 dB sensorineural hearing loss (SNHL on the right ear and 48 dB SNHL on the left ear. Additional diagnostic tests were normal. The conventional treatment for sudden hearing loss was performed. On the second week following organophosphate (OP exposure the patient's hearing loss almost completely resolved. OP's are heavily used in agriculture and should be taken into consideration as an etiologic factor in sudden hearing loss. Keywords: Organophosphates, Hearing loss, Sudden

Dissociable cerebellar activity during spatial navigation and visual memory in bilateral vestibular failure.

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Jandl, N M; Sprenger, A; Wojak, J F; Göttlich, M; Münte, T F; Krämer, U M; Helmchen, C

2015-10-01

Spatial orientation and navigation depends on information from the vestibular system. Previous work suggested impaired spatial navigation in patients with bilateral vestibular failure (BVF). The aim of this study was to investigate event-related brain activity by functional magnetic resonance imaging (fMRI) during spatial navigation and visual memory tasks in BVF patients. Twenty-three BVF patients and healthy age- and gender matched control subjects performed learning sessions of spatial navigation by watching short films taking them through various streets from a driver's perspective along a route to the Cathedral of Cologne using virtual reality videos (adopted and modified from Google Earth). In the scanner, participants were asked to respond to questions testing for visual memory or spatial navigation while they viewed short video clips. From a similar but not identical perspective depicted video frames of routes were displayed which they had previously seen or which were completely novel to them. Compared with controls, posterior cerebellar activity in BVF patients was higher during spatial navigation than during visual memory tasks, in the absence of performance differences. This cerebellar activity correlated with disease duration. Cerebellar activity during spatial navigation in BVF patients may reflect increased non-vestibular efforts to counteract the development of spatial navigation deficits in BVF. Conceivably, cerebellar activity indicates a change in navigational strategy of BVF patients, i.e. from a more allocentric, landmark or place-based strategy (hippocampus) to a more sequence-based strategy. This interpretation would be in accord with recent evidence for a cerebellar role in sequence-based navigation. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Effectiveness of conventional versus virtual reality-based balance exercises in vestibular rehabilitation for unilateral peripheral vestibular loss: results of a randomized controlled trial.

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Meldrum, Dara; Herdman, Susan; Vance, Roisin; Murray, Deirdre; Malone, Kareena; Duffy, Douglas; Glennon, Aine; McConn-Walsh, Rory

2015-07-01

To compare the effectiveness of virtual reality-based balance exercises to conventional balance exercises during vestibular rehabilitation in patients with unilateral peripheral vestibular loss (UVL). Assessor-blind, randomized controlled trial. Two acute care university teaching hospitals. Patients with UVL (N=71) who had dizziness/vertigo, and gait and balance impairment. Patients with UVL were randomly assigned to receive 6 weeks of either conventional (n=36) or virtual reality-based (n=35) balance exercises during vestibular rehabilitation. The virtual reality-based group received an off-the-shelf virtual reality gaming system for home exercise, and the conventional group received a foam balance mat. Treatment comprised weekly visits to a physiotherapist and a daily home exercise program. The primary outcome was self-preferred gait speed. Secondary outcomes included other gait parameters and tasks, Sensory Organization Test (SOT), dynamic visual acuity, Hospital Anxiety and Depression Scale, Vestibular Rehabilitation Benefits Questionnaire, and Activities Balance Confidence Questionnaire. The subjective experience of vestibular rehabilitation was measured with a questionnaire. Both groups improved, but there were no significant differences in gait speed between the groups postintervention (mean difference, -.03m/s; 95% confidence interval [CI], -.09 to .02m/s). There were also no significant differences between the groups in SOT scores (mean difference, .82%; 95% CI, -5.00% to 6.63%) or on any of the other secondary outcomes (P>.05). In both groups, adherence to exercise was high (∼77%), but the virtual reality-based group reported significantly more enjoyment (P=.001), less difficulty with (P=.009) and less tiredness after (P=.03) balance exercises. At 6 months, there were no significant between-group differences in physical outcomes. Virtual reality-based balance exercises performed during vestibular rehabilitation were not superior to conventional balance

Ocular Motor Function in Patients with Bilateral Vestibular Weakness

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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.

Rotatory and collic vestibular evoked myogenic potential testing in normal-hearing and hearing-impaired children.

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Maes, Leen; De Kegel, Alexandra; Van Waelvelde, Hilde; Dhooge, Ingeborg

2014-01-01

Vertigo and imbalance are often underestimated in the pediatric population, due to limited communication abilities, atypical symptoms, and relatively quick adaptation and compensation in children. Moreover, examination and interpretation of vestibular tests are very challenging, because of difficulties with cooperation and maintenance of alertness, and because of the sometimes nauseatic reactions. Therefore, it is of great importance for each vestibular laboratory to implement a child-friendly test protocol with age-appropriate normative data. Because of the often masked appearance of vestibular problems in young children, the vestibular organ should be routinely examined in high-risk pediatric groups, such as children with a hearing impairment. Purposes of the present study were (1) to determine age-appropriate normative data for two child-friendly vestibular laboratory techniques (rotatory and collic vestibular evoked myogenic potential [cVEMP] test) in a group of children without auditory or vestibular complaints, and (2) to examine vestibular function in a group of children presenting with bilateral hearing impairment. Forty-eight typically developing children (mean age 8 years 0 months; range: 4 years 1 month to 12 years 11 months) without any auditory or vestibular complaints as well as 39 children (mean age 7 years 8 months; range: 3 years 8 months to 12 years 10 months) with a bilateral sensorineural hearing loss were included in this study. All children underwent three sinusoidal rotations (0.01, 0.05, and 0.1 Hz at 50 degrees/s) and bilateral cVEMP testing. No significant age differences were found for the rotatory test, whereas a significant increase of N1 latency and a significant threshold decrease was noticeable for the cVEMP, resulting in age-appropriate normative data. Hearing-impaired children demonstrated significantly lower gain values at the 0.01 Hz rotation and a larger percentage of absent cVEMP responses compared with normal-hearing children

Dizziness and Imbalance in the Elderly: Age-related Decline in the Vestibular System

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Iwasaki, Shinichi; Yamasoba, Tatsuya

2015-01-01

Dizziness and imbalance are amongst the most common complaints in older people, and are a growing public health concern since they put older people at a significantly higher risk of falling. Although the causes of dizziness in older people are multifactorial, peripheral vestibular dysfunction is one of the most frequent causes. Benign paroxysmal positional vertigo is the most frequent form of vestibular dysfunction in the elderly, followed by Meniere’s disease. Every factor associated with the maintenance of postural stability deteriorates during aging. Age-related deterioration of peripheral vestibular function has been demonstrated through quantitative measurements of the vestibulo-ocular reflex with rotational testing and of the vestibulo-collic reflex with testing of vestibular evoked myogenic potentials. Age-related decline of vestibular function has been shown to correlate with the age-related decrease in the number of vestibular hair cells and neurons. The mechanism of age-related cellular loss in the vestibular endorgan is unclear, but it is thought that genetic predisposition and cumulative effect of oxidative stress may both play an important role. Since the causes of dizziness in older people are multi-factorial, management of this disease should be customized according to the etiologies of each individual. Vestibular rehabilitation is found to be effective in treating both unilateral and bilateral vestibular dysfunction. Various prosthetic devices have also been developed to improve postural balance in older people. Although there have been no medical treatments improving age-related vestibular dysfunction, new medical treatments such as mitochondrial antioxidants or caloric restriction, which have been effective in preventing age-related hearing loss, should be ienvestigated in the future. PMID:25657851

Saccadic entropy of head impulses in acute unilateral vestibular loss.

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Hsieh, Li-Chun; Lin, Hung-Ching; Lee, Guo-She

2017-10-01

To evaluate the complexity of vestibular-ocular reflex (VOR) in patients with acute unilateral vestibular loss (AUVL) via entropy analysis of head impulses. Horizontal head impulse test (HIT) with high-velocity alternating directions was used to evaluate 12 participants with AUVL and 16 healthy volunteers. Wireless electro-oculography and electronic gyrometry were used to acquire eye positional signals and head velocity signals. The eye velocity signals were then obtained through differentiation, band-pass filtering. The approximate entropy of eye velocity to head velocity (R ApEn ) was used to evaluate chaos property. VOR gain, gain asymmetry ratio, and R ApEn asymmetry ratio were also used to compare the groups. For the lesion-side HIT of the patient group, the mean VOR gain was significantly lower and the mean R ApEn was significantly greater compared with both nonlesion-side HIT and healthy controls (p Entropy and gain analysis of HIT using wireless electro-oculography system could be used to detect the VOR dysfunctions of AUVL and may become effective methods for evaluating vestibular disorders. Copyright © 2017. Published by Elsevier B.V.

Evidence for a role of orexin/hypocretin system in vestibular lesion-induced locomotor abnormalities in rats

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Leilei Pan

2016-07-01

Full Text Available Vestibular damage can induce locomotor abnormalities in both animals and humans. Rodents with bilateral vestibular loss showed vestibular deficits syndrome such as circling, opisthotonus as well as locomotor and exploratory hyperactivity. Previous studies have investigated the changes in the dopamine system after vestibular loss, but the results are inconsistent and inconclusive. Numerous evidences indicate that the orexin system is implicated in central motor control. We hypothesized that orexin may be potentially involved in vestibular loss-induced motor disorders. In this study, we examined the effects of arsanilate- or 3, 3′-iminodipropionitrile (IDPN-induced vestibular lesion (AVL or IVL on the orexin-A (OXA labeling in rat hypothalamus using immunohistochemistry. The vestibular lesion-induced locomotor abnormalities were recorded and verified using a histamine H4 receptor antagonist JNJ7777120 (20 mg/kg, i.p.. The effects of the orexin receptor type 1 antagonist SB334867 (16 μg, i.c.v. on these behavior responses were also investigated. At 72 h post-AVL and IVL, animals exhibited vestibular deficit syndrome and locomotor hyperactivity in the home cages. These responses were significantly alleviated by JNJ7777120 which also eliminated AVL-induced increases in exploratory behavior in an open field. The numbers of OXA-labeled neurons in the hypothalamus were significantly increased in the AVL animals at 72 h post-AVL and in the IVL animals at 24, 48 and 72 h post-IVL. SB334867 significantly attenuated the vestibular deficit syndrome and locomotor hyperactivity at 72 h post-AVL and IVL. It also decreased exploratory behavior in the AVL animals. These results suggested that the alteration of OXA expression might contribute to locomotor abnormalities after acute vestibular lesion. The orexin receptors might be the potential therapeutic targets for vestibular disorders.

Velocity dependence of vestibular information for postural control on tilting surfaces

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Kluzik, JoAnn; Hlavacka, Frantisek

2016-01-01

Vestibular information is known to be important for postural stability on tilting surfaces, but the relative importance of vestibular information across a wide range of surface tilt velocities is less clear. We compared how tilt velocity influences postural orientation and stability in nine subjects with bilateral vestibular loss and nine age-matched, control subjects. Subjects stood on a force platform that tilted 6 deg, toes-up at eight velocities (0.25 to 32 deg/s), with and without vision. Results showed that visual information effectively compensated for lack of vestibular information at all tilt velocities. However, with eyes closed, subjects with vestibular loss were most unstable within a critical tilt velocity range of 2 to 8 deg/s. Subjects with vestibular deficiency lost their balance in more than 90% of trials during the 4 deg/s condition, but never fell during slower tilts (0.25–1 deg/s) and fell only very rarely during faster tilts (16–32 deg/s). At the critical velocity range in which falls occurred, the body center of mass stayed aligned with respect to the surface, onset of ankle dorsiflexion was delayed, and there was delayed or absent gastrocnemius inhibition, suggesting that subjects were attempting to actively align their upper bodies with respect to the moving surface instead of to gravity. Vestibular information may be critical for stability at velocities of 2 to 8 deg/s because postural sway above 2 deg/s may be too fast to elicit stabilizing responses through the graviceptive somatosensory system, and postural sway below 8 deg/s may be too slow for somatosensory-triggered responses or passive stabilization from trunk inertia. PMID:27486101

A new dynamic visual acuity test to assess peripheral vestibular function.

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Vital, Domenic; Hegemann, Stefan C A; Straumann, Dominik; Bergamin, Oliver; Bockisch, Christopher J; Angehrn, Dominik; Schmitt, Kai-Uwe; Probst, Rudolf

2010-07-01

To evaluate a novel test for dynamic visual acuity (DVA) that uses an adaptive algorithm for changing the size of Landolt rings presented during active or passive head impulses, and to compare the results with search-coil head impulse testing. Prospective study in healthy individuals and patients with peripheral vestibular deficits. Tertiary academic center. One hundred neuro-otologically healthy individuals (age range, 19-80 years) and 15 patients with bilateral (n = 5) or unilateral (n = 10) peripheral vestibular loss (age range, 27-72 years). Testing of static visual acuity (SVA), DVA during active and passive horizontal head rotations (optotype presentation at head velocities >100 degrees/s and >150 degrees/s), and quantitative horizontal head impulse testing with scleral search coils. Difference between SVA and DVA, that is, visual acuity loss (VA loss), gain of the high-acceleration vestibulo-ocular reflex. Passive head impulses and higher velocities were more effective than active impulses and lower velocities. Using passive head impulses and velocities higher than 150 degrees/s, the DVA test discriminated significantly (P test sensitivity was 100%, specificity was 94%, and accuracy was 95%, with search-coil head impulse testing used as a reference. In healthy individuals, VA loss increased significantly with age (P testing with Landolt rings that are adaptively changed in size enables detection of peripheral vestibular dysfunction in a fast and simple way.

Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

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Rasmussen, Rune, E-mail: rune333@gmail.com [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Claesson, Magnus [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark); Stangerup, Sven-Eric [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Roed, Henrik [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Christensen, Ib Jarle [Finsen Laboratory, Rigshospitalet, Copenhagen (Denmark); Caye-Thomasen, Per [Ear, Nose, and Throat Department, Rigshospitalet, Copenhagen (Denmark); Juhler, Marianne [Department of Neurosurgery, Rigshospitalet, Copenhagen (Denmark)

2012-08-01

Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a 'wait-and-scan' group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dose to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.

Fractionated Stereotactic Radiotherapy of Vestibular Schwannomas Accelerates Hearing Loss

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Rasmussen, Rune; Claesson, Magnus; Stangerup, Sven-Eric; Roed, Henrik; Christensen, Ib Jarle; Cayé-Thomasen, Per; Juhler, Marianne

2012-01-01

Objective: To evaluate long-term tumor control and hearing preservation rates in patients with vestibular schwannoma treated with fractionated stereotactic radiotherapy (FSRT), comparing hearing preservation rates to an untreated control group. The relationship between radiation dose to the cochlea and hearing preservation was also investigated. Methods and Materials: Forty-two patients receiving FSRT between 1997 and 2008 with a minimum follow-up of 2 years were included. All patients received 54 Gy in 27-30 fractions during 5.5-6.0 weeks. Clinical and audiometry data were collected prospectively. From a “wait-and-scan” group, 409 patients were selected as control subjects, matched by initial audiometric parameters. Radiation dose to the cochlea was measured using the original treatment plan and then related to changes in acoustic parameters. Results: Actuarial 2-, 4-, and 10-year tumor control rates were 100%, 91.5%, and 85.0%, respectively. Twenty-one patients had serviceable hearing before FSRT, 8 of whom (38%) retained serviceable hearing at 2 years after FSRT. No patients retained serviceable hearing after 10 years. At 2 years, hearing preservation rates in the control group were 1.8 times higher compared with the group receiving FSRT (P=.007). Radiation dose to the cochlea was significantly correlated to deterioration of the speech reception threshold (P=.03) but not to discrimination loss. Conclusion: FSRT accelerates the naturally occurring hearing loss in patients with vestibular schwannoma. Our findings, using fractionation of radiotherapy, parallel results using single-dose radiation. The radiation dose to the cochlea is correlated to hearing loss measured as the speech reception threshold.

Common Vestibular Disorders

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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

Atypical Manifestation of Vestibular Schwannoma

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Webster, Guilherme

2013-09-01

Full Text Available Introduction: Vestibular schwannoma (also known as acoustic neuroma is a benign tumor whose cells are derived from Schwann sheaths, which commonly occurs from the vestibular portion of the eighth cranial nerve. Furthermore, vestibular schwannomas account for ∼8% of intracranial tumors in adults and 80 to 90% of tumors of the cerebellopontine angle. Its symptoms are varied, but what stands out most is a unilateral sensorineural hearing loss, with a low index of speech recognition. Objective: Describe an atypical manifestation of vestibular schwannoma. Case Report: The 46-year-old woman had vertigo and binaural hearing loss and fullness, with ear, nose, and throat examination suggestive of cochlear injury. After 6 months, the patient developed worsening of symptoms and onset of right unilateral tinnitus. In further exams the signs of cochlear damage remained, except for the vestibular test (hyporeflexia. Magnetic resonance imaging showed an expansive lesion in the right cerebellopontine angle. Discussion: This report warns about the atypical manifestations of vestibular schwannoma, which must always be remembered in investigating and diagnosing hearing loss.

Hierarchical Cluster Analysis of Semicircular Canal and Otolith Deficits in Bilateral Vestibulopathy

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Alexander A. Tarnutzer

2018-04-01

Full Text Available BackgroundGait imbalance and oscillopsia are frequent complaints of bilateral vestibular loss (BLV. Video-head-impulse testing (vHIT of all six semicircular canals (SCCs has demonstrated varying involvement of the different canals. Sparing of anterior-canal function has been linked to aminoglycoside-related vestibulopathy and Menière’s disease. We hypothesized that utricular and saccular impairment [assessed by vestibular-evoked myogenic potentials (VEMPs] may be disease-specific also, possibly facilitating the differential diagnosis.MethodsWe searched our vHIT database (n = 3,271 for patients with bilaterally impaired SCC function who also received ocular VEMPs (oVEMPs and cervical VEMPs (cVEMPs and identified 101 patients. oVEMP/cVEMP latencies above the 95th percentile and peak-to-peak amplitudes below the 5th percentile of normal were considered abnormal. Frequency of impairment of vestibular end organs (horizontal/anterior/posterior SCC, utriculus/sacculus was analyzed with hierarchical cluster analysis and correlated with the underlying etiology.ResultsRates of utricular and saccular loss of function were similar (87.1 vs. 78.2%, p = 0.136, Fisher’s exact test. oVEMP abnormalities were found more frequent in aminoglycoside-related bilateral vestibular loss (BVL compared with Menière’s disease (91.7 vs. 54.6%, p = 0.039. Hierarchical cluster analysis indicated distinct patterns of vestibular end-organ impairment, showing that the results for the same end-organs on both sides are more similar than to other end-organs. Relative sparing of anterior-canal function was reflected in late merging with the other end-organs, emphasizing their distinct state. An anatomically corresponding pattern of SCC/otolith hypofunction was present in 60.4% (oVEMPs vs. horizontal SCCs, 34.7% (oVEMPs vs. anterior SCCs, and 48.5% (cVEMPs vs. posterior SCCs of cases. Average (±1 SD number of damaged sensors was 6.8 ± 2.2 out of 10

A vestibular phenotype for Waardenburg syndrome?

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Black, F. O.; Pesznecker, S. C.; Allen, K.; Gianna, C.

2001-01-01

OBJECTIVE: To investigate vestibular abnormalities in subjects with Waardenburg syndrome. STUDY DESIGN: Retrospective record review. SETTING: Tertiary referral neurotology clinic. SUBJECTS: Twenty-two adult white subjects with clinical diagnosis of Waardenburg syndrome (10 type I and 12 type II). INTERVENTIONS: Evaluation for Waardenburg phenotype, history of vestibular and auditory symptoms, tests of vestibular and auditory function. MAIN OUTCOME MEASURES: Results of phenotyping, results of vestibular and auditory symptom review (history), results of vestibular and auditory function testing. RESULTS: Seventeen subjects were women, and 5 were men. Their ages ranged from 21 to 58 years (mean, 38 years). Sixteen of the 22 subjects sought treatment for vertigo, dizziness, or imbalance. For subjects with vestibular symptoms, the results of vestibuloocular tests (calorics, vestibular autorotation, and/or pseudorandom rotation) were abnormal in 77%, and the results of vestibulospinal function tests (computerized dynamic posturography, EquiTest) were abnormal in 57%, but there were no specific patterns of abnormality. Six had objective sensorineural hearing loss. Thirteen had an elevated summating/action potential (>0.40) on electrocochleography. All subjects except those with severe hearing loss (n = 3) had normal auditory brainstem response results. CONCLUSION: Patients with Waardenburg syndrome may experience primarily vestibular symptoms without hearing loss. Electrocochleography and vestibular function tests appear to be the most sensitive measures of otologic abnormalities in such patients.

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

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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.

Gaze stabilization in chronic vestibular-loss and in cerebellar ataxia: interactions of feedforward and sensory feedback mechanisms.

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Sağlam, M; Lehnen, N

2014-01-01

During gaze shifts, humans can use visual, vestibular, and proprioceptive feedback, as well as feedforward mechanisms, for stabilization against active and passive head movements. The contributions of feedforward and sensory feedback control, and the role of the cerebellum, are still under debate. To quantify these contributions, we increased the head moment of inertia in three groups (ten healthy, five chronic vestibular-loss and nine cerebellar-ataxia patients) while they performed large gaze shifts to flashed targets in darkness. This induces undesired head oscillations. Consequently, both active (desired) and passive (undesired) head movements had to be compensated for to stabilize gaze. All groups compensated for active and passive head movements, vestibular-loss patients less than the other groups (P feedforward mechanisms substantially contribute to gaze stabilization. Proprioception alone is not sufficient (gain 0.2). Stabilization against active and passive head movements was not impaired in our cerebellar ataxia patients.

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.

Central Lesions With Selective Semicircular Canal Involvement Mimicking Bilateral Vestibulopathy

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Luke Chen

2018-04-01

Full Text Available Bilateral vestibulopathy (BVP, which is due to peripheral lesions, may selectively involve certain semicircular canal (SCC. Recent eye movement recordings with search coil and video head impulse test (HIT have provided insight in central lesions that can cause bilateral and selective SCC deficit mimicking BVP. Since neurological signs or ocular motor deficits maybe subtle or absent, it is critical to recognize central lesions correctly since there is prognostic and treatment implication. Acute floccular lesions cause bilateral horizontal SCC (HC impairment while leaving vertical SCC function unaffected. Vestibular nuclear lesions affect bilateral HC and posterior SCC (PC function, but anterior SCC (AC function is spared. When both eyes are recorded, medial longitudinal fasciculus lesions cause horizontal dysconjugacy in HC function and catch-up saccades, as well as selective deficiency of PC over AC function. Combined peripheral and central lesions may be difficult to distinguish from BVP. Anterior inferior cerebellar artery stroke causes two types of deficits: 1. ipsilateral pan-SCC deficits and contralateral HC deficit and 2. bilateral HC deficit with vertical SCC sparing. Metabolic disorders such as Wernicke encephalopathy characteristically involve HC but not AC or PC function. Gaucher disease causes uniform loss of all SCC function but with minimal horizontal catch-up saccades. Genetic cerebellar ataxias and cerebellar-ataxia neuropathy vestibular areflexia syndrome typically do not spare AC function. While video HIT does not replace the gold-standard, search coil HIT, clinicians are now able to rapidly and accurately identify specific pattern of SCC deficits, which can aid differentiation of central lesions from BVP.

Effectiveness of conventional versus virtual reality based vestibular rehabilitation in the treatment of dizziness, gait and balance impairment in adults with unilateral peripheral vestibular loss: a randomised controlled trial.

Science.gov (United States)

Meldrum, Dara; Herdman, Susan; Moloney, Roisin; Murray, Deirdre; Duffy, Douglas; Malone, Kareena; French, Helen; Hone, Stephen; Conroy, Ronan; McConn-Walsh, Rory

2012-03-26

Unilateral peripheral vestibular loss results in gait and balance impairment, dizziness and oscillopsia. Vestibular rehabilitation benefits patients but optimal treatment remains unknown. Virtual reality is an emerging tool in rehabilitation and provides opportunities to improve both outcomes and patient satisfaction with treatment. The Nintendo Wii Fit Plus® (NWFP) is a low cost virtual reality system that challenges balance and provides visual and auditory feedback. It may augment the motor learning that is required to improve balance and gait, but no trials to date have investigated efficacy. In a single (assessor) blind, two centre randomised controlled superiority trial, 80 patients with unilateral peripheral vestibular loss will be randomised to either conventional or virtual reality based (NWFP) vestibular rehabilitation for 6 weeks. The primary outcome measure is gait speed (measured with three dimensional gait analysis). Secondary outcomes include computerised posturography, dynamic visual acuity, and validated questionnaires on dizziness, confidence and anxiety/depression. Outcome will be assessed post treatment (8 weeks) and at 6 months. Advances in the gaming industry have allowed mass production of highly sophisticated low cost virtual reality systems that incorporate technology previously not accessible to most therapists and patients. Importantly, they are not confined to rehabilitation departments, can be used at home and provide an accurate record of adherence to exercise. The benefits of providing augmented feedback, increasing intensity of exercise and accurately measuring adherence may improve conventional vestibular rehabilitation but efficacy must first be demonstrated. Clinical trials.gov identifier: NCT01442623.

Evaluation of the Vestibular System and Etiology in Children with Unilateral Sensorineural Hearing Loss.

Science.gov (United States)

Birdane, Leman; İncesulu, Armağan; Özüdoğru, Erkan; Cingi, Cemal; Caklı, Hamdi; Gürbüz, Melek Kezban; Adapınar, Baki

2016-08-01

The aim of this study was to evaluate the vestibular system of children with unilateral sensorineural hearing loss (USNHL), investigate the etiological factors of USNHL and analyze whether a genetic predisposition exists. Thirty-three children aged less than 18 years with USNHL, who visited the ear, nose, and throat (ENT) department between January 2004 and December 2012, were included in this study. Cases with conductive hearing loss were excluded from the study. The patients were subjected to etiologic, genetic, and ophthalmologic evaluation; radiologic imaging; electronystagmography (ENG); and vestibular evoked myogenic potential (VEMP) tests. The control group, which included 25 healthy children (13 males and 12 females), had undergone audiological assessment and were subjected to ENG and VEMP tests. All of the patients had severe-to-profound hearing loss. Mumps immunoglobulin G was positive in 22 (66.7%) of 33 patients. The 35delG mutation was not found in any of the patients. All of the patients underwent temporal computed tomography (CT) and magnetic resonance imaging (MRI). Inner ear anomaly was present in 51.5% of the patients. Overall, 21 of 31 ENG patients had canal paresis in the affected ear. The VEMP response was absent on the affected side in three patients. The n23 latency average of the patient group was longer than that of the control group. Because USNHL causes irreversible problems in children, early diagnosis and auditory rehabilitation are very important. As USNHL is accompanied by inner ear anomaly, children with USNHL should undergo temporal bone CT and MRI. To evaluate the vestibular system, ENG and VEMP are non-invasive and diagnostic tests.

Effectiveness of conventional versus virtual reality based vestibular rehabilitation in the treatment of dizziness, gait and balance impairment in adults with unilateral peripheral vestibular loss: a randomised controlled trial

Directory of Open Access Journals (Sweden)

Dara Meldrum

2012-03-01

Full Text Available Abstract Background Unilateral peripheral vestibular loss results in gait and balance impairment, dizziness and oscillopsia. Vestibular rehabilitation benefits patients but optimal treatment remains unkown. Virtual reality is an emerging tool in rehabilitation and provides opportunities to improve both outcomes and patient satisfaction with treatment. The Nintendo Wii Fit Plus® (NWFP is a low cost virtual reality system that challenges balance and provides visual and auditory feedback. It may augment the motor learning that is required to improve balance and gait, but no trials to date have investigated efficacy. Methods/Design In a single (assessor blind, two centre randomised controlled superiority trial, 80 patients with unilateral peripheral vestibular loss will be randomised to either conventional or virtual reality based (NWFP vestibular rehabilitation for 6 weeks. The primary outcome measure is gait speed (measured with three dimensional gait analysis. Secondary outcomes include computerised posturography, dynamic visual acuity, and validated questionnaires on dizziness, confidence and anxiety/depression. Outcome will be assessed post treatment (8 weeks and at 6 months. Discussion Advances in the gaming industry have allowed mass production of highly sophisticated low cost virtual reality systems that incorporate technology previously not accessible to most therapists and patients. Importantly, they are not confined to rehabilitation departments, can be used at home and provide an accurate record of adherence to exercise. The benefits of providing augmented feedback, increasing intensity of exercise and accurately measuring adherence may improve conventional vestibular rehabilitation but efficacy must first be demonstrated. Trial registration Clinical trials.gov identifier: NCT01442623

Directional plasticity rapidly improves 3D vestibulo-ocular reflex alignment in monkeys using a multichannel vestibular prosthesis.

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Dai, Chenkai; Fridman, Gene Y; Chiang, Bryce; Rahman, Mehdi A; Ahn, Joong Ho; Davidovics, Natan S; Della Santina, Charles C

2013-12-01

Bilateral loss of vestibular sensation can be disabling. We have shown that a multichannel vestibular prosthesis (MVP) can partly restore vestibular sensation as evidenced by improvements in the 3-dimensional angular vestibulo-ocular reflex (3D VOR). However, a key challenge is to minimize misalignment between the axes of eye and head rotation, which is apparently caused by current spread beyond each electrode's targeted nerve branch. We recently reported that rodents wearing a MVP markedly improve 3D VOR alignment during the first week after MVP activation, probably through the same central nervous system adaptive mechanisms that mediate cross-axis adaptation over time in normal individuals wearing prisms that cause visual scene movement about an axis different than the axis of head rotation. We hypothesized that rhesus monkeys would exhibit similar improvements with continuous prosthetic stimulation over time. We created bilateral vestibular deficiency in four rhesus monkeys via intratympanic injection of gentamicin. A MVP was mounted to the cranium, and eye movements in response to whole-body passive rotation in darkness were measured repeatedly over 1 week of continuous head motion-modulated prosthetic electrical stimulation. 3D VOR responses to whole-body rotations about each semicircular canal axis were measured on days 1, 3, and 7 of chronic stimulation. Horizontal VOR gain during 1 Hz, 50 °/s peak whole-body rotations before the prosthesis was turned on was prosthetic stimulation under normal diurnal lighting. Similar improvements were noted for all animals, all three axes of rotation tested, for all sinusoidal frequencies tested (0.05-5 Hz), and for high-acceleration transient rotations. VOR asymmetry changes did not reach statistical significance, although they did trend toward slight improvement over time. Prior studies had already shown that directional plasticity reduces misalignment when a subject with normal labyrinths views abnormal visual scene

MR imaging features and clinical value of vestibular aqueduct and endolymphatic sac in patients with large vestibular aqueduct syndrome

International Nuclear Information System (INIS)

Fang Zheming; Lou Xin; Lan Lan; Wang Hui; Wang Qiuju; Wu Nanzhou; Zhang Xiaojing

2012-01-01

Objective: To investigate MR imaging features of endolymphatic sac and vestibular aqueduct in patients with large vestibular aqueduct syndrome (LVAS) and its correlation with hearing loss. Methods: MR imaging findings of LVAS were analyzed in 31 cases (62 ears) retrospectively. MR imaging features were grouped into 4 types. In the first type, the signals of endolymphatic and vestibular aqueduct were hypointense without any hyperintense area. In the second type, the signals of endolymphatic sac and vestibular were hyperintense which were confined within vestibular fissure. In the third type, the area from vestibular aqueduct backward out of the edge of the petrous bone was hyperintense, but its lower boundary was above posterior semicircular. In the fourth type the area which was hyperintense was below the posterior semicircular. To avoid errors in visual inspection, the hyperintense and hypointense area of endolymphatic and the signal intensity of vestibular aqueduct and cerebrospinal fluid (CSF) were measured. The differences of signal intensity among the vestibular endolymphatic sac between the high-signal areas and low signal areas were compared with paired t-test. The correlation of the endolymphatic sac MRI classification and degree of hearing loss was analyzed by corrected Chi-square test and Spearman correlation analysis. Result: Ten ears belonged to type Ⅰ (moderate hearing loss in 1 ear,severe in 4 ears,profound in 5 ears), 17 ears belonged to type Ⅱ (moderate hearing loss in 1 ear; severe in 5 ears,profound in 11 ears), 23 ears to type Ⅲ (moderate hearing loss in 3 ear, severe in 5 ears, profound in 15 ears) and 12 ears belonged to Ⅳ (mild hearing loss in 1 ear, moderate in 1 ear, severe 3 ear, profound in 7 ears). The boundary between hyperintense and hypointense area was clear, and the signal intensity ratios was 2.02 ± 0.06. The signal ratios of hyperintense and hypointense area to vestibular and CSF were 0.95 ±0.12, 0.49 ±0.10, 0.99 ± 0

Recurrent Vestibular Migraine Vertigo Attacks Associated With the Development of Profound Bilateral Vestibulopathy: A Case Series.

Science.gov (United States)

Wester, Jacob L; Ishiyama, Akira; Ishiyama, Gail

2017-09-01

Bilateral vestibulopathy (BVP) is a debilitating condition characterized by gait ataxia, oscillopsia, and imbalance. Case series of patients with migraine-linked vertigo spells and profound BVP. PATIENT 1:: A 69-year-old man presented with a history of recurrent severe vertigo spells lasting up to 3 days in duration associated with prostrating migraine headaches starting at age 60. His symptoms were misdiagnosed as an anxiety syndrome. At age 68, electronystagmography (ENG) revealed bilaterally absent caloric responses and complete BVP. His hearing was normal. PATIENT 2:: A 51-year-old man presented with a history of "earthquake-like" vertigo, sharp head pain, and phonophobia. These episodes occurred a handful of times over a 7-year period. Previous ENG testing at age 43 was normal. However, his ENG at age 48 revealed complete BVP. He was started on acetazolamide and noted improved balance, although subsequent ENG was unchanged. PATIENT 3:: A 49-year-old woman presented with a history of recurrent migraines with visual aura associated with vertigo lasting 1 hour. ENG at age 50 revealed complete BVP. Subjectively, she noted improved balance with acetazolamide and subsequent ENG demonstrated mild improvement. PATIENT 4:: A 43-year-old man presented with a 5-year history of optical migraines and recurrent vertigo spells, lasting 30 seconds, which was misdiagnosed as positional vertigo. He additionally had a 10-year history of oscillopsia. ENG at age 61 revealed complete BVP. In these cases, vestibular migraine was linked to recurrent vertigo spells that eventually led to complete bilateral vestibulopathy.

Vestibular Loss in Older Adults Is Associated with Impaired Spatial Navigation: Data from the Triangle Completion Task

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Yanjun Xie

2017-04-01

Full Text Available BackgroundVestibular inputs have been shown to play a critical role in spatial navigation. In this study, we sought to evaluate whether vestibular loss due to aging contributes to impaired spatial navigation as measured by the triangle completion task (TCT.Materials and methodsWe recruited three types of participants: young controls <55 years of age, older controls ≥55 years of age, and older patients from a Neurotology Clinic with evidence of vestibular physiologic impairment but who did not have any known vestibular disorder. We performed the cervical vestibular-evoked myogenic potential to evaluate saccular function and video head impulse testing to quantify horizontal semicircular canal vestibulo-ocular reflex gain. To assess spatial navigation ability, we administered the TCT, in which participants were conveyed along two segments of a pre-drawn triangular path and instructed to complete the final segment independently. We measured the angle (degrees and distance (centimeters of deviation from the correct trajectory. We evaluated the influence of vestibular inputs on TCT performance.ResultsForty-eight adults participated in the study (mean age: 62.0 years; 52.1% females, including 9 young controls, 15 older controls, and 24 clinic patients. Clinic patients had the greatest distance of deviation (67.7 cm, followed by older controls (45.4 cm, then young controls (27.8 cm; p < 0.01. Similarly, clinic patients had greater rotational angles (22.1° compared to older (13.3° and younger controls (12.4°; p < 0.01. Following multivariate linear regression adjusting for demographic variables, loss of otolith function was associated with an 18.2 cm increase in distance of deviation (95% CI: 15.2–47.4 and a 9.2° increase in rotational angle (95% CI: 3.0–15.5. Abnormal semicircular canal function was associated with a 26.0 cm increase in distance of deviation (95% CI: 0.2–51.8 and a 10.8° increase in rotational angle

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

Science.gov (United States)

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.

Are Covert Saccade Functionally Relevant in Vestibular Hypofunction?

Science.gov (United States)

Hermann, R; Pelisson, D; Dumas, O; Urquizar, Ch; Truy, E; Tilikete, C

2018-06-01

The vestibulo-ocular reflex maintains gaze stabilization during angular or linear head accelerations, allowing adequate dynamic visual acuity. In case of bilateral vestibular hypofunction, patients use saccades to compensate for the reduced vestibulo-ocular reflex function, with covert saccades occurring even during the head displacement. In this study, we questioned whether covert saccades help maintain dynamic visual acuity, and evaluated which characteristic of these saccades are the most relevant to improve visual function. We prospectively included 18 patients with chronic bilateral vestibular hypofunction. Subjects underwent evaluation of dynamic visual acuity in the horizontal plane as well as video recording of their head and eye positions during horizontal head impulse tests in both directions (36 ears tested). Frequency, latency, consistency of covert saccade initiation, and gain of covert saccades as well as residual vestibulo-ocular reflex gain were calculated. We found no correlation between residual vestibulo-ocular reflex gain and dynamic visual acuity. Dynamic visual acuity performance was however positively correlated with the frequency and gain of covert saccades and negatively correlated with covert saccade latency. There was no correlation between consistency of covert saccade initiation and dynamic visual acuity. Even though gaze stabilization in space during covert saccades might be of very short duration, these refixation saccades seem to improve vision in patients with bilateral vestibular hypofunction during angular head impulses. These findings emphasize the need for specific rehabilitation technics that favor the triggering of covert saccades. The physiological origin of covert saccades is discussed.

Hearing Screening and Diagnostic Evaluation of Children With Unilateral and Mild Bilateral Hearing Loss

OpenAIRE

Ross, Danielle S.; Holstrum, W. June; Gaffney, Marcus; Green, Denise; Oyler, Robert F.; Gravel, Judith S.

2008-01-01

More than 90% of newborns in the United States are now being screened for hearing loss. A large fraction of cases of unilateral hearing loss and mild bilateral hearing loss are not currently identified through newborn hearing screening. This is of concern because a preponderance of research has demonstrated that unilateral hearing loss and mild bilateral hearing loss can lead to developmental delays and educational problems for some children. To help address this probable underidentification ...

Occupational Noise Exposure, Bilateral High-Frequency Hearing Loss, and Blood Pressure.

Science.gov (United States)

Gan, Wen Qi; Mannino, David M

2017-11-13

The aim of this study was to investigate the relationships between occupational noise exposure and blood pressure using self-reported occupational exposure and bilateral high-frequency hearing loss. This study included 4548 participants aged 20 to 69 years from the National Health and Nutrition Examination Survey 1999 to 2004. On the basis of self-reported exposure status, participants were divided into the current, former, or never exposed groups. Bilateral high-frequency hearing loss was defined as the average high-frequency hearing threshold at least 25 dB in both ears. The currently exposed participants had slightly increased diastolic blood pressure compared with those never exposed. Among previously exposed participants, those with bilateral high-frequency hearing loss had increased systolic blood pressure, heart rate, and the prevalence of hypertension compared with those with normal high-frequency hearing. Although there were some significant results, the evidence was not consistent to support the associations between occupational noise exposure and blood pressure.

Acute otitis media associated bilateral sudden hearing loss: case report and literature review.

Science.gov (United States)

Smith, A; Gutteridge, I; Elliott, D; Cronin, M

2017-07-01

Sudden sensorineural hearing loss is a rare otological condition with potential for dire outcomes including permanent hearing loss. Although the majority of cases are deemed idiopathic, bilateral sudden sensorineural hearing loss represents a rare subset typically related to systemic conditions, with higher morbidity and mortality. A controversial association with acute otitis media has been reported, with few bilateral cases published in the literature. A very rare case of bilateral sudden sensorineural hearing loss associated with acute otitis media is described, with a review of the literature. The limited evidence available suggests that acute otitis media with tinnitus and/or bacterial pathology may have an increased risk of sudden sensorineural hearing loss, which is consistent with the case described. Although there is no sufficiently powered published evidence to provide definitive treatment guidelines, the literature reviewed suggests that early myringotomy and antibiotics may greatly improve treatment outcomes.

Development of a multichannel vestibular prosthesis prototype by modification of a commercially available cochlear implant.

Science.gov (United States)

Valentin, Nicolas S; Hageman, Kristin N; Dai, Chenkai; Della Santina, Charles C; Fridman, Gene Y

2013-09-01

No adequate treatment exists for individuals who remain disabled by bilateral loss of vestibular (inner ear inertial) sensation despite rehabilitation. We have restored vestibular reflexes using lab-built multichannel vestibular prostheses (MVPs) in animals, but translation to clinical practice may be best accomplished by modification of a commercially available cochlear implant (CI). In this interim report, we describe preliminary efforts toward that goal. We developed software and circuitry to sense head rotation and drive a CI's implanted stimulator (IS) to deliver up to 1 K pulses/s via nine electrodes implanted near vestibular nerve branches. Studies in two rhesus monkeys using the modified CI revealed in vivo performance similar to our existing dedicated MVPs. A key focus of our study was the head-worn unit (HWU), which magnetically couples across the scalp to the IS. The HWU must remain securely fixed to the skull to faithfully sense head motion and maintain continuous stimulation. We measured normal and shear force thresholds at which HWU-IS decoupling occurred as a function of scalp thickness and calculated pressure exerted on the scalp. The HWU remained attached for human scalp thicknesses from 3-7.8 mm for forces experienced during routine daily activities, while pressure on the scalp remained below capillary perfusion pressure.

Augmented asymmetrical visual field dependence in asymptomatic diabetics: evidence of subclinical asymmetrical bilateral vestibular dysfunction.

Science.gov (United States)

Razzak, Rima Abdul; Bagust, Jeffery; Docherty, Sharon; Hussein, Wiam; Al-Otaibi, Abdullah

2015-01-01

Diabetes negatively affects the vestibular system in many ways, with vestibular dysfunction (VD), a co-morbidity with a high prevalence in diabetics. The ability to perceive subjective visual vertical (SVV), as a sign of vestibular dysfunction, and visual field dependence was measured using a computerized rod and frame test (CRAF). Alignment errors recorded from 47 asymptomatic Type II diabetics (no vertigo or falls, without peripheral neuropathy or retinopathy) were compared to 29 healthy age matched (46-69years) controls. Visual field dependence was significantly larger and more asymmetrical in the diabetics than controls. In the absence of any visual references, or when a vertical reference frame was provided, SVV perception was accurate in both groups, with no significant difference between the controls and diabetics. During tilted frame presentations, the proportion of subjects with either SVV deviations, or an asymmetry index, larger than an upper limit derived from the control data was significantly greater in diabetics than controls. These results suggest that the decreased ability to resolve visuo-vestibular conflict in asymptomatic diabetic patients (free of retinopathy and peripheral neuropathy) compared to controls may be related to diabetic complications affecting vestibular structures and thus causing a decompensation of subclinical vestibular asymmetries. Copyright © 2015 Elsevier Inc. All rights reserved.

Inner ear malformations in siblings presenting with vestibular ...

African Journals Online (AJOL)

Although the association between inner ear abnormalities and progressive sensorineural hearing loss is well known, vestibular signs or loss of vestibular function in these ... We provide a brief overview of the latest classification of these inner ear defects as well as a review of the literature pertaining to children with inner ear ...

Exposure to loud noise, bilateral high-frequency hearing loss and coronary heart disease.

Science.gov (United States)

Gan, Wen Qi; Moline, Jacqueline; Kim, Hyun; Mannino, David M

2016-01-01

Bilateral high-frequency hearing loss is an indicator for chronic exposure to loud noise. This study aimed to examine the association between bilateral high-frequency hearing loss and the presence of coronary heart disease (CHD). This study included 5223 participants aged 20-69 years who participated in the audiometry examination of the National Health and Nutrition Examination Survey 1999-2004. Bilateral high-frequency hearing loss was defined as the average high-frequency (3, 4 and 6 kHz) hearing threshold ≥25 dB in both ears. CHD was defined as self-reported diagnoses by doctors or other health professionals. Compared with those with normal high-frequency hearing, participants with bilateral high-frequency hearing loss were more likely to have CHD (OR 1.91; 95% CI 1.28 to 2.85) after adjustment for various covariates. This association was particularly strong for currently employed workers who were exposed to loud occupational noise (OR 4.23; 95% CI 1.32 to 13.55). For this subgroup, there was no significant association of CHD with unilateral high-frequency hearing loss, and unilateral or bilateral low-frequency hearing loss. Furthermore, there was no significant association of CHD with any types of hearing loss for participants who were not exposed to loud noise. Stratified analyses for participants exposed to loud noise showed that the observed association was particularly strong for those who were less than 50 years of age, less educated and current smokers. On the basis of an objective indicator for personal chronic exposure to loud noise, this study confirmed that exposure to loud occupational noise is associated with the presence of CHD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Ocular vestibular evoked myogenic potential elicited from binaural air-conducted stimulations: clinical feasibility in patients with peripheral vestibular dysfunction.

Science.gov (United States)

Iwasaki, Shinichi; Egami, Naoya; Inoue, Aki; Kinoshita, Makoto; Fujimoto, Chisato; Murofushi, Toshihisa; Yamasoba, Tatsuya

2013-07-01

Ocular vestibular evoked myogenic potentials (oVEMPs) to binaural air-conducted stimulation (ACS) may provide a convenient way of assessing the crossed vestibulo-ocular reflex in patients with vestibular dysfunction as well as in healthy subjects. To investigate the clinical feasibility of using oVEMPs in response to binaural ACS to assess normal subjects and patients with vestibular dysfunction. The study investigated 24 normal subjects (14 men and 10 women, aged from 23 to 60 years) and 14 patients with unilateral peripheral vestibular dysfunction. Each subject underwent oVEMP testing in response to monaural ACS and binaural ACS (500 Hz tone burst, 135 dBSPL). In normal subjects, bilateral oVEMPs were elicited in 75% of subjects in response to monaural ACS and in 91% in response to binaural ACS. Asymmetry ratios (ARs) of the responses to binaural ACS were significantly smaller than those of the responses to monaural ACS (p binaural ACS. Approximately 30% of patients showed reduced ARs to binaural ACS relative to monaural ACS, primarily due to contamination by uncrossed responses elicited in healthy ears.

Children with Mild Bilateral and Unilateral Hearing Loss: Parents' Reflections on Experiences and Outcomes

Science.gov (United States)

Fitzpatrick, Elizabeth; Grandpierre, Viviane; Durieux-Smith, Andrée; Gaboury, Isabelle; Coyle, Doug; Na, Eunjung; Sallam, Nusaiba

2016-01-01

Children with mild bilateral and unilateral hearing loss are now commonly identified early through newborn hearing screening initiatives. There remains considerable uncertainty about how to support parents and about which services to provide for children with mild bilateral and unilateral hearing loss. The goal of this study was to learn about…

Pesquisa da função vestibular em crianças com queixa de dificuldades escolares Vestibular function in children underperforming at school

Directory of Open Access Journals (Sweden)

Eloisa Sartori Franco

2008-12-01

Full Text Available O aprendizado é um processo complexo, dinâmico, estruturado a partir de um ato motor e perceptivo, que, elaborado corticalmente, dá origem à cognição. O equilíbrio é função neurológica importante para a manutenção de posturas adequadas, imprescindíveis no ato de aprender, indicativo de maturidade neurológica. OBJETIVO: Estudar a função vestibular em crianças com dificuldades escolares. ESTUDO DE CASO: Estudo clínico com coorte transversal. MATERIAL E MÉTODO: Foram estudadas 88 crianças entre 7 e 12 anos, que freqüentavam escolas públicas da cidade de Piracicaba durante os anos de 2004 e 2006. Os procedimentos utilizados foram: a anamnese; exame otorrinolaringológico; exame audiológico e avaliação vestibular. RESULTADOS: Das crianças avaliadas, 51,0% não relataram dificuldades escolares e 49,0% referiram ter dificuldades escolares. Encontramos 73,3% de exame vestibular normal nas crianças sem dificuldades escolares e 32,6% de normalidade nas crianças com dificuldades escolares. Encontramos alterações vestibulares de origem periférica irritativa tanto unilateral como bilateral, perfazendo um total de 67,4% para as crianças com dificuldades escolares e um total de 26,7% para crianças sem dificuldades escolares. CONCLUSÃO: Todas as alterações vestibulares encontradas foram de origem periférica irritativa. Os dados revelaram uma relação estatisticamente significante nas crianças com dificuldades escolares.Learning is a complex, dynamic process, structured from motor and perception skills which, when cortically processed, give birth to cognition. Balance is a fundamental neurological function that helps us maintain proper postures, an essential factor in learning and a sign or neurologic maturity. AIM: this paper aims to study vestibular function in children underperforming at school. STUDY DESIGN: this is a cross-sectional study. MATERIALS AND METHOD: eighty-eight children with ages ranging between 7 and 12

Gd enhanced MRI in sensorineural hearing loss

International Nuclear Information System (INIS)

Takenaka, Mika; Tono, Tetsuya; Toyama, Katsuhiro; Kano, Kiyo; Morimitsu, Tamotsu

1996-01-01

The enhanced MRI hearing findings of the inner ear in 124 patients with sensorineural hearing loss were evaluated. MR images were obtained before and after the intravenous administration of gadolinium (0.1 mmol/kg). In three out of seventy-nine patients with unilateral healing loss, cochlear and/or the vestibular enhancement was noted on the symptomatic side. The positive cases included those with Ramsay-Hunt syndrome, mumps and so-called sudden deafness. Forty-five patients with bilateral hearing loss showed no enhancement within the inner ear. Although positive gadolinium enhancement of the inner ear may detect inflammatory lesions due to a viral infection, its incidence in sensorineural hearing loss, including cases of sudden deafness. seems to be extremely rare. (author)

An unusual cause of conductive hearing loss: bilateral complete meatal obstruction following otoplasty.

Science.gov (United States)

Toplu, Yuksel; Toplu, Sibel Altunisik; Sapmaz, Emrah; Deliktas, Hacim

2014-01-01

There are many causes of conductive hearing loss. Otoplasty is a commonly performed cosmetic surgery to correction for prominent ear. We discussed an unusual cause of conductive hearing loss, bilateral complete meatal obstruction following otoplasty, in this article. This complication was probably due to unsuitable placement of the Furnas sutures. In the literature, as a cause of conductive hearing loss, unilateral complete meatal obstruction has been described rarely, but bilateral complete obstruction has not been defined. Hearing loss recovered completely after revision surgery. Correct diagnosis, accurate preoperative or perioperative examination, choice of the proper technique and surgeon experience are essential for avoiding inadequate results or complications of otoplasty. The surgeon should be aware of the cartilage elasticity and suture techniques to avoid this complication.

Reduced systemic toxicity and preserved vestibular toxicity following co-treatment with nitriles and CYP2E1 inhibitors: a mouse model for hair cell loss.

Science.gov (United States)

Saldaña-Ruíz, Sandra; Boadas-Vaello, Pere; Sedó-Cabezón, Lara; Llorens, Jordi

2013-10-01

Several nitriles, including allylnitrile and cis-crotononitrile, have been shown to be ototoxic and cause hair cell degeneration in the auditory and vestibular sensory epithelia of mice. However, these nitriles can also be lethal due in large part to the microsomal metabolic release of cyanide, which is mostly dependent on the activity of the 2E1 isoform of the cytochrome P450 (CYP2E1). In this study, we co-administered mice with a nitrile and, to reduce their lethal effects, a selective CYP2E1 inhibitor: diallylsulfide (DAS) or trans-1,2-dichloroethylene (TDCE). Both in female 129S1/SvImJ (129S1) mice co-treated with DAS and cis-crotononitrile and in male RjOrl:Swiss/CD-1 (Swiss) mice co-treated with TDCE and allylnitrile, the nitrile caused a dose-dependent loss of vestibular function, as assessed by a specific behavioral test battery, and of hair cells, as assessed by hair bundle counts using scanning electron microscopy. In the experiments, the CYP2E1 inhibitors provided significant protection against the lethal effects of the nitriles and did not diminish the vestibular toxicity as assessed by behavioral effects in comparison to animals receiving no inhibitor. Additional experiments using a single dose of allylnitrile demonstrated that TDCE does not cause hair cell loss on its own and does not modify the vestibular toxicity of the nitrile in either male or female 129S1 mice. In all the experiments, high vestibular dysfunction scores in the behavioral test battery predicted extensive to complete loss of hair cells in the utricles. This provides a means of selecting animals for subsequent studies of vestibular hair cell regeneration or replacement.

Social Skills in Preschool Children with Unilateral and Mild Bilateral Hearing Loss

Science.gov (United States)

Laugen, Nina J.; Jacobsen, Karl H.; Rieffe, Carolien; Wichstrøm, Lars

2017-01-01

Hearing loss may represent a risk for developing social skills difficulties; however, little is known about the potential risk resulting from unilateral or mild bilateral hearing loss (UMHL). We compared the social skills of 14 children with UMHL and 21 children with moderate to severe hearing loss (MSHL) with those of 123 children with typical…

[From gene to disease; genetic causes of hearing loss and visual impairment sometimes accompanied by vestibular problems (Usher syndrome)

NARCIS (Netherlands)

Pennings, R.J.E.; Kremer, J.M.J.; Deutman, A.F.; Kimberling, W.J.; Cremers, C.W.R.J.

2002-01-01

Usher syndrome is an autosomal recessively inherited disease, characterised by sensorineural hearing loss, tapetoretinal degeneration and in some cases vestibular problems. Based on the clinical heterogeneity, the disease can be classified into three clinical types (I, II and III), which have their

Evaluation of the outcome of CT and MR imaging in pediatric patients with bilateral sensorineural hearing loss.

Science.gov (United States)

van Beeck Calkoen, E A; Merkus, P; Goverts, S T; van de Kamp, J M; Mulder, M F; Sanchez Aliaga, E; Hensen, E F

2018-05-01

To evaluate the clinically relevant abnormalities as visualized on CT and MR imaging in children with symmetric and asymmetric bilateral sensorineural hearing loss (SNHL), in relation to age and the severity of hearing loss. Retrospective cohort study. Tertiary referral otology and audiology center. From January 2006 until January 2016, a total of 207 children diagnosed with symmetric and asymmetric bilateral SNHL were included. They underwent CT and/or MR imaging for the evaluation of the etiology of their hearing loss. Radiologic abnormalities associated with SNHL. 302 scans were performed in 207 children (median age of 0.8 years old) with bilateral SNHL. The most frequently identified cause of bilateral SNHL was a malformation of the labyrinth. The combined diagnostic yield of CT and MR imaging was 32%. The diagnostic yield of MR (34%) was considerably higher than that of CT (20%). We found a higher rate of abnormalities in children with profound hearing loss (41%) compared to milder hearing loss (8-29%), and in asymmetric SNHL (52%) compared to symmetric SNHL (30%). Imaging is essential in the etiologic evaluation of children with bilateral SNHL. The highest diagnostic yield is found in children with bilateral asymmetric SNHL or profound SNHL. Based on our findings, MR is the primary imaging modality of choice in the etiological evaluation of children with bilateral SNHL because of its high diagnostic yield. Copyright © 2018. Published by Elsevier B.V.

Vestibular brain changes within 70 days of head down bed rest.

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; Seidler, Rachael

2018-03-12

Head-down-tilt bed rest (HDBR) is frequently utilized as a spaceflight analog research environment to study the effects of axial body unloading and fluid shifts that are associated with spaceflight in the absence of gravitational modifications. HDBR has been shown to result in balance changes, presumably due to sensory reweighting and adaptation processes. Here, we examined whether HDBR results in changes in the neural correlates of vestibular processing. Thirteen men participated in a 70-day HDBR intervention; we measured balance, functional mobility, and functional brain activity in response to vestibular stimulation at 7 time points before, during, and after HDBR. Vestibular stimulation was administered by means of skull taps, resulting in activation of the vestibular cortex and deactivation of the cerebellar, motor, and somatosensory cortices. Activation in the bilateral insular cortex, part of the vestibular network, gradually increased across the course of HDBR, suggesting an upregulation of vestibular inputs in response to the reduced somatosensory inputs experienced during bed rest. Furthermore, greater increase of activation in multiple frontal, parietal, and occipital regions in response to vestibular stimulation during HDBR was associated with greater decrements in balance and mobility from before to after HDBR, suggesting reduced neural efficiency. These findings shed light on neuroplastic changes occurring with conditions of altered sensory inputs, and reveal the potential for central vestibular-somatosensory convergence and reweighting with bed rest. © 2018 Wiley Periodicals, Inc.

Congenital cytomegalovirus (CMV) infection as a cause of permanent bilateral hearing loss: a quantitative assessment.

Science.gov (United States)

Grosse, Scott D; Ross, Danielle S; Dollard, Sheila C

2008-02-01

Congenital cytomegalovirus (CMV) infection is a cause of sensorineural hearing loss (SNHL) in children, but the magnitude of its contribution is uncertain. Quantifying the impact of congenital CMV infection requires an evidence-based assessment using a standard case definition of hearing loss. To determine the frequency of bilateral moderate to profound SNHL in children with congenital CMV infection and to estimate the CMV-attributable fraction of bilateral moderate to profound SNHL. A systematic review of studies of children with congenital CMV infection ascertained in an unbiased manner through universal newborn screening for CMV using viral culture in urine or saliva specimens in combination with a review of the literature on congenital CMV infection and hearing loss, including articles of all types. Approximately, 14% of children with congenital CMV infection develop SNHL of some type, and 3-5% develop bilateral moderate to profound SNHL. Among all children with bilateral moderate to profound SNHL, we estimate that 15-20% of cases are attributable to congenital CMV infection. Congenital CMV infection is one of the most important causes of hearing loss in young children, second only to genetic mutations, and is potentially preventable.

[Vestibular compensation studies]. [Vestibular Compensation and Morphological Studies

Science.gov (United States)

Perachio, Adrian A. (Principal Investigator)

1996-01-01

The following topics are reported: neurophysiological studies on MVN neurons during vestibular compensation; effects of spinal cord lesions on VNC neurons during compensation; a closed-loop vestibular compensation model for horizontally canal-related MVN neurons; spatiotemporal convergence in VNC neurons; contributions of irregularly firing vestibular afferents to linear and angular VOR's; application to flight studies; metabolic measures in vestibular neurons; immediate early gene expression following vestibular stimulation; morphological studies on primary afferents, central vestibular pathways, vestibular efferent projection to the vestibular end organs, and three-dimensional morphometry and imaging.

Vestibular morphology in the German Waltzing guinea pig.

Science.gov (United States)

Kawaguchi, Sachie; Hultcrantz, Malou; Jin, Zhe; Ulfendahl, Mats; Suzuki, Mamoru

2010-04-01

The German waltzing guinea pig is a special strain of animal with a recessively inherited inner ear defect, resulting in deafness and a severe vestibular dysfunction. The hearing loss in the cochlea of the German strain is a result of a collapse of the Reissner membrane and the absence of scala media. The vestibular organ has not yet been described. German waltzing guinea pigs (homozygote and heterozygote) of different ages ranging from embryologic age 25 days to adulthood were investigated. The living animals were tested with four different vestibular tests, and the fetuses were controlled according to breeding. The morphology of the vestibular parts (ampulla, saccule, and utricle) was observed by using the light and transmission electron microscopy. Collapse of the membranous labyrinth was found already at embryologic age 50 days and progressed over time. Vestibular dysfunction was noted already from birth. Vestibular atelectasis has been shown to have the same morphology as the reported vestibular dysfunction in the German waltzing guinea pig. Owing to this similarity, this animal can be a good model for vestibular research.

A common SLC26A4-linked haplotype underlying non-syndromic hearing loss with enlargement of the vestibular aqueduct

DEFF Research Database (Denmark)

Chattaraj, Parna; Munjal, Tina; Honda, Keiji

2017-01-01

BACKGROUND: Enlargement of the vestibular aqueduct (EVA) is the most common radiological abnormality in children with sensorineural hearing loss. Mutations in coding regions and splice sites of the SLC26A4 gene are often detected in Caucasians with EVA. Approximately one-fourth of patients with E...

Computed tomography findings in large vestibular aqueduct syndrome.

Science.gov (United States)

Ma, Xiufang; Yang, Ying; Xia, Ming; Li, Dumin; Xu, Anting

2009-07-01

Patients with large vestibular aqueduct syndrome (LVAS) have disturbed morphogenesis of bony labyrinth. Semicircular canal anomalies are common in LVAS. To describe the additional inner ear anomalies on CT imaging in pediatric patients with LVAS, and to investigate the lateral semicircular canal (LSCC) anomalies associated with LVAS by measurement of the LSCC bony island width. We retrospectively reviewed the digitally stored temporal bone CT imaging obtained for 23 patients with LVAS, additional inner ear anomalies were noted, and measurements of the LSCC bony island width were made on axial CT scans on the workstation. Measurements were compared to the normative data obtained from 20 patients without sensorineural hearing loss. Of the 23 patients (bilateral in 22 and unilateral in 1), additional inner ear malformations were identified in 21 cases presenting either singly or in combination. A small LSCC bony island (Mondini deformity was identified in 6 ears.

Modified Willet's appliance for bilateral loss of multiple deciduous molars: a case report.

Science.gov (United States)

Dhindsa, A; Pandit, I K

2008-09-01

No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a variety of problems. Thus, the conventional designs are required to be modified according to the needs of the patient. Therefore, this paper describes an entirely new design of the Willet's appliance in cases of bilateral loss of deciduous molars before the eruption of first permanent molar.

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

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...

Plasticity during vestibular compensation: the role of saccades

Directory of Open Access Journals (Sweden)

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.

[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.

Peripheral Vestibular System Disease in Vestibular Schwannomas

DEFF Research Database (Denmark)

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

2015-01-01

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...... are associated with distinctive disease of the peripheral vestibular tissue structures, suggesting anterograde degeneration and that dizziness in these patients may be caused by deficient peripheral vestibular nerve fibers, neurons, and end organs. In smaller tumors, a highly localized disease occurs, which...

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.

Speech perception, production and intelligibility in French-speaking children with profound hearing loss and early cochlear implantation after congenital cytomegalovirus infection.

Science.gov (United States)

Laccourreye, L; Ettienne, V; Prang, I; Couloigner, V; Garabedian, E-N; Loundon, N

2015-12-01

To analyze speech in children with profound hearing loss following congenital cytomegalovirus (cCMV) infection with cochlear implantation (CI) before the age of 3 years. In a cohort of 15 children with profound hearing loss, speech perception, production and intelligibility were assessed before and 3 years after CI; variables impacting results were explored. Post-CI, median word recognition was 74% on closed-list and 48% on open-list testing; 80% of children acquired speech production; and 60% were intelligible for all listeners or listeners attentive to lip-reading and/or aware of the child's hearing loss. Univariate analysis identified 3 variables (mean post-CI hearing threshold, bilateral vestibular areflexia, and brain abnormality on MRI) with significant negative impact on the development of speech perception, production and intelligibility. CI showed positive impact on hearing and speech in children with post-cCMV profound hearing loss. Our study demonstrated the key role of maximizing post-CI hearing gain. A few children had insufficient progress, especially in case of bilateral vestibular areflexia and/or brain abnormality on MRI. This led us to suggest that balance rehabilitation and speech therapy should be intensified in such cases. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Audiovestibular Function Deficits in Vestibular Schwannoma

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Constantin von Kirschbaum

2016-01-01

Full Text Available Introduction. Vestibular schwannomas (VS are benign tumours of the vestibular nerve and can lead to hearing loss, tinnitus, vertigo, facial palsy, and brainstem compression. Audiovestibular diagnostic tests are essential for detection and treatment planning. Methods. Medline was used to perform a systematic literature review with regard to how audiovestibular test parameters correlate with symptoms, tumour size, and tumour location. Results. The auditory brainstem response can be used to diagnose retrocochlear lesions caused by VS. Since hearing loss correlates poorly with tumour size, a retrocochlear lesion is probably not the only cause for hearing loss. Also cochlear mechanisms seem to play a role. This can be revealed by abnormal otoacoustic emissions, despite normal ABR and new MRI techniques which have demonstrated endolymphatic hydrops of the inner ear. Caloric and head impulse tests show frequency specific dynamics and vestibular evoked myogenic potentials may help to identify the location of the tumour regarding the involved nerve parts. Conclusion. In order to preserve audiovestibular function in VS, it is important to stop the growth of the tumour and to avoid degenerative changes in the inner ear. A detailed neurotological workup helps to diagnose VS of all sizes and can also provide useful prognostic information.

Children With Mild Bilateral and Unilateral Hearing Loss: Parents’ Reflections on Experiences and Outcomes

Science.gov (United States)

Fitzpatrick, Elizabeth; Grandpierre, Viviane; Durieux-Smith, Andrée; Gaboury, Isabelle; Coyle, Doug; Na, Eunjung; Sallam, Nusaiba

2016-01-01

Abstract Children with mild bilateral and unilateral hearing loss are now commonly identified early through newborn hearing screening initiatives. There remains considerable uncertainty about how to support parents and about which services to provide for children with mild bilateral and unilateral hearing loss. The goal of this study was to learn about parents’ experiences and understand, from their perspectives, the impact of hearing loss in the mild range on the child’s functioning. Parents of 20 children in Ontario, Canada, participated in the study. The median age of identification of hearing loss was 4.6 months (interquartile range: 3.6, 10.8). Parents appreciated learning early about hearing loss, but their experiences with the early process were mixed. Parents felt that professionals minimized the importance of milder hearing loss. There was substantial uncertainty about the need for hearing aids and the findings suggest that parents need specific guidance. Parents expressed concerns about the potential impact of hearing loss on their child’s development, particularly at later ages. PMID:26433195

Framing susceptibility in a risky choice game is altered by galvanic vestibular stimulation.

Science.gov (United States)

Preuss, Nora; Kalla, Roger; Müri, Rene; Mast, Fred W

2017-06-07

Recent research provides evidence that galvanic vestibular stimulation (GVS) has a modulating effect on somatosensory perception and spatial cognition. However, other vestibular stimulation techniques have induced changes in affective control and decision making. The aim of this study was to investigate the effect of GVS on framing susceptibility in a risky-choice game. The participants were to decide between a safe and a risky option. The safe option was framed either positively or negatively. During the task, the participants were exposed to either left anodal/right cathodal GVS, right anodal/left cathodal GVS, or sham stimulation (control condition). While left anodal/right cathodal GVS activated more right-hemispheric vestibular brain areas, right anodal/left cathodal GVS resulted in more bilateral activation. We observed increased framing susceptibility during left anodal/right cathodal GVS, but no change in framing susceptibility during right anodal/left cathodal GVS. We propose that GVS results in increased reliance on the affect heuristic by means of activation of cortical and subcortical vestibular-emotional brain structures and that this effect is modulated by the lateralization of the vestibular cortex.

Refractory episodic vertigo: role of intratympanic gentamicin and vestibular evoked myogenic potentials,

Directory of Open Access Journals (Sweden)

Erika Celis-Aguilar

Full Text Available Abstract Introduction: Even today, the treatment of intractable vertigo remains a challenge. Vestibular ablation with intratympanic gentamicin stands as a good alternative in the management of refractory vertigo patients. Objective: To control intractable vertigo through complete saccular and horizontal canal vestibular ablation with intratympanic gentamicin treatment. Methods: Patients with refractory episodic vertigo were included. The inclusion criteria were: unilateral ear disease, moderate to profound sensorineural hearing loss, and failure to other treatments. Included patients underwent 0.5-0.8 mL of gentamicin intratympanic application at a 30 mg/mL concentration. Vestibular ablation was confirmed by the absence of response on cervical vestibular evoked myogenic potentials and no response on caloric tests. Audiometry, electronystagmography with iced water, and vestibular evoked myogenic potentials were performed in all patients. Results: Ten patients were included; nine patients with Meniere's disease and one patient with (late onset delayed hydrops. Nine patients showed an absent response on vestibular evoked myogenic potentials and no response on caloric tests. The only patient with low amplitude on cervical vestibular evoked myogenic potentials had vertigo recurrence. Vertigo control was achieved in 90% of the patients. One patient developed hearing loss >30 dB. Conclusions: Cervical vestibular evoked myogenic potentials confirmed vestibular ablation in patients treated with intratympanic gentamicin. High-grade vertigo control was due to complete saccular and horizontal canal ablation (no response to iced water in electronystagmography and no response on cervical vestibular evoked myogenic potentials.

Cost-effectiveness analysis of a non-contrast screening MRI protocol for vestibular schwannoma in patients with asymmetric sensorineural hearing loss

International Nuclear Information System (INIS)

Crowson, Matthew G.; Rocke, Daniel J.; Kaylie, David M.; Hoang, Jenny K.; Weissman, Jane L.

2017-01-01

We aimed to determine if a non-contrast screening MRI is cost-effective compared to a full MRI protocol with contrast for the evaluation of vestibular schwannomas. A decision tree was constructed to evaluate full MRI and screening MRI strategies for patients with asymmetric sensorineural hearing loss. If a patient were to have a positive screening MRI, s/he received a full MRI. Vestibular schwannoma prevalence, MRI specificity and sensitivity, and gadolinium anaphylaxis incidence were obtained through literature review. Institutional charge data were obtained using representative patient cohorts. One-way and probabilistic sensitivity analyses were completed to determine CE model threshold points for MRI performance characteristics and charges. The mean charge for a full MRI with contrast was significantly higher than a screening MRI ($4089 ± 1086 versus $2872 ± 741; p < 0.05). The screening MRI protocol was more cost-effective than a full MRI protocol with a willingness-to-pay from $0 to 20,000 USD. Sensitivity analyses determined that the screening protocol dominated when the screening MRI charge was less than $4678, and the imaging specificity exceeded 78.2%. The screening MRI protocol also dominated when vestibular schwannoma prevalence was varied between 0 and 1000 in 10,000 people. A screening MRI protocol is more cost-effective than a full MRI with contrast in the diagnostic evaluation of a vestibular schwannoma. A screening MRI likely also confers benefits of shorter exam time and no contrast use. Further investigation is needed to confirm the relative performance of screening protocols for vestibular schwannomas. (orig.)

Cost-effectiveness analysis of a non-contrast screening MRI protocol for vestibular schwannoma in patients with asymmetric sensorineural hearing loss

Energy Technology Data Exchange (ETDEWEB)

Crowson, Matthew G.; Rocke, Daniel J.; Kaylie, David M. [Duke University Medical Center, Division of Otolaryngology-Head and Neck Surgery, Durham, NC (United States); Hoang, Jenny K. [Duke University Medical Center, Department of Radiology, Durham, NC (United States); Weissman, Jane L. [Oregon Health Sciences University, Professor Emerita of Diagnostic Radiology, Portland, OR (United States)

2017-08-15

We aimed to determine if a non-contrast screening MRI is cost-effective compared to a full MRI protocol with contrast for the evaluation of vestibular schwannomas. A decision tree was constructed to evaluate full MRI and screening MRI strategies for patients with asymmetric sensorineural hearing loss. If a patient were to have a positive screening MRI, s/he received a full MRI. Vestibular schwannoma prevalence, MRI specificity and sensitivity, and gadolinium anaphylaxis incidence were obtained through literature review. Institutional charge data were obtained using representative patient cohorts. One-way and probabilistic sensitivity analyses were completed to determine CE model threshold points for MRI performance characteristics and charges. The mean charge for a full MRI with contrast was significantly higher than a screening MRI ($4089 ± 1086 versus $2872 ± 741; p < 0.05). The screening MRI protocol was more cost-effective than a full MRI protocol with a willingness-to-pay from $0 to 20,000 USD. Sensitivity analyses determined that the screening protocol dominated when the screening MRI charge was less than $4678, and the imaging specificity exceeded 78.2%. The screening MRI protocol also dominated when vestibular schwannoma prevalence was varied between 0 and 1000 in 10,000 people. A screening MRI protocol is more cost-effective than a full MRI with contrast in the diagnostic evaluation of a vestibular schwannoma. A screening MRI likely also confers benefits of shorter exam time and no contrast use. Further investigation is needed to confirm the relative performance of screening protocols for vestibular schwannomas. (orig.)

Modified Willet′s appliance for bilateral loss of multiple deciduous molars: A case report

Directory of Open Access Journals (Sweden)

Dhindsa A

2008-09-01

Full Text Available No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a variety of problems. Thus, the conventional designs are required to be modified according to the needs of the patient. Therefore, this paper describes an entirely new design of the Willet′s appliance in cases of bilateral loss of deciduous molars before the eruption of first permanent molar.

Refractory episodic vertigo: role of intratympanic gentamicin and vestibular evoked myogenic potentials.

Science.gov (United States)

Celis-Aguilar, Erika; Hinojosa-González, Ramon; Vales-Hidalgo, Olivia; Coutinho-Toledo, Heloisa

Even today, the treatment of intractable vertigo remains a challenge. Vestibular ablation with intratympanic gentamicin stands as a good alternative in the management of refractory vertigo patients. To control intractable vertigo through complete saccular and horizontal canal vestibular ablation with intratympanic gentamicin treatment. Patients with refractory episodic vertigo were included. The inclusion criteria were: unilateral ear disease, moderate to profound sensorineural hearing loss, and failure to other treatments. Included patients underwent 0.5-0.8mL of gentamicin intratympanic application at a 30mg/mL concentration. Vestibular ablation was confirmed by the absence of response on cervical vestibular evoked myogenic potentials and no response on caloric tests. Audiometry, electronystagmography with iced water, and vestibular evoked myogenic potentials were performed in all patients. Ten patients were included; nine patients with Meniere's disease and one patient with (late onset) delayed hydrops. Nine patients showed an absent response on vestibular evoked myogenic potentials and no response on caloric tests. The only patient with low amplitude on cervical vestibular evoked myogenic potentials had vertigo recurrence. Vertigo control was achieved in 90% of the patients. One patient developed hearing loss >30dB. Cervical vestibular evoked myogenic potentials confirmed vestibular ablation in patients treated with intratympanic gentamicin. High-grade vertigo control was due to complete saccular and horizontal canal ablation (no response to iced water in electronystagmography and no response on cervical vestibular evoked myogenic potentials). Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Rapid limb-specific modulation of vestibular contributions to ankle muscle activity during locomotion

NARCIS (Netherlands)

Forbes, P.A.; Vlutters, M; Dakin, CJ; van der Kooij, H.; Blouin, JS; Schouten, A.C.

2017-01-01

During walking, the vestibular influence on locomotor activity is phase-dependent and modulated in both limbs with changes in velocity. It is unclear, however, whether this bilateral modulation is due to a coordinated mechanism between both limbs or instead through limb-specific processes that

Função cócleo-vestibular após hemisferectomias cerebrais: apresentação de dois casos

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Sérgio Paula Santos

1957-03-01

Full Text Available O exame cócleo-vestibular de dois pacientes hemisferectomizados mostrou: hipoacusia bilateral não ultrapassando 30 db, sendo maior no ouvido contralateral; não houve recrutamento de volume; desproporção entre audiometria vocal e tonal; a função vestibular não se mostrou prejudicada pela prova calórica fria.

Central adaptation to repeated galvanic vestibular stimulation: implications for pre-flight astronaut training.

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Valentina Dilda

Full Text Available Healthy subjects (N = 10 were exposed to 10-min cumulative pseudorandom bilateral bipolar Galvanic vestibular stimulation (GVS on a weekly basis for 12 weeks (120 min total exposure. During each trial subjects performed computerized dynamic posturography and eye movements were measured using digital video-oculography. Follow up tests were conducted 6 weeks and 6 months after the 12-week adaptation period. Postural performance was significantly impaired during GVS at first exposure, but recovered to baseline over a period of 7-8 weeks (70-80 min GVS exposure. This postural recovery was maintained 6 months after adaptation. In contrast, the roll vestibulo-ocular reflex response to GVS was not attenuated by repeated exposure. This suggests that GVS adaptation did not occur at the vestibular end-organs or involve changes in low-level (brainstem-mediated vestibulo-ocular or vestibulo-spinal reflexes. Faced with unreliable vestibular input, the cerebellum reweighted sensory input to emphasize veridical extra-vestibular information, such as somatosensation, vision and visceral stretch receptors, to regain postural function. After a period of recovery subjects exhibited dual adaption and the ability to rapidly switch between the perturbed (GVS and natural vestibular state for up to 6 months.

Central adaptation to repeated galvanic vestibular stimulation: implications for pre-flight astronaut training.

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Dilda, Valentina; Morris, Tiffany R; Yungher, Don A; MacDougall, Hamish G; Moore, Steven T

2014-01-01

Healthy subjects (N = 10) were exposed to 10-min cumulative pseudorandom bilateral bipolar Galvanic vestibular stimulation (GVS) on a weekly basis for 12 weeks (120 min total exposure). During each trial subjects performed computerized dynamic posturography and eye movements were measured using digital video-oculography. Follow up tests were conducted 6 weeks and 6 months after the 12-week adaptation period. Postural performance was significantly impaired during GVS at first exposure, but recovered to baseline over a period of 7-8 weeks (70-80 min GVS exposure). This postural recovery was maintained 6 months after adaptation. In contrast, the roll vestibulo-ocular reflex response to GVS was not attenuated by repeated exposure. This suggests that GVS adaptation did not occur at the vestibular end-organs or involve changes in low-level (brainstem-mediated) vestibulo-ocular or vestibulo-spinal reflexes. Faced with unreliable vestibular input, the cerebellum reweighted sensory input to emphasize veridical extra-vestibular information, such as somatosensation, vision and visceral stretch receptors, to regain postural function. After a period of recovery subjects exhibited dual adaption and the ability to rapidly switch between the perturbed (GVS) and natural vestibular state for up to 6 months.

Gradual Recovery from Bilateral Severe Sensorineural Hearing Loss post Motor Vehicle Accident.

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Yaroko, A A; Shahrjerdi, B; M D, Md Khairi

2013-04-01

Sensorineural hearing loss following trauma is a common finding in daily clinical practice and usually associated with a poor prognosis. Our case illustrates a patient who was involved in motor vehicle accident sustaining bilateral severe to profound sensorineural hearing loss but subsequently recovered fully after two years. Unless there is clear trauma to the cochlea or auditory nerve, a substantial duration of follow up is needed in the treatment of such cases.

Clinical evaluation of elderly people with chronic vestibular disorder.

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Gazzola, Juliana Maria; Ganança, Fernando Freitas; Aratani, Mayra Cristina; Perracini, Monica Rodrigues; Ganança, Maurício Malavasi

2006-01-01

Dizziness is common among the elderly. To characterize social, demographic, clinical, functional and otoneurological data in elderly patients with chronic vestibular disorder. A sequential study of 120 patients with chronic vestibular disorder. Simple descriptive analyses were undertaken. 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 patients were taking on average 3.86+/-2.27 different medications. The most prevalent diagnosis on the vestibular exam was unilateral vestibular loss (29.8%) and the most prevalent etiology was metabolic vestibulopathy (40.0%) followed by benign paroxysmal positional vertigo (36.7%). Fifty-two patients (43.3%) had experienced dizziness for 5 years or more. Sixty-four patients (53.3%) had at least one fall in the last year and thirty-five (29.2%) had recurrent falls. Most of the sample included females with associated diseases, and using many different drugs. The most prevalent vestibular diseases were metabolic and vascular labyrinth conditions. Dizziness is a chronic symptom in elderly patients. The association of two vestibular diseases is common. Falls are prevalent in chronic dizzy elderly patients.

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

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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

Sinonasal carcinoma presenting as chronic sinusitis and sequential bilateral visual loss

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Wei-Yu Chiang

2015-01-01

Full Text Available Sinonasal undifferentiated carcinoma-related rhinogenic optic neuropathy is rare and may lead to visual loss. To the best of our knowledge, this is the first report of bilateral sequential visual loss induced by this etiology. It is important to differentiate between chronic sinusitis and malignancy on the basis of specific findings on magnetic resonance images. Surgical decompression with multidisciplinary therapy, including steroids, chemotherapy, and radiotherapy, is indicated. However, no visual improvement was noted in this case, emphasizing the rapid disease progression and importance of early diagnosis and treatment.

Baseline vestibular and auditory findings in a trial of post-concussive syndrome

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Meehan, Anna; Searing, Elizabeth; Weaver, Lindell; Lewandowski, Andrew

2016-01-01

Previous studies have reported high rates of auditory and vestibular-balance deficits immediately following head injury. This study uses a comprehensive battery of assessments to characterize auditory and vestibular function in 71 U.S. military service members with chronic symptoms following mild traumatic brain injury that did not resolve with traditional interventions. The majority of the study population reported hearing loss (70%) and recent vestibular symptoms (83%). Central auditory deficits were most prevalent, with 58% of participants failing the SCAN3:A screening test and 45% showing abnormal responses on auditory steady-state response testing presented at a suprathreshold intensity. Only 17% of the participants had abnormal hearing (⟩25 dB hearing loss) based on the pure-tone average. Objective vestibular testing supported significant deficits in this population, regardless of whether the participant self-reported active symptoms. Composite score on the Sensory Organization Test was lower than expected from normative data (mean 69.6 ±vestibular tests, vestibulo-ocular reflex, central auditory dysfunction, mild traumatic brain injury, post-concussive symptoms, hearing15.6). High abnormality rates were found in funduscopy torsion (58%), oculomotor assessments (49%), ocular and cervical vestibular evoked myogenic potentials (46% and 33%, respectively), and monothermal calorics (40%). It is recommended that a full peripheral and central auditory, oculomotor, and vestibular-balance evaluation be completed on military service members who have sustained head trauma.

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

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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.

Pulsed infrared radiation excites cultured neonatal spiral and vestibular ganglion neurons by modulating mitochondrial calcium cycling.

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Lumbreras, Vicente; Bas, Esperanza; Gupta, Chhavi; Rajguru, Suhrud M

2014-09-15

Cochlear implants are currently the most effective solution for profound sensorineural hearing loss, and vestibular prostheses are under development to treat bilateral vestibulopathies. Electrical current spread in these neuroprostheses limits channel independence and, in some cases, may impair their performance. In comparison, optical stimuli that are spatially confined may result in a significant functional improvement. Pulsed infrared radiation (IR) has previously been shown to elicit responses in neurons. This study analyzes the response of neonatal rat spiral and vestibular ganglion neurons in vitro to IR (wavelength = 1,863 nm) using Ca(2+) imaging. Both types of neurons responded consistently with robust intracellular Ca(2+) ([Ca(2+)]i) transients that matched the low-frequency IR pulses applied (4 ms, 0.25-1 pps). Radiant exposures of ∼637 mJ/cm(2) resulted in continual neuronal activation. Temperature or [Ca(2+)] variations in the media did not alter the IR-evoked transients, ruling out extracellular Ca(2+) involvement or primary mediation by thermal effects on the plasma membrane. While blockage of Na(+), K(+), and Ca(2+) plasma membrane channels did not alter the IR-evoked response, blocking of mitochondrial Ca(2+) cycling with CGP-37157 or ruthenium red reversibly inhibited the IR-evoked [Ca(2+)]i transients. Additionally, the magnitude of the IR-evoked transients was dependent on ryanodine and cyclopiazonic acid-dependent Ca(2+) release. These results suggest that IR modulation of intracellular calcium cycling contributes to stimulation of spiral and vestibular ganglion neurons. As a whole, the results suggest selective excitation of neurons in the IR beam path and the potential of IR stimulation in future auditory and vestibular prostheses. Copyright © 2014 the American Physiological Society.

Cochleo-vestibular clinical findings among drug resistant Tuberculosis Patients on therapy-a pilot study

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Ramma Lebogang

2012-01-01

Full Text Available Abstracts Background To investigate the Cochleo-vestibular clinical and audiometric findings in Multi and Extreme Drug Resistance(MDR and XDR tuberculosis(TB patients on treatment and make recommendations. Methods A cross-sectional study of adult MDR and XDR-TB patients was conducted in a general hospital in Cape-Town-South-Africa. Ethical approval was secured and all consenting patients administered with pretested and validated questionnaire under the guidance of International Classification of Functioning, Disability and Health(ICF Checklist-version-2.1a. Audiometric evaluation included: Otoscopy, Diagnostic Audiometry and Tympanometry. The data analyses were done with SPSS version 16, Chi-square and StatCalc-7. Results Fifty-three adults, ages 18-60 (mean-33 years comprising 26 males and 27 females participated in the study. Hospital stay duration varied from 1-18 months (mean-6 months and all were on anti-Koch's second line drugs (regimen 2. MDR TB group were 45(85% and XDR 8(15%. Vertigo was the most common vestibular symptoms, 24(45% whereas, tinnitus 23(42% and hearing loss 13(25% were most frequent auditory complaints. Bilateral sensorineural hearing losses of varying degrees were confirmed in 23(47%. There was no association between gender and age with hearing loss [χ2 (P = 0.16, ά = 0.05 and (p = 0.13, ά = 0.05]. Furthermore, MDR and XTR TB groups [20/42 Vs 3/8; Z = 0.46 and P = 0.64], showed no difference in pattern of the hearing losses. Conclusions A multi-disciplinary close surveillance of MDR and XDR TB patients on therapy is imperative. Finally, researches into therapeutic trials on antidotes and potent safer substitutes for aminoglycosides in the management are recommended.

Regeneration of hair cells in the mammalian vestibular system.

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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.

Prospective radiological study concerning a series of patients suffering from conductive or mixed hearing loss due to superior semicircular canal dehiscence.

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Martin, Christian; Chahine, Pierre; Veyret, Charles; Richard, Céline; Prades, Jean Michel; Pouget, Jean François

2009-08-01

The aim of this study is to appreciate the incidence of patients with isolated conductive hearing loss with normal drum due to superior semicircular canal dehiscence (SCD). It is a prospective radiological study. Two hundred and seventy-two patients with a normal drum suffering from isolated unilateral or bilateral conductive or mixed hearing loss were included in a prospective radiological study. A high resolution computerized tomography (HRCT) was performed in all the patients. Those who were found to have a unilateral or bilateral SCD underwent further etiological, clinical, audiologic evaluation. Ten patients with conductive or mixed hearing loss were found to have a unilateral or bilateral SCD. The disease was bilateral in five cases, and most often associated with a dehiscence of the tegmen tympani on both sides, supporting the theory of the congenital nature of the disease. There was no clear correlation between symptoms and the size of the SCD. Because patients were not suffering from incapacitating vestibular symptoms, they were not operated for surgical occlusion of the SCD, and were referred to a hearing aid specialist to improve hearing. Conductive or mixed hearing loss due to SCD is relatively frequent, justifying in our opinion that a systematic HRCT be carried out before surgery of any patient with conductive hearing loss.

Role of the cerebellum and the vestibular apparatus in regulation of orthostatic reflexes in the cat

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Doba, N.; Reis, D. J.

1974-01-01

The contribution of the fastigial nucleus and the vestibular nerves (eighth cranial nerves) to the orthostatic reflexes in anesthetized, paralyzed cats was studied. Bilateral lesions of the rostral fastigial nucleus resulted in impairment of the reflex changes in blood pressure, femoral arterial flow, and resistance evoked by head-up tilting to 30 deg or 60 deg. The rostral fastigial nucleus, which might be triggered by the vestibular apparatus, appears to participate in concert with the baroreceptors in the initiation and possibly the maintenance of the orthostatic reflexes.

The vestibular implant: Frequency-dependency of the electrically evoked Vestibulo-Ocular Reflex in humans

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Raymond eVan De Berg

2015-01-01

Full Text Available The Vestibulo-Ocular Reflex (VOR shows frequency-dependent behavior. This study investigated whether the characteristics of the electrically evoked VOR (eVOR elicited by a vestibular implant, showed the same frequency-dependency.Twelve vestibular electrodes implanted in 7 patients with bilateral vestibular hypofunction were tested. Stimuli consisted of amplitude-modulated electrical stimulation with a sinusoidal profile at frequencies of 0.5Hz, 1Hz, and 2Hz. The main characteristics of the eVOR were evaluated and compared to the natural VOR characteristics measured in a group of age-matched healthy volunteers who were subjected to horizontal whole body rotations with equivalent sinusoidal velocity profiles at the same frequencies.A strong and significant effect of frequency was observed in the total peak eye velocity of the eVOR. This effect was similar to that observed in the natural VOR. Other characteristics of the (eVOR (angle, habituation-index, and asymmetry showed no significant frequency-dependent effect. In conclusion, this study demonstrates that, at least at the specific (limited frequency range tested, responses elicited by a vestibular implant closely mimic the frequency-dependency of the normal vestibular system.

[Clinical research of vestibular autorotation test for patients with vertebrobasilar insufficiency].

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Chen, Tai-sheng; Wang, Wen-hong; Song, Wei; Lu, Hong-hua; Zuo, Xian-hua; Zhang, Jin-mei

2006-10-01

To explore the diagnostic values of vestibular autorotation test (VAT) for patients with vertebrobasilar insufficiency (VBI). VAT and videonystagmography ( VNG) were performed on 73 patients with VBI and 48 patients with peripheral vestibular lesions (contrast group). Parameters analyzed included Gain, phase and asymmetry of VAT, as well as the canal paresis (CP) of caloric test and results of optokinetic-pursuit tests in VNG. Positive result of the test could be defined if anyone of the parameters was abnormal. For VAT test, Gain was enhanced in VBI group and was reduced in contrast group. In VBI group and contrast group, Gain enhanced showed in 47 (64.4%) cases and 5 (10.4%) cases, respectively (chi2 = 31.19, P VNG test, results with optokinetic-pursuit tests were more abnormal in VBI group than that in contrast group, which showed central lesions characteristics. Forty-four cases (60.3%) in VBI group and 10 cases (20.8%) in control group showed central lesions results with optokinetic-pursuit tests and visual fixation test (chi2 = 15.89, P < 0.01). Unilateral or bilateral CP showed in 33 cases (68.6%) in control group and 51 cases (69.9%) in VBI group with caloric test. Gain of VAT is mostly enhanced in VBI group, and Gain as a main characteristic is reduced in patients with peripheral vestibular lesions. The Gain parameter is availability for assessing characteristics of vestibular lesions. Phase and asymmetry can be used to assess the vestibular function but can not indicate the characteristics of vestibular lesions.

Screening of SLC26A4, FOXI1, KCNJ10, and GJB2 in bilateral deafness patients with inner ear malformation.

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Chen, Kaitian; Wang, Xianren; Sun, Liang; Jiang, Hongyan

2012-06-01

Bilateral nonsyndromic sensorineural hearing loss associated with inner ear malformation is closely related to genetics. SLC26A4 is considered to be the major involved gene. Recently, FOXI1 and KCNJ10 mutations have been linked to enlarged vestibular aqueducts and GJB2 mutations linked to temporal bone malformation. The authors aimed to investigate the mutation spectrums of these genes in Chinese patients with bilateral hearing impairment associated with inner ear malformation. Cross-sectional study. Affiliated hospital of the university. The authors analyzed the GJB2, SLC26A4, FOXI1, and KCNJ10 gene sequences in 43 patients presenting with bilateral hearing impairment associated with inner ear malformation using pyrosequencing and direct DNA sequencing. In total, 74.4% (32/43) of patients carried at least 1 of 14 pathogenic SLC26A4 mutations, including 6 novel mutations and 4 polymorphisms. Patients with enlarged vestibular aqueducts had a higher rate of SLC26A4 mutation than Mondini dysplasia patients. No FOXI1 or KCNJ10 potential pathogenic mutation was present, and GJB2 biallelic pathogenic mutations were uncommon (2.3%; 1/43). No significant correlation was observed between the genotype and phenotype of SLC26A4 mutations. SLC26A4 accounts for 74.4% of inner ear malformations in our cohort, whereas FOXI1, KCNJ10, and GJB2 mutations are not common. Other possible genes or external factors may contribute to this multibranch abnormality.

Vestibular Dysfunction in Wernicke’s Encephalopathy: Predominant Impairment of the Horizontal Semicircular Canals

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Seung-Han Lee

2018-03-01

Full Text Available BackgroundWernicke’s encephalopathy (WE, a metabolic disorder due to thiamine deficiency, manifests with various neurological symptoms and signs. It has been known as a cause of vestibular dysfunction. Preliminary reports have proposed predominant involvement of the horizontal semicircular canals (HSCs.ObjectiveTo better characterize the pattern of vestibular impairment in patients with WE using quantitative video head-impulse testing and to review the literature regarding this topic.MethodFrom January 2014 to December 2016, we retrospectively enrolled five cases of WE that received quantitative video-head-impulse testing (vHIT. We retrieved the clinical features from the medical records and reviewed quantitative head-impulse testing (qHIT and caloric irrigation. Based on the gain and the number of corrective saccades, the function (normal vs. impaired of each semicircular canal was rated. In addition, we conducted a MEDLINE and EMBASE search to identify other published cases of WE that had received qHIT. Neuro-otologic and neuro-ophthalmologic findings and vestibular testing results were extracted.ResultsA total of 17 patients (own series = 5; published cases = 12 aged 54.6 ± 11 years were included. Key neurologic findings were ataxia of stance and gait (13/13, 100%, spontaneous nystagmus (7/14, 50%, gaze-evoked nystagmus (GEN (17/17, 100%, positive bedside head-impulse testing for the horizontal canals (16/17, 94%, and memory impairment and mental changes (6/11, 54.5%. Regarding vestibular testing, qHIT (either video based or search-coil based documented selective bilateral horizontal canal dysfunction with normal or minimal vertical canal impairment (14/14, 100%. On caloric irrigation, bilateral horizontal canal paresis was noted in most cases (10/11, 91%.ConclusionIn WE, signs of both peripheral and central vestibular dysfunction (i.e., GEN, ataxia of stance and gait, abnormal head-impulse testing were common. Selective or

Use of cooperative game theory concepts for loss allocation in bilateral electricity markets

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Satyaramesh, P.V.; Radhakrishna, C.

2009-01-01

The deregulation of electricity markets has resulted in changes in electricity pricing. Participants in a deregulated market require a fair and equitable pricing structure that reflects both the share of power produced and consumed in the network, as well as the cost of power loss caused by users. This paper focused on the allocation of losses using the cooperative game theory (CGT) where many transactions take place in a bilateral electricity market environment. A set of approaches documented in literature in the areas of application of CGT were first identified and their applicability to allocations of losses in bilateral electricity markets were then reviewed. The allocation methods can be classified into 3 broad categories, namely classical, new, and variants of nucleolus. The structure of the game and the concept of fairness behind it were the 2 points that were examined in detail in this study. The allocation concept of these methods was systematically analyzed and compared. Calculations were performed on a six-bus system sample and a standard IEEE 14-bus system. The variants of nucleolus were shown to be among the most plausible concepts. The power losses for each transaction were calculated using a power flow procedure. 16 refs., 4 tabs., 1 fig.

Use of cooperative game theory concepts for loss allocation in bilateral electricity markets

Energy Technology Data Exchange (ETDEWEB)

Satyaramesh, P.V. [AP Transco, Hyderabad, AP (India); Radhakrishna, C. [Global Energy Consulting Engineers Private Ltd., Hyderabad, AP (India)

2009-07-01

The deregulation of electricity markets has resulted in changes in electricity pricing. Participants in a deregulated market require a fair and equitable pricing structure that reflects both the share of power produced and consumed in the network, as well as the cost of power loss caused by users. This paper focused on the allocation of losses using the cooperative game theory (CGT) where many transactions take place in a bilateral electricity market environment. A set of approaches documented in literature in the areas of application of CGT were first identified and their applicability to allocations of losses in bilateral electricity markets were then reviewed. The allocation methods can be classified into 3 broad categories, namely classical, new, and variants of nucleolus. The structure of the game and the concept of fairness behind it were the 2 points that were examined in detail in this study. The allocation concept of these methods was systematically analyzed and compared. Calculations were performed on a six-bus system sample and a standard IEEE 14-bus system. The variants of nucleolus were shown to be among the most plausible concepts. The power losses for each transaction were calculated using a power flow procedure. 16 refs., 4 tabs., 1 fig.

Playing Music May Improve the Gait Pattern in Patients with Bilateral Caloric Areflexia Wearing a Cochlear Implant: Results from a Pilot Study

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Ann Hallemans

2017-08-01

Full Text Available HypothesisAuditory information through an active cochlear implant (CI influences gait parameters in adults with bilateral caloric areflexia and profound sensorineural hearing loss.BackgroundPatients with bilateral caloric areflexia suffer from imbalance, resulting in an increased risk of falling. In case of simultaneous deafness, the lack of auditory feedback results in less awareness of the auditory scene. This combination might produce significant challenges while walking and navigating. Auditory cues can be restored to some extent with a CI. Electrical stimulation through a CI can also produce a vestibulocollic reflex through current spread, which can be measured as cervical vestibular-evoked myogenic potentials.MethodsAdults (seven males, one female, mean age 61 ± 14 years, wearing a CI to treat profound sensorineural hearing loss and presenting with bilateral caloric areflexia walked barefoot, over ground, at self-selected speed in three different conditions: with CI turned on, while listening to music and with CI turned off. Spatiotemporal and kinematic parameters of gait were calculated using the conventional gait model.ResultsRemoving auditory feedback by turning off the CI decreased stride time (mean difference 0.03 ± 0.15 s and slightly increased stride length (mean difference 0.5 ± 1.2 cm compared to the control condition with the CI on. Walking while playing music positively affected gait compared to walking with the CI on but without auditory feedback. By increasing the motion of the pelvis (mean difference 1.3° ± 0.4°, the knee (mean difference 3.9° ± 0.8° and the ankle (mean difference 2.2° ± 0.2°, stride length increased (7.8 ± 1.2 cm, while stride time decreased (0.059 ± 0.016 s.ConclusionAlthough a practice effect cannot be completely ruled out, this pilot study suggests that playing music while wearing an active CI may improve gait in patients with bilateral otovestibular

Vestibular characterization in the menstrual cycle Caracterização vestibular no ciclo menstrual

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Cintia Ishii

2009-06-01

Full Text Available Hormonal disorders in the menstrual cycle can affect labyrinthine fluid homeostasis, causing balance and hearing dysfunctions. STUDY DESIGN: Clinical prospective. AIM: compare the results from vestibular tests in young women, in the premenstrual and postmenstrual periods. MATERIALS AND METHODS: twenty women were selected with ages ranging from 18 to 35 years, who were not using any kind of contraceptive method for at least six months, and without vestibular or hearing complaints. The test was carried out in each subject before and after the menstrual period, respecting the limit of ten days before or after menstruation. RESULTS: there was a statistically significant difference in the menstrual cycle phases only in the following vestibular tests: calibration, saccadic movements, PRPD and caloric-induced nystagmus. We also noticed that age; a regular menstrual cycle; hearing loss or dizziness cases in the family; and premenstrual symptoms such as tinnitus, headache, sleep disorders, anxiety, nausea and hyperacusis can interfere in the vestibular test. CONCLUSION: there are differences in the vestibular tests of healthy women when comparing their pre and postmenstrual periods.As alterações hormonais do ciclo menstrual podem comprometer a homeostase dos fluidos labirínticos, gerando alterações no equilíbrio e na audição. FORMA DO ESTUDO: Clínico prospectivo. OBJETIVO: Comparar os resultados dos testes do exame vestibular em mulheres jovens, nos períodos pré e pós-menstrual. MATERIAL E MÉTODO: Foram selecionadas vinte mulheres, entre dezoito e trinta e cinco anos, que não fizessem uso de qualquer tipo de anticoncepcional, com audição normal e sem queixas vestibulares. O exame vestibular foi realizado em cada participante no período pré e no período pós-menstrual, em ordem aleatória, e respeitando o limite de até dez dias antes do início da menstruação e até dez dias após o início da menstruação. RESULTADO: Foi observada

Craniopharyngioma causing bilateral vision loss 4 months after unremarkable magnetic resonance imaging of the brain

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Rainy Betts

2015-01-01

Full Text Available A 65-year-old man developed bilateral vision loss 4 months after magnetic resonance imaging demonstrated no lesion in the vicinity of the optic chiasm, hypothalamus, and suprasellar tissues. Repeat computed tomography 3 months later showed a predominantly cystic mass of the suprasellar cistern with extension into the anterior third ventricle, which histologically was a craniopharyngioma. The clinical course of this case fuels the controversy whether craniopharyngiomas arise from embryonic rests or can be acquired. From a clinical perspective, it raises questions about when to obtain imaging studies dedicated to the chiasm and the appropriate interval in which a scan should be repeated to exclude structural causes of bilateral vision loss.

Effect of Carbon Dioxide Laser on Increasing Vestibular Depth in Cleft Lip and Palate Patients.

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Yassaei, Sogra; Aghili, Hossein; Azam, Alireza Navab; Moghadam, Mahjobeh Gholdani; Safari, Isa

2017-09-01

Shallow upper buccal sulcus deformity in cleft lip and palate patients is one of the common secondary deformities after primary cleft lip and palate repair; this deformity may prevent or complicate orthodontic and prosthodontic procedures causing aesthetic and functional problems. A number of methods are described to increase the anterior maxillary sulcus in these patients. This study assessed the use of a carbon dioxide laser (CO 2 ) to increase the sulcus depth. Fifteen patients with cleft lip and palate (eight unilateral and seven bilateral) were studied. The surgical procedure was performed using CO 2 laser. The vestibular depth and lip length were measured at three time points namely before surgery (T0), 1 week following surgery (T1), and 4 months following surgery (T2). After data collection, statistical analyses were done using PASW ® version 18 SPSS. The mean values of vestibular depth were 9.46 ± 1.92, 13.83 ± 1.88, and 13.23 ± 1.76 mm for T0, T1, and T2, respectively. The vestibular depth significantly increased after 4 months of follow-up (p = 0.001). The mean amount of vestibular depth gain was not significantly different in unilateral and bilateral cleft groups (p = 0.908). The mean value of upper lip length increased by a mean of 1.23 mm and was statistically significant (p = 0.001). Upper buccal sulcus reconstruction with CO 2 laser provides successful and stable results. CO 2 laser application is suggested as an alternative to conventional vestibuloplasty.

Abnormal neural activities of directional brain networks in patients with long-term bilateral hearing loss.

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Xu, Long-Chun; Zhang, Gang; Zou, Yue; Zhang, Min-Feng; Zhang, Dong-Sheng; Ma, Hua; Zhao, Wen-Bo; Zhang, Guang-Yu

2017-10-13

The objective of the study is to provide some implications for rehabilitation of hearing impairment by investigating changes of neural activities of directional brain networks in patients with long-term bilateral hearing loss. Firstly, we implemented neuropsychological tests of 21 subjects (11 patients with long-term bilateral hearing loss, and 10 subjects with normal hearing), and these tests revealed significant differences between the deaf group and the controls. Then we constructed the individual specific virtual brain based on functional magnetic resonance data of participants by utilizing effective connectivity and multivariate regression methods. We exerted the stimulating signal to the primary auditory cortices of the virtual brain and observed the brain region activations. We found that patients with long-term bilateral hearing loss presented weaker brain region activations in the auditory and language networks, but enhanced neural activities in the default mode network as compared with normally hearing subjects. Especially, the right cerebral hemisphere presented more changes than the left. Additionally, weaker neural activities in the primary auditor cortices were also strongly associated with poorer cognitive performance. Finally, causal analysis revealed several interactional circuits among activated brain regions, and these interregional causal interactions implied that abnormal neural activities of the directional brain networks in the deaf patients impacted cognitive function.

Sudden bilateral sensorineural hearing loss as an unusual consequence of accidental ingestion of potassium hydroxide.

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Ciorba, A; Bovo, R; Castiglione, A; Pirodda, A; Martini, A

2010-01-01

To discuss the possible etiopathogenetic mechanism of inner ear damage induced by the ingestion of potassium hydroxide (KOH). We report the case of a 37-year-old patient with sudden bilateral sensorineural hearing loss after accidental ingestion of a KOH solution. The first ear, nose and throat examination disclosed only mild edema of the upper airways. He was treated in the intensive care unit and prescribed high-dose steroids, proton pump inhibitors and sucralfate for 2 weeks. Unfortunately, there was no recovery of the hearing loss, and no audiogram changes were noticed after 12 months of follow-up. After exploring the possible etiopathogenetic mechanism involved, the authors believe that in this case, a transient severe hemodynamic imbalance can actually be considered to be the most reliable explanation for the inner ear damage and subsequent onset of permanent bilateral sensorineural hearing loss. Copyright 2010 S. Karger AG, Basel.

Quality of life in patients after vestibular Schwannoma surgery

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Hajná, Barbora

2011-01-01

TVestibular schwannoma is a benign tumor that arises from the Schwann cells of the vestibular nerve. Unilateral hearing loss, tinnitus, facial and trigeminal dysfunction and vertigo are the most common symptoms. Surgical removal of the tumor is one of the treatment modalities of this disease. Surgical excision usually involves the complete vestibular nerve resection and there is also a risk of cochlear and facial nerve lesion. This thesis deals with changes in quality of life in patients afte...

Simultaneous bilateral laser therapy accelerates recovery after noise-induced hearing loss in a rat model

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Jae-Hun Lee

2016-07-01

Full Text Available Noise-induced hearing loss is a common type of hearing loss. The effects of laser therapy have been investigated from various perspectives, including in wound healing, inflammation reduction, and nerve regeneration, as well as in hearing research. A promising feature of the laser is its capability to penetrate soft tissue; depending on the wavelength, laser energy can penetrate into the deepest part of the body without damaging non-target soft tissues. Based on this idea, we developed bilateral transtympanic laser therapy, which uses simultaneous laser irradiation in both ears, and evaluated the effects of bilateral laser therapy on cochlear damage caused by noise overexposure. Thus, the purpose of this research was to assess the benefits of simultaneous bilateral laser therapy compared with unilateral laser therapy and a control. Eighteen Sprague-Dawley rats were exposed to narrow-band noise at 115 dB SPL for 6 h. Multiple auditory brainstem responses were measured after each laser irradiation, and cochlear hair cells were counted after the 15th such irradiation. The penetration depth of the 808 nm laser was also measured after sacrifice. Approximately 5% of the laser energy reached the contralateral cochlea. Both bilateral and unilateral laser therapy decreased the hearing threshold after noise overstimulation in the rat model. The bilateral laser therapy group showed faster functional recovery at all tested frequencies compared with the unilateral laser therapy group. However, there was no difference in the endpoint ABR results or final hair cell survival, which was analyzed histologically.

Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

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Farinoosh Fakharnia

2010-06-01

Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.

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

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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

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

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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 (pexercise 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.

Vestibular rehabilitation outcomes in the elderly with chronic vestibular dysfunction.

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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.

Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises

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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.

Bilateral cochlear implantation in a patient with bilateral temporal bone fractures.

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Chung, Jae Ho; Shin, Myung Chul; Min, Hyun Jung; Park, Chul Won; Lee, Seung Hwan

2011-01-01

With the emphasis on bilateral hearing nowadays, bilateral cochlear implantation has been tried out for bilateral aural rehabilitation. Bilateral sensorineural hearing loss caused by head trauma can get help from cochlear implantation. We present the case of a 44-year-old man with bilateral otic capsule violating temporal bone fractures due to head trauma. The patient demonstrated much improved audiometric and psychoacoustic performance after bilateral cochlear implantation. We believe bilateral cochlear implantation in such patient can be a very effective tool for rehabilitation. Copyright © 2011 Elsevier Inc. All rights reserved.

Immunohistochemical characterisation and localisation of cannabinoid CB1 receptor protein in the rat vestibular nucleus complex and the effects of unilateral vestibular deafferentation.

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Ashton, John C; Zheng, Yiwen; Liu, Ping; Darlington, Cynthia L; Smith, Paul F

2004-09-24

CB1 receptor expression has been reported to be low in the brainstem compared with the forebrain, and low in the vestibular nucleus complex (VNC) compared with other regions in the brainstem. However, a frequent effect of cannabis is dizziness and loss of balance. This may be due to the activation of cannabinoid receptors in the central vestibular pathways. We used immunohistochemistry to study the distribution of CB1 receptor protein in the VNC, and Western blotting to measure CB1 receptor expression in the VNC following unilateral vestibular deafferentation (UVD); the hippocampal CA1, CA2/3 and dentate gyrus (DG) regions were also analysed for comparison. This study confirms a previous electrophysiological demonstration that CB1 receptors exist in significant densities in the VNC and are likely to contribute to the neurochemical control of the vestibular reflexes. Nonetheless, CB1 receptor expression did not change significantly in the VNC during vestibular compensation. In addition, despite some small but significant changes in CB1 receptor expression in the CA2/3 and the DG following UVD, in no case were these differences statistically significant in comparison to both control groups.

Contribuição do potencial evocado auditivo em pacientes com vertigem Results of brainstem evoked response in patients with vestibular complaints

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Gisiane Munaro

2010-06-01

-sectional, retrospective, observational study, held with 56 dizzy patients assessed by means of audiometry, vecto-electronystagmography and brainstem evoked auditory potential, broken down into Group A, with 31 normal-hearing individuals and Group B with 25 hearing loss patients, compared to the control group made up of ten normal-hearing asymptomatic individuals. RESULTS: Patients from groups A and B were compared to the Control Group, although with values within the normal range. A common finding for both groups was the lack of wave I at 80 dBHL and it happened bilaterally in four individuals (12.9% and unilaterally in three (9.6% for Group A; and bilaterally in eight individuals from Group B (32%. In the two cases in which vecto-electronystagmography showed central vestibular alteration, there were no changes to the evoked potential parameters. CONCLUSION: patients with vertigo, normal-hearing and hearing loss individuals had increased absolute latencies when compared to the Control Group

Annual rate of hearing loss falls after fractionated stereotactic irradiation for vestibular schwannoma

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Sakamoto, Touru; Shirato, Hiroki; Takeichi, Norihito; Aoyama, Hidefumi; Fukuda, Satoshi; Miyasaka, Kazuo

2001-01-01

Purpose: The rate of hearing loss in a population before and after irradiation was investigated to determine the effect of irradiation on hearing impairment. Methods and materials: In 72 patients with vestibular schwannoma who received fractionated stereotactic irradiation from 1992 to 1999, 21 had had their hearing levels examined 3 months or more before the treatment. The mean time between the initial examination and treatment was 18.6 months (range: 3-89 months), and the mean time between treatment and the last follow-up was 24.2 months (12-69 months). Thirty-six to 50 Gy in 20-25 fractions over 5 to 6 weeks was given using an X-ray beam from a linear accelerator. Pure tone average (PTA) was measured using the mean hearing level at five frequencies, and the annual rate of hearing loss was defined as [(hearing loss in PTA(dB))/(follow-up period (months)x12)]. Results: The actual cumulative curve of decrease in tumor size of 2 mm or more was 38.3% at 2 years and 80.0% at 3 years. The mean of hearing loss in PTA was 11.6±10.3 dB (-1 to 35 dB) from the initial examination to the start of irradiation and 11.9±14.4 dB (-14 to 37 dB) from the start of irradiation to the last follow-up. The mean annual rates of hearing loss before irradiation and in the 1st, 2nd, 3rd and 4th years after irradiation were, respectively, 18.6, 11.2, 6.2, 5.1, and 5.0 dB/year. The annual rates of hearing loss in the 2nd year (P=0.025) and 3rd year (P=0.018) were significantly slower than the rate before irradiation. Conclusions: The mean annual rate of hearing loss was higher before irradiation than after irradiation, and hearing loss slowed rather than accelerated after irradiation. Although hearing loss after the treatment was usually permanent, fractionated stereotactic irradiation was suggested to be effective to lower the rate of hearing loss

Vestibular perception following acute unilateral vestibular lesions.

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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

Bilateral hearing loss is associated with decreased nonverbal intelligence in US children aged 6 to 16 years.

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Emmett, Susan D; Francis, Howard W

2014-09-01

To evaluate the association between hearing loss and nonverbal intelligence in US children. The Third National Health and Nutrition Examination Survey (NHANES III) is a cross-sectional survey (1988-1994) that used complex multistage sampling design to produce nationally representative demographic and examination data. A total of 4,823 children ages 6 to 16 years completed audiometric evaluation and cognitive testing during NHANES III. Hearing loss was defined as low-frequency pure-tone average (PTA) >25 dB (0.5, 1, 2 kHz) or high-frequency PTA >25 dB (3, 4, 6, 8 kHz) and was designated as unilateral or bilateral. Nonverbal intelligence was measured using the Wechsler Intelligence Scale for Children-Revised block design subtest. Low nonverbal intelligence was defined as a standardized score intelligence scores differed between children with normal hearing (9.59) and children with bilateral (6.87; P = .02) but not unilateral (9.12; P = .42) hearing loss. Non-Hispanic black race/ethnicity and family income intelligence, respectively (odds ratio [OR]: 3.92; P intelligence compared to normal hearing children (OR: 5.77; P = .02). Unilateral hearing loss was not associated with higher odds of low nonverbal intelligence (OR: 0.73; P = .40). Bilateral but not unilateral hearing loss is associated with decreased nonverbal intelligence in US children. Longitudinal studies are urgently needed to better understand these associations and their potential impact on future opportunities. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Bilateral Hearing Loss is Associated with Decreased Nonverbal Intelligence in US Children Ages 6 to 16 Years

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Emmett, Susan D.; Francis, Howard W.

2017-01-01

Objectives To evaluate the association between hearing loss and nonverbal intelligence in US children. Study Design The Third National Health and Nutrition Examination Survey (NHANES III) is a cross-sectional survey (1988–1994) that used complex multistage sampling design to produce nationally representative demographic and examination data. Methods A total of 4823 children ages 6–16 years completed audiometric evaluation and cognitive testing during NHANES III. Hearing loss was defined as low frequency pure tone average (PTA)>25 decibels (dB) (0.5,1,2 kHz) or high frequency PTA>25dB (3,4,6,8 kHz) and was designated as unilateral or bilateral. Nonverbal intelligence was measured using the Wechsler Intelligence Scale for Children-Revised block design subtest. Low nonverbal intelligence was defined as a standardized score intelligence scores differed between children with normal hearing (9.59) and children with bilateral (6.87; p=0.02) but not unilateral (9.12; p=0.42) hearing loss. Non-Hispanic black race/ethnicity and family incomeintelligence, respectively (OR 3.92; pintelligence compared to normal hearing children (OR 5.77; p=0.02). Unilateral hearing loss was not associated with higher odds of low nonverbal intelligence (OR 0.73; p=0.40). Conclusion Bilateral but not unilateral hearing loss is associated with decreased nonverbal intelligence in US children. Longitudinal studies are urgently needed to better understand these associations and their potential impact on future opportunities. PMID:24913183

Reliability of inertial sensors in the assessment of patients with vestibular disorders: a feasibility study

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Sathish K. Sankarpandi

2017-02-01

Full Text Available Abstract Background Vestibular disorders affect an individual’s stability, balance, and gait and predispose them to falls. Traditional laboratory-based semi-objective vestibular assessments are intrusive and cumbersome provide little information about their functional ability. Commercially available wearable inertial sensors allow us to make this real life assessments objective, with a detailed view of their functional abilities. Timed Up and Go (TUG and Postural Sway tests are commonly used tests for gait and balance assessments. Our aim was to assess the feasibility, test-retest reliability and ability to classify fall status in individuals with vestibular disorders using parameters derived from the commercially available wearable system (inertial sensors and the Mobility Lab Software, APDM, Inc.. Methods We recruited 27 individuals diagnosed either with unilateral or bilateral vestibular loss on vestibular function testing. Instrumented Timed Up and Go (iTUG and Postural Sway (iSway were administered three times during the first session and then repeated at a similar time the following week. To evaluate within and between sessions reliability of the parameters the Intra-Class Correlation coefficient (ICC was used. Subsequently, the ability of reliable parameters (ICC ≥ 0.8 to classify fallers from non-fallers was estimated. Results The iTUG test parameters showed good within and between sessions’ reliability with mean ICC (between-sessions values of 0.81 ± 0.17 and 0.69 ± 0.15, respectively. For the iSway test, the relative figures were; 0.76 ± 0.13 and 0.71 ± 0.14, respectively. A retrospective falls classification analysis with past 12 months falls history data yielded an accuracy of 66.70% with an area under the curve of 0.79. Mean Distance from centre of COP (mm of accelerometer’s trajectory (m/s2 from the iSway test was the only significant parameter to classify fallers from non-fallers. Conclusions Using

Bilateral acute visual loss from Rathke's cleft cyst apoplexy in a patient with dengue fever

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Ana Cláudia De Franco Suzuki

2014-10-01

Full Text Available Hemorrhagic complications of optic pathway diseases are extremely rare causes of acute visual loss associated with dengue fever. In this paper we report a patient presenting with dengue fever and bilateral acute visual loss caused by chiasmal compression due to Rathke's cleft cyst apoplexy. Considering the importance of early diagnosis and treatment to visual recovery, apoplexy of sellar and suprasellar tumors should be considered in the differential diagnosis of patients with acute visual loss and dengue fever.

Vestibular vertigo and comorbid cognitive and psychiatric impairment: the 2008 National Health Interview Survey.

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Bigelow, Robin T; Semenov, Yevgeniy R; du Lac, Sascha; Hoffman, Howard J; Agrawal, Yuri

2016-04-01

Patients with vestibular disease have been observed to have concomitant cognitive and psychiatric dysfunction. We evaluated the association between vestibular vertigo, cognitive impairment and psychiatric conditions in a nationally representative sample of US adults. We performed a cross-sectional analysis using the 2008 National Health Interview Survey (NHIS), which included a Balance and Dizziness Supplement, and questions about cognitive function and psychiatric comorbidity. We evaluated the association between vestibular vertigo, cognitive impairment (memory loss, difficulty concentrating, confusion) and psychiatric diagnoses (depression, anxiety and panic disorder). We observed an 8.4% 1-year prevalence of vestibular vertigo among US adults. In adjusted analyses, individuals with vestibular vertigo had an eightfold increased odds of 'serious difficulty concentrating or remembering' (OR 8.3, 95% CI 4.8 to 14.6) and a fourfold increased odds of activity limitation due to difficulty remembering or confusion (OR 3.9, 95% CI 3.1 to 5.0) relative to the rest of the US adults. Individuals with vestibular vertigo also had a threefold increased odds of depression (OR 3.4, 95% CI 2.9 to 3.9), anxiety (OR 3.2, 95% CI 2.8 to 3.6) and panic disorder (OR 3.4, 95% CI 2.9 to 4.0). Our findings indicate that vestibular impairment is associated with increased risk of cognitive and psychiatric comorbidity. The vestibular system is anatomically connected with widespread regions of the cerebral cortex, hippocampus and amygdala. Loss of vestibular inputs may lead to impairment of these cognitive and affective circuits. Further longitudinal research is required to determine if these associations are causal. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Audio-vestibular signs and symptoms in Chiari malformation type i. Case series and literature review.

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Guerra Jiménez, Gloria; Mazón Gutiérrez, Ángel; Marco de Lucas, Enrique; Valle San Román, Natalia; Martín Laez, Rubén; Morales Angulo, Carmelo

2015-01-01

Chiari malformation is an alteration of the base of the skull with herniation through the foramen magnum of the brain stem and cerebellum. Although the most common presentation is occipital headache, the association of audio-vestibular symptoms is not rare. The aim of our study was to describe audio-vestibular signs and symptoms in Chiari malformation type i (CM-I). We performed a retrospective observational study of patients referred to our unit during the last 5 years. We also carried out a literature review of audio-vestibular signs and symptoms in this disease. There were 9 patients (2 males and 7 females), with an average age of 42.8 years. Five patients presented a Ménière-like syndrome; 2 cases, a recurrent vertigo with peripheral features; one patient showed a sudden hearing loss; and one case suffered a sensorineural hearing loss with early childhood onset. The most common audio-vestibular symptom indicated in the literature in patients with CM-I is unsteadiness (49%), followed by dizziness (18%), nystagmus (15%) and hearing loss (15%). Nystagmus is frequently horizontal (74%) or down-beating (18%). Other audio-vestibular signs and symptoms are tinnitus (11%), aural fullness (10%) and hyperacusis (1%). Occipital headache that increases with Valsalva manoeuvres and hand paresthesias are very suggestive symptoms. The appearance of audio-vestibular manifestations in CM-I makes it common to refer these patients to neurotologists. Unsteadiness, vertiginous syndromes and sensorineural hearing loss are frequent. Nystagmus, especially horizontal and down-beating, is not rare. It is important for neurotologists to familiarise themselves with CM-I symptoms to be able to consider it in differential diagnosis. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Temporal bone extramedullary hematopoiesis as a causeof pediatric bilateral conductive hearing loss:Case report and review of the literature.

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Lanigan, Alexander; Fordham, M Taylor

2017-06-01

Extramedullary hematopoiesis occurs in children with hemoglobinopathy and chronic anemia. The liver and spleen are often affected first, but other foci can develop to support erythrocyte demand. We report a case of a nine-year-old with beta thalassemia and temporal bone extramedullary hematopoiesis causing ossicular fixation and bilateral conductive hearing loss. There is only one case in the literature describing this phenomenon in pediatric patients, and this is the first case report of bilateral hearing loss from this physiologic phenomenon. Otolaryngologists should consider this etiology in patients with chronic anemia and conductive hearing loss in the absence of otitis media. Published by Elsevier B.V.

Differences between otolith- and semicircular canal-activated neural circuitry in the vestibular system.

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Uchino, Yoshio; Kushiro, Keisuke

2011-12-01

In the last two decades, we have focused on establishing a reliable technique for focal stimulation of vestibular receptors to evaluate neural connectivity. Here, we summarize the vestibular-related neuronal circuits for the vestibulo-ocular reflex, vestibulocollic reflex, and vestibulospinal reflex arcs. The focal stimulating technique also uncovered some hidden neural mechanisms. In the otolith system, we identified two hidden neural mechanisms that enhance otolith receptor sensitivity. The first is commissural inhibition, which boosts sensitivity by incorporating inputs from bilateral otolith receptors, the existence of which was in contradiction to the classical understanding of the otolith system but was observed in the utricular system. The second mechanism, cross-striolar inhibition, intensifies the sensitivity of inputs from both sides of receptive cells across the striola in a single otolith sensor. This was an entirely novel finding and is typically observed in the saccular system. We discuss the possible functional meaning of commissural and cross-striolar inhibition. Finally, our focal stimulating technique was applied to elucidate the different constructions of axonal projections from each vestibular receptor to the spinal cord. We also discuss the possible function of the unique neural connectivity observed in each vestibular receptor system. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Vestibular Symptoms in Factory Workers Subjected to Noise for a Long Period

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G Raghunath

2012-06-01

Full Text Available Background: Noise can cause permanent or temporary hearing loss. High levels of noise may stimulate the vestibular system and thereby cause disturbances in the balancing mechanism. Objective: To determine the effect of long-term exposure to occupational noise on the vestibular system. Methods: A dizziness questionnaire was administered to 20 factory workers who were exposed to occupational noise for more than 10 years. The results were compared with 2 control groups. The control group 1 consisted of 20 people who had similar physical activity during work but were not exposed to high level of noise. Control group 2 consisted of 20 students never exposed to hazardous noise. Results: There was significant difference between the experimental group and the 2 control groups in terms of frequency of vestibular symptoms. However, most of the symptoms were subtle in nature. Tinnitus was significantly (p<0.05 more frequent in the experimental group than the 2 control groups. Conclusions: Long-term exposure to noise may cause vestibular symptoms before clinically detectable hearing loss. The symptoms are subtle for which they are mostly neglected; the symptoms do not affect the functional ability of workers.

Functional changes at the preferred retinal locus in subjects with bilateral central vision loss.

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Krishnan, Arun Kumar; Bedell, Harold E

2018-01-01

Subjects with bilateral central vision loss (CVL) use a retinal region called the preferred retinal locus (PRL) for performing various visual tasks. We probed the fixation PRL in individuals with bilateral macular disease, including age-related macular degeneration (AMD) and Stargardt disease (STGD), for localized sensitivity deficits. Three letter words at the critical print size were presented in the NIDEK MP-1 microperimeter to determine the fixation PRL and its radial retinal eccentricity from the residual fovea in 29 subjects with bilateral CVL. Fixation stability was defined as the median bivariate contour ellipse area (BCEA) from 3 fixation assessments. A standard 10-2 grid (68 locations, 2° apart) was used to determine central retinal sensitivity for Goldmann size II test spots. Baseline and follow-up supra-threshold screening of the fixation PRL for localized sensitivity deficits was performed using high density (0.2° or 0.3° apart) 0 dB Goldmann size II test spots. Custom MATLAB code and a dual bootstrapping algorithm were used to register test-spot locations from the baseline and follow-up tests. Locations where the 0 dB test spots were not seen on either test were labeled as micro-scotomas (MSs). Median BCEA correlated poorly with the radial eccentricity of the fixation PRL. Mean (±SD) sensitivity around the PRL from 10-2 testing was 4.93 ± 4.73 dB. The average percentage of MSs was similar for patients with AMD (25.4%), STGD (20.3%), and other etiologies of CVL (27.1%). The fixation PRL in subjects with bilateral CVL frequently includes local regions of sensitivity loss.

Interactive wiimote gaze stabilization exercise training system for patients with vestibular hypofunction.

Science.gov (United States)

Chen, Po-Yin; Hsieh, Wan-Ling; Wei, Shun-Hwa; Kao, Chung-Lan

2012-10-09

Peripheral vestibular hypofunction is a major cause of dizziness. When complicated with postural imbalance, this condition can lead to an increased incidence of falls. In traditional clinical practice, gaze stabilization exercise is commonly used to rehabilitate patients. In this study, we established a computer-aided vestibular rehabilitation system by coupling infrared LEDs to an infrared receiver. This system enabled the subjects' head-turning actions to be quantified, and the training was performed using vestibular exercise combined with computer games and interactive video games that simulate daily life activities. Three unilateral and one bilateral vestibular hypofunction patients volunteered to participate in this study. The participants received 30 minutes of computer-aided vestibular rehabilitation training 2 days per week for 6 weeks. Pre-training and post-training assessments were completed, and a follow-up assessment was completed 1 month after the end of the training period. After 6 weeks of training, significant improvements in balance and dynamic visual acuity (DVA) were observed in the four participants. Self-reports of dizziness, anxiety and depressed mood all decreased significantly. Significant improvements in self-confidence and physical performance were also observed. The effectiveness of this training was maintained for at least 1 month after the end of the training period. Real-time monitoring of training performance can be achieved using this rehabilitation platform. Patients demonstrated a reduction in dizziness symptoms after 6 weeks of training with this short-term interactive game approach. This treatment paradigm also improved the patients' balance function. This system could provide a convenient, safe and affordable treatment option for clinical practitioners.

Vestibular-Somatosensory Convergence in Head Movement Control During Locomotion after Long-Duration Space Flight

Science.gov (United States)

Mulavara, Ajitkumar; Ruttley, Tara; Cohen, Helen; Peters, Brian; Miller, Chris; Brady, Rachel; Merkle, Lauren; Bloomberg, Jacob

2010-01-01

Exposure to the microgravity conditions of space flight induces adaptive modification in the control of vestibular-mediated reflexive head movement during locomotion after space flight. Space flight causes astronauts to be exposed to somatosensory adaptation in both the vestibular and body load-sensing (BLS) systems. The goal of these studies was to examine the contributions of vestibular and BLS-mediated somatosensory influences on head movement control during locomotion after long-duration space flight. Subjects were asked to walk on a treadmill driven at 1.8 m/s while performing a visual acuity task. Data were collected using the same testing protocol from three independent subject groups; 1) normal subjects before and after exposure to 30 minutes of 40% bodyweight unloaded treadmill walking, 2) bilateral labyrinthine deficient (LD) patients and 3) astronauts who performed the protocol before and after long duration space flight. Motion data from head and trunk segmental motion data were obtained to calculate the angular head pitch (HP) movements during walking trials while subjects performed the visual task, to estimate the contributions of vestibular reflexive mechanisms in HP movements. Results showed that exposure to unloaded locomotion caused a significant increase in HP movements, whereas in the LD patients the HP movements were significantly decreased. Astronaut subjects results showed a heterogeneous response of both increases and decreases in the amplitude of HP movement. We infer that BLS-mediated somatosensory input centrally modulates vestibular input and can adaptively modify head-movement control during locomotion. Thus, space flight may cause a central adaptation mediated by the converging vestibular and body load-sensing somatosensory systems.

Current concepts and future approaches to vestibular rehabilitation.

Science.gov (United States)

Tjernström, Fredrik; Zur, Oz; Jahn, Klaus

2016-04-01

Over the last decades methods of vestibular rehabilitation to enhance adaptation to vestibular loss, habituation to changing sensory conditions, and sensory reweighting in the compensation process have been developed. However, the use of these techniques still depends to a large part on the educational background of the therapist. Individualized assessment of deficits and specific therapeutic programs for different disorders are sparse. Currently, vestibular rehabilitation is often used in an unspecific way in dizzy patients irrespective of the clinical findings. When predicting the future of vestibular rehabilitation, it is tempting to foretell advances in technology for assessment and treatment only, but the current intense exchange between clinicians and basic scientists also predicts advances in truly understanding the complex interactions between the peripheral senses and central adaptation mechanisms. More research is needed to develop reliable techniques to measure sensory dependence and to learn how this knowledge can be best used--by playing off the patient's sensory strength or working on the weakness. To be able using the emerging concepts, the neuro-otological community must strive to educate physicians, physiotherapists and nurses to perform the correct examinations for assessment of individual deficits and to look for factors that might impede rehabilitation.

Modified Willet′s appliance for bilateral loss of multiple deciduous molars: A case report

OpenAIRE

Dhindsa A; Pandit I

2008-01-01

No other factor plays a more significant role in preventive and interceptive dentistry than the preservation of deciduous dentition till its normal time of exfoliation. Premature loss of a deciduous tooth or a group of teeth might lead to wide range of implications. When the deciduous second molar is lost before the eruption of first permanent molar, intra-alveolar type of space maintainer is indicated. But in cases of bilateral loss of these teeth the conventional design generally poses a va...

Persistent conductive or mixed hearing loss after the placement of tympanostomy tubes.

Science.gov (United States)

Whittemore, Kenneth R; Dornan, Briana K; Lally, Tara; Dargie, Jenna M

2012-10-01

Described is a case series of clinical findings in children with persistent conductive or mixed hearing loss following tympanostomy tube placement for serous otitis media. Retrospective chart review. Tertiary pediatric hospital. Medical records of thirty-nine children who were referred for either conductive or mixed hearing loss post-tympanostomy tube placement were reviewed for clinical histories, physical examinations, audiological evaluations, diagnostic studies, consultations, and surgical findings. Approval was obtained from the Boston Children's Hospital Institutional Review Board. Causes of hearing loss included ossicular abnormalities, cochlear abnormalities, 'third window' effects, cholesteatomas, genetic syndromes, and unknown causes. In four patients with isolated mild low-frequency conductive hearing loss, the cause was the presence of functional tubes. All patients diagnosed with a genetic syndrome had bilateral hearing loss. Patients with mixed hearing loss were diagnosed with cochlear abnormalities, 'third window' effects, or genetic syndromes. Computed tomography led to diagnosis in sixteen of twenty-five patients. Vestibular-evoked myogenic potential testing suggested a diagnosis in three of four patients. In children with persistent hearing loss following tympanostomy tube placement, identifying the laterality and type of hearing loss appears to be of importance in diagnosis. Patients with bilateral hearing loss should be considered for genetic testing, given the possibility of a syndrome. Patients identified with a mixed hearing loss should be evaluated for inner ear anomalies. Patients with mild, low-frequency hearing losses should be monitored audiologically and investigated further only if the hearing loss progresses and/or there is no resolution following tube extrusion. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The Relationship between Vestibular Function and Topographical Memory in Older Adults

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Fred Henry Previc

2014-06-01

Full Text Available Research during the past two decades has demonstrated an important role of the vestibular system in topographical orientation and memory and the network of neural structures associated with them. Almost all of the supporting data have come from animal or human clinical studies, however. The purpose of the present study was to investigate the link between vestibular function and topographical memory in normal elderly humans. Twenty-five participants aged 70 to 85 years who scored from mildly impaired to normal on the Montreal Cognitive Assessment received three topographical memory tests: the Camden Topographical Recognition Memory Test (CTMRT, a computerized topographical mental rotation test (TMRT, and a virtual pond maze (VPM. They also received six vestibular or oculomotor tests: optokinetic nystagmus (OKN, visual pursuit (VP, actively generated vestibulo-ocular reflex (VOR, the sensory orientation test (SOT for posture, and two measures of rotational memory (error in degrees, or RMº, and correct directional recognition, or RM→. The only significant bivariate correlations were among the three vestibular measures primarily assessing horizontal canal function (VOR, RMº, and RM→. A multiple regression analysis showed significant relationships between vestibular and demographic predictors and both the TMRT (R=.78 and VPM (R=.66 measures. The significant relationship between the vestibular and topographical memory measures supports the theory that vestibular loss may contribute to topographical memory impairment in the elderly.

Bilateral idiopathic optic perineuritis with severe vision loss: A case report

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Wee-Min Teh

2015-07-01

Full Text Available Optic perineuritis is an orbital inflammatory disorder that is either idiopathic or secondary to other conditions such as infection or systemic inflammatory disorders. This condition is very similar to demyelinating optic neuritis, but certain features of the history and magnetic resonance imaging findings are characteristic for and aid in the diagnosis of optic perineuritis. Vision loss varies greatly, from minimal clouding of vision up to only light perception. We report a case of a 44-year-old female with idiopathic bilateral optic perineuritis with vision loss of up to no light perception in both eyes. Radio imaging studies were typical of optic perineuritis and she was started on systemic corticosteroids. She responded very well to steroid therapy and achieved nearly complete visual recovery. There had been no relapse despite cessation of therapy.

Vestibular Rehabilitation in a Patient with Whiplash-associated Disorders

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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.

A novel single-step surgical technique for vestibular deepening using laser in conjunction with periodontal flap surgery

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Ashu Bhardwaj

2016-01-01

Full Text Available Moderate-to-severe chronic periodontitis results in clinical loss of attachment, reduced width of attached gingiva (AG, periodontal pockets beyond mucogingival junction (MGJ, gingival recession, loss of alveolar bone, and decreased vestibular depth (VD. The encroachment of frenal and muscle attachments on marginal gingiva increases the rate of progression of periodontal pockets, prevents healing, and causes their recurrence after therapy. Loss of VD and AG associated with continuous progression of pocket formation and bone loss requires two-stage surgical procedures. In this article, one-stage surgical procedure is being described for the first time, to treat the periodontal pockets extending beyond the MGJ by periodontal flap surgery along with vestibular deepening with diode laser to increase the AG. One-step surgical technique is illustrated whereby pocket therapy with reconstruction of lost periodontal tissues can be done along with gingival augmentation by vestibular deepening.

A influência da perda bilateral do primeiro molar inferior permanente na morfologia dentofacial: um estudo cefalométrico The influence of bilateral lower first permanent molar loss on dentofacial morfology: a cephalometric study

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David Normando

2010-12-01

Full Text Available OBJETIVO: avaliar as alterações cefalométricas em pacientes com perda bilateral do primeiro molar inferior permanente. MÉTODOS: foram analisadas 68 telerradiografias laterais de pacientes de consultórios particulares. A amostra foi dividida em dois grupos pareados quanto ao sexo e idade - 34 indivíduos sem perdas (grupo controle e 34 com perda bilateral do primeiro molar inferior permanente (grupo com perda. Foram excluídos da amostra pacientes que haviam perdido outros dentes que não o primeiro molar inferior, casos de agenesia e pacientes com menos de 16 anos de idade. Buscou-se avaliar somente indivíduos que tivessem relatado a perda há pelo menos 5 anos. RESULTADOS: demonstraram que a perda bilateral do primeiro molar inferior permanente leva ao suave fechamento do ângulo GnSN (P=0,05, um giro anti-horário do plano oclusal (P=0,0001, uma suave diminuição da altura facial anteroinferior (P=0,05, uma acentuada inclinação lingual (P=0,04 e retrusão dos incisivos inferiores (P=0,03. Por outro lado, a perda bilateral do primeiro molar inferior permanente não foi capaz de influenciar a relação maxilomandibular no sentido anteroposterior (P=0,21, a quantidade de mento (P=0,45, a inclinação dos incisivos superiores (P=0,12 e a posição anteroposterior dos incisivos superiores (P=0,46. CONCLUSÃO: a perda bilateral dos primeiros molares inferiores é capaz de produzir alterações marcantes no posicionamento dos incisivos inferiores e no plano oclusal, além de uma suave redução vertical da faceOBJECTIVE: To evaluate cephalometric changes in patients after bilateral loss of lower first permanent molar teeth. METHODS: Sixty-eight lateral radiographs of patients from private practices were analyzed. The sample was divided into two groups matched for age and gender: 34 individuals without loss (control group and 34 presenting with bilateral loss of lower first permanent molar teeth (loss group. Patients who had lost teeth other

Neurophysiology of vestibular rehabilitation.

Science.gov (United States)

Hain, Timothy C

2011-01-01

The vestibular system is a sophisticated human control system. Accurate processing of sensory input about rapid head and postural motion is critical. Not surprisingly, the body uses multiple, partially redundant sensory inputs and motor outputs, combined with a very competent central repair capability. The system as a whole can adapt to substantial peripheral vestibular dysfunction. The Achilles' heel of the vestibular system is a relative inability to repair central vestibular dysfunction.

Neurophysiology of vestibular rehabilitation

OpenAIRE

Hain Timothy, C.

2011-01-01

The vestibular system is a sophisticated human control system. Accurate processing of sensory input about rapid head and postural motion is critical. Not surprisingly, the body uses multiple, partially redundant sensory inputs and motor outputs, combined with a very competent central repair capability. The system as a whole can adapt to substantial peripheral vestibular dysfunction. The Achilles' heel of the vestibular system is a relative inability to repair central vestibular dysfunction.

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....

Primary Sjogren’s Syndrome Presented with Sensory Ataxia Associated with Bilateral Hearing Loss and Dementia

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Madjdinasab Nastaran

2009-10-01

Full Text Available Primary Sjorgen syndrome is one of the commonest autoimmune diseases with characteristic of involvement of lachrymal and salivary glands, but other organ involvements as peripheral and central nervous system are also possible. The reported case is a 23 year old lady presented with progressive sensory ataxia and weakness of four limbs, bilateral sensory hearing loss and cognitive impairment with minimental score equal to 15/30 since one year prior to admission with associated bilateral central corneal opacity, dry mouth and dry eyes. Electro physiologic studies showed sensory motor axonal polyneuropathy . A biopsy of sural nerve and salivary glands of lower lip showed lymphocytic infiltration. Serologic evidence showed positive Anti Ro (SS-B, negative HCV and HIV antibody, thereafter the diagnosis was confirmed and according to this diagnosis she received high dose of intravenous methyl prednisolon then both hearing loss and cognitive impairment improved partially (minimental score 21/30 . At last, she underwent plasmapheresis and her sensory ataxia improved greatly.

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.

Interactive wiimote gaze stabilization exercise training system for patients with vestibular hypofunction

Directory of Open Access Journals (Sweden)

Chen Po-Yin

2012-10-01

Full Text Available Abstract Background Peripheral vestibular hypofunction is a major cause of dizziness. When complicated with postural imbalance, this condition can lead to an increased incidence of falls. In traditional clinical practice, gaze stabilization exercise is commonly used to rehabilitate patients. In this study, we established a computer-aided vestibular rehabilitation system by coupling infrared LEDs to an infrared receiver. This system enabled the subjects’ head-turning actions to be quantified, and the training was performed using vestibular exercise combined with computer games and interactive video games that simulate daily life activities. Methods Three unilateral and one bilateral vestibular hypofunction patients volunteered to participate in this study. The participants received 30 minutes of computer-aided vestibular rehabilitation training 2 days per week for 6 weeks. Pre-training and post-training assessments were completed, and a follow-up assessment was completed 1 month after the end of the training period. Results After 6 weeks of training, significant improvements in balance and dynamic visual acuity (DVA were observed in the four participants. Self-reports of dizziness, anxiety and depressed mood all decreased significantly. Significant improvements in self-confidence and physical performance were also observed. The effectiveness of this training was maintained for at least 1 month after the end of the training period. Conclusion Real-time monitoring of training performance can be achieved using this rehabilitation platform. Patients demonstrated a reduction in dizziness symptoms after 6 weeks of training with this short-term interactive game approach. This treatment paradigm also improved the patients’ balance function. This system could provide a convenient, safe and affordable treatment option for clinical practitioners.

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

Bilateral sudden sensorineural hearing loss as a first symptom of infective endocarditis: two case reports.

Science.gov (United States)

Chroni, M; Prappa, E; Kokkevi, I

2018-04-01

Septic emboli are an unusual cause of sudden sensorineural hearing loss, for which few reports exist in the literature. This paper presents two cases of sudden sensorineural hearing loss, initially considered as idiopathic, but which were caused by septic emboli. Hearing loss in these cases was bilateral, sequential and total. The first patient had mild fever one week prior to their presentation with sudden sensorineural hearing loss; the other patient had no additional symptoms at presentation. These patients were later diagnosed with infective endocarditis, at two and seven months following the sudden sensorineural hearing loss respectively, showing that septic emboli had been the cause of sudden sensorineural hearing loss. Septic emboli should be considered as a possible cause of sudden sensorineural hearing loss in cases of total hearing loss. This form of hearing loss should prompt the otolaryngologist to further investigate for infective endocarditis.

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.

Drug therapy for peripheral vestibular vertigo

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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.

Differential effects of galvanic vestibular stimulation on arm position sense in right- vs. left-handers.

Science.gov (United States)

Schmidt, Lena; Artinger, Frank; Stumpf, Oliver; Kerkhoff, Georg

2013-04-01

The human brain is organized asymmetrically in two hemispheres with different functional specializations. Left- and right-handers differ in many functional capacities and their anatomical representations. Right-handers often show a stronger functional lateralization than left-handers, the latter showing a more bilateral, symmetrical brain organization. Recent functional imaging evidence shows a different lateralization of the cortical vestibular system towards the side of the preferred hand in left- vs. right-handers as well. Since the vestibular system is involved in somatosensory processing and the coding of body position, vestibular stimulation should affect such capacities differentially in left- vs. right-handers. In the present, sham-stimulation-controlled study we explored this hypothesis by studying the effects of galvanic vestibular stimulation (GVS) on proprioception in both forearms in left- and right-handers. Horizontal arm position sense (APS) was measured with an opto-electronic device. Second, the polarity-specific online- and after-effects of subsensory, bipolar GVS on APS were investigated in different sessions separately for both forearms. At baseline, both groups did not differ in their unsigned errors for both arms. However, right-handers showed significant directional errors in APS of both arms towards their own body. Right-cathodal/left-anodal GVS, resulting in right vestibular cortex activation, significantly deteriorated left APS in right-handers, but had no detectable effect on APS in left-handers in either arm. These findings are compatible with a right-hemisphere dominance for vestibular functions in right-handers and a differential vestibular organization in left-handers that compensates for the disturbing effects of GVS on APS. Moreover, our results show superior arm proprioception in left-handers in both forearms. Copyright © 2013 Elsevier Ltd. All rights reserved.

Gamma Knife radiosurgery for vestibular schwannoma: case report and review of the literature.

Science.gov (United States)

Arthurs, Benjamin J; Lamoreaux, Wayne T; Giddings, Neil A; Fairbanks, Robert K; Mackay, Alexander R; Demakas, John J; Cooke, Barton S; Lee, Christopher M

2009-12-18

Vestibular schwannomas, also called acoustic neuromas, are benign tumors of the vestibulocochlear nerve. Patients with these tumours almost always present with signs of hearing loss, and many also experience tinnitus, vertigo, and equilibrium problems. Following diagnosis with contrast enhanced MRI, patients may choose to observe the tumour with subsequent scans or seek active treatment in the form of microsurgery, radiosurgery, or radiotherapy. Unfortunately, definitive guidelines for treating vestibular schwannomas are lacking, because of insufficient evidence comparing the outcomes of therapeutic modalities.We present a contemporary case report, describing the finding of a vestibular schwannoma in a patient who presented with dizziness and a "clicking" sensation in the ear, but no hearing deficit. Audible clicking is a symptom that, to our knowledge, has not been associated with vestibular schwannoma in the literature. We discuss the diagnosis and patient's decision-making process, which led to treatment with Gamma Knife radiosurgery. Treatment resulted in an excellent radiographic response and complete hearing preservation. This case highlights an atypical presentation of vestibular schwannoma, associated with audible "clicks" and normal hearing. We also provide a concise review of the available literature on modern vestibular schwannoma treatment, which may be useful in guiding treatment decisions.

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.

The Skull Vibration-Induced Nystagmus Test of Vestibular Function—A Review

Science.gov (United States)

Dumas, Georges; Curthoys, Ian S.; Lion, Alexis; Perrin, Philippe; Schmerber, Sébastien

2017-01-01

A 100-Hz bone-conducted vibration applied to either mastoid induces instantaneously a predominantly horizontal nystagmus, with quick phases beating away from the affected side in patients with a unilateral vestibular loss (UVL). The same stimulus in healthy asymptomatic subjects has little or no effect. This is skull vibration-induced nystagmus (SVIN), and it is a useful, simple, non-invasive, robust indicator of asymmetry of vestibular function and the side of the vestibular loss. The nystagmus is precisely stimulus-locked: it starts with stimulation onset and stops at stimulation offset, with no post-stimulation reversal. It is sustained during long stimulus durations; it is reproducible; it beats in the same direction irrespective of which mastoid is stimulated; it shows little or no habituation; and it is permanent—even well-compensated UVL patients show SVIN. A SVIN is observed under Frenzel goggles or videonystagmoscopy and recorded under videonystagmography in absence of visual-fixation and strong sedative drugs. Stimulus frequency, location, and intensity modify the results, and a large variability in skull morphology between people can modify the stimulus. SVIN to 100 Hz mastoid stimulation is a robust response. We describe the optimum method of stimulation on the basis of the literature data and testing more than 18,500 patients. Recent neural evidence clarifies which vestibular receptors are stimulated, how they cause the nystagmus, and why the same vibration in patients with semicircular canal dehiscence (SCD) causes a nystagmus beating toward the affected ear. This review focuses not only on the optimal parameters of the stimulus and response of UVL and SCD patients but also shows how other vestibular dysfunctions affect SVIN. We conclude that the presence of SVIN is a useful indicator of the asymmetry of vestibular function between the two ears, but in order to identify which is the affected ear, other information and careful clinical judgment are

The effect of cochlear implantation on tinnitus in patients with bilateral hearing loss : A systematic review

NARCIS (Netherlands)

Ramakers, Geerte G J; van Zon, Alice; Stegeman, Inge; Grolman, Wilko

2015-01-01

OBJECTIVES: To present an overview of the effect of cochlear implantation on tinnitus in adults with bilateral sensorineural hearing loss. DATA SOURCES: PubMed, Cochrane Library, CINAHL, and Embase databases were searched for articles from database inception up to January 13, 2015. METHODS: A

Partial Aminoglycoside Lesions in Vestibular Epithelia Reveal Broad Sensory Dysfunction Associated with Modest Hair Cell Loss and Afferent Calyx Retraction.

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Sultemeier, David R; Hoffman, Larry F

2017-01-01

Although the effects of aminoglycoside antibiotics on hair cells have been investigated for decades, their influences on the dendrites of primary afferent neurons have not been widely studied. This is undoubtedly due to the difficulty in disassociating pathology to dendritic processes from that resulting from loss of the presynaptic hair cell. This was overcome in the present investigation through development of a preparation using Chinchilla laniger that enabled direct perilymphatic infusion. Through this strategy we unmasked gentamicin's potential effects on afferent calyces. The pathophysiology of the vestibular neuroepithelia after post-administration durations of 0.5 through 6 months was assessed using single-neuron electrophysiology, immunohistochemistry, and confocal microscopy. Hair cell densities within cristae central zones (0.5-, 1-, 2-, and 6-months) and utricle peri- and extrastriola (6-months) regions were determined, and damage to calretinin-immunoreactive calyces was quantified. Gentamicin-induced hair cell loss exhibited a profile that reflected elimination of a most-sensitive group by 0.5-months post-administration (18.2%), followed by loss of a second group (20.6%) over the subsequent 5.5 months. The total hair cell loss with this gentamicin dose (approximately 38.8%) was less than the estimated fraction of type I hair cells in the chinchilla's crista central zone (approximately 60%), indicating that viable type I hair cells remained. Extensive lesions to afferent calyces were observed at 0.5-months, though stimulus-evoked modulation was intact at this post-administration time. Widespread compromise to calyx morphology and severe attenuation of stimulus-evoked afferent discharge modulation was found at 1 month post-administration, a condition that persisted in preparations examined through the 6-month post-administration interval. Spontaneous discharge was robust at all post-administration intervals. All calretinin-positive calyces had retracted

Loss aversion is associated with bilateral insula volume. A voxel based morphometry study.

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Markett, S; Heeren, G; Montag, C; Weber, B; Reuter, M

2016-04-21

Loss aversion is a decision bias, reflecting a greater sensitivity to losses than to gains in a decision situation. Recent neuroscientific research has shown that mesocorticolimbic structures like ventromedial prefrontal cortex and the ventral striatum constitute a bidirectional neural system that processes gains and losses and exhibits a neural basis of loss aversion. On a functional and structural level, the amygdala and insula also seem to play an important role in the processing of loss averse behavior. By applying voxel-based morphometry to structural brain images in N=41 healthy participants, the current study provides further evidence for the relationship of brain structure and loss aversion. The results show a negative correlation of gray matter volume in bilateral posterior insula as well as left medial frontal gyrus with individual loss aversion. Hence, higher loss aversion is associated with lower gray matter volume in these brain areas. Both structures have been discussed to play important roles in the brain's salience network, where the posterior insula is involved in interoception and the detection of salience. The medial frontal gyrus might impact decision making through its dense connections with the anterior cingulate cortex. A possible explanation for the present finding is that structural differences in these regions alter the processing of losses and salience, possibly biasing decision making towards avoidance of negative outcomes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Comparison of Postural Responses to Galvanic Vestibular Stimulation between Pilots and the General Populace

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Yang Yang

2015-01-01

Full Text Available Galvanic vestibular stimulation (GVS can be used to study the body’s response to vestibular stimuli. This study aimed to investigate whether postural responses to GVS were different between pilots and the general populace. Bilateral bipolar GVS was applied with a constant-current profile to 12 pilots and 12 control subjects via two electrodes placed over the mastoid processes. Both GVS threshold and the center of pressure’s trajectory (COP’s trajectory were measured. Position variability of COP during spontaneous body sway and peak displacement of COP during GVS-induced body sway were calculated in the medial-lateral direction. Spontaneous body sway was slight for all subjects, and there was no significant difference in the value of COP position variability between the pilots and controls. Both the GVS threshold and magnitude of GVS-induced body deviation were similar for different GVS polarities. GVS thresholds were similar between the two groups, but the magnitude of GVS-induced body deviation in the controls was significantly larger than that in the pilots. The pilots showed less GVS-induced body deviation, meaning that pilots may have a stronger ability to suppress vestibular illusions.

Effect of transcranial direct current stimulation on vestibular-ocular and vestibulo-perceptual thresholds.

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Kyriakareli, Artemis; Cousins, Sian; Pettorossi, Vito E; Bronstein, Adolfo M

2013-10-02

Transcranial direct current stimulation (tDCS) was used in 17 normal individuals to modulate vestibulo-ocular reflex (VOR) and self-motion perception rotational thresholds. The electrodes were applied over the temporoparietal junction bilaterally. Both vestibular nystagmic and perceptual thresholds were increased during as well as after tDCS stimulation. Body rotation was labeled as ipsilateral or contralateral to the anode side, but no difference was observed depending on the direction of rotation or hemisphere polarity. Threshold increase during tDCS was greater for VOR than for motion perception. 'Sham' stimulation had no effect on thresholds. We conclude that tDCS produces an immediate and sustained depression of cortical regions controlling VOR and movement perception. Temporoparietal areas appear to be involved in vestibular threshold modulation but the differential effects observed between VOR and perception suggest a partial dissociation between cortical processing of reflexive and perceptual responses.

Gamma Knife radiosurgery for vestibular schwannoma: case report and review of the literature

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Fairbanks Robert K

2009-12-01

Full Text Available Abstract Vestibular schwannomas, also called acoustic neuromas, are benign tumors of the vestibulocochlear nerve. Patients with these tumours almost always present with signs of hearing loss, and many also experience tinnitus, vertigo, and equilibrium problems. Following diagnosis with contrast enhanced MRI, patients may choose to observe the tumour with subsequent scans or seek active treatment in the form of microsurgery, radiosurgery, or radiotherapy. Unfortunately, definitive guidelines for treating vestibular schwannomas are lacking, because of insufficient evidence comparing the outcomes of therapeutic modalities. We present a contemporary case report, describing the finding of a vestibular schwannoma in a patient who presented with dizziness and a "clicking" sensation in the ear, but no hearing deficit. Audible clicking is a symptom that, to our knowledge, has not been associated with vestibular schwannoma in the literature. We discuss the diagnosis and patient's decision-making process, which led to treatment with Gamma Knife radiosurgery. Treatment resulted in an excellent radiographic response and complete hearing preservation. This case highlights an atypical presentation of vestibular schwannoma, associated with audible "clicks" and normal hearing. We also provide a concise review of the available literature on modern vestibular schwannoma treatment, which may be useful in guiding treatment decisions.

A study on vestibular-evoked myogenic potentials via galvanic vestibular stimulation in normal people

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Ying Cheng

2018-03-01

Discussions: Galvanic vestibular stimulation could elicit biphasic EMG responses from SCM via the vestibular nerve but not from the otolith organs. Galvanic stimulation together with air conducted sound (ACS or bone conducted vibration (BCV can elicit VEMPs and may enable the differentiation of retrolabyrinthine lesions from labyrinthine lesions in vestibular system.

Recovery from Spatial Neglect with Intra- and Transhemispheric Functional Connectivity Changes in Vestibular and Visual Cortex Areas—A Case Study

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Julian Conrad

2018-03-01

Full Text Available ObjectiveVestibular signals are involved in higher cortical functions like spatial orientation and its disorders. Vestibular dysfunction contributes, for example, to spatial neglect which can be transiently improved by caloric stimulation. The exact roles and mechanisms of the vestibular and visual systems for the recovery of neglect are not yet known.MethodsResting-state functional connectivity (fc magnetic resonance imaging was recorded in a patient with hemispatial neglect during the acute phase and after recovery 6 months later following a right middle cerebral artery infarction before and after caloric vestibular stimulation. Seeds in the vestibular [parietal operculum (OP2], the parietal [posterior parietal cortex (PPC; 7A, hIP3], and the visual cortex (VC were used for the analysis.ResultsDuring the acute stage after caloric stimulation the fc of the right OP2 to the left OP2, the anterior cingulum, and the para/hippocampus was increased bilaterally (i.e., the vestibular network, while the interhemispheric fc was reduced between homologous regions in the VC. After 6 months, similar fc increases in the vestibular network were found without stimulation. In addition, fc increases of the OP2 to the PPC and the VC were seen; interhemispherically this was true for both PPCs and for the right PPC to both VCs.ConclusionImprovement of neglect after caloric stimulation in the acute phase was associated with increased fc of vestibular cortex areas in both hemispheres to the para-hippocampus and the dorsal anterior cingulum, but simultaneously with reduced interhemispheric VC connectivity. This disclosed a, to some extent, similar but also distinct short-term mechanism (vestibular stimulation of an improvement of spatial orientation compared to the long-term recovery of neglect.

Enhancing vestibular function in the elderly with imperceptible electrical stimulation.

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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.

Age-Related Neurochemical Changes in the Vestibular Nuclei

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Paul eSmith

2016-03-01

Full Text Available There is evidence that the normal aging process is associated with impaired vestibulo-ocular (VOR and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa’s ganglion and the vestibular nucleus complex (VNC, it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarises and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics.

Age-Related Neurochemical Changes in the Vestibular Nuclei.

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Smith, Paul F

2016-01-01

There is evidence that the normal aging process is associated with impaired vestibulo-ocular reflexes (VOR) and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa's ganglion and the vestibular nucleus complex (VNC), it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarizes and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics.

Vestibular migraine: who is the patient?

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Colombo, Bruno; Teggi, Roberto

2017-05-01

Vestibular migraine has been classified as a specific entity in which vestibular symptomatology is defined as part of the migrainous disorder. New and appropriate diagnostic criteria have been proposed by the Barany and International Headache Societies. The diagnosis of vestibular migraine mainly depends on the patient history. The NIVE project is a prospectic multicentric study on vestibular migraine. The aim of this project is to evaluate demographics, epidemiology, clinical manifestations of migraine and vertigo in a large cohort of Caucasian patients affected by vestibular migraine.

[From gene to disease; genetic causes of hearing loss and visual impairment sometimes accompanied by vestibular problems (Usher syndrome)].

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Pennings, R J E; Kremer, H; Deutman, A F; Kimberling, W J; Cremers, C W R J

2002-12-07

Usher syndrome is an autosomal recessively inherited disease, characterised by sensorineural hearing loss, tapetoretinal degeneration and in some cases vestibular problems. Based on the clinical heterogeneity, the disease can be classified into three clinical types (I, II and III), which have their own genetic subtypes (Usher 1A-Usher IG, Usher 2A-Usher 2C and Usher 3). The majority of the Usher type I cases are caused by mutations in the MYO7A gene (Usher 1B) while mutations in the USH2A gene (Usher 2A) are the cause of most cases of type II. Usher syndrome type III, caused by mutations in the USH3 gene, is frequently seen only in Finland.

Characterizing human vestibular sensory epithelia for experimental studies: new hair bundles on old tissue and implications for therapeutic interventions in ageing.

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Taylor, Ruth R; Jagger, Daniel J; Saeed, Shakeel R; Axon, Patrick; Donnelly, Neil; Tysome, James; Moffatt, David; Irving, Richard; Monksfield, Peter; Coulson, Chris; Freeman, Simon R; Lloyd, Simon K; Forge, Andrew

2015-06-01

Balance disequilibrium is a significant contributor to falls in the elderly. The most common cause of balance dysfunction is loss of sensory cells from the vestibular sensory epithelia of the inner ear. However, inaccessibility of inner ear tissue in humans severely restricts possibilities for experimental manipulation to develop therapies to ameliorate this loss. We provide a structural and functional analysis of human vestibular sensory epithelia harvested at trans-labyrinthine surgery. We demonstrate the viability of the tissue and labeling with specific markers of hair cell function and of ion homeostasis in the epithelium. Samples obtained from the oldest patients revealed a significant loss of hair cells across the tissue surface, but we found immature hair bundles present in epithelia harvested from patients >60 years of age. These results suggest that the environment of the human vestibular sensory epithelium could be responsive to stimulation of developmental pathways to enhance hair cell regeneration, as has been demonstrated successfully in the vestibular organs of adult mice. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Electric Current Transmission Through Tissues of the Vestibular Labyrinth of a Patient: Perfection of the Vestibular Implant

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Demkin, V. P.; Shchetinin, P. P.; Melnichuk, S. V.; Kingma, H.; Van de Berg, R.; Pleshkov, M. O.; Starkov, D. N.

2018-03-01

An electric model of current transmission through tissues of the vestibular labyrinth of a patient is suggested. To stimulate directly the vestibular nerve in surgical operation, terminations of the electrodes are implanted through the bone tissue of the labyrinth into the perilymph in the vicinity of the vestibular nerve. The biological tissue of the vestibular labyrinth surrounding the electrodes and having heterogeneous composition possesses conductive and dielectric properties. Thus, when a current pulse from the vestibular implant is applied to one of the electrodes, conductive disturbance currents may arise between the electrodes and the vestibular nerves that can significantly deteriorate the direct signal quality. To study such signals and to compensate for the conductive disturbance currents, an equivalent electric circuit with actual electric impedance properties of tissues of the vestibular system is suggested, and the time parameters of the conductive disturbance current transmission are calculated. It is demonstrated that these parameters can reach large values. The suggested electric model and the results of calculations can be used for perfection of the vestibular implant.

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

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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.

Central vestibular dysfunction in an otorhinolaryngological vestibular unit: incidence and diagnostic strategy.

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Mostafa, Badr E; Kahky, Ayman O El; Kader, Hisham M Abdel; Rizk, Michael

2014-07-01

Introduction Vertigo can be due to a variety of central and peripheral causes. The relative incidence of central causes is underestimated. This may have an important impact of the patients' management and prognosis. Objective The objective of this work is to determine the incidence of central vestibular disorders in patients presenting to a vestibular unit in a tertiary referral academic center. It also aims at determining the best strategy to increase the diagnostic yield of the patients' visit. Methods This is a prospective observational study on 100 consecutive patients with symptoms suggestive of vestibular dysfunction. All patients completed a structured questionnaire and received bedside and vestibular examination and neuroimaging as required. Results There were 69 women and 31 men. Their ages ranged between 28 and 73 (mean 42.48 years). Provisional videonystagmography (VNG) results were: 40% benign paroxysmal positional vertigo (BPPV), 23% suspicious of central causes, 18% undiagnosed, 15% Meniere disease, and 4% vestibular neuronitis. Patients with an unclear diagnosis or central features (41) had magnetic resonance imaging (MRI) and Doppler studies. Combining data from history, VNG, and imaging studies, 23 patients (23%) were diagnosed as having a central vestibular lesion (10 with generalized ischemia/vertebra basilar insufficiency, 4 with multiple sclerosis, 4 with migraine vestibulopathy, 4 with phobic postural vertigo, and 1 with hyperventilation-induced nystagmus). Conclusions Combining a careful history with clinical examination, VNG, MRI, and Doppler studies decreases the number of undiagnosed cases and increases the detection of possible central lesions.

Central Vestibular Dysfunction in an Otorhinolaryngological Vestibular Unit: Incidence and Diagnostic Strategy

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Mostafa, Badr E.

2014-03-01

Full Text Available Introduction Vertigo can be due to a variety of central and peripheral causes. The relative incidence of central causes is underestimated. This may have an important impact of the patients' management and prognosis. Objective The objective of this work is to determine the incidence of central vestibular disorders in patients presenting to a vestibular unit in a tertiary referral academic center. It also aims at determining the best strategy to increase the diagnostic yield of the patients' visit. Methods This is a prospective observational study on 100 consecutive patients with symptoms suggestive of vestibular dysfunction. All patients completed a structured questionnaire and received bedside and vestibular examination and neuroimaging as required. Results There were 69 women and 31 men. Their ages ranged between 28 and 73 (mean 42.48 years. Provisional videonystagmography (VNG results were: 40% benign paroxysmal positional vertigo (BPPV, 23% suspicious of central causes, 18% undiagnosed, 15% Meniere disease, and 4% vestibular neuronitis. Patients with an unclear diagnosis or central features (41 had magnetic resonance imaging (MRI and Doppler studies. Combining data from history, VNG, and imaging studies, 23 patients (23% were diagnosed as having a central vestibular lesion (10 with generalized ischemia/vertebra basilar insufficiency, 4 with multiple sclerosis, 4 with migraine vestibulopathy, 4 with phobic postural vertigo, and 1 with hyperventilation-induced nystagmus. Conclusions Combining a careful history with clinical examination, VNG, MRI, and Doppler studies decreases the number of undiagnosed cases and increases the detection of possible central lesions.

Tranexamic acid for control of blood loss in bilateral total knee replacement in a single stage

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Mandeep S Dhillon

2011-01-01

Full Text Available Background: Tranexamic acid (TEA reduces blood loss and red cell transfusions in patients undergoing unilateral total knee arthroplasty (TKA. However, there is not much literature regarding the use of TEA in patients undergoing bilateral TKA in a single stage and the protocols for administration of TEA in such patients are ill-defined. Materials and Methods: We carried out a case control study evaluating the effect of TEA on postoperative hemoglobin (Hb, total drain output, and number of blood units transfused in 52 patients undergoing bilateral TKA in a single stage, and compared it with 56 matched controls who did not receive TEA. Two doses of TEA were administered in doses of 10 mg / kg each (slow intravenous (IV infusion, with the first dose given just before tourniquet release of the first knee and the second dose three hours after the first one. Results: A statistically significant reduction in the total drain output and requirement of allogenic blood transfusion in cases who received TEA, as compared to the controls was observed. The postoperative Hb and Hb at the time of discharge were found to be lower in the control group, and this result was found to be statistically significant. Conclusion: TEA administered in patients undergoing single stage bilateral TKA helped reduce total blood loss and decreased allogenic blood transfusion requirements. This might be particularly relevant, where facilities such as autologous reinfusion might not be available.

Characterizing human vestibular sensory epithelia for experimental studies: new hair bundles on old tissue and implications for therapeutic interventions in ageing

OpenAIRE

Taylor, Ruth R.; Jagger, Daniel J.; Saeed, Shakeel R.; Axon, Patrick; Donnelly, Neil; Tysome, James; Moffatt, David; Irving, Richard; Monksfield, Peter; Coulson, Chris; Freeman, Simon R.; Lloyd, Simon K.; Forge, Andrew

2015-01-01

Balance disequilibrium is a significant contributor to falls in the elderly. The most common cause of balance dysfunction is loss of sensory cells from the vestibular sensory epithelia of the inner ear. However, inaccessibility of inner ear tissue in humans severely restricts possibilities for experimental manipulation to develop therapies to ameliorate this loss. We provide a structural and functional analysis of human vestibular sensory epithelia harvested at trans-labyrinthine surgery. We ...

CONTRIBUTION OF THE AUDIOLOGICAL AND VESTIBULAR ASSESSMENT TO THE DIFFERENTIAL AND ETIOLOGICAL DIAGNOSIS OF PERIPHERIC VESTIBULAR SYNDROMES

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Loreta Ungureanu

2012-09-01

Full Text Available Scope of the study: Vestibular pathology is a complex one, requiring a minute clinical evaluation, as well as numerous paraclinical investigations. The present study analyzes the contribution of the modern methods of vestibular and auditive investigation to the diagnosis of dizziness. Materials and method: The results of the investigations performed on 84 patients with peripheric vestibular syndrome, on whom a complete audiological and vestibular assessment had been also made, have been retrospectively analyzed. Results: Anamnestic data and the results of evaluation permitted classification of peripheric vestibular pathology according to topo-lesional and etiological criteria. The most frequently diagnosed diseases were: benign paroxysmal positional vertigo, Ménière syndrome and vestibular neuronitis. Conclusions: Testing of the vestibulo-ocular and vestibulo-spinal reflexes through videonystagmoscopy and, respectively, computerized dynamic posturography, besides tonal vocal audiometry and precocious auditive potentials, is especially important for a positive diagnosis and etiological differentiation of vestibular syndromes.

The vestibular implant: Quo vadis?

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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.

Age-Related Change in Vestibular Ganglion Cell Populations in Individuals With Presbycusis and Normal Hearing.

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Gluth, Michael B; Nelson, Erik G

2017-04-01

We sought to establish that the decline of vestibular ganglion cell counts uniquely correlates with spiral ganglion cell counts, cochlear hair cell counts, and hearing phenotype in individuals with presbycusis. The relationship between aging in the vestibular system and aging in the cochlea is a topic of ongoing investigation. Histopathologic age-related changes the vestibular system may mirror what is seen in the cochlea, but correlations with hearing phenotype and the impact of presbycusis are not well understood. Vestibular ganglion cells, spiral ganglion cells, and cochlear hair cells were counted in specimens from individuals with presbycusis and normal hearing. These were taken from within a large collection of processed human temporal bones. Correlations between histopathology and hearing phenotype were investigated. Vestibular ganglion cell counts were positively correlated with spiral ganglion cell counts and cochlear hair cell counts and were negatively correlated with hearing phenotype. There was no statistical evidence on linear regression to suggest that the relationship between age and cell populations differed significantly according to whether presbycusis was present or not. Superior vestibular ganglion cells were more negatively correlated with age than inferior ganglion cells. No difference in vestibular ganglion cells was noted based on sex. Vestibular ganglion cell counts progressively deteriorate with age, and this loss correlates closely with changes in the cochlea, as well as hearing phenotype. However, these correlations do not appear to be unique in individuals with presbycusis as compared with those with normal hearing.

Vestibular involvement in adults with HIV/AIDS.

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Heinze, Barbara M; Vinck, Bart M; Hofmeyr, Louis M; Swanepoel, De Wet

2014-04-01

HIV/AIDS is responsible for widespread clinical manifestations involving the head, and neck. The prevalence and nature of vestibular involvement is still largely unknown. This study, aimed to describe and compare the occurrence and nature of vestibular involvement among a group of, adults infected with HIV compared to a control group. It also aimed to compare the vestibular function, of symptomatic and asymptomatic HIV positive adults who receive antiretroviral (ARV) therapies to, subjects not receiving ARV. A cross-sectional study was conducted on 53 adults (29 male, 24 female, aged 23-49 years, mean=38.5, SD=4.4) infected with HIV, compared to a control group of 38 HIV negative adults (18, male, 20 female, aged 20-49 years, mean=36.9, SD=8.2). A structured interview probed the subjective, perception of vestibular symptoms. Medical records were reviewed for CD4+ cell counts and the use of, ARV medication. An otologic assessment and a comprehensive vestibular assessment (bedside, assessments, vestibular evoked myogenic potentials, ocular motor and positional tests and bithermal, caloric irrigation) were conducted. Vestibular involvement occurred in 79.2% of subjects with HIV in all categories of disease, progression, compared to 18.4% in those without HIV. Vestibular involvement increased from 18.9% in CDC category 1 to 30.2% in category 2. Vestibular involvement was 30.1% in category 3. There were, vestibular involvement in 35.9% of symptomatic HIV positive subjects, and 41.5% in asymptomatic, HIV positive subjects. There was no significant difference in the occurrence of vestibular involvement, in subjects receiving ARV therapies compared to those not receiving ARV therapies (p=.914; chi-square, test). The odds ratio indicates that individuals with HIV have a 16.61 times higher risk of developing, vestibular involvement during their lifetime of living with the disease and that it may occur despite, being asymptomatic. Vestibular involvement was significantly more

Bioinformatic Integration of Molecular Networks and Major Pathways Involved in Mice Cochlear and Vestibular Supporting Cells.

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Requena, Teresa; Gallego-Martinez, Alvaro; Lopez-Escamez, Jose A

2018-01-01

Background : Cochlear and vestibular epithelial non-hair cells (ENHCs) are the supporting elements of the cellular architecture in the organ of Corti and the vestibular neuroepithelium in the inner ear. Intercellular and cell-extracellular matrix interactions are essential to prevent an abnormal ion redistribution leading to hearing and vestibular loss. The aim of this study is to define the main pathways and molecular networks in the mouse ENHCs. Methods : We retrieved microarray and RNA-seq datasets from mouse epithelial sensory and non-sensory cells from gEAR portal (http://umgear.org/index.html) and obtained gene expression fold-change between ENHCs and non-epithelial cells (NECs) against HCs for each gene. Differentially expressed genes (DEG) with a log2 fold change between 1 and -1 were discarded. The remaining genes were selected to search for interactions using Ingenuity Pathway Analysis and STRING platform. Specific molecular networks for ENHCs in the cochlea and the vestibular organs were generated and significant pathways were identified. Results : Between 1723 and 1559 DEG were found in the mouse cochlear and vestibular tissues, respectively. Six main pathways showed enrichment in the supporting cells in both tissues: (1) "Inhibition of Matrix Metalloproteases"; (2) "Calcium Transport I"; (3) "Calcium Signaling"; (4) "Leukocyte Extravasation Signaling"; (5) "Signaling by Rho Family GTPases"; and (6) "Axonal Guidance Si". In the mouse cochlea, ENHCs showed a significant enrichment in 18 pathways highlighting "axonal guidance signaling (AGS)" ( p = 4.37 × 10 -8 ) and "RhoGDI Signaling" ( p = 3.31 × 10 -8 ). In the vestibular dataset, there were 20 enriched pathways in ENHCs, the most significant being "Leukocyte Extravasation Signaling" ( p = 8.71 × 10 -6 ), "Signaling by Rho Family GTPases" ( p = 1.20 × 10 -5 ) and "Calcium Signaling" ( p = 1.20 × 10 -5 ). Among the top ranked networks, the most biologically significant network contained the

Influences of Vestibular System on Sympathetic Nervous System. Implications for countermeasures.

Science.gov (United States)

Denise, Pr Pierre

As gravity is a direct and permanent stress on body fluids, muscles and bones, it is not surpris-ing that weightlessness has important effects on cardiovascular and musculo-skeletal systems. However, these harmful effects do not totally result from the removal of the direct stress of gravity on these organs, but are also partially and indirectly mediated by the vestibular sys-tem. Besides its well known crucial role in spatial orientation and postural equilibrium, it is now clear that the vestibular system is also involved in the regulation of other important physi-ological systems: respiratory and cardiovascular systems, circadian regulation, food intake and even bone mineralization. The neuroanatomical substrate for these vestibular-mediated reg-ulations is still poorly defined, but there is much evidence that vestibular system has strong impacts not only on brainstem autonomic centers but on many hypothalamic nuclei as well. As autonomic nervous system controls almost all body organs, bringing into play the vestibular system by hypergravity or microgravity could virtually affects all major physiological func-tions. There is experimental evidence that weightlessness as well as vestibular lesion induce sympathetic activation thus participating in space related physiological alterations. The fact that some effects of weightlessness on biological systems are mediated by the vestibular system has an important implication for using artificial gravity as a countermeasure: artificial gravity should load not only bones and the cardiovascular system but the vestibular system as well. In short-arm centrifuges, the g load at the head level is low because the head is near the axis of rotation. If the vestibular system is involved in cardiovascular deconditioning and bone loss during weightlessness, it would be more effective to significantly stimulate it and thus it would be necessary to place the head off-axis. Moreover, as the otolithic organs are non longer stimu-lated in

Preclinical Validation of Anti-Nuclear Factor Kappa B Therapy Against Vestibular Schwannoma and Neurofibromatosis Type II

Science.gov (United States)

2016-06-01

renal failure. Pharmacologic treatment of NF2 represents a major unmet medical need. The hallmark of NF2 is bilateral vestibular schwannomas (VSs...it to test our leading hypothesis over the next year. Innovation: Our focus on NFκB as a potent pharmacologic target for NF2 is novel. Our work...diagnostic awareness among clinicians (4,5). Contrast-enhanced magnetic resonance imaging ( MRI ) of the brain is currently the gold standard for

Asymmetric vestibular stimulation reveals persistent disruption of motion perception in unilateral vestibular lesions.

Science.gov (United States)

Panichi, R; Faralli, M; Bruni, R; Kiriakarely, A; Occhigrossi, C; Ferraresi, A; Bronstein, A M; Pettorossi, V E

2017-11-01

Self-motion perception was studied in patients with unilateral vestibular lesions (UVL) due to acute vestibular neuritis at 1 wk and 4, 8, and 12 mo after the acute episode. We assessed vestibularly mediated self-motion perception by measuring the error in reproducing the position of a remembered visual target at the end of four cycles of asymmetric whole-body rotation. The oscillatory stimulus consists of a slow (0.09 Hz) and a fast (0.38 Hz) half cycle. A large error was present in UVL patients when the slow half cycle was delivered toward the lesion side, but minimal toward the healthy side. This asymmetry diminished over time, but it remained abnormally large at 12 mo. In contrast, vestibulo-ocular reflex responses showed a large direction-dependent error only initially, then they normalized. Normalization also occurred for conventional reflex vestibular measures (caloric tests, subjective visual vertical, and head shaking nystagmus) and for perceptual function during symmetric rotation. Vestibular-related handicap, measured with the Dizziness Handicap Inventory (DHI) at 12 mo correlated with self-motion perception asymmetry but not with abnormalities in vestibulo-ocular function. We conclude that 1 ) a persistent self-motion perceptual bias is revealed by asymmetric rotation in UVLs despite vestibulo-ocular function becoming symmetric over time, 2 ) this dissociation is caused by differential perceptual-reflex adaptation to high- and low-frequency rotations when these are combined as with our asymmetric stimulus, 3 ) the findings imply differential central compensation for vestibuloperceptual and vestibulo-ocular reflex functions, and 4 ) self-motion perception disruption may mediate long-term vestibular-related handicap in UVL patients. NEW & NOTEWORTHY A novel vestibular stimulus, combining asymmetric slow and fast sinusoidal half cycles, revealed persistent vestibuloperceptual dysfunction in unilateral vestibular lesion (UVL) patients. The compensation of

Profound bilateral visual loss after hysterectomy indicated for severe postpartum haemorrhage

DEFF Research Database (Denmark)

Ostri, Christoffer; Zibrandtsen, Nathalie; Larsen, Michael

2014-01-01

We present a case of a patient with bilateral posterior ischaemic optic neuropathy in the previously unreported setting of hysterectomy indicated for severe postpartum haemorrhage. The diagnosis was based on clinical and paraclinical examinations, including MRI of the head, electroretinography (ERG....... The diagnosis of perioperative posterior ischaemic optic neuropathy is mostly a clinical diagnosis. However, MRI plays a major role in excluding other causes of visual loss, and VEP, ERG and OCT are valuable supplemental diagnostic tools.......) and visual evoked potentials (VEP) testing. During 1 year of follow-up, repeated optical coherence tomography (OCT) scans demonstrated optic disc atrophy, which was interpreted as a sign of direct retrograde ganglion cell degeneration after ischaemic damage to the retrolaminar part of the optic nerves...

Aging of the Human Vestibular System

OpenAIRE

Zalewski, Christopher K.

2015-01-01

Aging affects every sensory system in the body, including the vestibular system. Although its impact is often difficult to quantify, the deleterious impact of aging on the vestibular system is serious both medically and economically. The deterioration of the vestibular sensory end organs has been known since the 1970s; however, the measurable impact from these anatomical changes remains elusive. Tests of vestibular function either fall short in their ability to quantify such anatomical deteri...

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.

Vestibular hearing and neural synchronization.

Science.gov (United States)

Emami, Seyede Faranak; Daneshi, Ahmad

2012-01-01

Objectives. Vestibular hearing as an auditory sensitivity of the saccule in the human ear is revealed by cervical vestibular evoked myogenic potentials (cVEMPs). The range of the vestibular hearing lies in the low frequency. Also, the amplitude of an auditory brainstem response component depends on the amount of synchronized neural activity, and the auditory nerve fibers' responses have the best synchronization with the low frequency. Thus, the aim of this study was to investigate correlation between vestibular hearing using cVEMPs and neural synchronization via slow wave Auditory Brainstem Responses (sABR). Study Design. This case-control survey was consisted of twenty-two dizzy patients, compared to twenty healthy controls. Methods. Intervention comprised of Pure Tone Audiometry (PTA), Impedance acoustic metry (IA), Videonystagmography (VNG), fast wave ABR (fABR), sABR, and cVEMPs. Results. The affected ears of the dizzy patients had the abnormal findings of cVEMPs (insecure vestibular hearing) and the abnormal findings of sABR (decreased neural synchronization). Comparison of the cVEMPs at affected ears versus unaffected ears and the normal persons revealed significant differences (P < 0.05). Conclusion. Safe vestibular hearing was effective in the improvement of the neural synchronization.

Vestibular disorders among adults in a tertiary hospital in Lagos, Nigeria.

Science.gov (United States)

Somefun, O A; Giwa, O S; Bamgboye, B A; Okeke-Igbokwe, I Irene; Azeez, A A Abdul

2010-10-01

Dizziness is not an uncommon complaint in the Otolaryngological clinics among other symptoms. To a large number of practitioners, the treatment of dizziness remains the same irrespective of the etiology, i.e., anti-vertiginous drugs. The objective of this study was to document the evaluation, causes and treatment of vestibular disorders among our patients. The design includes descriptive prospective study conducted in the Oto-rhino-laryngology and Orthopedic Clinics of Lagos University Teaching Hospital, Lagos and Nigerian Army Audiological Centre, 68 Nigerian Army Reference Hospital, Yaba, Lagos, Nigeria. Adult patients referred to the audiology clinic for dizziness had detailed history obtained by using structured questionnaire. General physical and neuro-otological examinations were done. Clinical diagnoses were made on standardized criteria. The patients had hearing evaluation, videonystagmography (VNG) evaluation using infrared videonystagmography system. X-ray of the cervical spine and computerized tomogram scan of internal auditory meatus and brain when indicated were done. A total of 102 patients were seen with age range between 21 and 90 years. Thirty patients (29.4%) recorded average duration of episode of vertiginous attacks in seconds, 69 (67.6%) recorded within minutes to hours and 3 (2.9%) with no definite pattern. Clinical signs on neuro-otological examination were elicited on 39 (38.2%) of the patients while on VNG the vestibular subtest mainly caloric test was abnormal unilaterally and bilaterally in 47 (46.1%) while with the oculomotor subtests, smooth pursuit tests were abnormal in 5 (6.9%), saccade tests were abnormal in 8 (7.8%) and OPK were abnormal in 9 (8.8%). Peripheral vestibular disorders are common of which benign paroxysmal positional vertigo (BPPV) was seen in 29 (28.4%), Meniere's disease in 22 (21.6%), recurrent vestibulopathy in 20 (19.6%), cervical vertigo in 18 (17.6%), psychogenic vertigo in 2 (2%), vestibular schwannoma

Extremely discrepant mutation spectrum of SLC26A4 between Chinese patients with isolated Mondini deformity and enlarged vestibular aqueduct

OpenAIRE

Huang, Shasha; Han, Dongyi; Yuan, Yongyi; Wang, Guojian; Kang, Dongyang; Zhang, Xin; Yan, Xiaofei; Meng, Xiaoxiao; Dong, Min; Dai, Pu

2011-01-01

Abstract Background Mutations in SLC26A4 cause Pendred syndrome (hearing loss with goiter) or DFNB4 (non-syndromic hearing loss with inner ear malformation, such as enlarged vestibular aqueduct or Mondini deformity). The relationship between mutations in SLC26A4 and Mondini deformity without enlarged vestibular aqueduct has not been studied in any Chinese deaf population. The purpose of this study was to assess whether mutations in the SLC26A4 gene cause Mondini deformity without an enlarged ...

Expression of vesicular glutamate transporters in peripheral vestibular structures and vestibular nuclear complex of rat.

Science.gov (United States)

Zhang, F X; Pang, Y W; Zhang, M M; Zhang, T; Dong, Y L; Lai, C H; Shum, D K Y; Chan, Y S; Li, J L; Li, Y Q

2011-01-26

Glutamate transmission from vestibular end organs to central vestibular nuclear complex (VNC) plays important role in transferring sensory information about head position and movements. Three isoforms of vesicular glutamate transporters (VGLUTs) have been considered so far the most specific markers for glutamatergic neurons/cells. In this study, VGLUT1 and VGLUT2 were immunohistochemically localized to axon terminals in VNC and somata of vestibular primary afferents in association with their central and peripheral axon endings, and VGLUT1 and VGLUT3 were co-localized to hair cells of otolith maculae and cristae ampullaris. VGLUT1 and VGLUT2 defined three subsets of Scarpa's neurons (vestibular ganglionic neurons): those co-expressing VGLUT1 and VGLUT2 or expressing only VGLUT2, and those expressing neither. In addition, many neurons located in all vestibular subnuclei were observed to contain hybridized signals for VGLUT2 mRNA and a few VNC neurons, mostly scattered in medial vestibular nucleus (MVe), displayed VGLUT1 mRNA labelling. Following unilateral ganglionectomy, asymmetries of VGLUT1-immunoreactivity (ir) and VGLUT2-ir occurred between two VNCs, indicating that the VNC terminals containing VGLUT1 and/or VGLUT2 are partly of peripheral origin. The present data indicate that the constituent cells/neurons along the vestibular pathway selectively apply VGLUT isoforms to transport glutamate into synaptic vesicles for glutamate transmission. © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Metabolic disorders of the vestibular system.

Science.gov (United States)

Rybak, L P

1995-01-01

This article reviews the impact of metabolic disorders on vestibular function. Diabetes mellitus is a disorder of glucose metabolism that can be associated with vestibular dysfunction. Vertigo can be alleviated by diet management in many cases. Elevated levels of blood lipids have been implicated in cochleovestibular disorders. Treatment with a lipid-lowering drug has resulted in improved auditory and vestibular function in a placebo-controlled trial. Hypothyroidism may affect different parts of the vestibular system depending on the severity and duration of thyroid deficiency. Severe congenital hypothyroidism can cause central vestibular disorders affecting the cerebellum, whereas mild hypothyroidism may result in peripheral vestibulopathy. Endogenous alterations in concentrations of estrogen and progesterone in the premenstrual syndrome or with the use of exogenous hormones such as oral contraceptives may trigger vertigo. Metabolic evaluations for unexplained vertigo should include a lipoprotein profile, with cholesterol and triglyceride levels, glucose tolerance test, and thyroid hormone measurements. Nutritional and drug therapy may be useful to reverse the vestibular dysfunction.

Hearing, speech, language, and vestibular disorders in the fetal alcohol syndrome: a literature review.

Science.gov (United States)

Church, M W; Kaltenbach, J A

1997-05-01

Fetal alcohol syndrome (FAS) is characterized in part by mental impairment, as well as craniofacial and ocular anomalies. These conditions are traditionally associated with childhood hearing disorders, because they all have a common embryonic origin in malformations of the first and second branchial arches, and have similar critical periods of vulnerability to toxic insult. A review of human and animal research indicates that there are four types of hearing disorders associated with FAS. These are: (1) a developmental delay in auditory maturation, (2) sensorineural hearing loss, (3) intermittent conductive hearing loss due to recurrent serous otitis media, and (4) central hearing loss. The auditory and vestibular systems share the same peripheral apparatuses (the inner ear and eighth cranial nerve) and are embryologically and structurally similar. Consequently, vestibular disorders in FAS children might be expected. The evidence for vestibular dysfunction in FAS is ambiguous, however. Like other syndromes associated with craniofacial anomalies, hearing disorders, and mental impairment, FAS is also characterized by a high prevalence of speech and language pathology. Hearing disorders are a form of sensory deprivation. If present during early childhood, they can result in permanent hearing, language, and mental impairment. Early identification and intervention to treat hearing, language, and speech disorders could therefore result in improved outcome for the FAS child. Specific recommendations are made for intervention and future research.

Auditory adaptation testing as a tool for investigating tinnitus origin: two patients with vestibular schwannoma.

Science.gov (United States)

Silverman, Carol A; Silman, Shlomo; Emmer, Michele B

2017-06-01

To enhance the understanding of tinnitus origin by disseminating two case studies of vestibular schwannoma (VS) involving behavioural auditory adaptation testing (AAT). Retrospective case study. Two adults who presented with unilateral, non-pulsatile subjective tinnitus and bilateral normal-hearing sensitivity. At the initial evaluation, the otolaryngologic and audiologic findings were unremarkable, bilaterally. Upon retest, years later, VS was identified. At retest, the tinnitus disappeared in one patient and was slightly attenuated in the other patient. In the former, the results of AAT were positive for left retrocochlear pathology; in the latter, the results were negative for the left ear although a moderate degree of auditory adaptation was present despite bilateral normal-hearing sensitivity. Imaging revealed a small VS in both patients, confirmed surgically. Behavioural AAT in patients with tinnitus furnishes a useful tool for exploring tinnitus origin. Decrease or disappearance of tinnitus in patients with auditory adaptation suggests that the tinnitus generator is the cochlea or the cochlear nerve adjacent to the cochlea. Patients with unilateral tinnitus and bilateral, symmetric, normal-hearing thresholds, absent other audiovestibular symptoms, should be routinely monitored through otolaryngologic and audiologic re-evaluations. Tinnitus decrease or disappearance may constitute a red flag for retrocochlear pathology.

Clinical and logopaedic results of simultaneous and sequential bilateral implants in children with severe and/or profound bilateral sensorineural hearing loss: A literature review.

Science.gov (United States)

López-Torrijo, Manuel; Mengual-Andrés, Santiago; Estellés-Ferrer, Remedios

2015-06-01

This article carries out a literature review of the advantages and limitations of the simultaneous bilateral cochlear implantation (SCI) compared to those of the sequential bilateral cochlear implantation (SBCI) and the unilateral cochlear implantation (UCI). The variables analysed in said comparison are: safety and surgical technique, SCI incidence, effectiveness, impact of the inter-implant interval, costs and financing, impact on brain plasticity, impact on speech and language development, main benefits, main disadvantages and concerns, and predictive factors of prognosis. Although the results are not conclusive, all variables analysed seem to point towards observable benefits of SCI in comparison with SBCI or UCI. This tendency should be studied in more depth in multicentre studies with higher methodological rigour, more comprehensive samples and periods and other determining variables (age at the time of implantation, duration and degree of the hearing loss, rehabilitation methodologies used, family involvement, etc.). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Model-based Vestibular Afferent Stimulation: Modular Workflow for Analyzing Stimulation Scenarios in Patient Specific and Statistical Vestibular Anatomy

Directory of Open Access Journals (Sweden)

Michael Handler

2017-12-01

Full Text Available Our sense of balance and spatial orientation strongly depends on the correct functionality of our vestibular system. Vestibular dysfunction can lead to blurred vision and impaired balance and spatial orientation, causing a significant decrease in quality of life. Recent studies have shown that vestibular implants offer a possible treatment for patients with vestibular dysfunction. The close proximity of the vestibular nerve bundles, the facial nerve and the cochlear nerve poses a major challenge to targeted stimulation of the vestibular system. Modeling the electrical stimulation of the vestibular system allows for an efficient analysis of stimulation scenarios previous to time and cost intensive in vivo experiments. Current models are based on animal data or CAD models of human anatomy. In this work, a (semi-automatic modular workflow is presented for the stepwise transformation of segmented vestibular anatomy data of human vestibular specimens to an electrical model and subsequently analyzed. The steps of this workflow include (i the transformation of labeled datasets to a tetrahedra mesh, (ii nerve fiber anisotropy and fiber computation as a basis for neuron models, (iii inclusion of arbitrary electrode designs, (iv simulation of quasistationary potential distributions, and (v analysis of stimulus waveforms on the stimulation outcome. Results obtained by the workflow based on human datasets and the average shape of a statistical model revealed a high qualitative agreement and a quantitatively comparable range compared to data from literature, respectively. Based on our workflow, a detailed analysis of intra- and extra-labyrinthine electrode configurations with various stimulation waveforms and electrode designs can be performed on patient specific anatomy, making this framework a valuable tool for current optimization questions concerning vestibular implants in humans.

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

Science.gov (United States)

Noohi, Fatemeh; Kinnaird, Catherine; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar; Seidler, Rachael

2014-01-01

The aim of the current study was to characterize the 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 saccular Vestibular Evoked Myogenic Potentials (VEMP) (Colebatch & Halmagyi 1992; Colebatch et al. 1994). Some researchers have reported that airconducted skull tap elicits both saccular and utricle VEMPs, while being faster and less irritating for the subjects (Curthoys et al. 2009, Wackym et al., 2012). 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 the vestibular disorders related to otolith deficits. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, pre and post central gyri, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation (Bottini et al., 1994; Dieterich et al., 2003; Emri et al., 2003; Schlindwein et al., 2008; Janzen et al., 2008). Here we hypothesized that the skull tap elicits the similar pattern of cortical activity as the auditory tone burst. Subjects put on a set of MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in supine position, with eyes closed. All subjects received both forms of the stimulation, however, the order of stimulation with auditory tone burst and air-conducted skull tap was counterbalanced across subjects. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular cortex, resulting in vestibular response (Halmagyi et al., 1995). Auditory tone bursts were also delivered for comparison. To validate

Diagnostics and therapy of vestibular schwannomas – an interdisciplinary challenge

Science.gov (United States)

Rosahl, Steffen; Bohr, Christopher; Lell, Michael; Hamm, Klaus; Iro, Heinrich

2017-01-01

the case presentations. Important criteria for decision making are size and growth rate of the tumor, hearing of the patient and the probability of total tumor resection with preservation of hearing and facial nerve function, age and comorbidity of the patient, best possible control of vertigo and tinnitus and last but not least the patient’s preference and choice. In addition to this, the experience and the results of a given center with each treatment modality will figure in the decision making process. We will discuss findings that are reported in the literature regarding facial nerve function, hearing, vertigo, tinnitus, and headache and reflect on recent studies on their influence on the patient’s quality of life. Vertigo plays an essential role in this framework since it is an independent predictor of quality of life and a patient’s dependence on social welfare. Pathognomonic bilateral vestibular schwannomas that occur in patients suffering from neurofibromatosis typ-2 (NF2) differ from spontaneous unilateral tumors in their biologic behavior. Treatment of neurofibromatosis type-2 patients requires a multidisciplinary team, especially because of the multitude of separate intracranial and spinal lesions. Off-label chemotherapy with Bevacizumab can stabilize tumor size of vestibular schwannomas and even improve hearing over longer periods of time. Hearing rehabilitation in NF2 patients can be achieved with cochlear and auditory brainstem implants. PMID:29279723

Task-dependent vestibular feedback responses in reaching.

Science.gov (United States)

Keyser, Johannes; Medendorp, W Pieter; Selen, Luc P J

2017-07-01

When reaching for an earth-fixed object during self-rotation, the motor system should appropriately integrate vestibular signals and sensory predictions to compensate for the intervening motion and its induced inertial forces. While it is well established that this integration occurs rapidly, it is unknown whether vestibular feedback is specifically processed dependent on the behavioral goal. Here, we studied whether vestibular signals evoke fixed responses with the aim to preserve the hand trajectory in space or are processed more flexibly, correcting trajectories only in task-relevant spatial dimensions. We used galvanic vestibular stimulation to perturb reaching movements toward a narrow or a wide target. Results show that the same vestibular stimulation led to smaller trajectory corrections to the wide than the narrow target. We interpret this reduced compensation as a task-dependent modulation of vestibular feedback responses, tuned to minimally intervene with the task-irrelevant dimension of the reach. These task-dependent vestibular feedback corrections are in accordance with a central prediction of optimal feedback control theory and mirror the sophistication seen in feedback responses to mechanical and visual perturbations of the upper limb. NEW & NOTEWORTHY Correcting limb movements for external perturbations is a hallmark of flexible sensorimotor behavior. While visual and mechanical perturbations are corrected in a task-dependent manner, it is unclear whether a vestibular perturbation, naturally arising when the body moves, is selectively processed in reach control. We show, using galvanic vestibular stimulation, that reach corrections to vestibular perturbations are task dependent, consistent with a prediction of optimal feedback control theory. Copyright © 2017 the American Physiological Society.

Hereditary familial vestibular degenerative diseases.

NARCIS (Netherlands)

Sun, J.; Alphen, A.M. van; Wagenaar, M.; Huygen, P.L.M.; Hoogenraad, C.C.; Hasson, T.; Koekkoek, S.K.; Bohne, B.A.; Zeeuw, C.I. de

2001-01-01

Identification of genes involved in hereditary vestibular disease is growing at a remarkable pace. Mutant mouse technology can be an important tool for understanding the biological mechanism of human vestibular diseases.

Interferência da tontura na qualidade de vida de pacientes com síndrome vestibular periférica

Directory of Open Access Journals (Sweden)

Ganança Fernando F.

2004-01-01

Full Text Available A tontura é considerada um dos sintomas mais comuns entre adultos, podendo interferir na qualidade de vida dos pacientes que apresentam este sintoma. OBJETIVOS: Descrever os resultados obtidos à aplicação do DHI brasileiro na população estudada e compará-los com a conclusão do exame vestibular dos respectivos pacientes. FORMA DE ESTUDO: Clínico randomizado. MATERIAL E MÉTODO: Vinte e cinco pacientes consecutivos que procuraram o Ambulatório da Disciplina de Otoneurologia da UNIFESP/EPM com queixa de tontura e hipótese diagnóstica de síndrome vestibular periférica submeteram-se ao questionário DHI brasileiro. Estes pacientes, adultos de ambos os sexos apresentaram idade variando entre 44 e 88 anos. Os resultados obtidos à aplicação do DHI foram comparados aos resultados do exame vestibular dos respectivos sujeitos. RESULTADOS: Os pacientes avaliados apresentaram prejuízo na qualidade de vida devido à tontura, principalmente nos aspectos funcionais avaliados pelo DHI brasileiro. Os aspectos funcionais apresentaram-se mais comprometidos nos pacientes com Síndrome Vestibular Periférica Deficitária (SVPD, independente do acometimento vestibular uni ou bilateral, e estas diferenças foram estatisticamente significantes. CONCLUSÕES: Os pacientes com tontura crônica apresentam prejuízo na qualidade de vida, em relação aos aspectos físicos, funcionais e emocionais verificados à aplicação do DHI brasileiro. Os pacientes com SVPD apresentam maior prejuízo na qualidade de vida nos aspectos funcionais à aplicação do DHI brasileiro, em relação aos pacientes com Síndrome Vestibular Periférica Irritativa.

Aging of the Human Vestibular System

Science.gov (United States)

Zalewski, Christopher K.

2015-01-01

Aging affects every sensory system in the body, including the vestibular system. Although its impact is often difficult to quantify, the deleterious impact of aging on the vestibular system is serious both medically and economically. The deterioration of the vestibular sensory end organs has been known since the 1970s; however, the measurable impact from these anatomical changes remains elusive. Tests of vestibular function either fall short in their ability to quantify such anatomical deterioration, or they are insensitive to the associated physiologic decline and/or central compensatory mechanisms that accompany the vestibular aging process. When compared with healthy younger individuals, a paucity of subtle differences in test results has been reported in the healthy older population, and those differences are often observed only in response to nontraditional and/or more robust stimuli. In addition, the reported differences are often clinically insignificant insomuch that the recorded physiologic responses from the elderly often fall within the wide normative response ranges identified for normal healthy adults. The damaging economic impact of such vestibular sensory decline manifests itself in an exponential increase in geriatric dizziness and a subsequent higher prevalence of injurious falls. An estimated $10 to $20 billion dollar annual cost has been reported to be associated with falls-related injuries and is the sixth leading cause of death in the elderly population, with a 20% mortality rate. With an estimated 115% increase in the geriatric population over 65 years of age by the year 2050, the number of balanced-disordered patients with a declining vestibular system is certain to reach near epidemic proportions. An understanding of the effects of age on the vestibular system is imperative if clinicians are to better manage elderly patients with balance disorders, dizziness, and vestibular disease. PMID:27516717

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.

Vestibular findings in fibromyalgia patients

Directory of Open Access Journals (Sweden)

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.

Vestibular Function and Activities of Daily Living

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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.

Presbyequilibrium in the oldest old, a combination of vestibular, oculomotor and postural deficits.

Science.gov (United States)

Tuunainen, Eeva; Poe, Dennis; Jäntti, Pirkko; Varpa, Kirsi; Rasku, Jyrki; Toppila, Esko; Pyykkö, Ilmari

2011-01-01

Dizziness, impaired balance and fear of falling are common complaints in the elderly. We evaluated the association of vestibular symptoms with vestibular findings in the elderly by posturography and video-oculography (VOG). We studied 38 oldest old subjects (≥ 85 yrs, mean age 89) living in a residential home. Vestibular symptoms were taken with a structured questionnaire, the Mini Mental State Examination (MMSE) was scored and any falls were recorded over a period of 12 months. Posturography was measured with a force platform and eye movements were measured by video-oculography. In the majority of the elderly, vestibular abnormalities were found, such as reduced vestibulo-ocular reflex gain 6/38, spontaneous nystagmus 5/38, gaze deviation nystagmus 5/38, head shaking nystagmus 9/38, pathologic head thrust test 10/38, and positional nystagmus 17/38. Posturography demonstrated two major findings: the body support area was limited and the use of vision for postural control was reduced. In principal component analysis of the vertigo, four major factors described elements of failure in the vestibular and other systems important to maintenance of balance: episodic vertigo, postural instability, multisystem failure (frail) and presyncopal imbalance. These four factors were associated in different degrees to vestibular abnormalities and falls. During the follow-up period, in 19 elderly (19/38), one or more falls were recorded. Progressive loss of balance in the aged, or "presbyequilibrium," is a complex and incompletely understood process involving vestibular, oculomotor, visual acuity, proprioception, motor, organ system and metabolic weaknesses and disorders. These factors provide a potential basis for streamlining diagnostic evaluations and aiding in planning for effective therapy. In oldest old, these problems are magnified, increasing the need for additional expertise in their care, which may be met by training specialized healthcare staff.

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.

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.

Auditory, Vestibular and Cognitive Effects due to Repeated Blast Exposure on the Warfighter

Science.gov (United States)

2012-10-01

rocket-propelled grenades (RPG) and from impacts to the head from accidents caused by enemy action, equipment failure, or other factors. The...Vestibular schwannoma o Sudden sensorineural hearing loss o Cerebrovascular disorders o Whiplash injury o Systemic disorders: e.g. chronic renal

Facial paralysis and vestibular syndrome in feedlot cattle in Argentina Paralisia facial e síndrome vestibular de bovinos em confinamento

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Ernesto Odriozola

2009-11-01

Full Text Available This paper reports 6 outbreaks of neurological disease associated with paralysis of the facial and vestibulocochlear nerves caused by intracranial space occupying lesions in feedlot cattle. The clinical signs observed were characterized by head tilt, uni or bilateral drooping and paralysis of the ears, eyelid ptosis, keratoconjunctivitis, and different degrees of ataxia. Morbidity and mortality rates ranged from 1.1 to 50% and 0 to 1%, respectively. Gross lesions observed included yellow, thickened leptomeninges, and marked enlargement of the roots of cranial nerves VII (facial and VIII (vestibulocochlear. Histopathologically, there was severe, chronic, granulomatous meningitis and, in one case, chronic, granulomatous neuritis of the VII and VIII cranial nerves. Attempts to identify bacterial, viral, or parasitic agents were unsuccessful. Based on the morphologic lesions, the clinical condition was diagnosed as facial paralysis and vestibular syndrome associated with space occupying lesions in the meninges and the cranial nerves VII and VIII. Feedlot is a practice of growing diffusion in our country and this is a first report of outbreaks of facial paralysis and vestibular disease associated with space occupying lesions in Argentina.Descrevem-se 6 surtos de uma doença neurológica com paralisia dos nervos facial e vestibulo-coclear causada por lesões intracraniais que ocupam espaço em bovinos em confinamento. Os sinais clínicos foram desvio da cabeça, queda e paralisia das orelhas, ptose palpebral, ceratoconjuntivite e diferentes graus de ataxia. As taxas de morbidade e mortalidade foram de 1.1%-50% e de 0-1%, respectivamente. As lesões macroscópicas incluíram engrossamento das meninges, que se apresentavam amareladas, e marcado engrossamento das raízes dos nervos cranianos VII (facial e VIII (vestíbulo-coclear. Histologicamente observaram-se meningite crônica granulomatosa e, em um caso, neurite granulomatosa crônica do VII e VIII

Left caloric vestibular stimulation as a tool to reveal implicit and explicit parameters of body representation.

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Sedda, A; Tonin, D; Salvato, G; Gandola, M; Bottini, G

2016-04-01

Homeostatic parameters, such as temperature, are related to body representation. In this study, we measured whether caloric vestibular stimulation (CVS) alters body temperature and tactile processing, and if in the direction predicted by a holistic body matrix representation. Skin temperature and tactile two-point discrimination (TPD) acuity were measured for both arms before, immediately after and with a delay from CVS. Participants were also administered a personality questionnaire and an anxiety inventory to rule out confounding factors. Two control experiments were planned to exclude casual variations. Our results show that temperature drops significantly in both arms after CVS. CVS also induces a bilateral improvement in tactile acuity (even though not immediately after but in the delayed condition). Finally, these effects are not due to learning, as demonstrated by the control experiment. In summary, our results suggest that vestibular stimulation updates body representation, supporting the evidence in favor of a body matrix. Copyright © 2016 Elsevier Inc. All rights reserved.

Hearing loss associated with enlarged vestibular aqueduct and zero or one mutant allele of SLC26A4.

Science.gov (United States)

Rose, Jane; Muskett, Julie A; King, Kelly A; Zalewski, Christopher K; Chattaraj, Parna; Butman, John A; Kenna, Margaret A; Chien, Wade W; Brewer, Carmen C; Griffith, Andrew J

2017-07-01

To characterize the severity and natural history of hearing loss, and the prevalence of having a cochlear implant in a maturing cohort of individuals with enlarged vestibular aqueduct (EVA) and zero or one mutant allele of SLC26A4. Prospective cohort study of subjects ascertained between 1998 and 2015 at the National Institutes of Health Clinical Center. Study subjects were 127 individuals (median age, 8 years; range, 0-59 years) with EVA in at least one ear. Ears with EVA and zero or one mutant allele of SLC26A4 had mean 0.5/1/2/4-kHz pure-tone averages of 62.6 and 52.9 dB HL, respectively, in contrast to EVA ears with two mutant alleles of SLC26A4 (88.1 dB HL; P zero, one, and two mutant alleles, respectively (P = .00833). This association was not independent (P = .534) but reflected underlying correlations with age at time of first audiogram (P = .003) or severity of hearing loss (P = .000). Ears with EVA and zero or one mutant allele of SLC26A4 have less severe hearing loss, no difference in prevalence of fluctuation, and a lower prevalence of cochlear implantation in comparison to ears with two mutant alleles of SLC26A4. NA Laryngoscope, 127:E238-E243, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

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....

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...

Cervical and ocular vestibular evoked potentials in Machado-Joseph disease: Functional involvement of otolith pathways.

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Ribeiro, Rodrigo Souza; Pereira, Melissa Marques; Pedroso, José Luiz; Braga-Neto, Pedro; Barsottini, Orlando Graziani Povoas; Manzano, Gilberto Mastrocola

2015-11-15

Machado-Joseph disease is defined as an autosomal dominant ataxic disorder caused by degeneration of the cerebellum and its connections and is associated with a broad range of clinical symptoms. The involvement of the vestibular system is responsible for several symptoms and signs observed in the individuals affected by the disease. We measured cervical and ocular vestibular evoked myogenic potentials in a sample of Machado-Joseph disease patients in order to assess functional pathways involved. Bilateral measures of cervical and ocular vestibular evoked myogenic potentials (cVEMP and oVEMP) were obtained from 14 symptomatic patients with genetically proven Machado-Joseph disease and compared with those from a control group of 20 healthy subjects. Thirteen (93%) patients showed at least one abnormal test result; oVEMP and cVEMP responses were absent in 17/28 (61%) and 11/28 (39%) measures, respectively; and prolonged latency of cVEMP was found in 3/28 (11%) measures. Of the 13 patients with abnormal responses, 9/13 (69%) patients showed discordant abnormal responses: four with absent oVEMP and present cVEMP, two with absent cVEMP and present oVEMP, and three showed unilateral prolonged cVEMP latencies. Both otolith-related vestibulocollic and vestibulo-ocular pathways are severely affected in Machado-Joseph disease patients evaluated by VEMPs. Copyright © 2015 Elsevier B.V. All rights reserved.

Bilateral External Auditory Exostoses Causing Conductive Hearing Loss: A Case Report and Literature Review of the Surfer's Ear.

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Barbon, Dennis A; Hegde, Rahul; Li, Shuo; Abdelbaki, Ahmed; Bajaj, Divyansh

2017-10-30

In patients with repeated exposure to cold water, such as cold water surfers and kayakers, the reactive exostoses can occur in the external auditory canal. The external auditory canal exostoses are multiple, benign bony growths. They can cause external auditory canal stenosis, leading to repeated otitis externa and potentially conductive hearing loss. It is vital to consider this entity in susceptible patients who report hearing loss, as timely intervention such as proper ear protection equipment can lower the risk of developing severe external auditory canal exostoses. We present a case of a 42-year-old male, cold water surfer with conductive hearing loss and bilateral external auditory canal (EAC) stenosis demonstrated on the computed tomography.

Combined ocular and cervical vestibular evoked myogenic potential in individuals with vestibular hyporeflexia and in patients with Ménière's disease.

Science.gov (United States)

Silva, Tatiana Rocha; de Resende, Luciana Macedo; Santos, Marco Aurélio Rocha

The vestibular evoked myogenic potential is a potential of mean latency that measures the muscle response to auditory stimulation. This potential can be generated from the contraction of the sternocleidomastoid muscle and also from the contraction of extraocular muscles in response to high-intensity sounds. This study presents a combined or simultaneous technique of cervical and ocular vestibular evoked myogenic potential in individuals with changes in the vestibular system, for use in otoneurologic diagnosis. To characterize the records and analyze the results of combined cervical and ocular VEMP in individuals with vestibular hyporeflexia and in those with Ménière's disease. The study included 120 subjects: 30 subjects with vestibular hyporeflexia, 30 with Ménière's disease, and 60 individuals with normal hearing. Data collection was performed by simultaneously recording the cervical and ocular vestibular evoked myogenic potential. There were differences between the study groups (individuals with vestibular hyporeflexia and individuals with Ménière's disease) and the control group for most of wave parameters in combined cervical and ocular vestibular evoked myogenic potential. For cervical vestibular evoked myogenic potential, it was observed that the prolongation of latency of the P13 and N23 waves was the most frequent finding in the group with vestibular hyporeflexia and in the group with Ménière's disease. For ocular vestibular evoked myogenic potential, prolonged latency of N10 and P15 waves was the most frequent finding in the study groups. Combined cervical and ocular vestibular evoked myogenic potential presented relevant results for individuals with vestibular hyporeflexia and for those with Ménière's disease. There were differences between the study groups and the control group for most of the wave parameters in combined cervical and ocular vestibular evoked myogenic potential. Copyright © 2016 Associação Brasileira de Otorrinolaringologia

[Threefold intraoperative electrophysiological monitoring of vestibular neurectomy].

Science.gov (United States)

Hausler, R; Kasper, A

1991-01-01

A threefold intraoperative monitoring of facial nerve, auditory nerve and vestibular nerve function was performed in 14 cases of retrosigmoidal neurectomy. The facial nerve was monitoring with a pressure transducer placed against the cheek (Opalarm system). The auditory nerve was monitored with acoustically (click) evoked early potentials and the vestibular nerve was monitored with electrically evoked vestibular potentials obtained by direct stimulation (biphasic current pulses of 0.75-mA p-p, 100 us, 20/s) of the exposed vestibular nerve in the cerebellopontine angle before, during and after neurectomy. A characteristic vertex negative peak having a latency of approximately 2 ms and approximately 0.5 uV amplitude was obtained between a forehead and an ipsilateral ear lobe electrode (2 x 1,000 averaged responses over 10 ms) before the neurectomy. This response disappeared after selective vestibular nerve section proximal to the stimulation site. A diminished response amplitude was measured after incomplete nerve section. Simultaneous acoustic masking had no influence on the vestibular potential. The 14 operated patients became all free of vertiginous spells and drop-attacks except one patient who developed a contralateral Menière's. Facial nerve function remained normal in all. Hearing preservation was obtained in 12 patients (86%). The threefold intraoperative monitoring has turned out to be an additional safety factor for facial and auditory nerve preservation and, thanks to the recording of vestibular potentials, it increased the efficiency of vestibular neurectomy.

Body ownership and embodiment: vestibular and multisensory mechanisms.

Science.gov (United States)

Lopez, C; Halje, P; Blanke, O

2008-06-01

Body ownership and embodiment are two fundamental mechanisms of self-consciousness. The present article reviews neurological data about paroxysmal illusions during which body ownership and embodiment are affected differentially: autoscopic phenomena (out-of-body experience, heautoscopy, autoscopic hallucination, feeling-of-a-presence) and the room tilt illusion. We suggest that autoscopic phenomena and room tilt illusion are related to different types of failures to integrate body-related information (vestibular, proprioceptive and tactile cues) in addition to a mismatch between vestibular and visual references. In these patients, altered body ownership and embodiment has been shown to occur due to pathological activity at the temporoparietal junction and other vestibular-related areas arguing for a key importance of vestibular processing. We also review the possibilities of manipulating body ownership and embodiment in healthy subjects through exposition to weightlessness as well as caloric and galvanic stimulation of the peripheral vestibular apparatus. In healthy subjects, disturbed self-processing might be related to interference of vestibular stimulation with vestibular cortex leading to disintegration of bodily information and altered body ownership and embodiment. We finally propose a differential contribution of the vestibular cortical areas to the different forms of altered body ownership and embodiment.

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.

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.

Newly Diagnosed Meniere's Disease: Clinical Course With Initiation of Noninvasive Treatment Including an Accounting of Vestibular Migraine.

Science.gov (United States)

Sbeih, Firas; Christov, Florian; Gluth, Michael B

2018-05-01

To describe the course of Meniere's disease with noninvasive treatment during the first few years after initial diagnosis. A retrospective review of consecutive patients with newly diagnosed definite Meniere's disease between 2013 and 2016 and a minimum follow-up of 1 year. Patients received a written plan for low sodium, water therapy, and treatment with a diuretic and/or betahistine. Subjects were screened and treated for vestibular migraine as needed. Vertigo control and hearing status at most recent follow-up were assessed. Forty-four subjects had an average follow up of 24.3 months. Thirty-four percent had Meniere's disease and vestibular migraine, and 84% had unilateral Meniere's disease. Seventy-five percent had vertigo well controlled at most recent follow-up, with only noninvasive treatments. Age, gender, body mass index, presence of vestibular migraine, bilateral disease, and duration of follow-up did not predict noninvasive treatment failure. Worse hearing threshold at 250 Hz and lower pure tone average (PTA) at the time of diagnosis did predict failure. Fifty-two percent of ears had improved PTA at most recent visit, 20% had no change, and 28% were worse Conclusions: Encountering excellent vertigo control and stable hearing after a new diagnosis of Meniere's disease is possible with noninvasive treatments. Worse hearing status at diagnosis predicted treatment failure.

Late radiation effects on hearing, vestibular function, and taste in brain tumor patients

International Nuclear Information System (INIS)

Johannesen, Tom B.; Rasmussen, Kjell; Winther, Finn Oe.; Halvorsen, Ulf; Lote, Knut

2002-01-01

Purpose: To investigate late radiation effects on hearing, vestibular function, and taste after conventional radiotherapy in brain tumor patients. Methods and Materials: Hearing, vestibular function, and taste were assessed in 33 brain tumor patients irradiated unilaterally to the tumor-bearing hemisphere and the temporal bone. Median observation time after completion of radiotherapy was 13 years; the fraction dose was 1.8 Gy, and mean radiation dose was 53.1 Gy. Results: Deep ulceration in the external ear canal and osteoradionecrosis on the irradiated side was seen in three patients. Reduced hearing was found for air and bone conduction of the irradiated side compared to the opposite side (0.25-2 kHz: 6.1 dB, 4 kHz: 10.3 dB, 6 kHz: 15.6 dB, and 8 kHz: 16.5 dB). For bone conduction, the corresponding figures were 0.25-2 kHz: 5.5 dB and 4 kHz: 8.2 dB. Three patients had a canal paresis of the irradiated side, and three patients had affection of the chorda tympani. Conclusion: Irradiation of the temporal bone with doses usually given in the treatment of patients with brain tumors may cause osteoradionecrosis, sensorineural hearing loss, dysfunction of the vestibular inner ear, and loss of taste. Head-and-neck examination should be included in the follow-up of long-term survivors

Galvanic vestibular stimulation may improve anterior bending posture in Parkinson's disease.

Science.gov (United States)

Okada, Yohei; Kita, Yorihiro; Nakamura, Junji; Kataoka, Hiroshi; Kiriyama, Takao; Ueno, Satoshi; Hiyamizu, Makoto; Morioka, Shu; Shomoto, Koji

2015-05-06

This study investigated the effects of binaural monopolar galvanic vestibular stimulation (GVS), which likely stimulates the bilateral vestibular system, on the anterior bending angle in patients with Parkinson's disease (PD) with anterior bending posture in a single-blind, randomized sham-controlled crossover trial. The seven PD patients completed two types of stimulation (binaural monopolar GVS and sham stimulation) applied in a random order 1 week apart. We measured each patient's anterior bending angles while he or she stood with eyes open and eyes closed before/after the stimulations. The anterior bending angles in both the eyes-open and the eyes-closed conditions were significantly reduced after the GVS. The amount of change in the eyes-closed condition post-GVS was significantly larger than that by sham stimulation. The amount of change in anterior bending angles in the GVS condition was not significantly correlated with Unified Parkinson's Disease Rating Scale motor score, disease duration, the duration of the postural deformities, and the anterior bending angles before the GVS. Binaural monopolar GVS might improve anterior bending posture in PD patients, irrespective of the duration and the severity of disease and postural deformities. Binaural monopolar GVS might be a novel treatment strategy to improve anterior bending posture in PD.

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

Adjustment of the dynamic weight distribution as a sensitive parameter for diagnosis of postural alteration in a rodent model of vestibular deficit.

Directory of Open Access Journals (Sweden)

Brahim Tighilet

Full Text Available Vestibular disorders, by inducing significant posturo-locomotor and cognitive disorders, can significantly impair the most basic tasks of everyday life. Their precise diagnosis is essential to implement appropriate therapeutic countermeasures. Monitoring their evolution is also very important to validate or, on the contrary, to adapt the undertaken therapeutic actions. To date, the diagnosis methods of posturo-locomotor impairments are restricted to examinations that most often lack sensitivity and precision. In the present work we studied the alterations of the dynamic weight distribution in a rodent model of sudden and complete unilateral vestibular loss. We used a system of force sensors connected to a data analysis system to quantify in real time and in an automated way the weight bearing of the animal on the ground. We show here that sudden, unilateral, complete and permanent loss of the vestibular inputs causes a severe alteration of the dynamic ground weight distribution of vestibulo lesioned rodents. Characteristics of alterations in the dynamic weight distribution vary over time and follow the sequence of appearance and disappearance of the various symptoms that compose the vestibular syndrome. This study reveals for the first time that dynamic weight bearing is a very sensitive parameter for evaluating posturo-locomotor function impairment. Associated with more classical vestibular examinations, this paradigm can considerably enrich the methods for assessing and monitoring vestibular disorders. Systematic application of this type of evaluation to the dizzy or unstable patient could improve the detection of vestibular deficits and allow predicting better their impact on posture and walk. Thus it could also allow a better follow-up of the therapeutic approaches for rehabilitating gait and balance.

Adjustment of the dynamic weight distribution as a sensitive parameter for diagnosis of postural alteration in a rodent model of vestibular deficit.

Science.gov (United States)

Tighilet, Brahim; Péricat, David; Frelat, Alais; Cazals, Yves; Rastoldo, Guillaume; Boyer, Florent; Dumas, Olivier; Chabbert, Christian

2017-01-01

Vestibular disorders, by inducing significant posturo-locomotor and cognitive disorders, can significantly impair the most basic tasks of everyday life. Their precise diagnosis is essential to implement appropriate therapeutic countermeasures. Monitoring their evolution is also very important to validate or, on the contrary, to adapt the undertaken therapeutic actions. To date, the diagnosis methods of posturo-locomotor impairments are restricted to examinations that most often lack sensitivity and precision. In the present work we studied the alterations of the dynamic weight distribution in a rodent model of sudden and complete unilateral vestibular loss. We used a system of force sensors connected to a data analysis system to quantify in real time and in an automated way the weight bearing of the animal on the ground. We show here that sudden, unilateral, complete and permanent loss of the vestibular inputs causes a severe alteration of the dynamic ground weight distribution of vestibulo lesioned rodents. Characteristics of alterations in the dynamic weight distribution vary over time and follow the sequence of appearance and disappearance of the various symptoms that compose the vestibular syndrome. This study reveals for the first time that dynamic weight bearing is a very sensitive parameter for evaluating posturo-locomotor function impairment. Associated with more classical vestibular examinations, this paradigm can considerably enrich the methods for assessing and monitoring vestibular disorders. Systematic application of this type of evaluation to the dizzy or unstable patient could improve the detection of vestibular deficits and allow predicting better their impact on posture and walk. Thus it could also allow a better follow-up of the therapeutic approaches for rehabilitating gait and balance.

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.

Bilateral vision loss in a captive cheetah (Acinonyx jubatus).

Science.gov (United States)

Walser-Reinhardt, Ladina; Wernick, Morena B; Hatt, Jean-Michel; Spiess, Bernhard M

2010-09-01

The following case report describes a 1-year-old female cheetah (Acinonyx jubatus) with bilateral blindness and unresponsive pupils. For comparison, a second healthy 2.5-year-old male cheetah without visual deficits was also examined. Clinical examination of both animals included biomicroscopy, indirect ophthalmoscopy, tonometry, and electroretinography. The young female cheetah showed no menace response, no direct or indirect pupillary light reflex, and no dazzle reflex in either eye. Fundus lesions, as detected by indirect ophthalmoscopy, are described for the female animal. In both eyes, the fundus color was green/turquoise/yellow with multiple hyperpigmented linear lesions in the tapetal area around the optic nerve. The optic nerve head was dark gray and about half the normal size suggesting bilateral optic nerve hypoplasia and retinal dysplasia or differentially optic nerve atrophy and chorioretinal scarring. The ERG had low amplitudes in the right eye but appeared normal in the left eye compared with the male cheetah. Blood levels did not suggest current taurine deficiency. This is addressed to some degree in the discussion. Bilateral optic nerve hypoplasia or optic nerve atrophy is a rare anomaly in cats and has not yet been described in a cheetah.

Avaliação vestibular por videonistagmografia de portadores de deficiência crônica de zinco por síndrome do intestino curto Vestibular evaluation using videonystagmography of chronic zinc deficient patients due to short bowell syndrome

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Gustavo Duarte Paiva Ferreira

2009-04-01

Full Text Available A presença do elemento químico zinco na via auditiva e a sua provável participação na gênese de alguns tipos de disacusia estão bem documentadas, porém não há estudos funcionais que mostrem os impacto da deficiência sistêmica de zinco no sistema vestibular, nem estudos anatômicos descritivos comprovando a existência do íon nas estruturas da via vestibular. OBJETIVO: Este estudo foi realizado com o objetivo de relacionar a alteração na homeostase do zinco com anormalidades do funcionamento da via vestibular. MATERIAL E MÉTODOS: Este é um estudo de casos, retrospectivo, clínico, onde nove indivíduos portadores de deficiência crônica de zinco, entre outros distúrbios nutricionais, consequentes à síndrome de má absorção, foram submetidos à avaliação vestibular. Os resultados deste grupo foram comparados com os resultados de um grupo considerado normal do ponto de vista nutricional (grupo controle. RESULTADOS: Todos os parâmetros da análise vestibular do grupo experimental mostraram-se alterados em comparação com o grupo controle. CONCLUSÃO: A comparação entre os grupos mostrou diferenças significativas em diversos parâmetros da análise vestibular e chamou a atenção para uma possível participação das alterações disabsortivas na origem das desordens vestibulares.The presence of zinc in the auditory pathways and its probable participation in tinnitus and hearing loss are known facts, although there are no clinical trials and experimental studies showing the impact of hypozincemia in the vestibular system and zinc existence in the vestibular pathway, respectively. AIM: This study is an attempt to correlate hypozincemia and abnormal vestibular function. METHODS: This is a clinical retrospective case study where nine patients suffering of chronic zinc deficiency had their serum zinc determined and were submitted to videonystagmography. Results were compared to a normal (control group. RESULTS: All

Effects of Noise on Speech Recognition and Listening Effort in Children with Normal Hearing and Children with Mild Bilateral or Unilateral Hearing Loss

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Lewis, Dawna; Schmid, Kendra; O'Leary, Samantha; Spalding, Jody; Heinrichs-Graham, Elizabeth; High, Robin

2016-01-01

Purpose: This study examined the effects of stimulus type and hearing status on speech recognition and listening effort in children with normal hearing (NH) and children with mild bilateral hearing loss (MBHL) or unilateral hearing loss (UHL). Method Children (5-12 years of age) with NH (Experiment 1) and children (8-12 years of age) with MBHL,…

Audiological and vestibular features in affected subjects with USH3: a genotype/phenotype correlation.

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Sadeghi, Mehdi; Cohn, Edward S; Kimberling, William J; Tranebjaerg, Lisbeth; Möller, Claes

2005-05-01

The aims were to compare the genotype/phenotype relationship between USH3 mutations and the consequent hearing and vestibular phenotype; and to compare hearing loss (HL) progression between Usher syndrome types IB, IIA and USH3. Genetic, audiometric and vestibular examinations were performed in 28 subjects with USH3. Five different mutations in USH3 were identified. Severe HL was present from an early age (4 to 6 years) in 35% of subjects with USH3. Progression of HL begins in the first decade, and approximately 50% of subjects with USH3 become profoundly deaf by age 40. Various vestibular abnormalities were found in about half (10/22) of the tested subjects with USH3. Depending on the severity of HL, subjects with USH3 might be misdiagnosed as either Usher type IB or IIA. The results from this study can be used as discriminatory features in differential diagnosis of this syndrome.

Interactive Healthcare Systems in the Home: Vestibular Rehabilitation

DEFF Research Database (Denmark)

Aarhus, Rikke; Grönvall, Erik; Larsen, Simon Bo

2010-01-01

Vestibular dysfunction is a balance disorder, causing dizziness that provokes discomfort and fall situations. This paper discusses early results from a project that aims to develop assistive technologies to support home-based rehabilitation for elderly affected by Vestibular dysfunction.......Vestibular dysfunction is a balance disorder, causing dizziness that provokes discomfort and fall situations. This paper discusses early results from a project that aims to develop assistive technologies to support home-based rehabilitation for elderly affected by Vestibular dysfunction....

Are stage IV vestibular schwannomas preoperatively different from other stages?

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Tringali, Stéphane; Dubreuil, Christian; Zaouche, Sandra; Ferber-Viart, Chantal

2008-01-01

The aim of this study was to focus on the clinical and paraclinical symptoms of patients suffering from Stage IV vestibular schwannomas (VSs). In this prospective study, we included 734 patients who have VS and candidates for operation. Patients were classified as having Stage I, II, III, or IV tumors according to Tos criteria as evaluated by magnetic resonance imaging. PREOPERATIVE CLINICAL EVALUATION: We recorded the occurrence of complaints (%) and duration (yr) of hearing loss, tinnitus, and balance disorder. Preoperative paraclinical evaluation included pure-tone (PTA) and speech audiometry, auditory brainstem response (ABR) patterns, and vestibular deficit at videonystamography (VNG). Continuous variables were compared between Stage IV and other stages using analysis of variance. Qualitative variables expressed as a percentage of presence were compared between Stage IV and other stages using percentage comparison. Quantitative Parameters. Patients with Stage IV VS were significantly younger as compared with patients with other stages. Stage IV hearing loss was greater compared with other stages at 250 and 500 Hz but smaller at 2,000 and 8,000 Hz. We found no difference in the loss of PTA between Stage IV and the other stages. Speech discriminancy score was smaller in Stage IV. The durations of hearing loss, tinnitus, and balance disorders were similar whatever the tumor stage. Auditory brainstem response patterns showed no difference in Wave III latency between Stage IV VS and other stages, whereas Wave V latency and V-I interval were higher in Stage IV. Both ABR threshold and VNG caloric deficit were higher in Stage IV VS compared with other stages. Qualitative Parameters. The percentage of patients with Stage IV was lower than that with Stages II and III. The percentage of men and women was similar in all stages. The occurrence of hearing loss was similar in all stages, whereas that of tinnitus was lower in Stage IV compared with Stages I and II. In

Immunohistochemical profile of cytokines and growth factors expressed in vestibular schwannoma and in normal vestibular nerve tissue.

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Taurone, Samanta; Bianchi, Enrica; Attanasio, Giuseppe; Di Gioia, Cira; Ierinó, Rocco; Carubbi, Cecilia; Galli, Daniela; Pastore, Francesco Saverio; Giangaspero, Felice; Filipo, Roberto; Zanza, Christian; Artico, Marco

2015-07-01

Vestibular schwannomas, also known as acoustic neuromas, are benign tumors, which originate from myelin-forming Schwann cells. They develop in the vestibular branch of the eighth cranial nerve in the internal auditory canal or cerebellopontine angle. The clinical progression of the condition involves slow and progressive growth, eventually resulting in brainstem compression. The objective of the present study was to investigate the expression level and the localization of the pro-inflammatory cytokines, transforming growth factor-β1 (TGF-β1) interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α), as well as the adhesion molecules, intracellular adhesion molecule-1 and vascular endothelial growth factor (VEGF), in order to determine whether these factors are involved in the transformation and development of human vestibular schwannoma. The present study investigated whether changes in inflammation are involved in tumor growth and if so, the mechanisms underlying this process. The results of the current study demonstrated that pro-inflammatory cytokines, including TGF-β1, IL-1β and IL-6 exhibited increased expression in human vestibular schwannoma tissue compared with normal vestibular nerve samples. TNF-α was weakly expressed in Schwann cells, confirming that a lower level of this cytokine is involved in the proliferation of Schwann cells. Neoplastic Schwann cells produce pro-inflammatory cytokines that may act in an autocrine manner, stimulating cellular proliferation. In addition, the increased expression of VEGF in vestibular schwannoma compared with that in normal vestibular nerve tissue, suggests that this factor may induce neoplastic growth via the promotion of angiogenesis. The present findings suggest that inflammation may promote angiogenesis and consequently contribute to tumor progression. In conclusion, the results of the present study indicated that VEGF and pro-inflammatory cytokines may be potential therapeutic targets in vestibular

Evaluation of postural control in unilateral vestibular hypofunction

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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.

Internal Models, Vestibular Cognition, and Mental Imagery: Conceptual Considerations.

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Mast, Fred W; Ellis, Andrew W

2015-01-01

Vestibular cognition has recently gained attention. Despite numerous experimental and clinical demonstrations, it is not yet clear what vestibular cognition really is. For future research in vestibular cognition, adopting a computational approach will make it easier to explore the underlying mechanisms. Indeed, most modeling approaches in vestibular science include a top-down or a priori component. We review recent Bayesian optimal observer models, and discuss in detail the conceptual value of prior assumptions, likelihood and posterior estimates for research in vestibular cognition. We then consider forward models in vestibular processing, which are required in order to distinguish between sensory input that is induced by active self-motion, and sensory input that is due to passive self-motion. We suggest that forward models are used not only in the service of estimating sensory states but they can also be drawn upon in an offline mode (e.g., spatial perspective transformations), in which interaction with sensory input is not desired. A computational approach to vestibular cognition will help to discover connections across studies, and it will provide a more coherent framework for investigating vestibular cognition.

Results of a prospective surgical audit of bilateral paediatric cochlear implantation in the UK.

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Broomfield, Stephen J; Murphy, John; Wild, Dominik C; Emmett, Stevan R; O'Donoghue, Gerard M

2014-09-01

Since being approved in 2009, bilateral simultaneous cochlear implantation (CI) has been the standard treatment for children in the UK who meet the criteria for CI. The aim was to report surgical outcomes of bilateral CI in the UK. Between January 2010 and December 2011, 14 UK CI centres collected data prospectively: demographics, aetiology, use of imaging, device type, surgery duration, use of intra-operative electrophysiology, length of stay, and post-operative complications. 1397 CI procedures in 961 CI recipients were included; 436 bilateral simultaneous, 394 bilateral sequential, and 131 unilateral. The majority (85%) were congenitally deaf. The commonest causes of acquired deafness were meningitis and cytomegalovirus infection. The median age for congenitally deaf bilateral simultaneous CI was 2.2 years, mean surgical duration 4.5 hours. 6.3% surgeries were day case procedures. Eight cases (2.0%) of planned bilateral CI had unilateral surgery. The overall major complication rate was 1.6% (0.9% excluding device failures), including explantation due to infection (0.2%), cerebrospinal fluid leak (0.2%), and meningitis (0.1%). There were no permanent facial nerve palsies and no deaths. Sixty-two (6.5%) immediate minor complications included 12 (1.3%) children with significant vestibular impairment. The complication rate was similar following bilateral CI compared to sequential and unilateral CI, and is comparable to other published series. This prospective multi-centre audit provides evidence that bilateral paediatric CI is a safe procedure in the UK, thus endorsing its role as a major therapeutic intervention in childhood deafness.

Cephalic tetanus presenting as acute vertigo with bilateral vestibulopathy.

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Kagoya, Ryoji; Iwasaki, Shinichi; Chihara, Yasuhiro; Ushio, Munetaka; Tsuji, Shoji; Murofushi, Toshihisa; Yamasoba, Tatsuya

2011-03-01

Cephalic tetanus is a rare form of tetanus, defined by paralysis of more than one cranial nerve. The seventh cranial nerve is the most frequently involved. We report a 58-year-old man with cephalic tetanus and bilateral vestibulopathy. The patient's initial symptoms were rotatory vertigo and hypertension. He then developed trismus and cranial nerve palsies of the fifth and seventh nerves. The caloric test and vestibular evoked mygenic potentials in response to air-conducted clicks revealed absent responses on both sides, although audiometry and auditory brainstem responses were normal in both ears. To the best of our knowledge, this is the first report of involvement of the eighth cranial nerve in cephalic tetanus.

Vestibular evoked myogenic potentials: an overview Potencial evocado miogênico vestibular: uma visão geral

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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.

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...

Neural correlates of hemispheric dominance and ipsilaterality within the vestibular system.

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Janzen, J; Schlindwein, P; Bense, S; Bauermann, T; Vucurevic, G; Stoeter, P; Dieterich, M

2008-10-01

Earlier functional imaging studies on the processing of vestibular information mainly focused on cortical activations due to stimulation of the horizontal semicircular canals in right-handers. Two factors were found to determine its processing in the temporo-parietal cortex: a dominance of the non-dominant hemisphere and an ipsilaterality of the neural pathways. In an investigation of the role of these factors in the vestibular otoliths, we used vestibular evoked myogenic potentials (VEMPs) in a fMRI study of monaural saccular-otolith stimulation. Our aim was to (1) analyze the hemispheric dominance for saccular-otolith information in healthy left-handers, (2) determine if there is a predominance of the ipsilateral saccular-otolith projection, and (3) evaluate the impact of both factors on the temporo-parieto-insular activation pattern. A block design with three stimulation and rest conditions was applied: (1) 102 dB-VEMP stimulation; (2) 65 dB-control-acoustic stimulation, (3) 102 dB-white-noise-control stimulation. After subtraction of acoustic side effects, bilateral activations were found in the posterior insula, the superior/middle/transverse temporal gyri, and the inferior parietal lobule. The distribution of the saccular-otolith activations was influenced by the two factors but with topographic disparity: whereas the inferior parts of the temporo-parietal cortex were mainly influenced by the ipsilaterality of the pathways, the upper parts reflected the dominance of the non-dominant hemisphere. This is in contrast to the processing of acoustic stimulation, which showed a predominance of the contralateral pathways. Our study proves the importance of the hemispheric preponderance also in left-handers, which is of relevance in the superior parts of the insula gyrus V, the inferior parietal lobule, and the superior temporal gyri.

Unilateral vestibular deafferentation-induced changes in calcium signaling-related molecules in the rat vestibular nuclear complex.

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Masumura, Chisako; Horii, Arata; Mitani, Kenji; Kitahara, Tadashi; Uno, Atsuhiko; Kubo, Takeshi

2007-03-23

Inquiries into the neurochemical mechanisms of vestibular compensation, a model of lesion-induced neuronal plasticity, reveal the involvement of both voltage-gated Ca(2+) channels (VGCC) and intracellular Ca(2+) signaling. Indeed, our previous microarray analysis showed an up-regulation of some calcium signaling-related genes such as the alpha2 subunit of L-type calcium channels, calcineurin, and plasma membrane Ca(2+) ATPase 1 (PMCA1) in the ipsilateral vestibular nuclear complex (VNC) following unilateral vestibular deafferentation (UVD). To further elucidate the role of calcium signaling-related molecules in vestibular compensation, we used a quantitative real-time polymerase chain reaction (PCR) method to confirm the microarray results and investigated changes in expression of these molecules at various stages of compensation (6 h to 2 weeks after UVD). We also investigated the changes in gene expression during Bechterew's phenomenon and the effects of a calcineurin inhibitor on vestibular compensation. Real-time PCR showed that genes for the alpha2 subunit of VGCC, PMCA2, and calcineurin were transiently up-regulated 6 h after UVD in ipsilateral VNC. A subsequent UVD, which induced Bechterew's phenomenon, reproduced a complete mirror image of the changes in gene expressions of PMCA2 and calcineurin seen in the initial UVD, while the alpha2 subunit of VGCC gene had a trend to increase in VNC ipsilateral to the second lesion. Pre-treatment by FK506, a calcineurin inhibitor, decelerated the vestibular compensation in a dose-dependent manner. Although it is still uncertain whether these changes in gene expression are causally related to the molecular mechanisms of vestibular compensation, this observation suggests that after increasing the Ca(2+) influx into the ipsilateral VNC neurons via up-regulated VGCC, calcineurin may be involved in their synaptic plasticity. Conversely, an up-regulation of PMCA2, a brain-specific Ca(2+) pump, would increase an efflux of Ca

Avaliação vestibular em mulheres com disfunção temporomandibular Vestibular evaluation in women with temporomandibular dysfunction

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Bianca Simone Zeigelboim

2007-06-01

Full Text Available OBJETIVO: avaliar o comportamento vestibular em pacientes com disfunção temporomandibular. MÉTODOS: avaliaram-se 27 pacientes do sexo feminino, na faixa etária de 30 a 53 anos, encaminhadas do Centro de Diagnóstico e Tratamento da Articulação Temporomandibular para o Laboratório de Otoneurologia da Universidade Tuiuti do Paraná. Realizaram-se os seguintes procedimentos: anamnese, inspeção otológica e avaliação vestibular por meio da vectoeletronistagmografia. RESULTADOS: as queixas mais freqüentes foram: dificuldade ou dor ao movimento do pescoço (77,7%, dor irradiada para ombro/braço (77,7%, zumbido e formigamento de extremidade superior (77,7%, tontura e dor de cabeça (66,6%, ansiedade (55,5%, sensação de cabeça oca (51,8%, agitação durante o sono (51,8% e depressão (51,8%. O exame vestibular esteve alterado em 20 pacientes (74,0% na prova calórica. Houve freqüência de alteração no sistema vestibular periférico. Houve predomínio das síndromes vestibulares periféricas deficitárias. CONCLUSÃO: ressalta-se a importância de se estudar a relação do sistema vestibular com a disfunção temporomandibular uma vez que observamos, na presente pesquisa, um número elevado de alteração no exame labiríntico.PURPOSE: to evaluate the vestibular functioning in patients with temporomandibular joint dysfunction. METHODS: 27 female patients were evaluated, with age varying from 30 to 53-year-old, referred from the Centre of Diagnosis and Treatment of Temporomandibular Joint Dysfunction to the Otoneurological Laboratory of Tuiuti University of Paraná. The following exams were carried out: anamnesis, otoscopy and vestibular evaluations through vectoelectronystagmography. RESULTS: the most frequent complaints were: difficulty or pain with movement of the neck (77.7%, pain irradiated to the shoulder/arm (77.7%, tinnitus and paresthesia of superior extremities (77.7% in each one, dizziness and headaches (66,6%, anxiety (55

Effects of deuterium oxide and galvanic vestibular stimulation on visual cortical cell function

International Nuclear Information System (INIS)

Reinis, S.; Landolt, J.P.; Weiss, D.S.; Money, K.E.

1984-01-01

The spontaneous and evoked unit activities of complex visual cortical cells were recorded from Brodmann's area 18 in immobilized, unanesthetized cats before, during, and after stimulation of the vestibular system. The vestibular system was stimulated by intravenous injection of deuterium oxide (D2O)--a noted nystagmogenic agent--or by direct galvanic stimulation of the labyrinth. Measures of the receptive-field areas, poststimulus time histograms, directional preferences, and the optimal speed of the light bar stimulating the cell were obtained before and after the application of D2O. Directional preferences were determined in a novel manner, using a method derived from a hierarchical clustering technique. Data were collected and analyzed from a) visual cortical cells in cats with intact labyrinths, b) visual cortical cells in cats following bilateral labrinthectomies, and c) nonvisual cortical cells in cats with intact labyrinths. The other cellular characteristics were also altered by the D2O. Galvanic stimulation of the labyrinth resembles, in its effects, the injection of D2O. In labyrinth-intact cats, the time course of area 18 spontaneous activity dramatically increased 30 min or more after D2O was administered. It peaked 2-3 h later and still had not returned to preinjection levels even 7 h after the D2O administration. In bilaterally labyrinthectomized cats, the spontaneous activity of the visual cells did not change following D2O administration. In nonvisual cells from labyrinth-intact cats, the spontaneous activity demonstrated a slight but significant decrease over time after D2O injection. In pilot studies, the cats were injected with D2O. Within 8-10 min afterward, signs of positional nystagmus commenced; and within 30 min, problems in maintaining balance were noted. This continued for 7-8 h before disappearing. In the labyrinthectomized animals, such effects were not observed

Effects of deuterium oxide and galvanic vestibular stimulation on visual cortical cell function

Energy Technology Data Exchange (ETDEWEB)

Reinis, S.; Landolt, J.P.; Weiss, D.S.; Money, K.E.

1984-03-01

The spontaneous and evoked unit activities of complex visual cortical cells were recorded from Brodmann's area 18 in immobilized, unanesthetized cats before, during, and after stimulation of the vestibular system. The vestibular system was stimulated by intravenous injection of deuterium oxide (D2O)--a noted nystagmogenic agent--or by direct galvanic stimulation of the labyrinth. Measures of the receptive-field areas, poststimulus time histograms, directional preferences, and the optimal speed of the light bar stimulating the cell were obtained before and after the application of D2O. Directional preferences were determined in a novel manner, using a method derived from a hierarchical clustering technique. Data were collected and analyzed from a) visual cortical cells in cats with intact labyrinths, b) visual cortical cells in cats following bilateral labrinthectomies, and c) nonvisual cortical cells in cats with intact labyrinths. The other cellular characteristics were also altered by the D2O. Galvanic stimulation of the labyrinth resembles, in its effects, the injection of D2O. In labyrinth-intact cats, the time course of area 18 spontaneous activity dramatically increased 30 min or more after D2O was administered. It peaked 2-3 h later and still had not returned to preinjection levels even 7 h after the D2O administration. In bilaterally labyrinthectomized cats, the spontaneous activity of the visual cells did not change following D2O administration. In nonvisual cells from labyrinth-intact cats, the spontaneous activity demonstrated a slight but significant decrease over time after D2O injection. In pilot studies, the cats were injected with D2O. Within 8-10 min afterward, signs of positional nystagmus commenced; and within 30 min, problems in maintaining balance were noted. This continued for 7-8 h before disappearing. In the labyrinthectomized animals, such effects were not observed.

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

[Clinical analysis of 102 patients with congenital inner ear malformation].

Science.gov (United States)

Zhu, X; Lian, N; Cai, Z

1995-01-01

Hearing loss and CT findings of 200 ears from 102 cases with congenital malformation of inner ear were included in our study. Hearing loss was typically bilateral severe, or total deafness. 75 percent of them were found deaf within one-year-old. In addition, 47 patients' (46%) mothers were noted to have caught a cold in first trimester of pregnancy. Temporal bone abnormalties were described as five types: 1. Michel malformation, 2. Mondini malformation, 3. enlargement of the vestibular aqueducts, 4. developmental deformity of cochlear aqueduct, 5. developmental deformity of internal acoustic meatus. Most cases showed malformations of vestibule or vestibular aqueducts.

Vestibular and balance issues following sport-related concussion.

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Valovich McLeod, Tamara C; Hale, Troy D

2015-01-01

To review relevant literature regarding the effect of concussion on vestibular function, impairments, assessments and management strategies. REASONING: Dizziness and balance impairments are common following sport-related concussion. Recommendations regarding the management of sport-related concussion suggest including tests of balance within the multifactorial assessment paradigm for concussive injuries. The literature was searched for guidelines and original studies related to vestibular impairments following concussion, oculomotor and balance assessments and treatment or rehabilitation of vestibular impairments. The databases searched included Medline, CINAHL, Sport Discus and the Cochrane Database of Systematic Reviews through October 2013. Dizziness following concussion occurs in ∼67-77% of cases and has been implicated as a risk factor for a prolonged recovery. Balance impairments also occur after concussion and last 3-10 days post-injury. Assessments of balance can be done using both clinical and instrumented measures with success. Vestibular rehabilitation has been shown to improve outcomes in patients with vestibular impairments, with one study demonstrating success in decreasing symptoms and increasing function following concussion. Best practices suggest that the assessment of vestibular function through cranial nerve, oculomotor and balance assessments are an important aspect of concussion management. Future studies should evaluate the effectiveness of vestibular rehabilitation for improving patient outcomes.

Common clinical features of children with enlarged vestibular aqueduct and Mondini dysplasia.

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Wu, Chen-Chi; Chen, Yuh-Shyang; Chen, Pei-Jer; Hsu, Chuan-Jen

2005-01-01

The purpose of the study was to investigate the etiological factors and the audiological data of different types of inner ear malformations, which the authors thought might be helpful in elucidating the inter-relation among malformations and shedding light on pathogenesis. Retrospective study from 1998 to 2002 at a tertiary care university hospital. One hundred sixty consecutive children with a total of 302 affected ears undergoing high-resolution computed tomography of the temporal bone for sensorineural hearing loss were enrolled. The image results were correlated with causes and origins, hearing loss patterns, hearing levels, and audiogram configurations. Inner ear malformation was present in 114 (38%) ears. The most common malformations were enlarged vestibular aqueduct, incomplete partition of cochlea (Mondini dysplasia), large vestibule, and semicircular canal dysplasia, presenting either as isolated finding or in combination. Eighty-four (74%) ears had abnormalities confined to these four malformations; only 30 (26%) ears showed other malformations. Patients with complex of enlarged vestibular aqueduct, Mondini dysplasia, large vestibule, and semicircular canal dysplasia (EMVS complex) demonstrated a significantly higher incidence of fluctuating hearing loss (93%) and a better hearing level compared with those with other malformations. Homogeneity in audiological features among these four malformations was also disclosed. The authors identified a distinct clinical entity, the EMVS complex, which is characterized by fluctuating hearing loss and a better hearing level. The authors proposed that malformations belonging to this complex result from a common pathogenetic mechanism.

Comparison of peripapillary retinal nerve fiber layer loss and visual outcome in fellow eyes following sequential bilateral non-arteritic anterior ischemic optic neuropathy.

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Dotan, Gad; Kesler, Anat; Naftaliev, Elvira; Skarf, Barry

2015-05-01

To report on the correlation of structural damage to the axons of the optic nerve and visual outcome following bilateral non-arteritic anterior ischemic optic neuropathy. A retrospective review of the medical records of 25 patients with bilateral sequential non-arteritic anterior ischemic optic neuropathy was performed. Outcome measures were peripapillary retinal nerve fiber layer thickness measured with the Stratus optical coherence tomography scanner, visual acuity and visual field loss. Median peripapillary retinal nerve fiber layer (RNFL) thickness, mean deviation (MD) of visual field, and visual acuity of initially involved NAION eyes (54.00 µm, -17.77 decibels (dB), 0.4, respectively) were comparable to the same parameters measured following development of second NAION event in the other eye (53.70 µm, p = 0.740; -16.83 dB, p = 0.692; 0.4, p = 0.942, respectively). In patients with bilateral NAION, there was a significant correlation of peripapillary RNFL thickness (r = 0.583, p = 0.002) and MD of the visual field (r = 0.457, p = 0.042) for the pairs of affected eyes, whereas a poor correlation was found in visual acuity of these eyes (r = 0.279, p = 0.176). Peripapillary RNFL thickness following NAION was positively correlated with MD of visual field (r = 0.312, p = 0.043) and negatively correlated with logMAR visual acuity (r = -0.365, p = 0.009). In patients who experience bilateral NAION, the magnitude of RNFL loss is similar in each eye. There is a greater similarity in visual field loss than in visual acuity between the two affected eyes with NAION of the same individual.

GABAergic systems in the vestibular nucleus and their contribution to vestibular compensation.

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Gliddon, Catherine M; Darlington, Cynthia L; Smith, Paul F

2005-01-01

GABA and the GABAA and GABAB receptors play a pivotal role in the coordination of the central vestibular pathways. The commissural inhibition, which exists between the two vestibular nucleus complexes (VNCs) and which is responsible for enhancing the dynamic sensitivity of VNC neurons to head acceleration, is known to be substantially mediated by GABA acting on GABAA and GABAB receptors. After unilateral vestibular deafferentation (UVD), the large asymmetry in spontaneous resting activity between the two VNCs is reinforced and exacerbated by the GABAergic interaction between the ipsilateral and contralateral sides. Although it has been suggested that reduced GABAergic inhibition of the ipsilateral VNC may be partially responsible for the recovery of resting activity that underlies vestibular compensation of the static symptoms of UVD, at present there are few data available to test this hypothesis systematically. There is some evidence that GABA concentrations change in the ipsilateral VNC during the development of compensation; however, it is unclear whether these changes relate to GABA release or to metabolic pools of GABA. Most biochemical studies of GABA receptors have been conducted at the gene expression level. Therefore, it is unclear whether changes in the receptor protein also occur, although the most recent data suggest that changes in GABAA and GABAB receptor density in the VNC are unlikely. The few radioligand binding data relate to GABAA receptors with benzodiazepine binding sites only. A decrease in the sensitivity of ipsilateral VNC neurons from compensated animals to GABA receptor agonists has been reported; however, these studies have employed brainstem slices and therefore the functional identity of the neurons involved has been unclear. Although it seems likely that some changes in central GABAergic systems accompany the recovery of resting activity in the ipsilateral VNC during the development of vestibular compensation, at the present stage

Progressive irreversible hearing loss is caused by stria vascularis degeneration in an Slc26a4-insufficient mouse model of large vestibular aqueduct syndrome.

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Ito, T; Nishio, A; Wangemann, P; Griffith, A J

2015-12-03

Hearing loss of patients with enlargement of the vestibular aqueduct (EVA) can fluctuate or progress, with overall downward progression. The most common detectable cause of EVA is mutations of SLC26A4. We previously described a transgenic Slc26a4-insufficient mouse model of EVA in which Slc26a4 expression is controlled by doxycycline administration. Mice that received doxycycline from conception until embryonic day 17.5 (DE17.5; doxycycline discontinued at embryonic day 17.5) had fluctuating hearing loss between 1 and 6 months of age with an overall downward progression after 6 months of age. In this study, we characterized the cochlear functional and structural changes underlying irreversible hearing loss in DE17.5 mice at 12 months of age. The endocochlear potential was decreased and inversely correlated with auditory brainstem response thresholds. The stria vascularis was thickened and edematous in ears with less severe hearing loss, and thinned and atrophic in ears with more severe hearing loss. There were pathologic changes in marginal cell morphology and gene expression that were not observed at 3 months. We conclude that strial dysfunction and degeneration are the primary causes of irreversible progressive hearing loss in our Slc26a4-insufficient mouse model of EVA. This model of primary strial atrophy may be used to explore the mechanisms of progressive hearing loss due to strial dysfunction. Published by Elsevier Ltd.

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.

Definition of fluctuant hearing loss.

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Shea, J J

1975-06-01

In summary, fluctuant hearing loss is defined as a disorder of the inner ear characterized by fullness, roaring tinnitus, and fluctuations in hearing. It is believed to be caused by an inadequate absorption of endolymph from the endolymphatic sac, with or without one or more metabolic disorders, that interferes with the delicate balance between the production and absorption of endolymph and thus produces cochlear hydrops. This triad of fullness, roaring tinnitus, and fluctuant hearing loss resulting from cochlear hydrops is much more common than the quadrad of true turning vertigo, fullness, roaring tinnitus, and fluctuant hearing loss due to vestibular and cochlear hydrops known as Meniere's disease. Although patients with fluctuant hearing loss only may eventually develop vertigo as the chief complaint and then be said to have Meniere's disease, it is remarkable how many patients continue to suffer mainly from cochlear symptoms at all times. It would appear, because of the greater frequency of fluctuant hearing loss than in Meniere's disease, that the cochlear labyrinth is more susceptible to hydrops than the vestibular labyrinth. For the purposes of diagnosis and treatment it is very useful to separate patients into those with fluctuant hearing loss and those with Meniere's disease.

Acute Unilateral Vestibular Failure Does Not Cause Spatial Hemineglect.

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Julian Conrad

Full Text Available Visuo-spatial neglect and vestibular disorders have common clinical findings and involve the same cortical areas. We questioned (1 whether visuo-spatial hemineglect is not only a disorder of spatial attention but may also reflect a disorder of higher cortical vestibular function and (2 whether a vestibular tone imbalance due to an acute peripheral dysfunction can also cause symptoms of neglect or extinction. Therefore, patients with an acute unilateral peripheral vestibular failure (VF were tested for symptoms of hemineglect.Twenty-eight patients with acute VF were assessed for signs of vestibular deficits and spatial neglect using clinical measures and various common standardized paper-pencil tests. Neglect severity was evaluated further with the Center of Cancellation method. Pathological neglect test scores were correlated with the degree of vestibular dysfunction determined by the subjective visual vertical and caloric testing.Three patients showed isolated pathological scores in one or the other neglect test, either ipsilesionally or contralesionally to the VF. None of the patients fulfilled the diagnostic criteria of spatial hemineglect or extinction.A vestibular tone imbalance due to unilateral failure of the vestibular endorgan does not cause spatial hemineglect, but evidence indicates it causes mild attentional deficits in both visual hemifields.

Bilateral occipital lobe infarction with altitudinal field loss following radiofrequency cardiac catheter ablation

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Chen Celia S

2010-03-01

Full Text Available Abstract Background Bilateral stroke following radiofrequency catheter ablation is an unusual complication and may result in bilateral altitudinal visual field defects. Bilateral altitudinal visual field defects usually result from prechiasmal pathology causing damage to both retinas or optic nerves and rarely from bilateral symmetric damage to the post chiasmal visual pathways. Case presentation A 48-year-old man complained of visual disturbance on wakening following radiofrequency catheter ablation. The patient had a CHADS score of 1 pre-operatively and no complications were noted intra-operatively. Examination revealed a bilateral superior altitudinal defect and MRI of the brain showed multifocal areas of infarction predominantly involving the occipital lobes which correlated to with the visual deficits. Conclusion While the risk of thromboembolism and perioperative stroke during radiofrequency catheter ablation is small, it is not insignificant.

Association between vestibular function and motor performance in hearing-impaired children.

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Maes, Leen; De Kegel, Alexandra; Van Waelvelde, Hilde; Dhooge, Ingeborg

2014-12-01

The clinical balance performance of normal-hearing (NH) children was compared with the balance performance of hearing-impaired (HI) children with and without vestibular dysfunction to identify an association between vestibular function and motor performance. Prospective study. Tertiary referral center. Thirty-six children (mean age, 7 yr 5 mo; range, 3 yr 8 mo-12 yr 11 mo) divided into three groups: NH children with normal vestibular responses, HI children with normal vestibular responses, and HI children with abnormal vestibular function. A vestibular test protocol (rotatory and collic vestibular evoked myogenic potential testing) in combination with three clinical balance tests (balance beam walking, one-leg hopping, one-leg stance). Clinical balance performance. HI children with abnormal vestibular test results obtained the lowest quotients of motor performance, which were significantly lower compared with the NH group (p beam walking and one-leg stance; p = 0.003 for one-leg hopping). The balance performance of the HI group with normal vestibular responses was better in comparison with the vestibular impaired group but still significantly lower compared with the NH group (p = 0.020 for balance beam walking; p = 0.001 for one-leg stance; not significant for one-leg hopping). These results indicate an association between vestibular function and motor performance in HI children, with a more distinct motor deterioration if a vestibular impairment is superimposed to the auditory dysfunction.

[Vestibular testing abnormalities in individuals with motion sickness].

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Ma, Yan; Ou, Yongkang; Chen, Ling; Zheng, Yiqing

2009-08-01

To evaluate the vestibular function of motion sickness. VNG, which tests the vestibular function of horizontal semicircular canal, and CPT, which tests vestibulospinal reflex and judge proprioceptive, visual and vestibular status, were performed in 30 motion sickness patients and 20 healthy volunteers (control group). Graybiel score was recorded at the same time. Two groups' Graybiel score (12.67 +/- 11.78 vs 2.10 +/- 6.23; rank test P<0.05), caloric test labyrinth value [(19.02 +/- 8.59) degrees/s vs (13.58 +/- 5.25) degrees/s; t test P<0.05], caloric test labyrinth value of three patients in motion sickness group exceeded 75 degrees/s. In computerized posturography testing (CPT), motion sickness patients were central type (66.7%) and disperse type (23.3%); all of control group were central type. There was statistical significance in two groups' CTP area, and motion sickness group was obviously higher than control group. While stimulating vestibulum in CPT, there was abnormality (35%-50%) in motion sickness group and none in control group. Generally evaluating CPT, there was only 2 proprioceptive hypofunction, 3 visual hypofunction, and no vestibular hypofunction, but none hypofunction in control group. Motion sickness patients have high vestibular susceptible, some with vestibular hyperfunction. In posturography, a large number of motion sickness patients are central type but no vestibular hypofunction, but it is hard to keep balance when stimulating vestibulum.

[Infrared videonystagmography in vestibular diagnosis].

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Frisina, A; Piazza, F; Quaranta, N

2000-01-01

Vestibular examination relied upon electronystagmography (ENG) for more than 50 years. This method is based on recording of nystagmus (Ny) without any possibility to see the ocular movements directly. More recently, infrared videonystagmography (VNG) entered the diagnostic protocol of vestibular disorders. VNG permits to record and visualize Ny, both in the darkness and with open eyes. Aim of the present study was to verify the possible advantages of VNG versus ENG for functional evaluation of the vestibular system in patients suffering from otoneurological disorders. To that purpose, VNG and ENG tracings were recorded in 12 patients. The preliminary results show that there are not significant differences in quantitative evaluation of Ny between the two methods. Anyhow, VNG has some technical and clinical advantages that make it the method of choice.

Optimal duration of therapy in the recovery period of vestibular diseases

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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

Vestibular feedback maintains reaching accuracy during body movement

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Reynolds, Raymond F.

2016-01-01

Key points Reaching movements can be perturbed by vestibular input, but the function of this response is unclear.Here, we applied galvanic vestibular stimulation concurrently with real body movement while subjects maintained arm position either fixed in space or fixed with respect to their body.During the fixed‐in‐space conditions, galvanic vestibular stimulation caused large changes in arm trajectory consistent with a compensatory response to maintain upper‐limb accuracy in the face of body movement.Galvanic vestibular stimulation responses were absent during the body‐fixed task, demonstrating task dependency in vestibular control of the upper limb.The results suggest that the function of vestibular‐evoked arm movements is to maintain the accuracy of the upper limb during unpredictable body movement, but only when reaching in an earth‐fixed reference frame. Abstract When using our arms to interact with the world, unintended body motion can introduce movement error. A mechanism that could detect and compensate for such motion would be beneficial. Observations of arm movements evoked by vestibular stimulation provide some support for this mechanism. However, the physiological function underlying these artificially evoked movements is unclear from previous research. For such a mechanism to be functional, it should operate only when the arm is being controlled in an earth‐fixed rather than a body‐fixed reference frame. In the latter case, compensation would be unnecessary and even deleterious. To test this hypothesis, subjects were gently rotated in a chair while being asked to maintain their outstretched arm pointing towards either earth‐fixed or body‐fixed memorized targets. Galvanic vestibular stimulation was applied concurrently during rotation to isolate the influence of vestibular input, uncontaminated by inertial factors. During the earth‐fixed task, galvanic vestibular stimulation produced large polarity‐dependent corrections in arm

Vestibular Schwannoma or acoustic neuroma

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Hekmatara M

1997-04-01

Full Text Available Vestibular schwannoma is the most common tumor of the posterior fossa of the skull. Patients referred with the primary otologic symptoms such as hearing loss, tinnitus, vertigo, imbalance, and the cranial nerve palsy. Thirty-three patients were operated and treated by a team of otolaryngologist and neurosurgeon, anudiometrist, and internist. Patients'chiefcomplaint was due to 94% hearing loss and 27% tinnitus. They scarcely complain of vertigo. If a patient refers with the palsy or paralysis of facial nerve preoperation, we must think of the facial nerve schwannoma or hemangioma or congential cholestoma or malignant metastases rather than acoustic neuroma. The best way for preoperative diagnosis is audiometry, ABR (Auditory Brain Response, and SDS (speech discrimination score with 90% success, but computer Tomography (CT scan and MRI (Magnetic Resonance Image are the valuable anatomic diagnostic radiographic devices. The best method of operation is translabirynthine approach (TLA, since it has the advantages such as an easy access to nerve paths and being the nearest path to CPA (Cerebellopontine Angle. Physicians ought to talk to patients about the importance of the microscopic surgery, surgical methods, and their probable diverse effects such as hearing loss, facial nerve palsy, and intracranial problems.

Vestibular schwannoma with contralateral facial pain – case report

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Ghodsi Mohammad

2003-03-01

Full Text Available Abstract Background Vestibular schwannoma (acoustic neuroma most commonly presents with ipsilateral disturbances of acoustic, vestibular, trigeminal and facial nerves. Presentation of vestibular schwannoma with contralateral facial pain is quite uncommon. Case presentation Among 156 cases of operated vestibular schwannoma, we found one case with unusual presentation of contralateral hemifacial pain. Conclusion The presentation of contralateral facial pain in the vestibular schwannoma is rare. It seems that displacement and distortion of the brainstem and compression of the contralateral trigeminal nerve in Meckel's cave by the large mass lesion may lead to this atypical presentation. The best practice in these patients is removal of the tumour, although persistent contralateral pain after operation has been reported.

A vestibular sensation: probabilistic approaches to spatial perception.

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Angelaki, Dora E; Klier, Eliana M; Snyder, Lawrence H

2009-11-25

The vestibular system helps maintain equilibrium and clear vision through reflexes, but it also contributes to spatial perception. In recent years, research in the vestibular field has expanded to higher-level processing involving the cortex. Vestibular contributions to spatial cognition have been difficult to study because the circuits involved are inherently multisensory. Computational methods and the application of Bayes theorem are used to form hypotheses about how information from different sensory modalities is combined together with expectations based on past experience in order to obtain optimal estimates of cognitive variables like current spatial orientation. To test these hypotheses, neuronal populations are being recorded during active tasks in which subjects make decisions based on vestibular and visual or somatosensory information. This review highlights what is currently known about the role of vestibular information in these processes, the computations necessary to obtain the appropriate signals, and the benefits that have emerged thus far.

Vestibular Function Impairment in Alzheimer's Disease.

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Nakamagoe, Kiyotaka; Fujimiya, Suguru; Koganezawa, Tadachika; Kadono, Kotarou; Shimizu, Kotone; Fujizuka, Natsu; Takiguchi, Shino; Ueno, Tomoyuki; Monzen, Tatsuya; Tamaoka, Akira

2015-01-01

Falls and fractures due to impaired balance in patients with Alzheimer's disease (AD) have an adverse effect on the clinical course of the disease. To evaluate balance impairment in AD from the viewpoint of vestibular functional impairment. The subjects were 12 patients with AD, 12 dementia-free elderly adults, and 12 younger adults. Vestibular function was assessed using a stepping test, caloric nystagmus, and a visual suppression (VS) test. The stepping test was abnormal in 9 of the 12 patients in the AD group. An abnormal stepping test was not associated with self-reported dizziness or tendency to fall. Significant VS abnormalities were present in the AD group. The suppression rate of VS was lower in AD patients with either a tendency to fall or constructional apraxia than in AD patients without either. The velocity of the rapid phase of caloric nystagmus before the VS test was similar in the AD group and the elderly control group. Significant abnormalities of both caloric nystagmus and VS were not present in either the elderly or the younger control groups. AD could involve impairments in the vestibular control of balance. The VS test is useful for assessing the tendency to fall in AD. Impairment of VS in AD might arise from cerebral vestibular cortex impairment rather than comorbid peripheral vestibular disorders.

ALDH1A3 loss of function causes bilateral anophthalmia/microphthalmia and hypoplasia of the optic nerve and optic chiasm.

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Yahyavi, Mani; Abouzeid, Hana; Gawdat, Ghada; de Preux, Anne-Sophie; Xiao, Tong; Bardakjian, Tanya; Schneider, Adele; Choi, Alex; Jorgenson, Eric; Baier, Herwig; El Sada, Mohamad; Schorderet, Daniel F; Slavotinek, Anne M

2013-08-15

The major active retinoid, all-trans retinoic acid, has long been recognized as critical for the development of several organs, including the eye. Mutations in STRA6, the gene encoding the cellular receptor for vitamin A, in patients with Matthew-Wood syndrome and anophthalmia/microphthalmia (A/M), have previously demonstrated the importance of retinol metabolism in human eye disease. We used homozygosity mapping combined with next-generation sequencing to interrogate patients with anophthalmia and microphthalmia for new causative genes. We used whole-exome and whole-genome sequencing to study a family with two affected brothers with bilateral A/M and a simplex case with bilateral anophthalmia and hypoplasia of the optic nerve and optic chiasm. Analysis of novel sequence variants revealed homozygosity for two nonsense mutations in ALDH1A3, c.568A>G, predicting p.Lys190*, in the familial cases, and c.1165A>T, predicting p.Lys389*, in the simplex case. Both mutations predict nonsense-mediated decay and complete loss of function. We performed antisense morpholino (MO) studies in Danio rerio to characterize the developmental effects of loss of Aldh1a3 function. MO-injected larvae showed a significant reduction in eye size, and aberrant axonal projections to the tectum were noted. We conclude that ALDH1A3 loss of function causes anophthalmia and aberrant eye development in humans and in animal model systems.

HASHIMOTO THYROIDITIS AND VESTIBULAR DYSFUNCTION.

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Chiarella, Giuseppe; Russo, Diego; Monzani, Fabio; Petrolo, Claudio; Fattori, Bruno; Pasqualetti, Giuseppe; Cassandro, Ettore; Costante, Giuseppe

2017-07-01

The aim of this review was to analyze the existing literature concerning the relationship between Hashimoto thyroiditis (HT) and vestibular dysfunction. We used electronic databases (PubMed, EMBASE, Cochrane Library) to search and collect all published articles about the association between HT and vestibular disorders. Several observational and retrospective studies have postulated a relationship between thyroid autoimmunity and vestibular disorders. In most cases, an appropriate control group was lacking, and the impact of thyroid functional status could not precisely be established. In recent years, two well-designed prospective studies have provided convincing evidence that the association is not random. One article reported that patients with Ménière disease (MD) had a significantly higher prevalence of positive anti-thyroid autoantibody as compared to healthy controls. Moreover, more than half of MD patients had either positive anti-thyroid or non-organ-specific autoantibody titers, compared to less than 30% of both patients with unilateral vestibular paresis without cochlear involvement and healthy controls. Another study found that patients with benign paroxysmal positional vertigo (BPPV) had significantly higher serum thyroid-stimulating hormone and antithyroid autoantibody levels than healthy controls. Additionally, almost one-fifth of euthyroid patients with HT had signs of BPPV. The published results indicate that patients with MD or BPPV are potential candidates to also develop HT. Thus, in HT patients, the presence of even slight symptoms or signs potentially related to vestibular lesions should be carefully investigated. AITD = autoimmune thyroid disease; BPPV = benign paroxysmal positional vertigo; EH = endolymphatic hydrops; HT = Hashimoto thyroiditis; L-T 4 = L-thyroxine; MD = Ménière disease; PS = Pendred syndrome; Tg = thyroglobulin; TPO = thyroid peroxidase; TSH = thyroid-stimulating hormone.

Ceratite bilateral por Acanthamoeba: relato de caso Bilateral Acanthamoeba keratitis: case report

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Wilson Nahmatallah Obeid

2003-12-01

Full Text Available A ceratite por Acanthamoeba é uma infecção ocular grave que, apesar dos recentes progressos no diagnóstico e tratamento, ainda provoca prolongada morbidade e perda da acuidade visual. Relatamos um caso de ceratite bilateral por Acanthamoeba em usuário de lentes de contato, que é o primeiro caso descrito na literatura brasileira.Acanthamoeba keratitis is a severe ocular infection which even with recent progress in diagnosis and treatment still causes long morbidity and loss of visual acuity. We describe a case of bilateral Acanthamoeba keratitis in a user of contact lenses, which is the first case discussed in Brazilian literature.

Hoxb1 controls anteroposterior identity of vestibular projection neurons.

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Chen, Yiju; Takano-Maruyama, Masumi; Fritzsch, Bernd; Gaufo, Gary O

2012-01-01

The vestibular nuclear complex (VNC) consists of a collection of sensory relay nuclei that integrates and relays information essential for coordination of eye movements, balance, and posture. Spanning the majority of the hindbrain alar plate, the rhombomere (r) origin and projection pattern of the VNC have been characterized in descriptive works using neuroanatomical tracing. However, neither the molecular identity nor developmental regulation of individual nucleus of the VNC has been determined. To begin to address this issue, we found that Hoxb1 is required for the anterior-posterior (AP) identity of precursors that contribute to the lateral vestibular nucleus (LVN). Using a gene-targeted Hoxb1-GFP reporter in the mouse, we show that the LVN precursors originate exclusively from r4 and project to the spinal cord in the stereotypic pattern of the lateral vestibulospinal tract that provides input into spinal motoneurons driving extensor muscles of the limb. The r4-derived LVN precursors express the transcription factors Phox2a and Lbx1, and the glutamatergic marker Vglut2, which together defines them as dB2 neurons. Loss of Hoxb1 function does not alter the glutamatergic phenotype of dB2 neurons, but alters their stereotyped spinal cord projection. Moreover, at the expense of Phox2a, the glutamatergic determinants Lmx1b and Tlx3 were ectopically expressed by dB2 neurons. Our study suggests that the Hox genes determine the AP identity and diversity of vestibular precursors, including their output target, by coordinating the expression of neurotransmitter determinant and target selection properties along the AP axis.

Prophylactic treatment of vestibular migraine

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Márcio Cavalcante Salmito

Full Text Available 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 treatment scarce. Objective: To evaluate the efficacy of prophylactic treatment used in patients from a VM outpatient clinic. Methods: Review of medical records from patients with VM according to the criteria of the Bárány Society/International Headache Society of 2012 criteria. The drugs used in the treatment and treatment response obtained through the visual analog scale (VAS for dizziness and headache were assessed. The pre and post-treatment VAS scores were compared (the improvement was evaluated together and individually, per drug used. Associations with clinical subgroups of patients were also assessed. Results: Of the 88 assessed records, 47 were eligible. We included patients that met the diagnostic criteria for VM and excluded those whose medical records were illegible and those of patients with other disorders causing dizziness and/or headache that did not meet the 2012 criteria for VM. 80.9% of the patients showed improvement with prophylaxis (p < 0.001. Amitriptyline, Flunarizine, Propranolol and Topiramate improved vestibular symptoms (p < 0.001 and headache (p < 0.015. The four drugs were effective in a statistically significant manner. There was a positive statistical association between the time of vestibular symptoms and clinical improvement. There was no additional benefit in hypertensive patients who used antihypertensive drugs as prophylaxis or depressed patients who used antidepressants in relation to other prophylactic drugs. Drug

Long-term hearing preservation in vestibular schwannoma

DEFF Research Database (Denmark)

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

2010-01-01

The aim of the present study was to evaluate the long-term hearing during "wait and scan" management of vestibular schwannomas.......The aim of the present study was to evaluate the long-term hearing during "wait and scan" management of vestibular schwannomas....

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.

Balancing awareness: Vestibular signals modulate visual consciousness in the absence of awareness.

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Salomon, Roy; Kaliuzhna, Mariia; Herbelin, Bruno; Blanke, Olaf

2015-11-01

The processing of visual and vestibular information is crucial for perceiving self-motion. Visual cues, such as optic flow, have been shown to induce and alter vestibular percepts, yet the role of vestibular information in shaping visual awareness remains unclear. Here we investigated if vestibular signals influence the access to awareness of invisible visual signals. Using natural vestibular stimulation (passive yaw rotations) on a vestibular self-motion platform, and optic flow masked through continuous flash suppression (CFS) we tested if congruent visual-vestibular information would break interocular suppression more rapidly than incongruent information. We found that when the unseen optic flow was congruent with the vestibular signals perceptual suppression as quantified with the CFS paradigm was broken more rapidly than when it was incongruent. We argue that vestibular signals impact the formation of visual awareness through enhanced access to awareness for congruent multisensory stimulation. Copyright © 2015 Elsevier Inc. All rights reserved.

Progression of changes in the sensorial elements of the cochlear and peripheral vestibular systems: The otitis media continuum.

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Monsanto, Rafael da Costa; Schachern, Patricia; Paparella, Michael M; Cureoglu, Sebahattin; Penido, Norma de Oliveira

2017-08-01

Our study aimed to evaluate pathologic changes in the cochlear (inner and outer hair cells and stria vascularis) and vestibular (vestibular hair cells, dark, and transitional cells) sensorial elements in temporal bones from donors who had otitis media. We studied 40 temporal bones from such donors, which were categorized in serous otitis media (SOM), serous-purulent otitis media (SPOM), mucoid/mucoid-purulent otitis media (MOM/MPOM), and chronic otitis media (COM); control group comprised 10 nondiseased temporal bones. We found significant loss of inner and outer cochlear hair cells in the basal turn of the SPOM, MOM/MPOM and COM groups; significant loss of vestibular hair cells was observed in the MOM/MPOM and COM groups. All otitis media groups had smaller mean area of the stria vascularis in the basal turn of the cochlea when compared to controls. In conclusion, our study demonstrated more severe pathologic changes in the later stages of the continuum of otitis media (MOM/MPOM and COM). Those changes seem to progress from the basal turn of the cochlea (stria vascularis, then inner and outer hair cells) to the middle turn of the cochlea and to the saccule and utricle in the MOM/MPOM and COM stages. Copyright © 2017 Elsevier B.V. All rights reserved.

Three-dimensional head-mounted gaming task procedure maximizes effects of vestibular rehabilitation in unilateral vestibular hypofunction: a randomized controlled pilot trial.

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Micarelli, Alessandro; Viziano, Andrea; Augimeri, Ivan; Micarelli, Domenico; Alessandrini, Marco

2017-12-01

Considering the emerging advantages related to virtual reality implementation in clinical rehabilitation, the aim of the present study was to discover possible (i) improvements achievable in unilateral vestibular hypofunction patients using a self-assessed head-mounted device (HMD)-based gaming procedure when combined with a classical vestibular rehabilitation protocol (HMD group) as compared with a group undergoing only vestibular rehabilitation and (ii) HMD procedure-related side effects. Therefore, 24 vestibular rehabilitation and 23-matched HMD unilateral vestibular hypofunction individuals simultaneously underwent a 4-week rehabilitation protocol. Both otoneurological measures (vestibulo-ocular reflex gain and postural arrangement by studying both posturography parameters and spectral values of body oscillation) and performance and self-report measures (Italian Dizziness Handicap Inventory; Activities-specific Balance Confidence scale; Zung Instrument for Anxiety Disorders, Dynamic Gait Index; and Simulator Sickness Questionnaire) were analyzed by means of a between-group/within-subject analysis of variance model. A significant post-treatment between-effect was found, and the HMD group demonstrated an overall improvement in vestibulo-ocular reflex gain on the lesional side, in posturography parameters, in low-frequency spectral domain, as well as in Italian Dizziness Handicap Inventory and Activities-specific Balance Confidence scale scores. Meanwhile, Simulator Sickness Questionnaire scores demonstrated a significant reduction in symptoms related to experimental home-based gaming tasks during the HMD procedure. Our findings revealed the possible advantages of HMD implementation in vestibular rehabilitation, suggesting it as an innovative, self-assessed, low-cost, and compliant tool useful in maximizing vestibular rehabilitation outcomes.

Towards a neuromorphic vestibular system.

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Corradi, Federico; Zambrano, Davide; Raglianti, Marco; Passetti, Giovanni; Laschi, Cecilia; Indiveri, Giacomo

2014-10-01

The vestibular system plays a crucial role in the sense of balance and spatial orientation in mammals. It is a sensory system that detects both rotational and translational motion of the head, via its semicircular canals and otoliths respectively. In this work, we propose a real-time hardware model of an artificial vestibular system, implemented using a custom neuromorphic Very Large Scale Integration (VLSI) multi-neuron chip interfaced to a commercial Inertial Measurement Unit (IMU). The artificial vestibular system is realized with spiking neurons that reproduce the responses of biological hair cells present in the real semicircular canals and otholitic organs. We demonstrate the real-time performance of the hybrid analog-digital system and characterize its response properties, presenting measurements of a successful encoding of angular velocities as well as linear accelerations. As an application, we realized a novel implementation of a recurrent integrator network capable of keeping track of the current angular position. The experimental results provided validate the hardware implementation via comparisons with a detailed computational neuroscience model. In addition to being an ideal tool for developing bio-inspired robotic technologies, this work provides a basis for developing a complete low-power neuromorphic vestibular system which integrates the hardware model of the neural signal processing pathway described with custom bio-mimetic gyroscopic sensors, exploiting neuromorphic principles in both mechanical and electronic aspects.

Avaliação do efeito da cafeína no teste vestibular Evaluation of the caffeine effect in the vestibular test

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Lilian Felipe

2005-12-01

Full Text Available Há controvérsias sobre a interferência da cafeína no teste vestibular. O café é a fonte mais rica em cafeína. Enquanto em alguns serviços os pacientes são orientados a suspender a ingestão de café 24 a 48 horas antes da realização do teste, outros não consideram necessária a suspensão da ingestão dessa bebida. OBJETIVO: Avaliar o efeito da cafeína no resultado do teste vestibular. FORMA DE ESTUDO: clínico com coorte transversal. MATERIAL E MÉTODO: Estudo comparativo, transversal, pareado. O teste vestibular foi realizado em duplicidade, com intervalo máximo de cinco dias entre um e outro exame. No primeiro teste, os pacientes foram orientados a não ingerir café 24 horas antes do exame; no segundo teste, os pacientes foram orientados a beber café como de costume. Todos os participantes tinham indicação clínica de se submeter ao teste vestibular e tinham o hábito de tomar café. RESULTADOS: Participaram do estudo 19 mulheres com idade média de 49,5 anos. O consumo médio de café foi de três xícaras por dia. As queixas de ansiedade e cefaléia foram associadas ao teste realizado com suspensão do café. Não houve diferença estatisticamente significante nos resultados dos exames realizados com e sem ingestão de café. CONCLUSÃO: A ingestão moderada de café não interferiu no resultado do teste vestibular. Considerando ser recomendável que o paciente esteja tranqüilo ao se submeter ao teste vestibular e que a meia-vida da cafeína é de apenas seis horas, sugerimos que a orientação para a suspensão súbita e completa da ingestão moderada de café antes do teste vestibular para os indivíduos habituados à ingestão diária seja reavaliada.Exist controversy about the interference of the caffeine in the vestibular test. Coffee is the richest source of caffeine. While in some services, the patients were orient to suspend the ingestion of caffeine 24 to 48 hours before the vestibular test, other not consider

Development and regeneration of vestibular hair cells in mammals.

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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.

Immunocytochemical and stereological analysis of GABA(B) receptor subunit expression in the rat vestibular nucleus following unilateral vestibular deafferentation.

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Zhang, Rong; Ashton, John; Horii, Arata; Darlington, Cynthia L; Smith, Paul F

2005-03-10

The process of behavioral recovery that occurs following damage to one vestibular labyrinth, vestibular compensation, has been attributed in part to a down-regulation of GABA(B) receptors in the vestibular nucleus complex (VNC) ipsilateral to the lesion, which could potentially reduce commissural inhibition from the contralateral VNC. In this study, we tested the possibility that this occurs through a decrease in the expression of either the GABA(B1) or GABA(B2) subunits of the GABA(B) receptor. We used Western blotting to quantify the expression of these subunits in the VNC at 10 h and 50 h following unilateral vestibular deafferentation (UVD) or sham surgery in rats. We then used immunocytochemistry and stereological counting methods to estimate the number of neurons expressing these subunits in the MVN at 10 h and 2 weeks following UVD or sham surgery. Compared to sham controls, we found no significant changes in either the expression of the two GABA(B) receptor subunits in the VNC or in the number of MVN neurons expressing these GABA(B) receptor subunits post-UVD. These results suggest that GABA(B) receptor expression does not change substantially in the VNC during the process of vestibular compensation.

Influence of spontaneous nystagmus with eyes closed on computerized vestibular exam of patients with chronic peripheral

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Shin, Elizabeth

2010-06-01

Full Text Available Introduction: The spontaneous nystagmus with eyes closed (NEOF can modify the results obtained during some evidence of vestibular, leading to erroneous conclusions. Objective: To characterize the patients and the type of influence on the evidence of NEOF vectonystagmography digital. Method: Retrospective study based on survey charts of patients with the presence of NEOF vectonystagmography digital, in the Outpatient Equilibriometria UNIFESP-EPM, in the years 2000 to 2007. Comparisons were made between genders, ages, direction, angular velocity of NEOF, completion of entrance examination and its influence on the results of caloric testing. Results: We found 73.7% of the population was female, mean age of 55.08 years; NEOF prevalence of horizontal and angular velocity smaller than 7o/s in 86.7%. 59% had some kind of influence caused by the caloric test NEOF as inversion, hyporeflexia, hyperreflexia, nystagmus directional preponderance (NDP and labyrinthine preponderance (LP changed. The most prevalent findings were normal vestibular tests (EVN and bilateral irritative peripheral vestibular syndrome (BIPVS. 38.7% caloric ice and realized these cases it was possible to reach a conclusion in 79%. Conclusion: The NEOF most common was the horizontal type, with VACL less than 7o/s, influencing the majority of examinations and only the results of caloric testing the air, with reversal of post-caloric nystagmus, hyperreflexia and hyporeflexia, NDP and PL altered; the findings were more prevalent and BIPVS EVN, and the caloric test the influence of ice withdrew NEOF in most individuals, enabling to reach a final conclusion.

Bilateral Facial Paralysis Caused by Bilateral Temporal Bone Fracture: A Case Report and a Literature Review

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Sultan Şevik Eliçora

2015-01-01

Full Text Available Bilateral facial paralysis caused by bilateral temporal bone fracture is a rare clinical entity, with seven cases reported in the literature to date. In this paper, we describe a 40-year-old male patient with bilateral facial paralysis and hearing loss that developed after an occupational accident. On physical examination, House-Brackmann (HB facial paralysis of grade 6 was observed on the right side and HB grade 5 paralysis on the left. Upon temporal bone computed tomography (CT examination, a fracture line exhibiting transverse progression was observed in both petrous temporal bones. Our patient underwent transmastoid facial decompression surgery of the right ear. The patient refused a left-side operation. Such patients require extensive monitoring in intensive care units because the presence of multiple injuries means that facial functions are often very difficult to evaluate. Therefore, delays may ensue in both diagnosis and treatment of bilateral facial paralysis.

Vestibular Function in Adults With Epilepsy of Unknown Etiology.

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Hamed, Sherifa A; Tohamy, Amal M; Oseilly, Amira M

2017-09-01

This study aimed to evaluate vestibular function in adults with chronic epilepsy of unknown etiology in the inter-ictal period. Epilepsy is a chronic medical disorder. Life-long therapy may be required in one-third of patients. Epilepsy is associated with comorbid somatic conditions which impairs patients' quality of life. This cross-sectional study included 28 with generalized tonic clonic (GTC) convulsions and 14 and 3 with temporal (TLE) and frontal lobe (FLE) epilepsies with secondary generalization (all were on regular carbamazepine therapy) and 40 healthy control subjects. The patients' mean age was 34.97 ± 7.35 years and the duration of illness was 18.75 ± 7.99 years. All underwent videonystagmography (VNG). Compared with controls, patients had frequent vestibular symptoms including dizziness (62.22%) (p = 0.0001) and sense of imbalance (44.44%) (p = 0.0001). Eleven patients (24.44%) had central vestibular dysfunction (p = 0.0001); 9 (20%) had mixed vestibular dysfunction and one (2.22%) had peripheral vestibular dysfunction (p = 0.0001). Abnormalities were observed in saccadic (44.4%) and pursuit (42.2%) eye movements, optokinetic nystagmus (42.2%) and positioning/positional (11.11%) and caloric (13.33%) testing. TLE and FLE were associated with more VNG abnormalities than GTC. No significant differences were observed in the demographic and clinical characteristics between patients with and without VNG abnormalities. Vestibular manifestations are frequent in patients with epilepsy. This may be a result of the permanent damaging effect of chronic epilepsy on the vestibular cortical areas and/or a toxic effect from prolonged carbamazepine therapy on the peripheral and central vestibular systems.

Distinct spontaneous shrinkage of a sporadic vestibular schwannoma

DEFF Research Database (Denmark)

Huang, Xiaowen; Cayé-Thomasen, Per; Stangerup, Sven-Eric

2013-01-01

on "shrinkage" or "negative growth" or "regression" or "involution" of the tumor were selected, and the contents on the rate, extent and mechanism of spontaneous tumor shrinkage were extracted and reviewed. The reported rate of spontaneous shrinkage of vestibular schwannoma is 5-10% of patients managed......We present a case with outspoken spontaneous vestibular schwannoma shrinkage and review the related literature. The patient was initially diagnosed with a left-sided, intrameatal vestibular schwannoma, which subsequently grew into the cerebello-pontine angle (CPA), followed by total shrinkage...... of the CPA component without any intervention over a 12-year observation period. The literature on spontaneous tumor shrinkage was retrieved by searching the subject terms "vestibular schwannoma, conservative management" in PubMed/MEDLINE database, without a time limit. Of the published data, the articles...

Origin of vestibular dysfunction in Usher syndrome type 1B.

NARCIS (Netherlands)

Sun, J.; Alphen, A.M. van; Wagenaar, M.; Huygen, P.L.M.; Hoogenraad, C.C.; Hasson, T.; Koekkoek, S.K.; Bohne, B.A.; Zeeuw, C.I. de

2001-01-01

It is still debated to what extent the vestibular deficits in Usher patients are due to either central vestibulocerebellar or peripheral vestibular problems. Here, we determined the origin of the vestibular symptoms in Usher 1B patients by subjecting them to compensatory eye movement tests and by

The prevalence of vestibular symptoms in migraine or tension-type headache.

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Akdal, Gülden; Ozge, Aynur; Ergör, Gül

2013-01-01

We assessed frequency of vestibular symptoms in Headache Clinic patients over 10 years. A descriptive study of 5111 consecutive patients with tension-type headache or migraine, analyzed for dizziness/ vertigo accompanying headache and for a lifetime history of motion-sickness, cyclic vomiting, recurrent abdominal pain or atopy. Migraine patients were re-grouped as those with vestibular symptoms (dizziness/vertigo or motion sickness) and those without and their data then re-analyzed. There were 1880 migraine patients and 3231 tension-type headache patients. Significantly more migraine patients than tension-type headache patients experienced vestibular symptoms (p< 0.0001). The migraine with vestibular symptoms group was significantly younger (p< 0.05) had more aura, more phonophobia with migraine attacks (p< 0.0001). Menstruation and reported sleep problems impacted on headaches. While past history of cyclical vomiting, recurrent abdominal pain or atopy was about twice as common in migraine with aura and it was also more common in migraine with vestibular symptoms than migraine without vestibular symptoms. Vestibular symptoms are common in migraine patients. Migraine with vestibular symptoms might constitute a special group, one more likely to have had cyclic vomiting, recurrent abdominal pain or atopy.

Successful treatment of bilateral visual loss caused by HIV-associated optic neuritis

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Claire Cullen

2011-12-01

Full Text Available Optic neuritis is not an uncommon diagnosis in HIV-infected patients, but it is rarely idiopathic. We report a case of a young HIV-infected woman who developed optic neuritis as her presenting manifestation of HIV infection. She had initially experienced sudden-onset right-sided painful visual loss; the left eye had become involved within days. Bilateral swollen discs were apparent on fundoscopy. Investigations were performed for meningitis (including bacterial, cryptococcal, tuberculous and syphilitic types, auto-immune diseases, toxoplasma, rubella, cytomegalovirus, viral hepatitis, HTLV-1/2, HIV-1/2 and syphilis. The only positive result was a reactive HIV enzyme-linked immunosorbent assay. The CD4 count was 85 cells/µl. A post-contrast magnetic resonance imaging scan of the brain illustrated enhancement of the optic nerves. Treatment was 3 days of intravenous methylprednisolone 1 g daily, followed by 11 days of oral prednisone 60 mg daily. Highly active antiretroviral therapy was initiated after 2 weeks. Vision improved from day 6 after commencement of steroid therapy, with ongoing recovery at 5 months.

Sudden bilateral sensorineural hearing loss after intravenous cocaine injection: a case report and review of the literature.

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Stenner, Markus; Stürmer, Konrad; Beutner, Dirk; Klussmann, Jens Peter

2009-12-01

Little is known about the effects of intravenous abuse of cocaine, especially on the inner ear. We report on a 26-year-old man who presented to our outpatient department with a sudden severe hearing loss after intravenous injection of cocaine. The audiogram on admission showed symmetric air conduction levels up to 80 dB at 4 kHz. After treatment with intravenous sodium chloride, prednisolone, and pentoxifylline, the audiogram 2 days later showed a bilateral normacusis. A review of the literature on the topic is given and possible reasons for inner ear damages caused by cocaine are discussed.

ECT and memory loss.

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Squire, L R

1977-09-01

The author reviews several studies that clarify the nature of the memory loss associated with ECT. Bilateral ECT produced greater anterograde memory loss than right unilateral ECT and more extensive retrograde amnesia than unilateral ECT. Reactivating memories just before ECT did not produce amnesia. Capacity for new learning recovered substantially by several months after ECT, but memory complaints were common in individuals who had received bilateral ECT. Other things being equal, right unilateral ECT seems preferable to bilateral ECT because the risks to memory associated with unilateral ECT are smaller.

Evidence for cognitive vestibular integration impairment in idiopathic scoliosis patients

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Mercier Pierre

2009-08-01

Full Text Available Abstract Background Adolescent idiopathic scoliosis is characterized by a three-dimensional deviation of the vertebral column and its etiopathogenesis is unknown. Various factors cause idiopathic scoliosis, and among these a prominent role has been attributed to the vestibular system. While the deficits in sensorimotor transformations have been documented in idiopathic scoliosis patients, little attention has been devoted to their capacity to integrate vestibular information for cognitive processing for space perception. Seated idiopathic scoliosis patients and control subjects experienced rotations of different directions and amplitudes in the dark and produced saccades that would reproduce their perceived spatial characteristics of the rotations (vestibular condition. We also controlled for possible alteration of the oculomotor and vestibular systems by measuring the subject's accuracy in producing saccades towards memorized peripheral targets in absence of body rotation and the gain of their vestibulo-ocular reflex. Results Compared to healthy controls, the idiopathic scoliosis patients underestimated the amplitude of their rotations. Moreover, the results revealed that idiopathic scoliosis patients produced accurate saccades to memorized peripheral targets in absence of body rotation and that their vestibulo-ocular reflex gain did not differ from that of control participants. Conclusion Overall, results of the present study demonstrate that idiopathic scoliosis patients have an alteration in cognitive integration of vestibular signals. It is possible that severe spine deformity developed partly due to impaired vestibular information travelling from the cerebellum to the vestibular cortical network or alteration in the cortical mechanisms processing the vestibular signals.

Morphological analysis of the vestibular aqueduct by computerized tomography images

International Nuclear Information System (INIS)

Marques, Sergio Ricardo; Smith, Ricardo Luiz; Isotani, Sadao; Alonso, Luis Garcia; Anadao, Carlos Augusto; Prates, Jose Carlos; Lederman, Henrique Manoel

2007-01-01

Objective: In the last two decades, advances in the computerized tomography (CT) field revise the internal and medium ear evaluation. Therefore, the aim of this study is to analyze the morphology and morphometric aspects of the vestibular aqueduct on the basis of computerized tomography images (CTI). Material and method: Computerized tomography images of vestibular aqueducts were acquired from patients (n = 110) with an age range of 1-92 years. Thereafter, from the vestibular aqueducts images a morphometric analysis was performed. Through a computerized image processing system, the vestibular aqueduct measurements comprised of its area, external opening, length and the distance from the vestibular aqueduct to the internal acoustic meatus. Results: The morphology of the vestibular aqueduct may be funnel-shaped, filiform or tubular and the respective proportions were found to be at 44%, 33% and 22% in children and 21.7%, 53.3% and 25% in adults. The morphometric data showed to be of 4.86 mm 2 of area, 2.24 mm of the external opening, 4.73 mm of length and 11.88 mm of the distance from the vestibular aqueduct to the internal acoustic meatus, in children, and in adults it was of 4.93 mm 2 , 2.09 mm, 4.44 mm, and 11.35 mm, respectively. Conclusions: Computerized tomography showed that the vestibular aqueduct presents high morphological variability. The morphometric analysis showed that the differences found between groups of children and adults or between groups of both genders were not statistically significant

Hoxb1 controls anteroposterior identity of vestibular projection neurons.

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Yiju Chen

Full Text Available The vestibular nuclear complex (VNC consists of a collection of sensory relay nuclei that integrates and relays information essential for coordination of eye movements, balance, and posture. Spanning the majority of the hindbrain alar plate, the rhombomere (r origin and projection pattern of the VNC have been characterized in descriptive works using neuroanatomical tracing. However, neither the molecular identity nor developmental regulation of individual nucleus of the VNC has been determined. To begin to address this issue, we found that Hoxb1 is required for the anterior-posterior (AP identity of precursors that contribute to the lateral vestibular nucleus (LVN. Using a gene-targeted Hoxb1-GFP reporter in the mouse, we show that the LVN precursors originate exclusively from r4 and project to the spinal cord in the stereotypic pattern of the lateral vestibulospinal tract that provides input into spinal motoneurons driving extensor muscles of the limb. The r4-derived LVN precursors express the transcription factors Phox2a and Lbx1, and the glutamatergic marker Vglut2, which together defines them as dB2 neurons. Loss of Hoxb1 function does not alter the glutamatergic phenotype of dB2 neurons, but alters their stereotyped spinal cord projection. Moreover, at the expense of Phox2a, the glutamatergic determinants Lmx1b and Tlx3 were ectopically expressed by dB2 neurons. Our study suggests that the Hox genes determine the AP identity and diversity of vestibular precursors, including their output target, by coordinating the expression of neurotransmitter determinant and target selection properties along the AP axis.

Pediatric tinnitus: Incidence of imaging anomalies and the impact of hearing loss.

Science.gov (United States)

Kerr, Rhorie; Kang, Elise; Hopkins, Brandon; Anne, Samantha

2017-12-01

Guidelines exist for evaluation and management of tinnitus in adults; however lack of evidence in children limits applicability of these guidelines to pediatric patients. Objective of this study is to determine the incidence of inner ear anomalies detected on imaging studies within the pediatric population with tinnitus and evaluate if presence of hearing loss increases the rate of detection of anomalies in comparison to normal hearing patients. Retrospective review of all children with diagnosis of tinnitus from 2010 to 2015 ;at a tertiary care academic center. 102 pediatric patients with tinnitus were identified. Overall, 53 patients had imaging studies with 6 abnormal findings (11.3%). 51/102 patients had hearing loss of which 33 had imaging studies demonstrating 6 inner ear anomalies detected. This is an incidence of 18.2% for inner ear anomalies identified in patients with hearing loss (95% confidence interval (CI) of 7.0-35.5%). 4 of these 6 inner ear anomalies detected were vestibular aqueduct abnormalities. The other two anomalies were cochlear hypoplasia and bilateral semicircular canal dysmorphism. 51 patients had no hearing loss and of these patients, 20 had imaging studies with no inner ear abnormalities detected. There was no statistical difference in incidence of abnormal imaging findings in patients with and without hearing loss (Fisher's exact test, p ;= ;0.072.) CONCLUSION: There is a high incidence of anomalies detected in imaging studies done in pediatric patients with tinnitus, especially in the presence of hearing loss. Copyright © 2017 Elsevier B.V. All rights reserved.

A Case Report of Unilateral Severe Visual Loss Along with Bilateral Optic Disc Cupping Secondary to Metastatic Brain Tumor

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M Mahdavi

2006-07-01

Full Text Available Purpose: To report a case of unilateral severe visual loss and bilateral optic disc cupping secondary to brain metastasis of bronchogenic carcinoma Patient and findings: A 48 year-old woman presented with severe visual loss of left eye without redness or pain or any systemic findings .Clinical findings included decreased visual acuity of left eye to 4 m CF and (+3 positive Marcus-Gunn reflex .There was asymmetric optic disc cupping associated with visual field defect in left eye The neurologic investigations showed a secondary metastatic tumor in the brain from bronchogenic carcinoma. Conclusion: Before making a diagnosis of normal -tension glaucoma in asymmetric optic disc cupping and normal intraocular pressure, ophthalmologists should rule out neurologic defects and brain tumors.

Interaural difference values of vestibular evoked myogenic.

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Marziyeh Moallemi

2015-01-01

Full Text Available Migraine is a neurologic disease, which often is associated with a unilateral headache. Vestibular abnormalities are common in migraine. Vestibular evoked myogenic potentials (VEMPs assess otolith function in particular functional integrity of the saccule and the inferior vestibular nerve. We used VEMP to evaluate if the migraine headache can affect VEMP asymmetry parameters. A total of 25 patients with migraine (22 females and 3 males who were diagnosed according to the criteria of IHS-1988 were enrolled in this cross-sectional study. Control group consisted of 26 healthy participants (18 female and 8 male, without neurotological symptoms and history of migraine. The short tone burst (95 dB nHL, 500 Hz was presented to ears. VEMP was recorded with surface electromyography over the contracted ipsilateral sternocleidomastoid (SCM muscle. Although current results showed that the amplitude ratio is greater in migraine patients than normal group, there was no statistical difference between two groups in mean asymmetry parameters of VEMP. Asymmetry measurements in vestibular evoked myogenic potentials probably are not indicators of unilateral deficient in saccular pathways of migraine patients.

Isolation and culture of adult mouse vestibular nucleus neurons

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Him, Aydın; Altuntaş, Serap; Öztürk, Gürkan; Erdoğan, Ender; Cengiz, Nureddin

2017-12-19

Background/aim: Isolated cell cultures are widely used to study neuronal properties due to their advantages. Although embryonic animals are preferred for culturing, their morphological or electrophysiological properties may not reflect adult neurons, which may be important in neurodegenerative diseases. This paper aims to develop a method for preparing isolated cell cultures of medial vestibular nucleus (MVN) from adult mice and describe its morphological and electrophysiological properties.Materials and methods: Vestibular nucleus neurons were mechanically and enzymatically isolated and cultured using a defined medium with known growth factors. Cell survival was measured with propidium iodide, and electrophysiological properties were investigated with current-clamp recording.Results: Vestibular neurons grew neurites in cultures, gaining adult-like morphological properties, and stayed viable for 3 days in culture. Adding bovine calf serum, nerve growth factor, or insulin-like growth factor into the culture medium enhanced neuronal viability. Current-clamp recording of the cultured neurons revealed tonic and phasic-type neurons with similar input resistance, resting membrane potential, action potential amplitude, and duration. Conclusion: Vestibular neurons from adult mice can be cultured, and regenerate axons in a medium containing appropriate growth factors. Culturing adult vestibular neurons provides a new method to study age-related pathologies of the vestibular system.

A review of the interrelationship between vestibular dysfunction ...

African Journals Online (AJOL)

functions, the effect of rehabilitation focused on the functioning of a specific canal, and the effect of different rehabilitation programmes on different vestibular deficiencies are suggested. Keywords: Vestibular dysfunction; Motor development; Learning disabilities; Posture; Rehabilitation and exercises. South African Journal ...

Hearing Loss due to Carbon Monoxide Poisoning

DEFF Research Database (Denmark)

Mehrparvar, Amir Houshang; Davari, Mohammad Hossein; Mollasadeghi, Abolfazl

2013-01-01

Carbon monoxide poisoning is one of the rare causes of hearing loss which may cause reversible or irreversible, unilateral or bilateral hearing loss after acute or chronic exposure. In this report, we present a case of bilateral sensorineural hearing loss in a secondary smelting workshop worker a...

Cross-Modal Calibration of Vestibular Afference for Human Balance.

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Martin E Héroux

Full Text Available To determine how the vestibular sense controls balance, we used instantaneous head angular velocity to drive a galvanic vestibular stimulus so that afference would signal that head movement was faster or slower than actual. In effect, this changed vestibular afferent gain. This increased sway 4-fold when subjects (N = 8 stood without vision. However, after a 240 s conditioning period with stable balance achieved through reliable visual or somatosensory cues, sway returned to normal. An equivalent galvanic stimulus unrelated to sway (not driven by head motion was equally destabilising but in this situation the conditioning period of stable balance did not reduce sway. Reflex muscle responses evoked by an independent, higher bandwidth vestibular stimulus were initially reduced in amplitude by the galvanic stimulus but returned to normal levels after the conditioning period, contrary to predictions that they would decrease after adaptation to increased sensory gain and increase after adaptation to decreased sensory gain. We conclude that an erroneous vestibular signal of head motion during standing has profound effects on balance control. If it is unrelated to current head motion, the CNS has no immediate mechanism of ignoring the vestibular signal to reduce its influence on destabilising balance. This result is inconsistent with sensory reweighting based on disturbances. The increase in sway with increased sensory gain is also inconsistent with a simple feedback model of vestibular reflex action. Thus, we propose that recalibration of a forward sensory model best explains the reinterpretation of an altered reafferent signal of head motion during stable balance.

Otolith-Canal Convergence In Vestibular Nuclei Neurons

Science.gov (United States)

Dickman, J. David; Si, Xiao-Hong

2002-01-01

The current final report covers the period from June 1, 1999 to May 31, 2002. The primary objective of the investigation was to determine how information regarding head movements and head position relative to gravity is received and processed by central vestibular nuclei neurons in the brainstem. Specialized receptors in the vestibular labyrinths of the inner ear function to detect angular and linear accelerations of the head, with receptors located in the semicircular canals transducing rotational head movements and receptors located in the otolith organs transducing changes in head position relative to gravity or linear accelerations of the head. The information from these different receptors is then transmitted to central vestibular nuclei neurons which process the input signals, then project the appropriate output information to the eye, head, and body musculature motor neurons to control compensatory reflexes. Although a number of studies have reported on the responsiveness of vestibular nuclei neurons, it has not yet been possible to determine precisely how these cells combine the information from the different angular and linear acceleration receptors into a correct neural output signal. In the present project, rotational and linear motion stimuli were separately delivered while recording responses from vestibular nuclei neurons that were characterized according to direct input from the labyrinth and eye movement sensitivity. Responses from neurons receiving convergent input from the semicircular canals and otolith organs were quantified and compared to non-convergent neurons.

Bilateral spontaneous hemotympanum: Case report

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Economou Nicolas C

2006-10-01

Full Text Available Abstract Background The most common causes of hemotympanum are therapeutic nasal packing, epistaxis, blood disorders and blunt trauma to the head. Hemotympanum is characterized as idiopathic, when it is detected in the presence of chronic otitis media. A rare case of spontaneous bilateral hemotympanum in a patient treated with anticoagulants is presented herein. Case presentation A 72-year-old male presented with acute deterioration of hearing. In the patient's medical history aortic valve replacement 1 year before presentation was reported. Since then he had been administered regularly coumarinic anticoagulants, with INR levels maintained between 3.4 and 4.0. Otoscopy revealed the presence of bilateral hemotympanum. The audiogram showed symmetrical moderately severe mixed hearing loss bilaterally, with the conductive component predominating. Tympanograms were flat bilaterally with absent acoustic reflexes. A computerized tomography scan showed the presence of fluid in the mastoid and middle ear bilaterally. Treatment was conservative and consisted of a 10-day course of antibiotics, anticongestants and temporary interruption of the anticoagulant therapy. After 3 weeks, normal tympanic membranes were found and hearing had returned to previous levels. Conclusion Anticoagulant intake should be included in the differential diagnosis of hemotympanum, because its detection and appropriate treatment may lead to resolution of the disorder.

Vestibular signals in primate cortex for self-motion perception.

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Gu, Yong

2018-04-21

The vestibular peripheral organs in our inner ears detect transient motion of the head in everyday life. This information is sent to the central nervous system for automatic processes such as vestibulo-ocular reflexes, balance and postural control, and higher cognitive functions including perception of self-motion and spatial orientation. Recent neurophysiological studies have discovered a prominent vestibular network in the primate cerebral cortex. Many of the areas involved are multisensory: their neurons are modulated by both vestibular signals and visual optic flow, potentially facilitating more robust heading estimation through cue integration. Combining psychophysics, computation, physiological recording and causal manipulation techniques, recent work has addressed both the encoding and decoding of vestibular signals for self-motion perception. Copyright © 2018. Published by Elsevier Ltd.

Bilateral cochlear implantation: current concepts, indications, and results.

Science.gov (United States)

Basura, Gregory J; Eapen, Rose; Buchman, Craig A

2009-12-01

The optimal treatment for bilateral hearing loss continues to evolve as cochlear implant (CI) and hearing aid technologies advance, as does our understanding of the central auditory system. Ongoing discussions continue on the validity and feasibility of bilateral CI in terms of performance, justification of need, medical/surgical safety concerns, and economics. The purpose of this review article is to provide an update on the advantages and disadvantages of bilateral CI and to provide a discussion on timing (simultaneous vs. sequential), technology (bimodal vs. binaural) and feasibility. Binaural advantages are found in both adult and pediatric bilateral CI recipients, the greatest being the head shadow effect and improvements in localization and loudness summation. This theoretically offers an advantage over their unilateral implanted counterparts in terms of improved sound localization and enhanced speech perception under noisy conditions. Most investigators agree that bilateral stimulation during critical periods of development is paramount for optimizing auditory functioning in children. Currently, bilateral CI is widely accepted as a safe and effective means of bilateral auditory stimulation.

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

International Nuclear Information System (INIS)

Vignaux, G.; Chabbert, C.; Gaboyard-Niay, S.; Travo, C.; Machado, M.L.; Denise, P.; Comoz, F.; Hitier, M.; Landemore, G.; Philoxène, B.; Besnard, S.

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.

Influence of cochlear implantation on peripheral vestibular receptor function.

Science.gov (United States)

Krause, Eike; Louza, Julia P R; Wechtenbruch, Juliane; Gürkov, Robert

2010-06-01

The objectives of this study were 1) to assess the influence of a cochlear implantation on peripheral vestibular receptor function in the inner ear in the implant and in the nonimplant side, and 2) to analyze a possible correlation with resulting vertigo symptoms. Prospective clinical study. Cochlear implant center at tertiary referral hospital. A total of 32 patients, aged 15 to 83 years, undergoing cochlear implantation were assessed pre- and postoperatively for caloric horizontal semicircular canal response and vestibular-evoked myogenic potentials of the sacculus, and postoperatively for subjective vertigo symptoms. Patients with vertigo were compared with patients without symptoms with regard to the findings of the vestibular function tests. Cochlear implantation represents a significant risk factor for horizontal semicircular canal impairment (P 0.05). Cochlear implantation is a relevant risk factor for damage of peripheral vestibular receptor function. Therefore, preservation not only of residual hearing function but also of vestibular function should be aimed for, by using minimally invasive surgical techniques. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

Vestibular evoked myogenic potential testing for the diagnosis of conductive hearing loss: survey of pediatric otolaryngologists' knowledge and beliefs.

Science.gov (United States)

Dargie, Jenna M; Zhou, Guangwei; Dornan, Briana K; Whittemore, Kenneth R

2014-11-01

To assess physicians' knowledge and beliefs regarding vestibular evoked myogenic potential (VEMP) testing in children. A survey was delivered via email in html format to 1069 members of the American Academy of Otolaryngology--Head and Neck Surgery who identified as pediatric otolaryngologists. Study data were collected and managed using the Research Electronic Data Capture (REDCap) tools. 443 (41.4%) physicians opened the email. 190 (42.9% of opens) initiated the survey, of which 117 (61.9%) fully completed the survey of the physicians who responded to a question regarding knowledge of VEMP, 16% of respondents had never heard of the test. 16% of participants would use it in the setting of diagnosing pediatric conductive hearing loss. Responses regarding the youngest age at which VEMP is possible ranged from younger than 6 months through greater than 13 years of age. Beliefs regarding utility and reliability of VEMP varied, with 'unsure' as the most frequent response. Additionally, only 26% of pediatric otolaryngologists indicated some access to the test. The knowledge and availability of VEMP testing in the pediatric otolaryngology community varies widely. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Potencial evocado miogênico vestibular a baixas frequências de estimulação Vestibular evoked myogenic potentials using low frequency stimuli

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Aline Cabral de Oliveira

2011-12-01

Full Text Available Os potenciais evocados miogênicos vestibulares são reflexos vestíbulo-cervicais, decorrentes da estimulação do sáculo com sons de forte intensidade. São necessários parâmetros de normalidade para indivíduos jovens normais, utilizando-se estímulos a baixas frequências, as quais configuram a região de maior sensibilidade desse órgão sensorial. OBJETIVO: Realizar normatização do potencial evocado miogênico vestibular para baixas frequências de estimulação. MATERIAL E MÉTODO: Captou-se o potencial evocado miogênico vestibular em 160 orelhas, no músculo esternocleidomastoideo, de forma ipsilateral, por meio da promediação de 200 tone bursts, frequência de 250 Hz, intensidade de 95 dB NAn. FORMA DE ESTUDO: Estudo de coorte contemporânea com corte transversal. RESULTADOS: Aplicando-se o teste T de Student ou o Teste de Mann-Whitney, não foi constatada diferença significativa para parâmetros do potencial evocado miogênico vestibular entre os gêneros, para p Vestibular evoked myogenic potentials are vestibulocervical reflexes resulting from sacculus stimulation with strong intensity sounds. Normality parameters are necessary for young normal individuals, using low frequency stimuli, which configure the most sensitive region of this sensory organ. AIM: To establish vestibular evoked myogenic potential standards for low frequency stimulation. MATERIAL AND METHOD: Vestibular evoked myogenic potential was captured from 160 ears, in the ipsilateral sternocleidomastoid muscle, using 200 averaged tone-burst stimuli, at 250 Hz, with an intensity of 95 dB NAn. CASE STUDY: Clinical observational cross-sectional. RESULTS: Neither the student's t-test nor the Mann-Whitney test showed a significant difference in latency or vestibular evoked myogenic potential amplitudes, for p <; 0.05. Irrespective of gender, we found latencies of p13-n23 and p13-n23 interpeaks of 13.84 ms (± 1.41, 23.81 ms (±1.99 and 10.62 ms (± 6.56, respectively

Morphology and electrophysiology of the vestibular organ in the guinea pig

NARCIS (Netherlands)

Oei, Markus Lee Yang Murti

2003-01-01

To obtain more information about the anatomy and function of the vestibular organ in normal and pathological conditions, evaluation methods are needed. For experimental purposes, the vestibular organ of the guinea pig is often used as a model for the human vestibular organ. The purpose of the

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.

Vestibular migraine: clinical and epidemiological aspects

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Ligia Oliveira Gonçalves Morganti

Full Text Available ABSTRACT INTRODUCTION: Vestibular migraine (VM is one of the most often common diagnoses in neurotology, but only recently has been recognized as a disease. OBJECTIVE: To analyze the clinical and epidemiological profile of patients with VM. METHODS: This was a retrospective, observational, and descriptive study, with analysis of patients' records from an outpatient VM clinic. RESULTS: 94.1% of patients were females and 5.9% were males. The mean age was 46.1 years; 65.6% of patients had had headache for a longer period than dizziness. A correlation was detected between VM symptoms and the menstrual period. 61.53% of patients had auditory symptoms, with tinnitus the most common, although tonal audiometry was normal in 68.51%. Vectoelectronystagmography was normal in 67.34%, 10.20% had hyporeflexia, and 22.44% had vestibular hyperreflexia. Electrophysiological assessment showed no abnormalities in most patients. Fasting plasma glucose and glycemic curve were normal in most patients, while the insulin curve was abnormal in 75%. 82% of individuals with MV showed abnormalities on the metabolism of carbohydrates. CONCLUSION: VM affects predominantly middle-aged women, with migraine headache representing the first symptom, several years before vertigo. Physical, auditory, and vestibular evaluations are usually normal. The most frequent vestibular abnormality was hyperreflexia. Most individuals showed abnormality related to carbohydrate metabolism.

A neurofibromatosis type 2 case with vestibular, trigeminal and facial schwannomas together: magnetic resonance imaging findings

International Nuclear Information System (INIS)

Akay, S.; Hamcan, S.; Kara, K.; Battal, B.; Tasar, M.

2012-01-01

Full text: Introduction: Neurofibromatosis type 2 (NF2) is characterized by the development of multiple nervous system tumors. This disorder is also called multiple inherited schwannomas (MIS), meningiomas (M), and ependymomas (E) (MISME) syndrome. Objectives and tasks: To discuss the magnetic resonance (MR) imaging findings of a NF2 case who has bilateral vestibular and trigeminal schwannomas, unilateral facial schwannoma, multiple meningiomas and cervical intramedullary spinal cord tumors. Materials and methods: A 23-year-old male patient complaining of tinnitus and imbalance for 3 years, came to Neck-Nose-Throat department of our hospital. After the physical examination, the patient was referred to our department for the further work up with MR imaging. Results: Brain MR imaging showed bilateral acoustic schwannoma which reach through the internal acoustic canals. Bilateral symmetric homogeneously enhanced masses were also detected in Meckel's caves. Similarly, one milimetric enhancing lesion was seen at the right facial nerve. Eight meningiomas in various locations were observed, as well. Additionally, two enhancing intramedullary well-defined small foci were detected in the proximal cervical spinal cord. Ependymomas or intraparanchimal schwannomas were primarily suspected. Conclusion: This case includes all the probable intracranial and spinal mass lesions which may be associated with NF2. Enhanced MR is very reliable imaging modality for the detailed evaluation of NF2 patients

A neurofibromatosis type 2 case with vestibular, trigeminal and facial schwannomas together: magnetic resonance imaging findings

Energy Technology Data Exchange (ETDEWEB)

Akay, S; Hamcan, S; Kara, K; Battal, B; Tasar, M

2012-07-01

Full text: Introduction: Neurofibromatosis type 2 (NF2) is characterized by the development of multiple nervous system tumors. This disorder is also called multiple inherited schwannomas (MIS), meningiomas (M), and ependymomas (E) (MISME) syndrome. Objectives and tasks: To discuss the magnetic resonance (MR) imaging findings of a NF2 case who has bilateral vestibular and trigeminal schwannomas, unilateral facial schwannoma, multiple meningiomas and cervical intramedullary spinal cord tumors. Materials and methods: A 23-year-old male patient complaining of tinnitus and imbalance for 3 years, came to Neck-Nose-Throat department of our hospital. After the physical examination, the patient was referred to our department for the further work up with MR imaging. Results: Brain MR imaging showed bilateral acoustic schwannoma which reach through the internal acoustic canals. Bilateral symmetric homogeneously enhanced masses were also detected in Meckel's caves. Similarly, one milimetric enhancing lesion was seen at the right facial nerve. Eight meningiomas in various locations were observed, as well. Additionally, two enhancing intramedullary well-defined small foci were detected in the proximal cervical spinal cord. Ependymomas or intraparanchimal schwannomas were primarily suspected. Conclusion: This case includes all the probable intracranial and spinal mass lesions which may be associated with NF2. Enhanced MR is very reliable imaging modality for the detailed evaluation of NF2 patients.

Combat-incurred bilateral transfemoral limb loss: a comparison of the Vietnam War to the wars in Afghanistan and Iraq.

Science.gov (United States)

Dougherty, Paul J; McFarland, Lynne V; Smith, Douglas G; Reiber, Gayle E

2012-12-01

This study is a comparison of the self-reported health status, quality of life, function, and prosthetic use of veterans with bilateral transfemoral limb loss following combat injury in either the Vietnam War or the recent conflicts in Afghanistan and Iraq, to learn what improvements in surgery, prosthetics, and rehabilitation have occurred. Subjects were identified from Veteran's Administration and military databases. A cross-sectional survey was conducted of service members with bilateral transfemoral amputation who participated in a larger survey of service members with any type of amputation associated with a battlefield injury from the Vietnam War or Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF). The survey was conducted by mail, telephone, or Web site during 2007 to 2008. There were 501 subjects in the Vietnam group and 541 in the OIF/OEF group with any type of limb loss. Bilateral transfemoral amputation was reported in 23 (7.7%) of 298 of the Vietnam group and 10 (3.5%) of 283 of the OIF/OEF group (χ test, p = 0.04). Self-reported health status was rated as good to excellent in 40% of the Vietnam group and 80% in the OIF/OEF group (p = 0.04). Quality of life was rated as good to excellent in 54.6% of the Vietnam group and 70% of the OIF/OEF group (not significant). Wheelchair use is reported by 22 of 23 subjects in the Vietnam group and all of the subjects of the OIF/OEF group. Of the Vietnam group, 8 (34.7%) of 23 currently use prostheses versus 7 (70%) of 10 of the OIF/OEF group (χ test, p = 0.13). The mean (SD) number of prostheses currently used is 1.0 (1.9) for the Vietnam group and 4.0 (5.2) for the OIF/OEF group (p = 0.022). Participants who served in OIF/OEF and those who served in Vietnam report comparable quality of life. Prosthetic use continues to be a problem, especially as the service member ages. Epidemiologic study, level III.

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.

Atypical Wernicke′s syndrome sans encephalopathy with acute bilateral vision loss due to post-chiasmatic optic tract edema

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Soaham Dilip Desai

2014-01-01

Full Text Available A middle aged male presented with acute bilateral vision loss, 4 weeks after undergoing gastric bypass surgery for gastric carcinoma. He had normal sensorium, fundoscopy, normal pupillary reaction to light, but had mild opthalmoparesis and nystagmus with ataxia. Magnetic resonance imaging of the brain revealed post-chiasmatic optic tract edema along with other classical features of Wernicke′s syndrome. Thiamine supplementation leads to complete resolution of clinical as well as imaging findings. In appropriate clinical settings, a high index of suspicion and early treatment are essential for managing Wernicke′s syndrome even in patients with atypical clinical and imaging presentation.

Impedance pattern of vaginal and vestibular mucosa in cyclic goats

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Ivo Křivánek

2008-01-01

Full Text Available The changes of vaginal and vestibular impedance during the oestrous cycle in goats were examined. The onset of oestrus was teased with a buck once a day during the experiment. Impedance was mea­sured by a four-terminal method. The vaginal impedance was recorded under slight pressure of electrodes to the vaginal dorsal wall at the cervix. The vestibular impedance was recorded under slight pressure of electrodes to the vestibular dorsal wall 5 cm from the vulva and at the vulva. The im­pe­dan­ce was measured once a day from 4 days before the expected oestrus to 6 days after onset of oestrus. The vaginal impedance at the cervix decreased during pro-oestrus (P < 0.01 and increased du­ring oestrus (P < 0.01. The vestibular impedance 5 cm from the vulva decreased during pro-oestrus (P < 0.01 and increased after oestrus (P < 0.01. The decrease of vaginal impedance during peri-oestrus was nearly twofold in comparison with the vestibular impedance 5 cm from the vulva. No sig­ni­fi­cant decrease of the vestibular impedance at the vulva was found during the oestrous cycle. The results indicate that the vaginal impedance at the cervix and vestibular impedance 5 cm from the vulva measured by means of a four-terminal method during the oestrous cycle display cyclic changes that are closely related to the oestrous behaviour of goats.

Open-Fit Domes and Children with Bilateral High-Frequency Sensorineural Hearing Loss: Benefits and Outcomes.

Science.gov (United States)

Johnstone, Patti M; Yeager, Kelly R; Pomeroy, Marnie L; Hawk, Nicole

2018-04-01

Open-fit domes (OFDs) coupled with behind-the-ear (BTE) hearing aids were designed for adult listeners with moderate-to-severe bilateral high-frequency hearing loss (BHFL) with little to no concurrent loss in the lower frequencies. Adult research shows that BHFL degrades sound localization accuracy (SLA) and that BTE hearing aids with conventional earmolds (CEs) make matters worse. In contrast, research has shown that OFDs enhance spatial hearing percepts in adults with BHFL. Although the benefits of OFDs have been studied in adults with BHFL, no published studies to date have investigated the use of OFDs in children with the same hearing loss configuration. This study seeks to use SLA measurements to assess efficacy of bilateral OFDs in children with BHFL. To measure SLA in children with BHFL to determine the extent to which hearing loss, age, duration of CE use, and OFDs affect localization accuracy. A within-participant experimental design using repeated measures was used to determine the effect of OFDs on localization accuracy in children with BHFL. A between-participant experimental design was used to compare localization accuracy between children with BHFL and age-matched controls with normal hearing (NH). Eighteen children with BHFL who used CE and 18 age-matched NH controls. Children in both groups were divided into two age groups: older children (10-16 yr) and younger children (6-9 yr). All testing was done in a sound-treated booth with a horizontal array of 15 loudspeakers (radius of 1 m). The stimulus was a spondee word, "baseball": the level averaged 60 dB SPL and randomly roved (±8 dB). Each child was asked to identify the location of a sound source. Localization error was calculated across the loudspeaker array for each listening condition. A significant interaction was found between immediate benefit from OFD and duration of CE usage. Longer CE usage was associated with degraded localization accuracy using OFDs. Regardless of chronological age

[Constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss].

Science.gov (United States)

Li, Youjin; Yang, Jun; Li, Yun

2011-01-01

To analyze the constitute, imaging and auditory characteristics of pediatric patients with congenital malformations of inner ear in sensorineural hearing loss(SNHL). Imaging and auditory data of 125 cases (225 ears) in 860 pediatric patients with congenital SNHL who referred to ENT department of Shanghai Children Medical Center from February 2005 to January 2010 were retrospectively studied. Congenital malformations of inner ear accounted for 14.5% in 860 pediatric patients with congenital SNHL. Bilateral ear was involved in 98 cases (78.4%), unilateral in 27 cases (21.6%). One hundred and sixty-seven ears (74.2%) were identified as profound deafness, 36 ears (16%) severe deafness and 22 ears (9.8%) moderate deafness in 225 ears, respectively. In present group, large vestibular aqueduct (75.6%) was the most common and next was vestibular deformity (32%), then cochleovestibular deformity (23.1%). Mondini deformity (55.8%) was the most common and common cavity deformity (28.9%) next in cochleovestibular deformity. Profound deafness in cochlea involved congenital malformations of inner ear was significantly more than those in no cochlea involved malformations. The results are of importance for understanding the constitute of congenital malformations of inner ear in pediatric patients with congenital SNHL in China, for etiological diagnosis of congenital SNHL, for intervention including hearing aids or cochlear implant and prognosis.

Adaptive Changes in the Vestibular System of Land Snail to a 30-Day Spaceflight and Readaptation on Return to Earth

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Nikolay Aseyev

2017-11-01

Full Text Available The vestibular system receives a permanent influence from gravity and reflexively controls equilibrium. If we assume gravity has remained constant during the species' evolution, will its sensory system adapt to abrupt loss of that force? We address this question in the land snail Helix lucorum exposed to 30 days of near weightlessness aboard the Bion-M1 satellite, and studied geotactic behavior of postflight snails, differential gene expressions in statocyst transcriptome, and electrophysiological responses of mechanoreceptors to applied tilts. Each approach revealed plastic changes in the snail's vestibular system assumed in response to spaceflight. Absence of light during the mission also affected statocyst physiology, as revealed by comparison to dark-conditioned control groups. Readaptation to normal tilt responses occurred at ~20 h following return to Earth. Despite the permanence of gravity, the snail responded in a compensatory manner to its loss and readapted once gravity was restored.

Potencial evocado miogênico vestibular ocular: revisão de literatura

OpenAIRE

Silva,Tatiana Rocha; Resende,Luciana Macedo de; Santos,Marco Aurélio Rocha

2016-01-01

RESUMO Objetivo Identificar e sistematizar os principais estudos sobre o potencial evocado miogênico vestibular ocular e suas aplicações no diagnóstico das diversas doenças vestibulares. Estratégia de pesquisa Foram localizados artigos que descrevem a utilização do potencial evocado miogênico vestibular ocular na avaliação de doenças vestibulares nas bases PubMed, Web of Science, MEDLINE, Scopus, LILACS e SciELO. Critérios de seleção Foram incluídos estudos originais, com resumo disponí...

Early and phasic cortical metabolic changes in vestibular neuritis onset.

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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

Changes in resting-state fMRI in vestibular neuritis.

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Helmchen, Christoph; Ye, Zheng; Sprenger, Andreas; Münte, Thomas F

2014-11-01

Vestibular neuritis (VN) is a sudden peripheral unilateral vestibular failure with often persistent head movement-related dizziness and unsteadiness. Compensation of asymmetrical activity in the primary peripheral vestibular afferents is accomplished by restoration of impaired brainstem vestibulo-ocular and vestibulo-spinal reflexes, but presumably also by changing cortical vestibular tone imbalance subserving, e.g., spatial perception and orientation. The aim of this study was to elucidate (i) whether there are changes of cerebral resting-state networks with respect to functional interregional connectivity (resting-state activity) in VN patients and (ii) whether these are related to neurophysiological, perceptual and functional parameters of vestibular-induced disability. Using independent component analysis (ICA), we compared resting-state networks between 20 patients with unilateral VN and 20 age- and gender-matched healthy control subjects. Patients were examined in the acute VN stage and after 3 months. A neural network (component 50) comprising the parietal lobe, medial aspect of the superior parietal lobule, posterior cingulate cortex, middle frontal gyrus, middle temporal gyrus, parahippocampal gyrus, anterior cingulate cortex, insular cortex, caudate nucleus, thalamus and midbrain was modulated between acute VN patients and healthy controls and in patients over time. Within this network, acute VN patients showed decreased resting-state activity (ICA) in the contralateral intraparietal sulcus (IPS), in close vicinity to the supramarginal gyrus (SMG), which increased after 3 months. Resting-state activity in IPS tended to increase over 3 months in VN patients who improved with respect to functional parameters of vestibular-induced disability (VADL). Resting-state activity in the IPS was not related to perceptual (subjective visual vertical) or neurophysiological parameters of vestibular-induced disability (e.g., gain of vestibulo-ocular reflex, caloric

Conservative management of vestibular schwannoma--a prospective cohort study: treatment, symptoms, and quality of life.

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Breivik, Cathrine Nansdal; Varughese, Jobin K; Wentzel-Larsen, Tore; Vassbotn, Flemming; Lund-Johansen, Morten

2012-05-01

One hundred ninety-three patients with sporadic unilateral vestibular schwannoma given conservative management were enrolled in a prospective study. To evaluate the efficacy of conservative management and to determine the effect of an initial conservative management on the quality of life (QOL) and severity of audio vestibular symptoms. The patients underwent magnetic resonance imaging scans, clinical examination, and QOL assessment by 2 validated questionnaires, the Short Form-36 (SF-36) and Glasgow Benefit Inventory (GBI). Using regression analysis of clustered data, we analyzed possible associations between tumor growth and symptoms and tested whether our earlier finding that vertigo is associated with reduced QOL could be verified. The median follow-up time was 43 months (range, 9-115 months; SD, 21.48 months). Results are based on 703 clinical controls and 642 (SF-36) and 638 (GBI) questionnaires. Seven patients were lost to follow-up. Approximately 40% of patients were in need of treatment during follow-up. We found a statistically significant association between tinnitus and vertigo and tumor growth. Vertigo was found to significantly reduce QOL. There was a significant drop in the Social Function subscales of both SF-36 and GBI, possibly attributable to progressive hearing loss. Otherwise, there was no overall trend toward any change in QOL during the observation period. In addition, QOL seemed to be little affected by treatment. There was a small but statistically significant improvement in vestibular complaints and no change in the occurrence of tinnitus. Except for hearing loss caused by surgery, treatment did not affect symptoms or QOL significantly. Growth was associated with the occurrence of tinnitus and balance problems.

Gaze-Stabilizing Central Vestibular Neurons Project Asymmetrically to Extraocular Motoneuron Pools.

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Schoppik, David; Bianco, Isaac H; Prober, David A; Douglass, Adam D; Robson, Drew N; Li, Jennifer M B; Greenwood, Joel S F; Soucy, Edward; Engert, Florian; Schier, Alexander F

2017-11-22

Within reflex circuits, specific anatomical projections allow central neurons to relay sensations to effectors that generate movements. A major challenge is to relate anatomical features of central neural populations, such as asymmetric connectivity, to the computations the populations perform. To address this problem, we mapped the anatomy, modeled the function, and discovered a new behavioral role for a genetically defined population of central vestibular neurons in rhombomeres 5-7 of larval zebrafish. First, we found that neurons within this central population project preferentially to motoneurons that move the eyes downward. Concordantly, when the entire population of asymmetrically projecting neurons was stimulated collectively, only downward eye rotations were observed, demonstrating a functional correlate of the anatomical bias. When these neurons are ablated, fish failed to rotate their eyes following either nose-up or nose-down body tilts. This asymmetrically projecting central population thus participates in both upward and downward gaze stabilization. In addition to projecting to motoneurons, central vestibular neurons also receive direct sensory input from peripheral afferents. To infer whether asymmetric projections can facilitate sensory encoding or motor output, we modeled differentially projecting sets of central vestibular neurons. Whereas motor command strength was independent of projection allocation, asymmetric projections enabled more accurate representation of nose-up stimuli. The model shows how asymmetric connectivity could enhance the representation of imbalance during nose-up postures while preserving gaze stabilization performance. Finally, we found that central vestibular neurons were necessary for a vital behavior requiring maintenance of a nose-up posture: swim bladder inflation. These observations suggest that asymmetric connectivity in the vestibular system facilitates representation of ethologically relevant stimuli without

Extremely discrepant mutation spectrum of SLC26A4 between Chinese patients with isolated Mondini deformity and enlarged vestibular aqueduct.

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Huang, Shasha; Han, Dongyi; Yuan, Yongyi; Wang, Guojian; Kang, Dongyang; Zhang, Xin; Yan, Xiaofei; Meng, Xiaoxiao; Dong, Min; Dai, Pu

2011-09-30

Mutations in SLC26A4 cause Pendred syndrome (hearing loss with goiter) or DFNB4 (non-syndromic hearing loss with inner ear malformation, such as enlarged vestibular aqueduct or Mondini deformity). The relationship between mutations in SLC26A4 and Mondini deformity without enlarged vestibular aqueduct has not been studied in any Chinese deaf population. The purpose of this study was to assess whether mutations in the SLC26A4 gene cause Mondini deformity without an enlarged vestibular aqueduct (isolated Mondini deformity) in a Chinese population. In total, 144 patients with sensorineural hearing loss were included and subjected to high-resolution temporal bone CT. Among them, 28 patients with isolated Mondini dysplasia (MD group), 50 patients with enlarged vestibular aqueduct with Mondini dysplasia (EVA with MD group), 50 patients with enlarged vestibular aqueduct without Mondini dysplasia (EVA group), and 16 patients with other types of inner ear malformations (IEM group) were identified. The coding exons of SLC26A4 were analyzed in all subjects. DNA sequence analysis of SLC26A4 was performed in all 144 patients. In the different groups, the detection rate of the SLC26A4 mutation differed. In the isolated MD group, only one single allelic mutation in SLC26A4 was found in one patient (1/28, 3.6%). In the EVA with MD group, biallelic and monoallelic SLC26A4 mutations were identified in 46 patients (46/50, 92.0%) and three patients (3/50, 6.0%), respectively. Also, in the EVA group, biallelic and monoallelic SLC26A4 mutations were identified in 46 patients (46/50, 92.0%) and three patients (3/50, 6.0%), respectively. These percentages were identical to those in the EVA plus MD group. Only two patients carried monoallelic mutations of the SLC26A4 gene in the IEM group (2/16, 12.5%). There were significant differences in the frequency of SLC26A4 mutation among the groups (P0.5). Although mutations in the SLC26A4 gene were frequently found in Chinese EVA patients with and

The Vestibular Effects of Repeated Low-Level Blasts.

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Littlefield, Philip D; Pinto, Robin L; Burrows, Holly L; Brungart, Douglas S

2016-01-01

The objective of this study was to use a prospective cohort of United States Marine Corps (USMC) instructors to identify any acute or long-term vestibular dysfunction following repeated blast exposures during explosive breaching training. They were assessed in clinic and on location during training at the USMC Methods of Entry School, Quantico, VA. Subjects received comprehensive baseline vestibular assessments and these were repeated in order to identify longitudinal changes. They also received shorter assessments immediately following blast exposure in order to identify acute findings. The main outcome measures were the Neurobehavioral Symptom Inventory, vestibular Visual Analog Scale (VAS) of subjective vestibular function, videonystagmography (VNG), vestibular evoked myogenic potentials (VEMP), rotary chair (including the unilateral centrifugation test), computerized dynamic posturography, and computerized dynamic visual acuity. A total of 11 breachers and 4 engineers were followed for up to 17 months. No acute effects or longitudinal deteriorations were identified, but there were some interesting baseline group differences. Upbeat positional nystagmus was common, and correlated (p<0.005) with a history of mild traumatic brain injury (mTBI). Several instructors had abnormally short low-frequency phase leads on rotary chair testing. This study evaluated breaching instructors over a longer test period than any other study, and the results suggest that this population appears to be safe from a vestibular standpoint at the current exposure levels. Upbeat positional nystagmus correlated with a history of mTBI in this population, and this has not been described elsewhere. The data trends also suggest that this nystagmus could be an acute blast effect. However, the reasons for the abnormally short phase leads seen in rotary chair testing are unclear at this time. Further investigation seems warranted.

The frog vestibular system as a model for lesion-induced plasticity: basic neural principles and implications for posture control

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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

Central and peripheral components of short latency vestibular responses in the chicken

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Nazareth, A. M.; Jones, T. A.

1998-01-01

Far-field recordings of short latency vestibular responses to pulsed cranial translation are composed of a series of positive and negative peaks occurring within 10 ms following stimulus onset. In the bird, these vestibular evoked potentials (VsEPs) can be recorded noninvasively and have been shown in the chicken and quail to depend strictly upon the activation of the vestibular component of the eighth nerve. The utility of the VsEP in the study of vestibular systems is dependent upon a clear understanding of the neural sources of response components. The primary aim of the current research in the chicken was to critically test the hypotheses that 1) responses are generated by both peripheral and central neurons and 2) peaks P1 and N1 originate from first order vestibular neurons, whereas later waves primarily depend on activity in higher order neurons. The principal strategy used here was to surgically isolate the eighth nerve as it enters the brainstem. Interruption of primary afferents of the eighth nerve in the brainstem substantially reduced or eliminated peaks beyond P2, whereas P1 and N1 were generally spared. Surgical sections that spared vestibular pathways had little effect on responses. The degree of change in response components beyond N1 was correlated with the extent of damage to central vestibular relays. These findings support the conclusion that responses are produced by both peripheral and central elements of the vestibular system. Further, response peaks later than N1 appear to be dependent upon central relays, whereas P1 and N1 reflect activity of the peripheral nerve. These findings clarify the roles of peripheral and central neurons in the generation of vestibular evoked potentials and provide the basis for a more useful and detailed interpretation of data from vestibular response testing.

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

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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.

New insights into pathophysiology of vestibular migraine

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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

Assessment of auditory and vestibular functions in vitiligo patients

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Eman Abd Elmohsin Dawoud

2017-09-01

Conclusion: The results in this study showed that 50% of vitiligo patients suffered from peripheral vestibular disorders in addition to auditory affection. Vitiligo patients require routine monitoring for auditory and vestibular functions for early identification and monitoring of changes as the disease progress.

Translabyrinthine surgery for disabling vertigo in vestibular schwannoma patients

NARCIS (Netherlands)

Godefroy, W. P.; Hastan, D.; van der Mey, A. G. L.

2007-01-01

To determine the impact of translabyrinthine surgery on the quality of life in vestibular schwannoma patients with rotatory vertigo. Prospective study in 18 vestibular schwannoma patients. The study was conducted in a multispecialty tertiary care clinic. All 18 patients had a unilateral

Bilateral and unilateral ECT: effects on verbal and nonverbal memory.

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Squire, S R; Slater, P C

1978-11-01

The memory loss associated with bilateral and nondominant unilateral ECT was assessed with verbal memory tests known to be sensitive to left temporal lobe dysfunction and with nonverbal memory tests known to be sensitive to right temporal lobe dysfunction. Bilateral ECT markedly impaired delayed retention of verbal and nonverbal material. Right unilateral ECT impaired delayed retention of nonverbal material without measurably affecting retention of verbal material. Nonverbal memory was affected less by right unilateral ECT than by bilateral ECT. These findings, taken together with a consideration of the clinical efficacy of the two types of treatment, make what appears to be a conclusive case for unilateral over bilateral ECT.

Evidence of central and peripheral vestibular pathology in blast-related traumatic brain injury.

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Scherer, Matthew R; Burrows, Holly; Pinto, Robin; Littlefield, Philip; French, Louis M; Tarbett, Aaron K; Schubert, Michael C

2011-06-01

To prospectively assay the vestibular and oculomotor systems of blast-exposed service members with traumatic brain injury (TBI). Prospective, nonblinded, nonrandomized descriptive study. Tertiary care facility (Department of Defense Medical Center). Twenty-four service members recovering from blast-related TBI sustained in Iraq or Afghanistan. Focused history and physical, videonystagmography (VNG), rotational chair, cervical vestibular-evoked myogenic potentials, computerized dynamic posturography, and self-report measures. Vestibular testing confirms a greater incidence of vestibular and oculomotor dysfunction in symptomatic (vestibular-like dizziness) personnel with blast-related TBI relative to asymptomatic group members. VNG in the symptomatic group revealed abnormal nystagmus or oculomotor findings in 6 of 12 subjects tested. Similarly, rotational chair testing in this group revealed evidence of both peripheral (4/12) and central (2/12) vestibular pathology. By contrast, the asymptomatic group revealed less vestibular impairment with 1 of 10 rotational chair abnormalities. The asymptomatic group was further characterized by fewer aberrant nystagmus findings (4/12 abnormal VNGs). Computerized dynamic posturography testing revealed no significant differences between groups. Self-report measures demonstrated differences between groups. Vestibular function testing confirms a greater incidence of peripheral vestibular hypofunction in dizzy service members with blast-related TBI relative to those who are asymptomatic. Additionally, oculomotor abnormalities and/or nystagmus consistent with central involvement were present in 10 of the 24 study participants tested. The precise cause of these findings remains unknown.

Epidemiology of vestibular vertigo: a neurotologic survey of the general population.

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Neuhauser, H K; von Brevern, M; Radtke, A; Lezius, F; Feldmann, M; Ziese, T; Lempert, T

2005-09-27

The purpose of this study was to determine the prevalence and incidence of vestibular vertigo in the general population and to describe its clinical characteristics and associated factors. The neurotologic survey had a two-stage general population sampling design: nationwide modified random digit dialing sampling for participation in the German National Telephone Health Interview Survey 2003 (response rate 52%) with screening of a random sample of 4,869 participants for moderate or severe dizziness or vertigo, followed by detailed neurotologic interviews developed through piloting and validation (n = 1,003, response rate 87%). Diagnostic criteria for vestibular vertigo were rotational vertigo, positional vertigo, or recurrent dizziness with nausea and oscillopsia or imbalance. Vestibular vertigo was detected by our interview with a specificity of 94% and a sensitivity of 84[corrected]% in a concurrent validation study using neurotology clinic diagnoses as an accepted standard (n = 61). The lifetime prevalence of vestibular vertigo was 7.4[corrected]%, the 1-year prevalence was 4.9[corrected]%, and the incidence was 1.4[corrected]%. In 80% of affected individuals, vertigo resulted in a medical consultation, interruption of daily activities, or sick leave. Female sex, age, lower educational level, and various comorbid conditions, including tinnitus, depression, and several cardiovascular diseases and risk factors, were associated with vestibular vertigo in the past year in univariate analysis. In multivariable analysis, only female sex, self-reported depression, tinnitus, hypertension, and dyslipidemia had an independent effect on vestibular vertigo. Vestibular vertigo is common in the general population, affecting [corrected] 5% of adults in 1 year. The frequency and health care impact of vestibular symptoms at the population level have been underestimated.

Outcomes after vestibular rehabilitation and Wii® therapy in patients with chronic unilateral vestibular hypofunction.

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Verdecchia, Daniel H; Mendoza, Marcela; Sanguineti, Florencia; Binetti, Ana C

2014-01-01

Vestibular rehabilitation therapy is an exercise-based programme designed to promote central nervous system compensation for inner ear deficit. The objective of the present study was to analyse the differences in the perception of handicap, the risk of falls, and gaze stability in patients diagnosed with chronic unilateral vestibular hypofunction before and after vestibular rehabilitation treatment with complementary Wii® therapy. A review was performed on the clinical histories of patients in the vestibular rehabilitation area of a university hospital between April 2009 and May 2011. The variables studied were the Dizziness Handicap Inventory, the Dynamic Gait Index and dynamic visual acuity. All subjects received complementary Wii® therapy. There were 69 cases (41 woman and 28 men), with a median age of 64 years. The initial median Dizziness Handicap Inventory score was 40 points (range 0-84, percentile 25-75=20-59) and the final, 24 points (range 0-76, percentile 25-75=10.40), P<.0001. The initial median for the Dynamic Gait Index score was 21 points (range 8-24, percentile 25-75=17.5-2.3) and the final, 23 (range 12-24, percentile 25-75=21-23), P<.0001. The initial median for dynamic visual acuity was 2 (range 0-6, percentile 25-75=1-4) and the final, 1 (range 0-3, percentile 25-75=0-2), P<.0001. A reduction was observed in the Dizziness Handicap Inventory Values. Values for the Dynamic Gait Index increased and dynamic visual acuity improved. All these variations were statistically significant. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Bilateral nanophthalmos and pigmentary retinal dystrophy--an unusual syndrome.

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Proença, Helena; Castanheira-Dinis, A; Monteiro-Grillo, M

2006-09-01

To report the clinical picture of the rare association of nanophthalmos and pigmentary retinal dystrophy and its cataract surgery outcome. We report a case of a 60-year-old female who presented with bilateral slowly progressive visual loss. The patient presented with bilateral light perception visual acuity, exotropia, brunescent cataract hindering fundus examination and hypodontia. Ultrasonography revealed bilateral nanophthalmos. A visual-evoked potential was also performed preoperatively. Cataract surgery with +40D IOL implantation was uneventful. Postoperative fundus examination revealed pigmentary retinal dystrophy, confirmed by electrophysiologic tests. Glycosaminoglycan urinary excretion was normal. Congenital bilateral nanophthalmos may rarely be associated with pigmentary retinal dystrophy. We suggest thorough preoperative evaluation in nanophthalmic eyes for the exclusion of significant features concerning visual prognosis.

Hearing Loss due to Carbon Monoxide Poisoning

DEFF Research Database (Denmark)

Mehrparvar, Amir Houshang; Davari, Mohammad Hossein; Mollasadeghi, Abolfazl

2013-01-01

Carbon monoxide poisoning is one of the rare causes of hearing loss which may cause reversible or irreversible, unilateral or bilateral hearing loss after acute or chronic exposure. In this report, we present a case of bilateral sensorineural hearing loss in a secondary smelting workshop worker...... after an acute exposure to carbon monoxide. This complication was diagnosed by pure-tone audiometry and confirmed by transient evoked otoacoustic emissions. Hearing loss has not improved after 3 months of followup....

Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus : A Prospective Study

NARCIS (Netherlands)

van Zon, Alice; Smulders, Yvette E.; Ramakers, Geerte G. J.; Stegeman, Inge; Smit, Adriana L.; Van Zanten, Gijsbert A.; Stokroos, Robert J.; Hendrice, Nadia; Free, Rolien H.; Maat, Bert; Frijns, Johan H. M.; Mylanus, Emmanuel A. M.; Huinck, Wendy J.; Topsakal, Vedat; Tange, Rinze A.; Grolman, Wilko

Objectives/HypothesisTo determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation. Study DesignProspective study.

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...

Impaired mental rotation in benign paroxysmal positional vertigo and acute vestibular neuritis.

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Matteo eCandidi

2013-11-01

Full Text Available Vestibular processing is fundamental to our sense of orientation in space which is a core aspect of the representation of the self. Vestibular information is processed in a large subcortical-cortical neural network. Tasks requiring mental rotations of human bodies in space are known to activate neural regions within this network suggesting that vestibular processing is involved in the control of mental rotation. We studied whether mental rotation is impaired in patients suffering from two different forms of unilateral vestibular disorders (Vestibular Neuritis – VN- and Benign Paroxysmal positional Vertigo – BPPV with respect to healthy matched controls (C. We used two mental rotation tasks in which participants were required to: i mentally rotate their own body in space (egocentric rotation thus using vestibular processing to a large extent and ii mentally rotate human figures (allocentric rotation thus using own body representations to a smaller degree. Reaction times and accuracy of responses showed that VN and BPPV patients were impaired in both tasks with respect to C. Significantly, the pattern of results was similar in the three groups suggesting that patients were actually performing the mental rotation without using a different strategy from the control individuals. These results show that dysfunctional vestibular inflow impairs mental rotation of both own body and human figures suggesting that unilateral acute disorders of the peripheral vestibular input massively affect the cerebral processes underlying mental rotations.

INFLUENCE OF DANCE TRAINING ON SACCULOCOLLIC PATHWAY: VESTIBULAR EVOKED MYOGENIC POTENTIALS (VEMP) AS AN OBJECTIVE TOOL

OpenAIRE

Swathi; Sathish Kumar

2013-01-01

ABSTRACT : Auditory system is shaped by experience and training. Training (s ensory experience) induces neurophysiologic changes & plasticity in normal hearing individuals, hearing loss patients, hearing aid users and cochlear implanted subjects. Not only speech stimulus, but music also brings about functional and structural organi zation of the brain in musician compared to non - musicians. The Vestibular evoked myogenic potentials (VEMP) are a biphasic in...

Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

International Nuclear Information System (INIS)

Marcelli, Vincenzo; Esposito, Fabrizio; Aragri, Adriana; Furia, Teresa; Riccardi, Pasquale; Tosetti, Michela; Biagi, Laura; Marciano, Elio; Di Salle, Francesco

2009-01-01

Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

Effectiveness of Vestibular Rehabilitation Therapy for Treatment of Concussed Adolescents With Persistent Symptoms of Dizziness and Imbalance.

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Park, Kyoungyoun; Ksiazek, Thomas; Olson, Bernadette

2018-05-04

Adolescents who suffer sport concussion typically respond to a prescription of cognitive and physical rest in the acute phases of healing; however, some adolescents do not respond to rest alone. Dizziness, unsteadiness, and imbalance are impairments, which may linger longer than 30 days, leading to a diagnosis of postconcussion syndrome (PCS). Vestibular assessment and therapy may benefit adolescents suffering from these persistent symptoms. Does vestibular rehabilitation therapy (VRT) rather than continued prescription of rest (cognitive and physical) reduce recovery time and persistent symptoms of dizziness, unsteadiness, and imbalance in adolescents (12-18 y) who suffer PCS following a sports-related concussion? Summary of Key Findings: All 4 studies selected included adolescents suffering from PCS, specifically continued dizziness, unsteadiness, and imbalance. VRT was an effective intervention for this population. Adolescents presenting with this cluster of symptoms may also demonstrate verbal and visual memory loss linked to changes in the vestibular system postconcussion. Improved screening tools can help better understand vestibular system changes, identify adolescents who may benefit from VRT sooner, and decrease long-term impairments. Clinical Bottom Line: Moderate evidence supports that adolescents who suffer from persistent symptoms of dizziness, unsteadiness, and imbalance following sport concussion should be evaluated more specifically and earlier for vestibular dysfunction and can benefit from participation in individualized VRT. Early evaluation and treatment may result in a reduction of time lost from sport as well as a return to their premorbid condition. For these adolescents, VRT may be more beneficial than continued physical and cognitive rest when an adolescent's symptoms last longer than 30 days. Strength of Recommendation: Grade B evidence exists to support that VRT is more effective than continued cognitive and physical rest in reducing

Bilateral pulmonary infiltrates in association with disseminated actinomycosis.

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Dontfraid, F; Ramphal, R

1994-07-01

The most common infectious cause of bilateral upper-lobe pulmonary disease is tuberculosis. However, we recently encountered a patient with bilateral apical infiltrates and multiple soft-tissue abscesses caused by Actinomyces odontolyticus. Other findings included fever, weight loss, and leukocytosis, and the patient's only known source of immunosuppression was a long history of alcoholism. There was no history of diabetes, steroid use, or other chronic underlying disease. The diagnosis was made by culture of drainage fluid from one abscess. Therapy with intravenous penicillin G led to rapid clinical improvement and reduction in the infiltrates. To our knowledge, the presentation of pulmonary infection, with bilateral apical infiltrates due to A. odontolyticus has not been previously reported in the medical literature.

Postural Evaluation of Vertebral Column in Children and Teenagers with Hearing Loss

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Toscano, Carla Fabiana da Silva

2011-04-01

Full Text Available Introduction: Posture is determined by the performance of the visual, somatosensory and vestibular systems. Children with hearing loss can present problems in their posture or postural control, enabling postural deviations and alterations to appear in their vertebral column, possibly provoked by a hypoactivity of the vestibular system as a result of deafness. Objective: To evaluate the posture of the vertebral column in children and teenagers with hearing loss at school age, taking into consideration the sample gender and age. Method: A descriptive and prospective study was performed at both Duque de Caxias School and Rotary Rehabilitation and Special Education Center in Caruaru - Pernambuco. 44 students aged between 7-17 years old, out of whom 22 were female and 22 were male, with hearing loss were evaluated. The study was developed by way of a postural evaluation, using a symmetrograph, marking specific anatomical points with stickers placed over polystyrene balls and fixed with double-sided adhesive tape. Results:The results showed that all of the individuals evaluated in this study presented some kind of postural alteration in their vertebral column. Scoliosis was the most observed alteration among the students (84.1%, followed by thoracic hyperkyphosis (68.2%. Conclusion: It has been concluded that children and teenagers with hearing loss are exposed to postural alteration in their vertebral column. Such a condition can be associated with a number of factors comprising unfavorable ergonomics of the school environment, bad postural habits and impairment of the vestibular system by virtue of the hearing loss.

Prediction of Balance Compensation After Vestibular Schwannoma Surgery.

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Parietti-Winkler, Cécile; Lion, Alexis; Frère, Julien; Perrin, Philippe P; Beurton, Renaud; Gauchard, Gérome C

2016-06-01

Background Balance compensation after vestibular schwannoma (VS) surgery is under the influence of specific preoperative patient and tumor characteristics. Objective To prospectively identify potential prognostic factors for balance recovery, we compared the respective influence of these preoperative characteristics on balance compensation after VS surgery. Methods In 50 patients scheduled for VS surgical ablation, we measured postural control before surgery (BS), 8 (AS8) days after, and 90 (AS90) days after surgery. Based on factors found previously in the literature, we evaluated age, body mass index and preoperative physical activity (PA), tumor grade, vestibular status, and preference for visual cues to control balance as potential prognostic factors using stepwise multiple regression models. Results An asymmetric vestibular function was the sole significant explanatory factor for impaired balance performance BS, whereas the preoperative PA alone significantly contributed to higher performance at AS8. An evaluation of patients' balance recovery over time showed that PA and vestibular status were the 2 significant predictive factors for short-term postural compensation (BS to AS8), whereas none of these preoperative factors was significantly predictive for medium-term postoperative postural recovery (AS8 to AS90). Conclusions We identified specific preoperative patient and vestibular function characteristics that may predict postoperative balance recovery after VS surgery. Better preoperative characterization of these factors in each patient could inform more personalized presurgical and postsurgical management, leading to a better, more rapid balance recovery, earlier return to normal daily activities and work, improved quality of life, and reduced medical and societal costs. © The Author(s) 2015.

LA FUNCIÓN VESTIBULAR Y SU CONCORDANCIA FRENOLÓGICA: CONECTANDO LA HISTORIA DE LA FUNCIÓN CEREBRAL VESTIBULAR

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Jorge Eduardo Duque Parra

2012-09-01

Full Text Available En el presente trabajo se inter-relacionan eventos históricos y contemporáneos, que han permitido desde la intuición de los primeros frenólogos y posteriormente con aspectos clínicos y experimentales, determinar un acercamiento a la localización funcional cerebral del procesamiento de información vestibular, asociada con los movimientos de la cabeza. El objetivo es aclarar si se puede establecer un vínculo entre la información frenológica del siglo XVIII con el procesamiento funcional cortical vestibular, con base en investigaciones contemporáneas. Metodológicamente se compara la información vestibular que surgió de la frenología, con los datos contemporáneos de funcionales cerebrales. Se encontró que el sentido de la orientación espacial se postuló en la región craneal parietal de forma intuitiva por los pioneros de la Frenología, en coincidencia con el sabido procesamiento cerebral parietal para la aceleración angular y linear del movimiento de la cabeza. Se concluye que la asignación de la región frenológica 12 en la zona parietal craneal, es concordante, si se extrapola al lobo parietal, para el sentido del lugar y el sentido espacial, pues varios trabajos indican la asignación como zona cortical vestibular principal, a la que se encuentra en dicha región cerebral.

Quantification of vestibular-induced eye movements in zebrafish larvae

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Mo Weike

2010-09-01

Full Text Available Abstract Background Vestibular reflexes coordinate movements or sensory input with changes in body or head position. Vestibular-evoked responses that involve the extraocular muscles include the vestibulo-ocular reflex (VOR, a compensatory eye movement to stabilize retinal images. Although an angular VOR attributable to semicircular canal stimulation was reported to be absent in free-swimming zebrafish larvae, recent studies reveal that vestibular-induced eye movements can be evoked in zebrafish larvae by both static tilts and dynamic rotations that tilt the head with respect to gravity. Results We have determined herein the basis of sensitivity of the larval eye movements with respect to vestibular stimulus, developmental stage, and sensory receptors of the inner ear. For our experiments, video recordings of larvae rotated sinusoidally at 0.25 Hz were analyzed to quantitate eye movements under infrared illumination. We observed a robust response that appeared as early as 72 hours post fertilization (hpf, which increased in amplitude over time. Unlike rotation about an earth horizontal axis, rotation about an earth vertical axis at 0.25 Hz did not evoke eye movements. Moreover, vestibular-induced responses were absent in mutant cdh23 larvae and larvae lacking anterior otoliths. Conclusions Our results provide evidence for a functional vestibulo-oculomotor circuit in 72 hpf zebrafish larvae that relies upon sensory input from anterior/utricular otolith organs.

Bilateral vision loss due to Leber's hereditary optic neuropathy after long-term alcohol, nicotine and drug abuse.

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Maass, Johanna; Matthé, Egbert

2018-04-01

Leber's hereditary optic neuropathy is relatively rare, and no clinical pathognomonic signs exist. We present a rare case of bilateral vision loss of a patient with multiple drug abuse in the history. A 31-year-old man presented with a history of progressive, decreased vision in both eyes for 6 month. On examination, his visual acuity was hand motion in both eyes. Funduscopy demonstrated a temporal pallor of the optic disc. Goldmann visual field perimetry showed a crescent visual field in the right eye and a circular decrease to less than 50 ° in the left eye. Electroretinogram showed a scotopic b-wave amplitude reduction. Optical coherence tomographies, Heidelberg Retina tomography, visual evoked potentials, and magnetic resonance imaging with contrast as well as blood tests were normal. The patient reported to consume various kinds of drugs as well as recreational drug use and alcohol consumption since he was 16 years old. We started a hemodilution therapy, believing the patient suffered from a bilateral, toxic optic neuropathy due to his lifestyle. Laboratory results later on showed Leber's hereditary optic neuropathy. Leber's hereditary optic neuropathy is a rare disease without a typical, pathognomonic presentation. Even though the patient gave good reasons for a toxic optic neuropathy, one should never stop to test for other diseases.

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.

Bilateral Ramsay Hunt syndrome in a diabetic patient

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Goyal Amit

2004-12-01

Full Text Available Abstract Background Herpes zoster oticus accounts for about 10% cases of facial palsy, which is usually unilateral and complete and full recovery occurs in only about 20% of untreated patients. Bilateral herpes zoster oticus can sometime occur in immunocompromised patients, though incidence is very rare. Case presentation Diabetic male, 57 year old presented to us with bilateral facial palsy due to herpes zoster oticus. Patient was having bilateral mild to moderate sensorineural hearing loss. Patient was treated with appropriate metabolic control, anti-inflammatory drugs and intravenous acyclovir. Due to uncontrolled diabetes, glucocorticoids were not used in this patient. Significant improvement in hearing status and facial nerve functions were seen in this patient. Conclusions Herpes zoster causes severe infections in diabetic patients and can be a cause of bilateral facial palsy and bilateral Ramsay Hunt syndrome. Herpes zoster in diabetic patients should be treated with appropriate metabolic control, NSAIDS and intravenous acyclovir, which we feel should be started at the earliest. Glucocorticoids should be avoided in diabetic patients.

Vestibular asymmetry predicts falls among elderly patients with multi- sensory dizziness

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Ekvall Hansson, Eva; Magnusson, M?ns

2013-01-01

Background: Dizziness is the most common symptom in elderly patients and has been identified as a risk factor for falls. While BPPV is the most common cause of dizziness among elderly, multisensory deficits is the second, with visual, vestibular and proprioceptive reduced function. Asymmetric vestibular function is overrepresented in elderly persons with hip fractures and wrist fractures and can be accessed for screening. The objective was to study if vestibular asymmetry, vibration sense, ba...

Bilateral uveitis and Usher syndrome: a case report.

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Benson, Matthew D; MacDonald, Ian M

2015-03-15

Usher syndrome is a genetically heterogeneous condition and represents the most common cause of inherited combined vision and hearing loss. Deficits manifest as sensorineural hearing loss that typically develops at a young age and retinitis pigmentosa that can lead to peripheral vision loss and night blindness. As a result, this syndrome can have a significant impact on a patient's quality of life. Previous studies have described an association between Usher syndrome and Fuchs' heterochromic iridocyclitis, a form of non-granulomatous uveitis that generally presents in a unilateral manner. We present a rare finding of bilateral uveitis and, to the best of our knowledge, the first report of granulomatous uveitis as a feature in a patient with Usher syndrome. A 45-year-old Caucasian woman with a known history of retinitis pigmentosa presented to our clinic with suspected Usher syndrome, given her report of long-standing hearing loss. Aside from a mild loss in visual acuity, our patient was otherwise asymptomatic. Visual field testing, audiology and electroretinography findings supported the diagnosis of Usher syndrome. With slit lamp examination she was found to have bilateral keratic precipitates, with large, greasy-white, mutton-fat keratic precipitates on the endothelial surface of her left eye. A thorough work-up that included blood tests and imaging was negative for an alternative cause of her uveitis. We present a rare finding of bilateral uveitis and what we believe to be the first reported instance of mutton-fat keratic precipitates and granulomatous uveitis as a feature in a patient with Usher syndrome. By identifying atypical presentations of the disease, we hope to contribute to the range of ophthalmic conditions that may be seen in association with Usher syndrome.

Age-related decline in functional connectivity of the vestibular cortical network.

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Cyran, Carolin Anna Maria; Boegle, Rainer; Stephan, Thomas; Dieterich, Marianne; Glasauer, Stefan

2016-04-01

In the elderly, major complaints include dizziness and an increasing number of falls, possibly related to an altered processing of vestibular sensory input. In this study, we therefore investigate age-related changes induced by processing of vestibular sensory stimulation. While previous functional imaging studies of healthy aging have investigated brain function during task performance or at rest, we used galvanic vestibular stimulation during functional MRI in a task-free sensory stimulation paradigm to study the effect of healthy aging on central vestibular processing, which might only become apparent during stimulation processing. Since aging may affect signatures of brain function beyond the BOLD-signal amplitude-such as functional connectivity or temporal signal variability--we employed independent component analysis and partial least squares analysis of temporal signal variability. We tested for age-associated changes unrelated to vestibular processing, using a motor paradigm, voxel-based morphometry and diffusion tensor imaging. This allows us to control for general age-related modifications, possibly originating from vascular, atrophic or structural connectivity changes. Age-correlated decreases of functional connectivity and increases of BOLD--signal variability were associated with multisensory vestibular networks. In contrast, no age-related functional connectivity changes were detected in somatosensory networks or during the motor paradigm. The functional connectivity decrease was not due to structural changes but to a decrease in response amplitude. In synopsis, our data suggest that both the age-dependent functional connectivity decrease and the variability increase may be due to deteriorating reciprocal cortico-cortical inhibition with age and related to multimodal vestibular integration of sensory inputs.

Anton's Syndrome due to Bilateral Ischemic Occipital Lobe Strokes.

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Zukić, Sanela; Sinanović, Osman; Zonić, Lejla; Hodžić, Renata; Mujagić, Svjetlana; Smajlović, Edina

2014-01-01

We present a case of a patient with Anton's syndrome (i.e., visual anosognosia with confabulations), who developed bilateral occipital lobe infarct. Bilateral occipital brain damage results in blindness, and patients start to confabulate to fill in the missing sensory input. In addition, the patient occasionally becomes agitated and talks to himself, which indicates that, besides Anton's syndrome, he might have had Charles Bonnet syndrome, characterized by both visual loss and hallucinations. Anton syndrome, is not so frequent condition and is most commonly caused by ischemic stroke. In this particular case, the patient had successive bilateral occipital ischemia as a result of massive stenoses of head and neck arteries.

Left hemispheric dominance of vestibular processing indicates lateralization of cortical functions in rats.

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Best, Christoph; Lange, Elena; Buchholz, Hans-Georg; Schreckenberger, Mathias; Reuss, Stefan; Dieterich, Marianne

2014-11-01

Lateralization of cortical functions such as speech dominance, handedness and processing of vestibular information are present not only in humans but also in ontogenetic older species, e.g. rats. In human functional imaging studies, the processing of vestibular information was found to be correlated with the hemispherical dominance as determined by the handedness. It is located mainly within the right hemisphere in right handers and within the left hemisphere in left handers. Since dominance of vestibular processing is unknown in animals, our aim was to study the lateralization of cortical processing in a functional imaging study applying small-animal positron emission tomography (microPET) and galvanic vestibular stimulation in an in vivo rat model. The cortical and subcortical network processing vestibular information could be demonstrated and correlated with data from other animal studies. By calculating a lateralization index as well as flipped region of interest analyses, we found that the vestibular processing in rats follows a strong left hemispheric dominance independent from the "handedness" of the animals. These findings support the idea of an early hemispheric specialization of vestibular cortical functions in ontogenetic older species.

Impact of Diabetic Complications on Balance and Falls: Contribution of the Vestibular System.

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D'Silva, Linda J; Lin, James; Staecker, Hinrich; Whitney, Susan L; Kluding, Patricia M

2016-03-01

Diabetes causes many complications, including retinopathy and peripheral neuropathy, which are well understood as contributing to gait instability and falls. A less understood complication of diabetes is the effect on the vestibular system. The vestibular system contributes significantly to balance in static and dynamic conditions by providing spatially orienting information. It is noteworthy that diabetes has been reported to affect vestibular function in both animal and clinical studies. Pathophysiological changes in peripheral and central vestibular structures due to diabetes have been noted. Vestibular dysfunction is associated with impaired balance and a higher risk of falls. As the prevalence of diabetes increases, so does the potential for falls due to diabetic complications. The purpose of this perspective article is to present evidence on the pathophysiology of diabetes-related complications and their influence on balance and falls, with specific attention to emerging evidence of vestibular dysfunction due to diabetes. Understanding this relationship may be useful for screening (by physical therapists) for possible vestibular dysfunction in people with diabetes and for further developing and testing the efficacy of interventions to reduce falls in this population. © 2016 American Physical Therapy Association.

Integration of Visual and Vestibular Information Used to Discriminate Rotational Self-Motion

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Florian Soyka

2011-10-01

Full Text Available Do humans integrate visual and vestibular information in a statistically optimal fashion when discriminating rotational self-motion stimuli? Recent studies are inconclusive as to whether such integration occurs when discriminating heading direction. In the present study eight participants were consecutively rotated twice (2s sinusoidal acceleration on a chair about an earth-vertical axis in vestibular-only, visual-only and visual-vestibular trials. The visual stimulus was a video of a moving stripe pattern, synchronized with the inertial motion. Peak acceleration of the reference stimulus was varied and participants reported which rotation was perceived as faster. Just-noticeable differences (JND were estimated by fitting psychometric functions. The visual-vestibular JND measurements are too high compared to the predictions based on the unimodal JND estimates and there is no JND reduction between visual-vestibular and visual-alone estimates. These findings may be explained by visual capture. Alternatively, the visual precision may not be equal between visual-vestibular and visual-alone conditions, since it has been shown that visual motion sensitivity is reduced during inertial self-motion. Therefore, measuring visual-alone JNDs with an underlying uncorrelated inertial motion might yield higher visual-alone JNDs compared to the stationary measurement. Theoretical calculations show that higher visual-alone JNDs would result in predictions consistent with the JND measurements for the visual-vestibular condition.

Potenciais miogênicos evocados vestibulares: metodologias de registro em homens e cobaias Vestibular evoked myogenic potential: recording methods in humans and guinea pigs

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Aline Cabral de Oliveira

2008-10-01

Full Text Available O potencial miogênico evocado vestibular (VEMP é um teste clínico que avalia a função vestibular através de um reflexo vestíbulo-cervical inibitório captado nos músculos do corpo em resposta à estimulação acústica de alta intensidade. OBJETIVO: Verificar e analisar os diversos métodos de registro dos potenciais miogênicos evocados vestibulares no homem e em cobaias. MATERIAL E MÉTODO: Realizou-se busca eletrônica nas bases de dados MEDLINE, LILACS, SCIELO e COCHRANE. RESULTADOS: Foram verificadas divergências quanto às formas de registro dos potenciais miogênicos evocados vestibulares, relacionadas com os seguintes fatores: posição do paciente no momento do registro, tipo de estímulo sonoro utilizado (clicks ou tone bursts, parâmetros para a promediação dos estímulos (intensidade, freqüência, tempo de apresentação, filtros, ganho de amplificação das respostas e janelas para captação dos estímulos, tipo de fone utilizado e forma de apresentação dos estímulos (monoaural ou binaural, ipsi ou contralateral. CONCLUSÃO: Não existe consenso na literatura quanto ao melhor método de registro dos potenciais evocados miogênicos vestibulares, havendo necessidade de pesquisas mais específicas para comparação entre estes registros e a definição de um modelo padrão para a utilização na prática clínica.The vestibular evoked myogenic potential (VEMP is a clinical test that assess the vestibular function by means of an inhibitory vestibulo-neck reflex, recorded in body muscles in response to high intensity acoustic stimuli. AIM: To check and analyze the different methods used to record VEMPs in humans and in guinea pigs. MATERIALS AND METHODS: We researched the following databases: MEDLINE, LILACS, SCIELO and COCHRANE. RESULTS: we noticed discrepancies in relation to the ways used to record the vestibular evoked myogenic potentials in relation to the following factors: patient position at the time of recording

Post-operative complications after removal of sporadic vestibular schwannoma via retrosigmoid-suboccipital approach: current diagnosis and management.

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Charalampakis, Stylianos; Koutsimpelas, Dimitrios; Gouveris, Haralampos; Mann, Wolf

2011-05-01

The retrosigmoid (suboccipital) approach is one of four surgical approaches for the treatment of vestibular schwannomas (acoustic neuromas). It is increasingly used by otologic surgeons, and in experienced hands is associated with improved results and more limited complications. Mortality rates are minimal and often zero, while postoperative sequelae, on the other hand, are not rare. In order to not only save the patient's life, but also to assure good quality of life after the surgery, one must consider many different aspects of management of the respective complications. In this review the issues of current management of CSF leak and meningitis, facial paresis, headache, hearing loss, unsteadiness, disequilibrium, vertigo, tinnitus, cerebellar and brain stem injuries or abscess, vascular complications and venous air embolism after retrosigmoid approach for removal of vestibular schwannomas are presented. © Springer-Verlag 2011

Otological and vestibular symptoms in patients with low grade (Quebec grades one and two) whiplash injury.

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Rowlands, R G; Campbell, I K; Kenyon, G S

2009-02-01

To establish the prevalence of new vestibular and otological symptoms in a group of patients who had sustained a low grade (Quebec grades one or two) whiplash injury. A retrospective review of the case records of 109 patients undergoing assessment by a single practitioner for the purposes of compiling a medicolegal report on their whiplash injury. Four patients complained of short-lived, non-specific dizziness symptoms in the acute phase following their original injury. There were no reports of vertigo, tinnitus or hearing loss after a mean period of 149 days following the whiplash injury. No patients reported otological or persistent vestibular symptoms in the acute phase following their whiplash injury. This suggests that caution should be exercised when attributing these symptoms to such an injury. Before whiplash injuries are admitted as an aetiological factor in the development of such symptoms, other causes should be excluded.

Congenital sensorineural hearing loss

International Nuclear Information System (INIS)

Mafee, M.F.; Selis, J.E.; Yannias, D.A.; Valvassori, G.E.; Pruzansky, S.; Applebaum, E.L.; Capek, V.

1984-01-01

The ears of 47 selected patients with congenital sensorineural hearing loss were examined with complex-motion tomography. The patients were divided into 3 general categories: those with a recognized syndrome, those with sensorineural hearing loss unrelated to any known syndrome, and those with microtia. A great variety of inner ear anomalies was detected, but rarely were these characteristic of a particular clinical entity. The most common finding was the Mondini malformation or one of its variants. Isolated dysplasia of the internal auditory canal or the vestibular aqueduct may be responsible for sensorineural hearing loss in some patients. Patients with microtia may also have severe inner ear abnormalities despite the fact that the outer and inner ears develop embryologically from completely separate systems

Congenital sensorineural hearing loss

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Mafee, M.F.; Selis, J.E.; Yannias, D.A.; Valvassori, G.E.; Pruzansky, S.; Applebaum, E.L.; Capek, V.

1984-02-01

The ears of 47 selected patients with congenital sensorineural hearing loss were examined with complex-motion tomography. The patients were divided into 3 general categories: those with a recognized syndrome, those with sensorineural hearing loss unrelated to any known syndrome, and those with microtia. A great variety of inner ear anomalies was detected, but rarely were these characteristic of a particular clinical entity. The most common finding was the Mondini malformation or one of its variants. Isolated dysplasia of the internal auditory canal or the vestibular aqueduct may be responsible for sensorineural hearing loss in some patients. Patients with microtia may also have severe inner ear abnormalities despite the fact that the outer and inner ears develop embryologically from completely separate systems.

Functional balance associated factors in the elderly with chronic vestibular disorder.

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Gazzola, Juliana Maria; Perracini, Monica Rodrigues; Ganança, Maurício Malavasi; Ganança, Fernando Freitas

2006-01-01

Daily activities can be challenging for the elderly. 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. 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 ([FORMULA: SEE TEXT]). Statistically significant associations and correlations were observed between total BBS score and age ([FORMULA: SEE TEXT]=-0.354; pfalls (p=0.010), tendency to fall (p=0.002), topographic diagnosis of central vestibular disorder (pFunctional 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 illnesses, use of multiple medications, recurrent falls, tendency to fall, central vestibular syndromes, daily dizziness, mobility and gait impairments.

Kv1 channels and neural processing in vestibular calyx afferents

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Frances L Meredith

2015-06-01

Full Text Available Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K+ channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K+ channels could help alleviate vestibular dysfunction on earth and in space.

Kv1 channels and neural processing in vestibular calyx afferents.

Science.gov (United States)

Meredith, Frances L; Kirk, Matthew E; Rennie, Katherine J

2015-01-01

Potassium-selective ion channels are important for accurate transmission of signals from auditory and vestibular sensory end organs to their targets in the central nervous system. During different gravity conditions, astronauts experience altered input signals from the peripheral vestibular system resulting in sensorimotor dysfunction. Adaptation to altered sensory input occurs, but it is not explicitly known whether this involves synaptic modifications within the vestibular epithelia. Future investigations of such potential plasticity require a better understanding of the electrophysiological mechanisms underlying the known heterogeneity of afferent discharge under normal conditions. This study advances this understanding by examining the role of the Kv1 potassium channel family in mediating action potentials in specialized vestibular afferent calyx endings in the gerbil crista and utricle. Pharmacological agents selective for different sub-types of Kv1 channels were tested on membrane responses in whole cell recordings in the crista. Kv1 channels sensitive to α-dendrotoxin and dendrotoxin-K were found to prevail in the central regions, whereas K(+) channels sensitive to margatoxin, which blocks Kv1.3 and 1.6 channels, were more prominent in peripheral regions. Margatoxin-sensitive currents showed voltage-dependent inactivation. Dendrotoxin-sensitive currents showed no inactivation and dampened excitability in calyces in central neuroepithelial regions. The differential distribution of Kv1 potassium channels in vestibular afferents supports their importance in accurately relaying gravitational and head movement signals through specialized lines to the central nervous system. Pharmacological modulation of specific groups of K(+) channels could help alleviate vestibular dysfunction on earth and in space.

Diagnostic criteria for enlarged vestibular aqueduct (EVA) on CT of the temporal bones. Borderline cases of EVA

International Nuclear Information System (INIS)

Matsumoto, Mariko; Hoshino, Tomoyuki; Kikura, Mikino; Kikawada, Keiko; Kikawada, Toru

2005-01-01

The objective of this study was to examine measurements of the vestibular aqueduct on axial CT figures and to examine the cases with borderline EVA. The width of the vestibular aqueduct was measured in two places, the midpoint of the duct and the external aperture in the posterior cranial fossa. Criteria was as follow: Enlargement; ≥1.5 mm at the midpoint, ≥2 mm at the aperture, Borderline; 1-1.4 mm at the midpoint, 1.5-1.9 mm at the aperture. Three hundred forty-five cases with CT scans of the temporal bones taken during July 2003 to June 2004 in the secondary ENT referral center. Those patients include sensorinearal, mixed or conductive deafness, vertigo, ear infections and other ear diseases. Enlarged vestibular aqueduct was found in 10 ears with sensorineural deafness (SD) and 2 ears without SD. Borderline measurements were found in 19 ears with SD and 33 ears without SD. The enlarged midpoint measurement was not seen in the cases without SD. More than 1.5 mm of the definition for the enlargement at the midpoint of the vestibular aqueduct seemed to be appropriate in the clinical situation. The measurement at the midpoint of the duct is more reliable than at the external aperture. The conductive component in EVA Syndrome with mixed hearing loss is present only at the lower frequencies (250, 500 Hz), not at the middle and higer frequencies. Long-term follow-up of hearing should be done in the borderline cases with check-up of PDS gene anomaly if necessary. (author)

Pre-adaptation to noisy Galvanic vestibular stimulation is associated with enhanced sensorimotor performance in novel vestibular environments

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Steven T Moore

2015-06-01

Full Text Available Performance on a visuomotor task in the presence of novel vestibular stimulation was assessed in nine healthy subjects. Four subjects had previously been adapted to 120 minutes exposure to noisy Galvanic vestibular stimulation (GVS over 12 weekly sessions of 10 minutes; the remaining five subjects had never experienced GVS. Subjects were seated in a flight simulator and asked to null the roll motion of a visual bar presented on a screen using a joystick. Both the visual bar and the simulator cabin were moving in roll with a pseudorandom (sum of sines waveform that were uncorrelated. The cross correlation coefficient, which ranges from 1 (identical waveforms to 0 (unrelated waveforms, was calculated for the ideal (perfect nulling of bar motion and actual joystick input waveform for each subject. The cross correlation coefficient for the GVS-adapted group (0.90 [SD 0.04] was significantly higher (t[8]=3.162; p=0.013 than the control group (0.82 [SD 0.04], suggesting that prior adaptation to GVS was associated with an enhanced ability to perform the visuomotor task in the presence of novel vestibular noise.

Vestibular-somatosensory interactions: effects of passive whole-body rotation on somatosensory detection.

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Elisa Raffaella Ferrè

Full Text Available Vestibular signals are strongly integrated with information from several other sensory modalities. For example, vestibular stimulation was reported to improve tactile detection. However, this improvement could reflect either a multimodal interaction or an indirect interaction driven by vestibular effects on spatial attention and orienting. Here we investigate whether natural vestibular activation induced by passive whole-body rotation influences tactile detection. In particular, we assessed the ability to detect faint tactile stimuli to the fingertips of the left and right hand during spatially congruent or incongruent rotations. We found that passive whole-body rotations significantly enhanced sensitivity to faint shocks, without affecting response bias. Critically, this enhancement of somatosensory sensitivity did not depend on the spatial congruency between the direction of rotation and the hand stimulated. Thus, our results support a multimodal interaction, likely in brain areas receiving both vestibular and somatosensory signals.

Migraine patients consistently show abnormal vestibular bedside tests.

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Maranhão, Eliana Teixeira; Maranhão-Filho, Péricles; Luiz, Ronir Raggio; Vincent, Maurice Borges

2016-01-01

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. 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. Cross-sectional study including sixty individuals - thirty migraineurs, 25 women, 19-60 y-o; and 30 gender/age healthy paired controls. 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). Migraine patients consistently showed abnormal vestibular bedside tests when compared with controls.

Home-Based Computer Gaming in Vestibular Rehabilitation of Gaze and Balance Impairment.

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Szturm, Tony; Reimer, Karen M; Hochman, Jordan

2015-06-01

Disease or damage of the vestibular sense organs cause a range of distressing symptoms and functional problems that could include loss of balance, gaze instability, disorientation, and dizziness. A novel computer-based rehabilitation system with therapeutic gaming application has been developed. This method allows different gaze and head movement exercises to be coupled to a wide range of inexpensive, commercial computer games. It can be used in standing, and thus graded balance demands using a sponge pad can be incorporated into the program. A case series pre- and postintervention study was conducted of nine adults diagnosed with peripheral vestibular dysfunction who received a 12-week home rehabilitation program. The feasibility and usability of the home computer-based therapeutic program were established. Study findings revealed that using head rotation to interact with computer games, when coupled to demanding balance conditions, resulted in significant improvements in standing balance, dynamic visual acuity, gaze control, and walking performance. Perception of dizziness as measured by the Dizziness Handicap Inventory also decreased significantly. These preliminary findings provide support that a low-cost home game-based exercise program is well suited to train standing balance and gaze control (with active and passive head motion).

How does high-frequency sound or vibration activate vestibular receptors?

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Curthoys, I S; Grant, J W

2015-03-01

The mechanism by which vestibular neural phase locking occurs and how it relates to classical otolith mechanics is unclear. Here, we put forward the hypothesis that sound and vibration both cause fluid pressure waves in the inner ear and that it is these pressure waves which displace the hair bundles on vestibular receptor hair cells and result in activation of type I receptor hair cells and phase locking of the action potentials in the irregular vestibular afferents, which synapse on type I receptors. This idea has been suggested since the early neural recordings and recent results give it greater credibility.

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.

Vision and Vestibular System Dysfunction Predicts Prolonged Concussion Recovery in Children.

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Master, Christina L; Master, Stephen R; Wiebe, Douglas J; Storey, Eileen P; Lockyer, Julia E; Podolak, Olivia E; Grady, Matthew F

2018-03-01

Up to one-third of children with concussion have prolonged symptoms lasting beyond 4 weeks. Vision and vestibular dysfunction is common after concussion. It is unknown whether such dysfunction predicts prolonged recovery. We sought to determine which vision or vestibular problems predict prolonged recovery in children. A retrospective cohort of pediatric patients with concussion. A subspecialty pediatric concussion program. Four hundred thirty-two patient records were abstracted. Presence of vision or vestibular dysfunction upon presentation to the subspecialty concussion program. The main outcome of interest was time to clinical recovery, defined by discharge from clinical follow-up, including resolution of acute symptoms, resumption of normal physical and cognitive activity, and normalization of physical examination findings to functional levels. Study subjects were 5 to 18 years (median = 14). A total of 378 of 432 subjects (88%) presented with vision or vestibular problems. A history of motion sickness was associated with vestibular dysfunction. Younger age, public insurance, and presence of headache were associated with later presentation for subspecialty concussion care. Vision and vestibular problems were associated within distinct clusters. Provocable symptoms with vestibulo-ocular reflex (VOR) and smooth pursuits and abnormal balance and accommodative amplitude (AA) predicted prolonged recovery time. Vision and vestibular problems predict prolonged concussion recovery in children. A history of motion sickness may be an important premorbid factor. Public insurance status may represent problems with disparities in access to concussion care. Vision assessments in concussion must include smooth pursuits, saccades, near point of convergence (NPC), and accommodative amplitude (AA). A comprehensive, multidomain assessment is essential to predict prolonged recovery time and enable active intervention with specific school accommodations and targeted rehabilitation.

Diabetes, vestibular dysfunction, and falls: analyses from the National Health and Nutrition Examination Survey.

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Agrawal, Yuri; Carey, John P; Della Santina, Charles C; Schubert, Michael C; Minor, Lloyd B

2010-12-01

Patients with diabetes are at increased risk both for falls and for vestibular dysfunction, a known risk factor for falls. Our aims were 1) to further characterize the vestibular dysfunction present in patients with diabetes and 2) to evaluate for an independent effect of vestibular dysfunction on fall risk among patients with diabetes. National cross-sectional survey. Ambulatory examination centers. Adults from the United States aged 40 years and older who participated in the 2001-2004 National Health and Nutrition Examination Survey (n = 5,86). Diagnosis of diabetes, peripheral neuropathy, and retinopathy. Vestibular function measured by the modified Romberg Test of Standing Balance on Firm and Compliant Support Surfaces and history of falling in the previous 12 months. We observed a higher prevalence of vestibular dysfunction in patients with diabetes with longer duration of disease, greater serum hemoglobin A1c levels and other diabetes-related complications, suggestive of a dose-response relationship between diabetes mellitus severity and vestibular dysfunction. We also noted that vestibular dysfunction independently increased the odds of falling more than 2-fold among patients with diabetes (odds ratio, 2.3; 95% confidence interval, 1.1-5.1), even after adjusting for peripheral neuropathy and retinopathy. Moreover, we found that including vestibular dysfunction, peripheral neuropathy, and retinopathy in multivariate models eliminated the significant association between diabetes and fall risk. Vestibular dysfunction may represent a newly recognized diabetes-related complication, which acts as a mediator of the effect of diabetes mellitus on fall risk.

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

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Grassi, S; Pettorossi, V E

2001-08-01

The analysis of cellular-molecular events mediating synaptic plasticity within vestibular nuclei is an attempt to explain the mechanisms underlying vestibular plasticity phenomena. The present review is meant to illustrate the main results, obtained in vitro, on the mechanisms underlying long-term changes in synaptic strength within the medial vestibular nuclei. The synaptic plasticity phenomena taking place at the level of vestibular nuclei could be useful for adapting and consolidating the efficacy of vestibular neuron responsiveness to environmental requirements, as during visuo-vestibular recalibration and vestibular compensation. Following a general introduction on the most salient features of vestibular compensation and visuo-vestibular adaptation, which are two plastic events involving neuronal circuitry within the medial vestibular nuclei, the second and third sections describe the results from rat brainstem slice studies, demonstrating the possibility to induce long-term potentiation and depression in the medial vestibular nuclei, following high frequency stimulation of the primary vestibular afferents. In particular the mechanisms sustaining the induction and expression of vestibular long-term potentiation and depression, such as the role of various glutamate receptors and retrograde messengers have been described. The relevant role of the interaction between the platelet-activating factor, acting as a retrograde messenger, and the presynaptic metabotropic glutamate receptors, in determining the full expression of vestibular long-term potentiation is also underlined. In addition, the mechanisms involved in vestibular long-term potentiation have been compared with those leading to long-term potentiation in the hippocampus to emphasize the most significant differences emerging from vestibular studies. The fourth part, describes recent results demonstrating the essential role of nitric oxide, another retrograde messenger, in the induction of vestibular

Bilateral Medial Medullary Stroke: A Challenge in Early Diagnosis

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Amir M. Torabi

2013-01-01

Full Text Available Bilateral medial medullary stroke is a very rare type of stroke, with catastrophic consequences. Early diagnosis is crucial. Here, I present a young patient with acute vertigo, progressive generalized weakness, dysarthria, and respiratory failure, who initially was misdiagnosed with acute vestibular syndrome. Initial brain magnetic resonance imaging (MRI that was done in the acute phase was read as normal. Other possibilities were excluded by lumbar puncture and MRI of cervical spine. MR of C-spine showed lesion at medial medulla; therefore a second MRI of brain was requested, showed characteristic “heart appearance” shape at diffusion weighted (DWI, and confirmed bilateral medial medullary stroke. Retrospectively, a vague-defined hyperintense linear DWI signal at midline was noted in the first brain MRI. Because of the symmetric and midline pattern of this abnormal signal and similarity to an artifact, some radiologists or neurologists may miss this type of stroke. Radiologists and neurologists must recognize clinical and MRI findings of this rare type of stroke, which early treatment could make a difference in patient outcome. The abnormal DWI signal in early stages of this type of stroke may not be a typical “heart appearance” shape, and other variants such as small dot or linear DWI signal at midline must be recognized as early signs of stroke. Also, MRI of cervical spine may be helpful if there is attention to brainstem as well.

Focal increase of blood flow in the cerebral cortex of man during vestibular stimulation

DEFF Research Database (Denmark)

Friberg, L; Olsen, T S; Roland, P E

1985-01-01

This study is an attempt to reveal projection areas for vestibular afferents to the human brain. Changes in regional cerebral blood flow (rCBF) were measured over 254 cortical regions during caloric vestibular stimulation with warm water (44 degrees C). rCBF was measured when the external auditory...... meatus was irrigated with water at body temperature as a control to vestibular stimulation. During vestibular stimulation there was only a single cortical area, located in the superior temporal region, which showed a consistent focal activation in the hemisphere contralateral to the stimulated side...... stimulation that gives rise to the associated conscious vestibular sensation of vertigo....

Molecular composition of extracellular matrix in the vestibular nuclei of the rat.

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Rácz, Eva; Gaál, Botond; Kecskes, Szilvia; Matesz, Clara

2014-07-01

Previous studies have demonstrated that the molecular and structural composition of the extracellular matrix (ECM) shows regional differences in the central nervous system. By using histochemical and immunohistochemical methods, we provide here a detailed map of the distribution of ECM molecules in the vestibular nuclear complex (VNC) of the rat. We have observed common characteristics of the ECM staining pattern in the VNC and a number of differences among the individual vestibular nuclei and their subdivisions. The perineuronal net (PNN), which is the pericellular condensation of ECM, showed the most intense staining for hyaluronan, aggrecan, brevican and tenascin-R in the superior, lateral and medial vestibular nuclei, whereas the HAPLN1 link protein and the neurocan exhibited moderate staining intensity. The rostral part of the descending vestibular nucleus (DVN) presented a similar staining pattern in the PNN, with the exception of brevican, which was negative. The caudal part of the DVN had the weakest staining for all ECM molecules in the PNN. Throughout the VNC, versican staining in the PNN, when present, was distinctive due to its punctuate appearance. The neuropil also exhibited heterogeneity among the individual vestibular nuclei in ECM staining pattern and intensity. We find that the heterogeneous distribution of ECM molecules is associated in many cases with the variable cytoarchitecture and hodological organization of the vestibular nuclei, and propose that differences in the ECM composition may be related to specific neuronal functions associated with gaze and posture control and vestibular compensation.

Transcanal labyrinthectomy for intractable vertigo after unilateral cochlear implantation.

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Heidenreich, Katherine D; Basura, Gregory J; Zwolan, Teresa A; El-Kashlan, Hussam K; Telian, Steven A

2011-10-01

Document the use of transcanal labyrinthectomy to treat disabling attacks of vertigo after unilateral cochlear implantation. A 46-year-old woman with severe-profound bilateral sensorineural hearing loss secondary to enlarged vestibular aqueducts underwent cochlear implantation for her right ear with a Nucleus Freedom device. The surgery was uneventful, and postoperative imaging confirmed that the electrode was positioned properly. She developed episodic vertigo 10 to 14 days after the implant surgery, which failed to improve with aggressive vestibular rehabilitation therapy. Plugging of the round window for possible perilymphatic fistula did not relieve her symptoms. Right transcanal labyrinthectomy supplemented by filling the vestibule with gentamicin-soaked Gelfoam and then a customized vestibular rehabilitation program. Comparison of vestibular symptoms and cochlear implant performance before and after transcanal labyrinthectomy. The patient had immediate relief of symptoms, and the function of the cochlear implant was not adversely affected. Transcanal labyrinthectomy may be an effective method to ablate the vestibular end organ after unilateral cochlear implantation. It can offer relief of disabling vertigo without adversely affecting the performance of the implant.

Posture, head stability, and orientation recovery during vestibular regeneration in pigeons.

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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

Subjective visual horizontal during follow-up after unilateral vestibular deafferentation with gentamicin.

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Tribukait, A; Bergenius, J; Brantberg, K

1998-07-01

The subjective visual horizontal (SVH) was measured by means of a small, rotatable, luminous line in darkness in the upright head and body position and at 10, 20 and 30 degrees of tilt to the right and left before, and repeatedly during a follow-up period of 1 year after intratympanic gentamicin instillations in 12 patients with recurrent vertigo attacks. This treatment caused a loss of the bithermal caloric responses on the diseased side. Shortly after treatment there was a significant tilt of SVH towards the treated side (group mean = 10.6 degrees). Repeated testing made it possible to characterize mathematically the changes with time for SVH. For the group of patients as a whole this otolithic component of vestibular compensation was best described by a power function, SVH = 8.65t(-0.16) degrees, where t is time in days after maximum tilt of SVH. After 1 year, SVH was still significantly tilted towards the treated side (group mean = 3.16 degrees). Gentamicin treatment also caused a significant reduction in the perception of head and body tilt towards the deafferented side, while the perception of tilt towards the healthy side did not show any significant changes. During follow-up there was a gradual improvement in the perception of tilt towards the treated side. However, a significant asymmetry in roll-tilt perception was still present 1 year after deafferentation. There was no correlation between SVH in the upright position and roll-tilt perception, suggesting that these parameters are to some extent dependent on different afferent input from the vestibular organ. They were also found to be complementary for the detection of vestibular disturbance.

Enhancement of Otolith Specific Ocular Responses Using Vestibular Stochastic Resonance

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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

Migraine patients consistently show abnormal vestibular bedside tests

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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.

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

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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.

Distinct roles of Eps8 in the maturation of cochlear and vestibular hair cells.

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Tavazzani, Elisa; Spaiardi, Paolo; Zampini, Valeria; Contini, Donatella; Manca, Marco; Russo, Giancarlo; Prigioni, Ivo; Marcotti, Walter; Masetto, Sergio

2016-07-22

Several genetic mutations affecting the development and function of mammalian hair cells have been shown to cause deafness but not vestibular defects, most likely because vestibular deficits are sometimes centrally compensated. The study of hair cell physiology is thus a powerful direct approach to ascertain the functional status of the vestibular end organs. Deletion of Epidermal growth factor receptor pathway substrate 8 (Eps8), a gene involved in actin remodeling, has been shown to cause deafness in mice. While both inner and outer hair cells from Eps8 knockout (KO) mice showed abnormally short stereocilia, inner hair cells (IHCs) also failed to acquire mature-type ion channels. Despite the fact that Eps8 is also expressed in vestibular hair cells, Eps8 KO mice show no vestibular deficits. In the present study we have investigated the properties of vestibular Type I and Type II hair cells in Eps8-KO mice and compared them to those of cochlear IHCs. In the absence of Eps8, vestibular hair cells show normally long kinocilia, significantly shorter stereocilia and a normal pattern of basolateral voltage-dependent ion channels. We have also found that while vestibular hair cells from Eps8 KO mice show normal voltage responses to injected sinusoidal currents, which were used to mimic the mechanoelectrical transducer current, IHCs lose their ability to synchronize their responses to the stimulus. We conclude that the absence of Eps8 produces a weaker phenotype in vestibular hair cells compared to cochlear IHCs, since it affects the hair bundle morphology but not the basolateral membrane currents. This difference is likely to explain the absence of obvious vestibular dysfunction in Eps8 KO mice. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Brain Activations for Vestibular Stimulation and Dual Tasking Change with Spaceflight

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

Bilateral duplication of the internal auditory canal

International Nuclear Information System (INIS)

Weon, Young Cheol; Kim, Jae Hyoung; Choi, Sung Kyu; Koo, Ja-Won

2007-01-01

Duplication of the internal auditory canal is an extremely rare temporal bone anomaly that is believed to result from aplasia or hypoplasia of the vestibulocochlear nerve. We report bilateral duplication of the internal auditory canal in a 28-month-old boy with developmental delay and sensorineural hearing loss. (orig.)

Hearing impairment caused by mutations in two different genes responsible for nonsyndromic and syndromic hearing loss within a single family.

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Niepokój, Katarzyna; Rygiel, Agnieszka M; Jurczak, Piotr; Kujko, Aleksandra A; Śniegórska, Dominika; Sawicka, Justyna; Grabarczyk, Alicja; Bal, Jerzy; Wertheim-Tysarowska, Katarzyna

2018-02-01

Usher syndrome is rare genetic disorder impairing two human senses, hearing and vision, with the characteristic late onset of vision loss. This syndrome is divided into three types. In all cases, the vision loss is postlingual, while loss of hearing is usually prelingual. The vestibular functions may also be disturbed in Usher type 1 and sometimes in type 3. Vestibular areflexia is helpful in making a proper diagnosis of the syndrome, but, often, the syndrome is misdiagnosed as a nonsyndromic hearing loss. Here, we present a Polish family with hearing loss, which was clinically classified as nonsyndromic. After excluding mutations in the DFNB1 locus, we implemented the next-generation sequencing method and revealed that hearing loss was syndromic and mutations in the USH2A gene indicate Usher syndrome. This research highlights the importance of molecular analysis in establishing a clinical diagnosis of congenital hearing loss.

Catastrophic Antiphospholipid Syndrome Presenting as Bilateral Central Retinal Artery Occlusions

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Steven S. Saraf

2015-01-01

Full Text Available A previously healthy 22-year-old African American woman presented with bilateral vision loss associated with headache. Her ocular examination was significant for bilateral retinal arterial “boxcarring,” retinal whitening, retinal hemorrhages, and cherry red spots. She was diagnosed with bilateral central retinal artery occlusions and was hospitalized due to concomitant diagnosis of stroke and hypercoagulable state. She was also found to be in heart failure and kidney failure. Rheumatology was consulted and she was diagnosed with catastrophic antiphospholipid syndrome in association with systemic lupus erythematosus. Approximately 7 months after presentation, the patient’s vision improved and remained stable at 20/200 and 20/80.

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.

Loss of otolith function with age is associated with increased postural sway measures.

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Serrador, Jorge M; Lipsitz, Lewis A; Gopalakrishnan, Gosala S; Black, F Owen; Wood, Scott J

2009-11-06

Loss of balance and increased fall risk is a common problem associated with aging. Changes in vestibular function occur with aging but the contribution of reduced vestibular otolith function to fall risk remains unknown. We examined a population of 151 healthy individuals (aged 21-93) for both balance (sway measures) and ocular counter-rolling (OCR) function. We assessed balance function with eyes open and closed on a firm surface, eyes open and closed on a foam surface and OCR during +/-20 degree roll tilt at 0.005 Hz. Subjects demonstrated a significant age-related reduction in OCR and increase in postural sway. The effect of age on OCR was greater in females than males. The reduction in OCR was strongly correlated with the mediolateral measures of sway with eyes closed. This correlation was also present in the elderly group alone, suggesting that aging alone does not account for this effect. OCR decreased linearly with age and at a greater rate in females than males. This loss of vestibular otolith-ocular function is associated with increased mediolateral measures of sway which have been shown to be related to increased risk of falls. These data suggest a role for loss of otolith function in contributing to fall risk in the elderly. Further prospective, longitudinal studies are necessary to confirm these findings.

Vestibular lesion-induced developmental plasticity in spinal locomotor networks during Xenopus laevis metamorphosis.

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Beyeler, Anna; Rao, Guillaume; Ladepeche, Laurent; Jacques, André; Simmers, John; Le Ray, Didier

2013-01-01

During frog metamorphosis, the vestibular sensory system remains unchanged, while spinal motor networks undergo a massive restructuring associated with the transition from the larval to adult biomechanical system. We investigated in Xenopus laevis the impact of a pre- (tadpole stage) or post-metamorphosis (juvenile stage) unilateral labyrinthectomy (UL) on young adult swimming performance and underlying spinal locomotor circuitry. The acute disruptive effects on locomotion were similar in both tadpoles and juvenile frogs. However, animals that had metamorphosed with a preceding UL expressed restored swimming behavior at the juvenile stage, whereas animals lesioned after metamorphosis never recovered. Whilst kinematic and electrophysiological analyses of the propulsive system showed no significant differences in either juvenile group, a 3D biomechanical simulation suggested that an asymmetry in the dynamic control of posture during swimming could account for the behavioral restoration observed in animals that had been labyrinthectomized before metamorphosis. This hypothesis was subsequently supported by in vivo electromyography during free swimming and in vitro recordings from isolated brainstem/spinal cord preparations. Specifically, animals lesioned prior to metamorphosis at the larval stage exhibited an asymmetrical propulsion/posture coupling as a post-metamorphic young adult. This developmental alteration was accompanied by an ipsilesional decrease in propriospinal coordination that is normally established in strict left-right symmetry during metamorphosis in order to synchronize dorsal trunk muscle contractions with bilateral hindlimb extensions in the swimming adult. Our data thus suggest that a disequilibrium in descending vestibulospinal information during Xenopus metamorphosis leads to an altered assembly of adult spinal locomotor circuitry. This in turn enables an adaptive compensation for the dynamic postural asymmetry induced by the vestibular imbalance

Purchase decision-making is modulated by vestibular stimulation.