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1

[Activity of premotor vestibular neurons in the alert cat  

UK PubMed Central (United Kingdom)

The activity of medial vestibular nucleus neurons projecting to the contralateral abducens nucleus (premotor vestibular neurons) has been recorded during spontaneous and vestibular induced eye movements in the alert cat. Recorded neurons were identified by their antidromic activation from the abducens nucleus and by the post-synaptic field potential induced in this nucleus. The activity of identified medial vestibular neurons increased significantly with horizontal eye position and velocity toward the contralateral side, and decreased abruptly during ipsilateral saccades. The activity of these neurons was also related to head velocity toward the ipsilateral side. The functional role and origin of eye position and velocity signals present in these vestibular neurons are discussed.

Escudero M; de la Cruz RR

1989-06-01

2

Investigation of seasonal variability of vestibular neuronitis.  

UK PubMed Central (United Kingdom)

Objective: To determine if the incidence of vestibular neuronitis displays seasonal variation. Methods: A retrospective case review was performed to determine the monthly and quarterly incidence of vestibular neuronitis over a 36-month period. Incidence values were compiled, and the chi-square test and Rayleigh test for circular means were used to assess for uneven distribution and seasonality, respectively. Results: Fifty-two patients were diagnosed with vestibular neuronitis during the study period. The 2009-2010 study year showed uneven distribution and evidence of seasonality (R = 7.211, p < 0.001). However, the other two study years did not show statistical significance using either the chi-square test or Rayleigh test. In addition, when incidence values were aggregated across all three years of the study, neither the chi-square test nor Rayleigh test showed statistical significance. Conclusion: The present study found minimal evidence of seasonality in the incidence of vestibular neuronitis. These findings are consistent with studies of seasonality observed for other inner-ear disorders thought to be virally mediated.

Koors PD; Thacker LR; Coelho DH

2013-09-01

3

The distribution of vestibular efferent neurons receiving innervation of secondary vestibular afferent nerves in rats.  

UK PubMed Central (United Kingdom)

OBJECTIVES/HYPOTHESIS: To explore the innervation areas of the medial vestibular nucleus (MVN) afferent neurons onto vestibular efferent neurons in the brain stem of rats. STUDY DESIGN: A morphology study in the central vestibular system. METHODS: Two neuronal tracers were used. Lectin PHA-L Conjugates (PHA-L, Invitrogen L - 11270,) was injected into the MVN as an anterograde tracer, and 5% FluoSpheres carboxylate-modified microspheres (MFS, Molecular Probe F-8793) was injected into the contralateral peripheral vestibule using as a retrograde tracer. All animals were allowed to recover for 12 days to facilitate sufficient transportation of the tracers. Then brain stems were sliced coronally on a freezing microtome and observed under a fluorescence microscope and laser confocal microscopy. RESULTS: Neurons in the MVN labeled with PHA-L exhibited green fluorescence, and their axons were distributed near the genu of the facial nerve (g7) and in the reticulation structure, as well as in the cerebellum or oculomotor-related nuclei. Neurons labeled with red fluorescence of MFS were mainly located dorsomedial and dorsolateral to g7 and in the caudal pontine reticular nucleus (PnC) bilaterally and presented different morphologies at different locations. The synaptic junctions would display color overlap (fluoresced yellow). Under three-dimensional reconstruction of the confocal laser microscopy, the synaptic junctions were visualized dorsomedial and dorsolateral to g7 bilaterally, predominantly ipsilateral to the MVN injection site. CONCLUSIONS: Morphologic evidence of the distribution of vestibular efferent neurons synapsed by afferent nerves from MVN was demonstrated. These efferent neurons constitute short closed-loop circuits with neurons in the MVN.

Wang J; Chi FL; Xin Y; Regner MF

2013-05-01

4

[Morphologic and electrophysiologic characteristics of cultured vestibular ganglia neurons].  

UK PubMed Central (United Kingdom)

Vestibular afferent neurons have been classified on the basis of their spontaneous activity as regular and irregular; this has been attributed to their synaptic input, but it remains to be defined the participation of some intrinsical properties of the afferent neurons in the determination of their discharge pattern. In this work, we have developed tissue cultures of the rat vestibular ganglia. Isolated cells were plated using poly-D-lysine or collagen as substrates and L-15 or Neurobasal as culture media. After 48 hrs cells in the four experimental conditions give forth neurites of variable longitude. By using antibodies against the neurofilaments 160 kDa the cell structure was studied. Monopolar (30.6%), bipolar (63.9%) and multipolar (5.5%) cells were found. By using the voltage and current clamp procedures the voltage dependence and kinetics of the tetrodotoxin sensitive Na+ current was fully characterized. Cultured cells were shown to generate action potentials under electrical stimulation, and they were capable of repetitive spike discharge under the influence of 4-aminopyridine. These results demonstrate that tissue cultures constitute an excellent system to study the intrinsical properties of vestibular afferent neurons.

Soto E; Limón A; Ortega A; Vega R

2002-01-01

5

Responses of Central Vestibular Neurons to Sinusoidal Yaw Rotation in Compensated Macaques after Unilateral Labyrinthectomy.  

UK PubMed Central (United Kingdom)

After vestibular labyrinth injury, behavioral measures of vestibular function partially recover through the process of vestibular compensation. The current study was performed to improve our understanding of the physiology of macaque vestibular nucleus neurons in the compensated state (>6 weeks) after unilateral labyrinthectomy (UL). The responses of neurons to sinusoidal yaw rotation at a series of frequencies (0.1 - 2.0Hz) and peak velocities (7.5 - 210°/s) were examined to determine how the behavior of these cells differed from those in animals with intact labyrinths. The sensitivity of neurons responding to ipsilateral rotation (type I) did not differ between the intact and injured sides after UL, though this sensitivity was lower bilaterally after lesion than pre-lesion. The sensitivity of neurons that increase firing with contralateral rotation (type II) was higher ipsilateral to the UL than pre-lesion or in the nucleus contralateral to the UL. UL did not increase asymmetry in the responses of individual type I or II neurons to ipsilateral vs. contralateral rotation, nor does it change the power law relationship between neuronal firing and level of stimulation. Increased sensitivities of contralesional type I neurons to the remaining vestibular nerve input and increased efficacy of inhibitory vestibular commissures projecting to the ipsilesional vestibular nucleus appear responsible for recovery of dynamic function of central vestibular neurons in compensated animals. The portion of type I neurons on the ipsilesional side is reduced in compensated animals, which likely accounts for the asymmetries in vestibular reflexes and perception that characterize vestibular function after UL.

Newlands SD; Wei M

2013-07-01

6

Infrared laser stimulation of retinal and vestibular neurons  

Science.gov (United States)

The study of laser-neuron interaction has gained interest over the last few years not only for understanding of fundamental mechanisms but also for medical applications such as prosthesis because of the non-invasive characteristic of the laser stimulation. Several authors have shown that near infrared lasers are able to stimulate neurons. It is suggested that a thermal gradient induced by the absorption of the laser radiation on cells is the primary effect but the exact mechanism remains unclear. We show in this work that infrared laser radiations provide a possible way for stimulating retinal and vestibular ganglion cells. We describe relevant physical characteristics allowing safe and reproducible neuron stimulations by single infrared pulses. Calcium fluorescence imaging and electrophysiological recordings have been used to measure ionic exchanges at the neuron membrane. The stimulation system is based on a pulsed laser diode beam of a few mW. Effects of three different wavelengths (from 1470 to 1875 nm) and stimulation durations have been investigated. Variations of the stimulation energy thresholds suggest that the main physical parameter is the water optical absorption. Measurements of the temperature at the cell membrane show that a constant temperature rise is required to stimulate neurons, suggesting a photothermal process.

Bardin, Fabrice; Bec, Jean-Michel; Albert, Emmanuelle S.; Hamel, Christian; Dupeyron, Gérard; Chabbert, Christian; Marc, Isabelle; Dumas, Michel

2011-02-01

7

Responses of vestibular nucleus neurons to inputs from the hindlimb are enhanced following a bilateral labyrinthectomy.  

UK PubMed Central (United Kingdom)

Vestibular nucleus neurons have been shown to respond to stimulation of afferents innervating the limbs. However, a limitation in the potential translation of these findings is that they were obtained from decerebrate or anesthetized animals. The goal of the present study was to determine whether stimulation of hindlimb nerves similarly affects vestibular nucleus neuronal activity in conscious cats, and whether the responsiveness of neurons to the stimuli is altered following a bilateral labyrinthectomy. In labyrinth-intact animals, the firing rate of 24/59 (41%) of the neurons in the caudal vestibular nucleus complex was affected by hindlimb nerve stimulation. Most responses were excitatory; the median response latency was 20 ms, but some units had response latencies as short as 10 ms. In the first week after a bilateral labyrinthectomy, the proportion of vestibular nucleus neurons that responded to hindlimb nerve stimulation increased slightly (to 24/55 or 44% of units). However, during the subsequent postlabyrinthectomy survival period, the proportion of vestibular nucleus neurons with hindlimb inputs increased significantly (to 30/49 or 61% of units). Stimuli to hindlimb nerves needed to elicit neuronal responses was consistently over three times the threshold for eliciting an afferent volley. These data show that inputs from hindlimb afferents smaller than those innervating muscle spindles and Golgi tendon organs affect the processing of information in the vestibular nuclei, and that these inputs are enhanced following a bilateral labyrinthectomy. These findings have implications for the development of a limb neuroprosthetics device for the management of bilateral vestibular loss.

McCall AA; Moy JD; Puterbaugh SR; DeMayo WM; Yates BJ

2013-03-01

8

FMRFamide-related peptide expression in the vestibular-afferent neurons.  

UK PubMed Central (United Kingdom)

Vestibular-afferent neurons innervate hair cells from the sensory epithelia of vestibular end-organs and their action-potential discharge dynamics are driven by linear and angular accelerations of the head. The electrical activity of the vestibular-afferent neurons depends on their intrinsic properties and on the synaptic input from hair cells and from the terminals of the efferent system. Here we report that vestibular-afferent neurons of the rat are immunoreactive to RFamide-related peptides, and that the stronger signal comes from calyx-shaped neuron dendrites, with no signal detected in hair cells or supporting cells. The whole-cell voltage clamp recording of isolated afferent neurons showed that they express robust acid-sensing ionic currents (ASICs). Extracellular multiunit recordings of the vestibular nerve in a preparation in vitro of the rat inner ear showed that the perfusion of FMRFamide (a snail ortholog of this family of neuropeptides) exerts an excitatory effect on the afferent-neurons spike-discharge rate. Because the FMRFamide cannot activate the ASIC but reduces its desensitization generating a more robust current, its effect indicates that the ASIC are tonically active in the vestibular-afferent neurons and modulated by RFamide-like peptides.

Mercado F; López I; Ortega A; Almanza A; Soto E; Vega R

2012-03-01

9

Tests of linearity in the responses of eye-movement-sensitive vestibular neurons to sinusoidal yaw rotation.  

UK PubMed Central (United Kingdom)

The rotational vestibulo-ocular reflex in primates is linear and stabilizes gaze in space over a large range of head movements. Best evidence suggests that position-vestibular-pause (PVP) and eye-head velocity (EHV) neurons in the vestibular nuclei are the primary mediators of vestibulo-ocular reflexes for rotational head movements, yet the linearity of these neurons has not been extensively tested. The current study was undertaken to understand how varying magnitudes of yaw rotation are coded in these neurons. Sixty-six PVP and 41 EHV neurons in the rostral vestibular nuclei of 7 awake rhesus macaques were recorded over a range of frequencies (0.1 to 2 Hz) and peak velocities (7.5 to 210°/s at 0.5 Hz). The sensitivity (gain) of the neurons decreased with increasing peak velocity of rotation for all PVP neurons and EHV neurons sensitive to ipsilateral rotation (type I). The sensitivity of contralateral rotation-sensitive (type II) EHV neurons did not significantly decrease with increasing peak velocity. These data show that, like non-eye-movement-related vestibular nuclear neurons that are believed to mediate nonlinear vestibular functions, PVP neurons involved in the linear vestibulo-ocular reflex also behave in a nonlinear fashion. Similar to other sensory nuclei, the magnitude of the vestibular stimulus is not linearly coded by the responses of vestibular neurons; rather, amplitude compression extends the dynamic range of PVP and type I EHV vestibular neurons.

Newlands SD; Wei M

2013-05-01

10

Asymmetric responses to rotation at high frequencies in central vestibular neurons of the alert cat.  

Science.gov (United States)

The horizontal rotatory vestibulo-ocular reflex (VOR) stabilizes gaze by moving the eyes at an angular velocity proportional to head velocity, and can accomplish this for a broad range of frequencies and amplitudes of head motion. Rotation at 5 Hz and above may be processed differently than lower frequencies by the VOR network. We recorded discharges and calculated spike densities of a small sample of vestibular neurons in alert cats during low-velocity rotation at frequencies up to 8 Hz. At high frequencies, we found both vestibular-only (V-only) and eye-movement-sensitive (EM) cells that generated asymmetric output signals. Asymmetry was primarily of the cutoff type, i.e., changes in spike density were smallest for rotation in the inhibitory direction. Most cells were identified as secondary neurons. The mean spike density was 23 sp/s, which was lower than previously reported in vestibular neurons of monkeys. A few neurons had very high sensitivities, associated with phase-locking, to rotation at high frequencies. In general, vestibular neurons carried a high-pass-filtered version of rotational signals. When synaptic inputs from the vestibular commissure were quantified, we found that the immediate change in probability of firing due to commissural vestibular input was inversely correlated with the degree of high-pass filtering. At high frequencies, increased asymmetry and phase-locking occurred in some neurons. A small number of neurons responded with increased probability of firing to both directions of rotation. Together, these observations suggest that high frequencies of rotation may be encoded differently than low frequencies by central vestibular neurons in alert animals. PMID:15044073

Broussard, Dianne M; Priesol, Adrian J; Tan, Yao-Fang

2004-04-16

11

Responses of vestibular nucleus neurons to inputs from the hindlimb are enhanced following a bilateral labyrinthectomy.  

Science.gov (United States)

Vestibular nucleus neurons have been shown to respond to stimulation of afferents innervating the limbs. However, a limitation in the potential translation of these findings is that they were obtained from decerebrate or anesthetized animals. The goal of the present study was to determine whether stimulation of hindlimb nerves similarly affects vestibular nucleus neuronal activity in conscious cats, and whether the responsiveness of neurons to the stimuli is altered following a bilateral labyrinthectomy. In labyrinth-intact animals, the firing rate of 24/59 (41%) of the neurons in the caudal vestibular nucleus complex was affected by hindlimb nerve stimulation. Most responses were excitatory; the median response latency was 20 ms, but some units had response latencies as short as 10 ms. In the first week after a bilateral labyrinthectomy, the proportion of vestibular nucleus neurons that responded to hindlimb nerve stimulation increased slightly (to 24/55 or 44% of units). However, during the subsequent postlabyrinthectomy survival period, the proportion of vestibular nucleus neurons with hindlimb inputs increased significantly (to 30/49 or 61% of units). Stimuli to hindlimb nerves needed to elicit neuronal responses was consistently over three times the threshold for eliciting an afferent volley. These data show that inputs from hindlimb afferents smaller than those innervating muscle spindles and Golgi tendon organs affect the processing of information in the vestibular nuclei, and that these inputs are enhanced following a bilateral labyrinthectomy. These findings have implications for the development of a limb neuroprosthetics device for the management of bilateral vestibular loss. PMID:23305979

McCall, Andrew A; Moy, Jennifer D; Puterbaugh, Sonya R; DeMayo, William M; Yates, Bill J

2013-01-10

12

Central compensation of vestibular deficits. IV. Responses of lateral vestibular neurons to neck rotation after labyrinth deafferentation.  

UK PubMed Central (United Kingdom)

The response characteristics of neurons located in the lateral vestibular nucleus (LVN) to neck rotation at 0.026 Hz, 10 degrees peak displacement, have been investigated in precollicular decerebrate cats submitted to ipsilateral acute (aVN) or chronic vestibular neurectomy (cVN). On the whole, 105 units were tested after aVN (i.e., during the first postoperative hours) and 132 units after cVN (i.e., after full compensation of the postural and locomotor deficits). The neurons were histologically located either in the rostroventral (rvLVN) or the dorsocaudal part (dcLVN) of Deiters' nucleus, which are known to project mainly to the cervical and the lumbosacral cord, respectively. Moreover, 55 units in the former group and 66 units in the latter group were identified as vestibulospinal neurons projecting to lumbosacral segments of the spinal cord. The responses of these 237 LVN neurons to the neck input were then compared with those of 120 LVN neurons recorded previously in decerebrate cats with intact labyrinths. Whereas 58.3% of the LVN units recorded in control experiments were responsive to neck rotation, 69.5% of the units were affected by this stimulation at the acute stage of the neurectomy and 74.2% at the chronic stage. This increase in responsive units after aVN and cVN with respect to the controls was found exclusively in the dcLVN. The mean discharge rate of the responsive LVN neurons decreased from 40.7 +/- 48.9 (SD) imp/s in control experiments to 22.1 +/- 15.8 (SD) imp/s after a VN. Similar value was also obtained after cVN [25.0 +/- 17.2 (SD) imp/s], suggesting that compensation of the postural deficits elicited by the vestibular neurectomy results from a redistribution of the excitatory drive within different populations of LVN neurons. Indeed, the relation found in control experiments, i.e., that the faster the conduction velocity of vestibulospinal axons the lower was the unit discharge at rest, was lost after aVN, due to a decrease in resting discharge of the slow units. The mean discharge rate of the slow units, however, recovered after cVN, so that the negative correlation between resting discharge rate and axonal conduction velocity was reestablished. The average gain and sensitivity of the first harmonic response of the LVN neurons to neck rotation recorded after aVN and cVN were comparable to those obtained in preparations with the vestibular nerves intact.(ABSTRACT TRUNCATED AT 400 WORDS)

Xerri C; Gianni S; Manzoni D; Pompeiano O

1985-10-01

13

Potent effects of a selective cannabinoid receptor agonist on some guinea pig medial vestibular nucleus neurons.  

UK PubMed Central (United Kingdom)

Binding studies have indicated that the density of the cannabinoid CB, receptor is very low in the vestibular nucleus complex compared to other areas of the central nervous system (CNS), suggesting that CB1 receptors may have little functional significance for the vestibular nucleus. However, the dizziness often produced by cannabis suggests that the vestibular system may be implicated. We investigated the effects of the selective CB1 receptor agonist, CP 55940 (the levorotatory enantiomer of desacetyllevonantradol), on medial vestibular nucleus neurons in guinea pig brainstem slices in vitro. Only 3/18 medial vestibular nucleus neurons tested with 1 microM CP 55940 showed changes in firing rate, however these were decreases with an average magnitude of 72.3%; 3/4 neurons tested with 10 microM CP 55940 showed decreases with an average magnitude of 92.7% (P < 0.05 in both cases). In all cases the effects of CP 55940 were long-lasting. These results suggest that despite the low density of CB1 receptors in the vestibular nucleus complex, they may be of functional significance for the behavioural effects of cannabis use.

Newsham-West D; Darlington CL; Smith PF

1998-05-01

14

Postnatal expression of TrkB receptor in rat vestibular nuclear neurons responsive to horizontal and vertical linear accelerations.  

UK PubMed Central (United Kingdom)

We examined the maturation expression profile of tyrosine kinase B (TrkB) receptor in rat vestibular nuclear neurons that were activated by sinusoidal linear acceleration along the horizontal or vertical axis. The otolithic origin of Fos expression in these neurons was confirmed with labyrinthectomized controls and normal controls, which showed only sporadically scattered Fos-labeled neurons in the vestibular nucleus. In P4-6 test rats, no Fos-labeled neurons were found in the vestibular nucleus, but the medial and spinal vestibular neurons showed weak immunoreactivity for TrkB. The intensity of TrkB immunoreactivity in vestibular nuclear neurons progressively increased in the second postnatal week but remained low in adults. From P7 onward, TrkB-expressing neurons responded to horizontal or vertical otolithic stimulation with Fos expression. The number of Fos-labeled vestibular nuclear neurons expressing TrkB increased with age, from 13-43% in P7 rats to 85-90% in adult rats. Our results therefore suggest that TrkB/neurotrophin signaling plays a dominant role in modulating vestibular nuclear neurons for the coding of gravity-related horizontal head movements and for the regulation of vestibular-related behavior during postnatal development.

Ma CW; Zhang FX; Lai CH; Lai SK; Yung KK; Shum DK; Chan YS

2013-02-01

15

[Synaptic action of vestibular nerve afferents on reticular neurons of the isolated medulla oblongata of the goldfish  

UK PubMed Central (United Kingdom)

Excitatory post-synaptic potentials (EPSPs) were evoked in reticular neurons of isolated goldfish brian stem by stimulation of the ipsilateral vestibular nerve or by direct intra-axonal activation of single vestibular fibres. Composite EPSPs displayed usually two components. Ca2+-deficient, Mn2+-containing solution abolished the delayed chemical components of EPSPs, but did not affect the short latency responses suggesting dual (electrical-chemical) mode of transmission between some vestibular afferents and reticular neurons.

Kozhanov VM; Shapovalov AI

1985-01-01

16

Choice-related activity and correlated noise in subcortical vestibular neurons.  

UK PubMed Central (United Kingdom)

Functional links between neuronal activity and perception are studied by examining trial-by-trial correlations (choice probabilities) between neural responses and perceptual decisions. We addressed fundamental issues regarding the nature and origin of choice probabilities by recording from subcortical (brainstem and cerebellar) neurons in rhesus monkeys during a vestibular heading discrimination task. Subcortical neurons showed robust choice probabilities that exceeded those seen in cortex (area MSTd) under identical conditions. The greater choice probabilities of subcortical neurons could be predicted by a stronger dependence of correlated noise on tuning similarity, as revealed by population decoding. Significant choice probabilities were observed almost exclusively for neurons that responded selectively to translation, whereas neurons that represented net gravito-inertial acceleration did not show choice probabilities. These findings suggest that the emergence of choice probabilities in the vestibular system depends on a critical signal transformation that occurs in subcortical pathways to distinguish translation from orientation relative to gravity.

Liu S; Gu Y; DeAngelis GC; Angelaki DE

2013-01-01

17

Central compensation of vestibular deficits. III. Response characteristics of lateral vestibular neurons to roll tilt after contralateral labyrinth deafferentation.  

UK PubMed Central (United Kingdom)

The responses of lateral vestibular nucleus (LVN) neurons to stimulation of macular labyrinth receptors have been investigated in precollicular decerebrate cats after contralateral acute vestibular neurectomy (aVN). On the whole, 78 LVN neurons were tested during slow sinusoidal tilt of the animal at the standard parameters (0.026 Hz, 10 degrees peak displacement). The neurons were located in both the rostroventral (rvLVN) and the dorsocaudal parts (dcLVN) of Deiters' nucleus, which project mainly to the cervical and the lumbosacral cord, respectively. After contralateral aVN, the proportions of responsive units in rvLVN and dcLVN (100% and 75.4%, respectively) were similar to those obtained in control experiments with intact labyrinths. However, the mean discharge rate of the responsive units slightly decreased with respect to the value obtained in control experiments, the decrease being more prominent within the rvLVN. The average sensitivity (and to a lesser extent the gain) of responses of rvLVN neurons to the labyrinth input was almost twice that of the dcLVN units in preparations with the vestibular nerves intact; these regional differences disappeared after contralateral aVN, particularly due to a decrease in gain and sensitivity of responses in the rvLVN. The proportion of LVN neurons that were maximally excited by animal position increased from 74.0% in the control experiments to 82.8%. However, while in control experiments the proportion of units excited during side-down tilt was twice as high as that of the units excited by side-up tilt, the opposite occurred after contralateral aVN; this finding affected particularly the dcLVN. In addition the average phase lead of responses relative to the extreme animal displacements slightly decreased from +12.3 degrees in control experiments to +9.4 degrees. Among the LVN neurons recorded after contralateral aVN, 35 were antidromically activated by stimulating the spinal cord at T12 L1, while 43 units were not activated. The relation found in control experiments, i.e., that the faster the conduction velocity of vestibulospinal axon the lower was the unit discharge at rest, was lost after contralateral aVN, due to a decrease in resting discharge rate of the slow neurons. This finding, coupled with the observation that slow and fast units did not show any difference in their response gain to tilt, explains why the positive correlation between axonal conduction velocity and response sensitivity occurring in control experiments was lost after contralateral aVN.(ABSTRACT TRUNCATED AT 400 WORDS)

Lacour M; Manzoni D; Pompeiano O; Xerri C

1985-10-01

18

Molecular developmental neurobiology of formation, guidance and survival of primary vestibular neurons  

Science.gov (United States)

Untangling the molecular and physiological interactions that generate the proper connections of the primary vestibular neurons in normal gravity requires two parallel approaches. One approach needs to use mutant mice to delineate the molecular basis of developmental mechanisms that govern ear development, including formation and differentiation of neurons and establishment of their peripheral and central connections. Beyond that and in addition to it, we need physiological investigations using microgravity and/or hypergravity, as well as absence of otoconia, to understand the role played by vestibular stimuli to fine tune connections of primary and secondary vestibular neurons. This paper provides an overview of some of the molecular mechanisms uncovered over the last few years that guide development, differentiation and survival of primary vestibular neurons of the mammalian ear. Briefly, several genes that are essential for primary neuron formation have been identified, all genes that govern embryonic survival are known and the first genes and mechanisms that guide formation of proper connections are being revealed. While still incomplete, the progress has been astounding and the completion of the mouse genome project will further accelerate the pace. Such data pave the way to put the research on the influence of altered gravity stimulation within a molecular framework.

Fritzsch, B.

2003-10-01

19

Heterogeneous potassium conductances contribute to the diverse firing properties of postnatal mouse vestibular ganglion neurons.  

Science.gov (United States)

How mechanical information is encoded in the vestibular periphery has not been clarified. To begin to address the issue we examined the intrinsic firing properties of postnatal mouse vestibular ganglion neurons using the whole cell, tight-seal technique in current-clamp mode. We categorized two populations of neurons based on the threshold required to evoke an action potential. Low-threshold neurons fired with an average minimum current injection of -43 pA, whereas high-threshold neurons required -176 pA. Using sine-wave stimuli, we found that the neurons were inherently tuned with best frequencies that ranged up to 40 Hz. To investigate the membrane properties that contributed to the variability in firing properties we examined the same neurons in voltage-clamp mode. High-threshold neurons had larger cell bodies and whole cell capacitances but a resting conductance density of 0.18 nS/pF, nearly identical to that of low-threshold neurons, suggesting that cell size was an important parameter determining threshold. We also found that vestibular ganglion neurons expressed a heterogeneous population of potassium conductances. TEA-sensitive conductances contributed to the position of the tuning curve in the frequency domain. A 4-AP-sensitive conductance was active at rest and hyperpolarized resting potential, limited spontaneous activity, raised threshold, and prevented repetitive firing. In response to sine-wave stimulation 4-AP-sensitive conductances prevented action potential generation at low frequencies and thus contributed to the high-pass corner of the tuning curve. The mean low-pass corner (about 29 Hz) was determined by the membrane time constant. Together these factors contributed to the sharply tuned, band-pass characteristics intrinsic to postnatal vestibular ganglion neurons. PMID:16855108

Risner, Jessica R; Holt, Jeffrey R

2006-07-19

20

Heterogeneous potassium conductances contribute to the diverse firing properties of postnatal mouse vestibular ganglion neurons.  

UK PubMed Central (United Kingdom)

How mechanical information is encoded in the vestibular periphery has not been clarified. To begin to address the issue we examined the intrinsic firing properties of postnatal mouse vestibular ganglion neurons using the whole cell, tight-seal technique in current-clamp mode. We categorized two populations of neurons based on the threshold required to evoke an action potential. Low-threshold neurons fired with an average minimum current injection of -43 pA, whereas high-threshold neurons required -176 pA. Using sine-wave stimuli, we found that the neurons were inherently tuned with best frequencies that ranged up to 40 Hz. To investigate the membrane properties that contributed to the variability in firing properties we examined the same neurons in voltage-clamp mode. High-threshold neurons had larger cell bodies and whole cell capacitances but a resting conductance density of 0.18 nS/pF, nearly identical to that of low-threshold neurons, suggesting that cell size was an important parameter determining threshold. We also found that vestibular ganglion neurons expressed a heterogeneous population of potassium conductances. TEA-sensitive conductances contributed to the position of the tuning curve in the frequency domain. A 4-AP-sensitive conductance was active at rest and hyperpolarized resting potential, limited spontaneous activity, raised threshold, and prevented repetitive firing. In response to sine-wave stimulation 4-AP-sensitive conductances prevented action potential generation at low frequencies and thus contributed to the high-pass corner of the tuning curve. The mean low-pass corner (about 29 Hz) was determined by the membrane time constant. Together these factors contributed to the sharply tuned, band-pass characteristics intrinsic to postnatal vestibular ganglion neurons.

Risner JR; Holt JR

2006-11-01

 
 
 
 
21

Intrinsic physiology of identified neurons in the prepositus hypoglossi and medial vestibular nuclei.  

Science.gov (United States)

Signal processing in the vestibular system is influenced by the intrinsic physiological properties of neurons that differ in neurotransmitters and circuit connections. Do membrane and firing properties differ across functionally distinct cell types? This study examines the intrinsic physiology of neurons in the medial vestibular nucleus (MVN) and nucleus prepositus hypoglossi (NPH) which express different neurotransmitters and have distinct axonal projections. NPH neurons expressing fluorescent proteins in glutamatergic, glycinergic, or GABAergic neurons were targeted for whole-cell patch recordings in brainstem slices obtained from transgenic mouse lines (YFP-16, GlyT2, and GIN). Recordings from MVN neurons projecting to the spinal cord, reticular formation, or oculomotor nucleus were obtained by targeting fluorescent neurons retrogradely labeled from tracer injections. Intrinsic physiological properties of identified neurons exhibited continuous variations but tended to differ between functionally defined cell types. Within the NPH, YFP-16 neurons had the narrowest action potentials and highest evoked firing rates and expressed high levels of Kv3.3 proteins, which speed repolarization. MVN neurons projecting to the spinal cord and oculomotor nucleus had similar action potential waveforms, but oculomotor-projecting neurons had higher intrinsic gains than those projecting to the spinal cord. These results indicate that intrinsic membrane properties are differentially tuned in MVN and NPH neurons subserving different functions. PMID:21422541

Kolkman, Kristine E; Moghadam, Setareh H; du Lac, Sascha

2011-01-01

22

Responses of neurons in the caudal medullary lateral tegmental field to visceral inputs and vestibular stimulation in vertical planes.  

UK PubMed Central (United Kingdom)

The dorsolateral reticular formation of the caudal medulla, or the lateral tegmental field (LTF), has been classified as the brain's "vomiting center", as well as an important region in regulating sympathetic outflow. We examined the responses of LTF neurons in cats to rotations of the body that activate vestibular receptors, as well as to stimulation of baroreceptors (through mechanical stretch of the carotid sinus) and gastrointestinal receptors (through the intragastric administration of the emetic compound copper sulfate). Approximately half of the LTF neurons exhibited graviceptive responses to vestibular stimulation, similar to primary afferents innervating otolith organs. The other half of the neurons had complex responses, including spatiotemporal convergence behavior, suggesting that they received convergent inputs from a variety of vestibular receptors. Neurons that received gastrointestinal and baroreceptor inputs had similar complex responses to vestibular stimulation; such responses are expected for neurons that contribute to the generation of motion sickness. LTF units with convergent baroreceptor and vestibular inputs may participate in producing the cardiovascular system components of motion sickness, such as the changes in skin blood flow that result in pallor. The administration of copper sulfate often modulated the gain of responses of LTF neurons to vestibular stimulation, particularly for units whose spontaneous firing rate was altered by infusion of drug (median of 459%). The present results raise the prospect that emetic signals from the gastrointestinal tract modify the processing of vestibular inputs by LTF neurons, thereby affecting the probability that vomiting will occur as a consequence of motion sickness.

Moy JD; Miller DJ; Catanzaro MF; Boyle BM; Ogburn SW; Cotter LA; Yates BJ; McCall AA

2012-11-01

23

Visual sensory substitution in vestibular compensation: neuronal substrates in the alert cat.  

UK PubMed Central (United Kingdom)

The purpose of this study was to investigate adaptive changes in the activity of vestibular nuclei neurons unilaterally deprived of their primary afferent inputs when influenced by visual motion cues. These neuronal changes might account for the established role that vision plays in the compensation for posturo-kinetic deficits after the loss of vestibular inputs. Neuronal recordings were made in alert, non-paralysed cats that had undergone unilateral vestibular nerve sections. The unit responses collected in both Deiters' nuclei were compared to those previously recorded in intact cats. We analysed the extracellular activity of Deiters' nucleus neurons, as well as the optokinetic reflex (OKR) evoked during sinusoidal translation of a whole-field optokinetic stimulus in the vertical plane. In intact cats, we found the unit firing rate closely correlated with the visual surround translation velocity, and the relationship between the discharge rate and the motion frequency was tuned around an optimal frequency. The maximum firing rate modulation was generally below the 0.25 Hz stimulus frequency; unit responses were weak or even absent above 0.25 Hz. From the 4th day to the end of the 3rd week after ipsilateral deafferentation, a majority of cells was found to display maximum discharge modulation during vertical visual stimulation at 0.50 Hz, and even at 0.75 Hz, indicating that the frequency bandwidth of the visually induced responses of deafferented vestibular nuclei neurons had been extended. Consequently, the frequency-dependent attenuation in the sensitivity of vestibular neurons to visual inputs was much less pronounced. After the first 3 weeks post-lesion, the unit response characteristics were very similar to those observed prior to the deafferentation. On the nucleus contralateral to the neurectomy, the maximum modulation of most cells was tuned to the low frequencies of optokinetic stimulation, as also seen prior to the lesion. We found, however, a subgroup of cells displaying well-developed responses above 0.50 Hz. Under all experimental conditions, the neuronal response phase still remained closely correlated with the motion velocity of the vertical sinusoidal visual pattern. We hypothesize that Deiters' neurons deprived of their primary afferents may transiently acquire the ability to code fast head movements on the basis of visual messages, thus compensating, at least partially, for the loss of dynamic vestibular inputs during the early stages of the recovery process.(ABSTRACT TRUNCATED AT 400 WORDS)

Zennou-Azogui Y; Xerri C; Harlay F

1994-01-01

24

Integrative responses of neurons in nucleus tractus solitarius to visceral afferent stimulation and vestibular stimulation in vertical planes.  

Science.gov (United States)

Anatomical studies have demonstrated that the vestibular nuclei project to nucleus tractus solitarius (NTS), but little is known about the effects of vestibular inputs on NTS neuronal activity. Furthermore, lesions of NTS abolish vomiting elicited by a variety of different triggering mechanisms, including vestibular stimulation, suggesting that emetic inputs may converge on the same NTS neurons. As such, an emetic stimulus that activates gastrointestinal (GI) receptors could alter the responses of NTS neurons to vestibular inputs. In the present study, we examined in decerebrate cats the responses of NTS neurons to rotations of the body in vertical planes before and after the intragastric administration of the emetic compound copper sulfate. The activity of more than one-third of NTS neurons was modulated by vertical vestibular stimulation, with most of the responsive cells having their firing rate altered by rotations in the head-up or head-down directions. These responses were aligned with head position in space, as opposed to the velocity of head movements. The activity of NTS neurons with baroreceptor, pulmonary, and GI inputs could be modulated by vertical plane rotations. However, injection of copper sulfate into the stomach did not alter the responses to vestibular stimulation of NTS neurons that received GI inputs, suggesting that the stimuli did not have additive effects. These findings show that the detection and processing of visceral inputs by NTS neurons can be altered in accordance with the direction of ongoing movements. PMID:21832211

Sugiyama, Yoichiro; Suzuki, Takeshi; DeStefino, Vincent J; Yates, Bill J

2011-08-10

25

Integrative responses of neurons in nucleus tractus solitarius to visceral afferent stimulation and vestibular stimulation in vertical planes.  

UK PubMed Central (United Kingdom)

Anatomical studies have demonstrated that the vestibular nuclei project to nucleus tractus solitarius (NTS), but little is known about the effects of vestibular inputs on NTS neuronal activity. Furthermore, lesions of NTS abolish vomiting elicited by a variety of different triggering mechanisms, including vestibular stimulation, suggesting that emetic inputs may converge on the same NTS neurons. As such, an emetic stimulus that activates gastrointestinal (GI) receptors could alter the responses of NTS neurons to vestibular inputs. In the present study, we examined in decerebrate cats the responses of NTS neurons to rotations of the body in vertical planes before and after the intragastric administration of the emetic compound copper sulfate. The activity of more than one-third of NTS neurons was modulated by vertical vestibular stimulation, with most of the responsive cells having their firing rate altered by rotations in the head-up or head-down directions. These responses were aligned with head position in space, as opposed to the velocity of head movements. The activity of NTS neurons with baroreceptor, pulmonary, and GI inputs could be modulated by vertical plane rotations. However, injection of copper sulfate into the stomach did not alter the responses to vestibular stimulation of NTS neurons that received GI inputs, suggesting that the stimuli did not have additive effects. These findings show that the detection and processing of visceral inputs by NTS neurons can be altered in accordance with the direction of ongoing movements.

Sugiyama Y; Suzuki T; DeStefino VJ; Yates BJ

2011-11-01

26

Effects of body to head rotation on the labyrinthine responses of rat vestibular neurons.  

Science.gov (United States)

Vestibulospinal reflexes elicited by head displacement in space depend on the direction of body displacement, because the neuronal responses to labyrinthine stimulation are tuned by neck displacement: a directional tuning takes place in the medial cerebellum and in spinal motoneurons, while a gain and a basal activity tuning can be observed in the reticular formation, a target structure of the medial cerebellum. In the present study, we investigated whether also the response of vestibular nuclear neurons (another target of the medial cerebellum) to labyrinthine stimulation is tuned by neck displacement and which parameters of the response are modulated by it. In urethane-anaesthetized Wistar rats, single-unit activity was recorded from the vestibular nuclei at rest and during wobble of the whole animal at 0.156 Hz. This stimulus tilted the animal's head by a constant amplitude (5°), in a direction rotating at a constant velocity over the horizontal plane, either in clockwise or counter clockwise direction. The gain and the direction of neuronal responses to wobble were evaluated through Fourier analysis, in the control position (with coincident head and body axes) and following a body-to-head rotation of 5-30° over the horizontal plane, in both directions. Most of the vestibular neurons modified their response gain and/or their basal activity following body-to-head rotation, as it occurs in the reticular formation. Only few neurons modified their response direction, as occurs in the cerebellum and in spinal motoneurons. The different behaviour of cerebellar neurons and of their vestibular and reticular target cells, suggests that the role played by the cerebellum in the neck tuning of vestibulospinal reflexes has to be reconsidered. PMID:23587843

Barresi, M; Grasso, C; Li Volsi, G; Manzoni, D

2013-04-13

27

Effects of body to head rotation on the labyrinthine responses of rat vestibular neurons.  

UK PubMed Central (United Kingdom)

Vestibulospinal reflexes elicited by head displacement in space depend on the direction of body displacement, because the neuronal responses to labyrinthine stimulation are tuned by neck displacement: a directional tuning takes place in the medial cerebellum and in spinal motoneurons, while a gain and a basal activity tuning can be observed in the reticular formation, a target structure of the medial cerebellum. In the present study, we investigated whether also the response of vestibular nuclear neurons (another target of the medial cerebellum) to labyrinthine stimulation is tuned by neck displacement and which parameters of the response are modulated by it. In urethane-anaesthetized Wistar rats, single-unit activity was recorded from the vestibular nuclei at rest and during wobble of the whole animal at 0.156 Hz. This stimulus tilted the animal's head by a constant amplitude (5°), in a direction rotating at a constant velocity over the horizontal plane, either in clockwise or counter clockwise direction. The gain and the direction of neuronal responses to wobble were evaluated through Fourier analysis, in the control position (with coincident head and body axes) and following a body-to-head rotation of 5-30° over the horizontal plane, in both directions. Most of the vestibular neurons modified their response gain and/or their basal activity following body-to-head rotation, as it occurs in the reticular formation. Only few neurons modified their response direction, as occurs in the cerebellum and in spinal motoneurons. The different behaviour of cerebellar neurons and of their vestibular and reticular target cells, suggests that the role played by the cerebellum in the neck tuning of vestibulospinal reflexes has to be reconsidered.

Barresi M; Grasso C; Li Volsi G; Manzoni D

2013-08-01

28

Retrograde transport of (/sup 3/H)-D-aspartate label by cochlear and vestibular efferent neurons  

Energy Technology Data Exchange (ETDEWEB)

(/sup 3/H)-D-aspartic acid was injected into the inner ear of rats. After a six hour survival time, labeled cells were found at all locations known to contain efferent cochlear or vestibular neurons. Most labeled neurons were found in the ipsilateral lateral superior olivary nucleus (LSO), although both ventral nuclei of the trapezoid body (VTB), group E, and the caudal pontine reticular nucleus (CPR) just adjacent to the ascending limb of the facial nerve also contained labeled cells. Because not all efferent neurons in the rat could be previously shown to be cholinergic, aspartate and glutamate are efferent transmitter candidates.

Schwarz, D.W.; Schwarz, I.E.

1988-01-01

29

Retrograde transport of [3H]-D-aspartate label by cochlear and vestibular efferent neurons  

International Nuclear Information System (INIS)

[3H]-D-aspartic acid was injected into the inner ear of rats. After a six hour survival time, labeled cells were found at all locations known to contain efferent cochlear or vestibular neurons. Most labeled neurons were found in the ipsilateral lateral superior olivary nucleus (LSO), although both ventral nuclei of the trapezoid body (VTB), group E, and the caudal pontine reticular nucleus (CPR) just adjacent to the ascending limb of the facial nerve also contained labeled cells. Because not all efferent neurons in the rat could be previously shown to be cholinergic, aspartate and glutamate are efferent transmitter candidates.

1988-01-01

30

Rhythmic activity of neurons in the rostral ventrolateral medulla of conscious cats: effect of removal of vestibular inputs.  

Science.gov (United States)

Although it is well established that bulbospinal neurons located in the rostral ventrolateral medulla (RVLM) play a pivotal role in regulating sympathetic nerve activity and blood pressure, virtually all neurophysiological studies of this region have been conducted in anesthetized or decerebrate animals. In the present study, we used time- and frequency-domain analyses to characterize the naturally occurring discharges of RVLM neurons in conscious cats. Specifically, we compared their activity to fluctuations in carotid artery blood flow to identify neurons with cardiac-related (CR) activity; we then considered whether neurons with CR activity also had a higher-frequency rhythmic firing pattern. In addition, we ascertained whether the surgical removal of vestibular inputs altered the rhythmic discharge properties of RVLM neurons. Less than 10% of RVLM neurons expressed CR activity, although the likelihood of observing a neuron with CR activity in the RVLM varied between recording sessions, even when tracking occurred in a very limited area and was higher after vestibular inputs were surgically removed. Either a 10-Hz or a 20- to 30-Hz rhythmic discharge pattern coexisted with the CR discharges in some of the RVLM neurons. Additionally, the firing rate of RVLM neurons, including those with CR activity, decreased after vestibular lesions. These findings raise the prospect that RVLM neurons may or may not express rhythmic firing patterns at a particular time due to a variety of influences, including descending projections from higher brain centers and sensory inputs, such as those from the vestibular system. PMID:21734018

Barman, Susan M; Sugiyama, Yoichiro; Suzuki, Takeshi; Cotter, Lucy A; DeStefino, Vincent J; Reighard, Derek A; Cass, Stephen P; Yates, Bill J

2011-07-06

31

Rhythmic activity of neurons in the rostral ventrolateral medulla of conscious cats: effect of removal of vestibular inputs.  

UK PubMed Central (United Kingdom)

Although it is well established that bulbospinal neurons located in the rostral ventrolateral medulla (RVLM) play a pivotal role in regulating sympathetic nerve activity and blood pressure, virtually all neurophysiological studies of this region have been conducted in anesthetized or decerebrate animals. In the present study, we used time- and frequency-domain analyses to characterize the naturally occurring discharges of RVLM neurons in conscious cats. Specifically, we compared their activity to fluctuations in carotid artery blood flow to identify neurons with cardiac-related (CR) activity; we then considered whether neurons with CR activity also had a higher-frequency rhythmic firing pattern. In addition, we ascertained whether the surgical removal of vestibular inputs altered the rhythmic discharge properties of RVLM neurons. Less than 10% of RVLM neurons expressed CR activity, although the likelihood of observing a neuron with CR activity in the RVLM varied between recording sessions, even when tracking occurred in a very limited area and was higher after vestibular inputs were surgically removed. Either a 10-Hz or a 20- to 30-Hz rhythmic discharge pattern coexisted with the CR discharges in some of the RVLM neurons. Additionally, the firing rate of RVLM neurons, including those with CR activity, decreased after vestibular lesions. These findings raise the prospect that RVLM neurons may or may not express rhythmic firing patterns at a particular time due to a variety of influences, including descending projections from higher brain centers and sensory inputs, such as those from the vestibular system.

Barman SM; Sugiyama Y; Suzuki T; Cotter LA; DeStefino VJ; Reighard DA; Cass SP; Yates BJ

2011-10-01

32

Fos expression in neurons of the rat vestibulo-autonomic pathway activated by sinusoidal galvanic vestibular stimulation.  

UK PubMed Central (United Kingdom)

The vestibular system sends projections to brainstem autonomic nuclei that modulate heart rate and blood pressure in response to changes in head and body position with regard to gravity. Consistent with this, binaural sinusoidally modulated galvanic vestibular stimulation (sGVS) in humans causes vasoconstriction in the legs, while low frequency (0.02-0.04?Hz) sGVS causes a rapid drop in heart rate and blood pressure in anesthetized rats. We have hypothesized that these responses occur through activation of vestibulo-sympathetic pathways. In the present study, c-Fos protein expression was examined in neurons of the vestibular nuclei and rostral ventrolateral medullary region (RVLM) that were activated by low frequency sGVS. We found c-Fos-labeled neurons in the spinal, medial, and superior vestibular nuclei (SpVN, MVN, and SVN, respectively) and the parasolitary nucleus. The highest density of c-Fos-positive vestibular nuclear neurons was observed in MVN, where immunolabeled cells were present throughout the rostro-caudal extent of the nucleus. c-Fos expression was concentrated in the parvocellular region and largely absent from magnocellular MVN. c-Fos-labeled cells were scattered throughout caudal SpVN, and the immunostained neurons in SVN were restricted to a discrete wedge-shaped area immediately lateral to the IVth ventricle. Immunofluorescence localization of c-Fos and glutamate revealed that approximately one third of the c-Fos-labeled vestibular neurons showed intense glutamate-like immunofluorescence, far in excess of the stain reflecting the metabolic pool of cytoplasmic glutamate. In the RVLM, which receives a direct projection from the vestibular nuclei and sends efferents to preganglionic sympathetic neurons in the spinal cord, we observed an approximately threefold increase in c-Fos labeling in the sGVS-activated rats. We conclude that localization of c-Fos protein following sGVS is a reliable marker for sGVS-activated neurons of the vestibulo-sympathetic pathway.

Holstein GR; Friedrich VL Jr; Martinelli GP; Ogorodnikov D; Yakushin SB; Cohen B

2012-01-01

33

Characteristics of laser stimulation by near infrared pulses of retinal and vestibular primary neurons.  

UK PubMed Central (United Kingdom)

BACKGROUND AND OBJECTIVE: The optical stimulation of neurons from pulsed infrared lasers has appeared over the last years as an alternative to classical electric stimulations based on conventional electrodes. Laser stimulation could provide a better spatial selectivity allowing single-cell stimulation without prerequisite contact. In this work we present relevant physical characteristics of a non-lethal stimulation of cultured mouse vestibular and retinal ganglion neurons by single infrared laser pulses. STUDY DESIGN/MATERIALS AND METHODS: Vestibular and retinal ganglion neurons were stimulated by a 100-400 mW pulsed laser diode beam (wavelengths at 1,470, 1,535, 1,875 nm) launched into a multimode optical fiber positioned at a few hundred micrometers away from the neurons. Ionic exchange measurements at the neuron membrane were achieved by whole-cell patch-clamp recordings. Stimulation and damage thresholds, duration and repetition rate of stimulation and temperature were investigated. RESULTS: All three lasers induced safe and reproducible action potentials (APs) on both types of neurons. The radiant exposure thresholds required to elicit APs range from 15 ± 5 to 100 ± 5 J cm(-2) depending on the laser power and on the pulse duration. The damage thresholds, observed by a vital dye, were significantly greater than the stimulation thresholds. In the pulse duration range of our study (2-30 milliseconds), similar effects were observed for the three lasers. Measurements of the local temperature of the neuron area show that radiant exposures required for reliable stimulations at various pulse durations or laser powers correspond to a temperature increase from 22 °C (room temperature) to 55-60 °C. Stimulations by laser pulses at repetition rate of 1, 2, and 10 Hz during 10 minutes confirmed that the neurons were not damaged and were able to survive such temperatures. CONCLUSION: These results show that infrared laser radiations provide a possible way to safely stimulate retinal and vestibular ganglion neurons. A similar temperature threshold is required to trigger neurons independently of variable energy thresholds, suggesting that an absolute temperature is required.

Bec JM; Albert ES; Marc I; Desmadryl G; Travo C; Muller A; Chabbert C; Bardin F; Dumas M

2012-11-01

34

Identity, expression and functional role of the sodium-activated potassium current in vestibular ganglion afferent neurons.  

UK PubMed Central (United Kingdom)

Vestibular afferent neurons (VANs) transmit information from the vestibular end organs to the central nuclei. This information is encoded within the firing pattern of these cells and is heavily influenced by the K? conductances expressed by vestibular neurons. In the present study, we describe the presence of a previously unidentified Na?-activated K? conductance (KNa) in these cells. We observed that the blocking of Na? channels by tetrodotoxin (TTX) or the substitution of choline for Na? in the extracellular solution during voltage clamp pulses resulted in the reduction of a sustained outward current that was dependent on the Na? current. Furthermore, increases in the intracellular concentration of Na? that were made by blocking the Na?/K? ATPase with ouabain increased the amplitude of the outward current, and reduction of the intracellular Cl? concentration reduced the TTX-sensitive outward current. The substitution of Li? for Na? in the extracellular solution significantly reduced the amplitude of the outward current in voltage clamp pulses and decreased the afterhyperpolarization (AHP) of the action potentials in current clamp experiments. These electrophysiological results are consistent with the presence of mRNA transcripts for the KNa subunits Slick and Slack in the vestibular ganglia and in the sensory epithelium, which were detected using reverse-transcription polymerase chain reaction (RT-PCR). These results are also consistent with the immunolabeling of Slick and Slack protein in isolated vestibular neurons, in the vestibular ganglion and in the vestibular sensory epithelium. These results indicate that KNa channels are expressed in VANs and in their terminals. Furthermore, these data indicate that these channels may contribute to the firing pattern of vestibular neurons.

Cervantes B; Vega R; Limón A; Soto E

2013-06-01

35

Postsynaptic mechanisms underlying the excitatory action of histamine on medial vestibular nucleus neurons in rats.  

UK PubMed Central (United Kingdom)

BACKGROUND AND PURPOSE: Anti-histaminergic drugs have been widely used in the clinical treatment of vestibular disorders and most studies concentrate on their presynaptic actions. The present study investigated the postsynaptic effect of histamine on medial vestibular nucleus (MVN) neurons and the underlying mechanisms. EXPERIMENTAL APPROACH: Histamine-induced postsynaptic actions on MVN neurons and the corresponding receptor and ionic mechanisms were detected by whole-cell patch-clamp recordings on rat brain slices. The distribution of postsynaptic histamine H1 , H2 and H4 receptors was mapped by double and single immunostaining. Furthermore, the expression of mRNAs for H1 , H2 and H4 receptors and for subtypes of Na(+) -Ca(2+) exchangers (NCXs) and hyperpolarization-activated cyclic nucleotide-gated (HCN) channels was assessed by quantitative real-time RT-PCR. KEY RESULTS: A marked postsynaptic excitatory effect, co-mediated by histamine H1 and H2 receptors, was involved in the histamine-induced depolarization of MVN neurons. Postsynaptic H1 and H2 rather than H4 receptors were co-localized in the same MVN neurons. NCXs contributed to the inward current mediated by H1 receptors, whereas HCN channels were responsible for excitation induced by activation of H2 receptors. Moreover, NCX1 and NCX3 rather than NCX2, and HCN1 rather than HCN2-4 mRNAs, were abundantly expressed in MVN. CONCLUSION AND IMPLICATIONS: NCXs coupled to H1 receptors and HCN channels linked to H2 receptors co-mediate the strong postsynaptic excitatory action of histamine on MVN neurons. These results highlight an active role of postsynaptic mechanisms in the modulation by central histaminergic systems of vestibular functions and suggest potential targets for clinical treatment of vestibular disorders. LINKED ARTICLES: This article is part of a themed issue on Histamine Pharmacology Update. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2013.170.issue-1.

Zhang XY; Yu L; Zhuang QX; Peng SY; Zhu JN; Wang JJ

2013-09-01

36

Downbeat nystagmus associated with damage to the medial longitudinal fasciculus of the pons: a vestibular balance control mechanism via the lower brainstem paramedian tract neurons.  

UK PubMed Central (United Kingdom)

The paramedian tract (PMT) neurons, a group of neurons associated with eye movement that project into the cerebellar flocculus, are present in or near the medial longitudinal fasciculus (MLF) in the paramedian region of the lower brainstem. A 66-year-old man with multiple sclerosis in whom downbeat nystagmus appeared along with right MLF syndrome due to a unilateral pontomedullary lesion is described. In light of these findings, a possible schema for the vestibular balance control mechanism circuit of the PMT neurons via the flocculus is presented. Damage to the PMT neurons impaired the elective inhibitory control mechanism of the anterior semicircular canal neural pathway by the flocculus. This resulted in the appearance of anterior semicircular canal-dominant vestibular imbalance and the formation of downbeat nystagmus. From the pathogenesis of this vertical vestibular nystagmus, the action of the PMT neurons in the vestibular eye movement neuronal pathway to maintain vestibular balance was conjectured to be as follows. PMT neurons transmit vestibular information from the anterior semicircular canals to the cerebellum, forming a cerebellum/brainstem feedback loop. Vestibular information from that loop is integrated in the cerebellum, inhibiting only the anterior semicircular canal neuronal pathway via the flocculus and controlling vestibular balance.

Nakamagoe K; Fujizuka N; Koganezawa T; Yamaguchi T; Tamaoka A

2013-05-01

37

Effects of galvanic vestibular stimulation on postural limb reflexes and neurons of spinal postural network.  

UK PubMed Central (United Kingdom)

Quadrupeds maintain the dorsal side up body orientation due to the activity of the postural control system driven by limb mechanoreceptors. Binaural galvanic vestibular stimulation (GVS) causes a lateral body sway toward the anode. Previously, we have shown that this new position is actively stabilized, suggesting that GVS changes a set point in the reflex mechanisms controlling body posture. The aim of the present study was to reveal the underlying neuronal mechanisms. Experiments were performed on decerebrate rabbits. The vertebral column was rigidly fixed, whereas hindlimbs were positioned on a platform. Periodic lateral tilts of the platform caused postural limb reflexes (PLRs): activation of extensors in the loaded and flexing limb and a decrease in extensor activity in the opposite (unloaded and extending) limb. Putative spinal interneurons were recorded in segments L4-L5 during PLRs, with and without GVS. We have found that GVS enhanced PLRs on the cathode side and reduced them on the anode side. This asymmetry in PLRs can account for changes in the stabilized body orientation observed in normal rabbits subjected to continuous GVS. Responses to platform tilts (frequency modulation) were observed in 106 spinal neurons, suggesting that they can contribute to PLR generation. Two neuron groups were active in opposite phases of the tilt cycle of the ipsi-limb: F-neurons in the flexion phase, and E-neurons in the extension phase. Neurons were driven mainly by afferent input from the ipsi-limb. If one supposes that F- and E-neurons contribute, respectively, to excitation and inhibition of extensor motoneurons, one can expect that the pattern of response to GVS in F-neurons will be similar to that in extensor muscles, whereas E-neurons will have an opposite pattern. We have found that ~40% of all modulated neurons meet this condition, suggesting that they contribute to the generation of PLRs and to the GVS-caused changes in PLRs.

Hsu LJ; Zelenin PV; Orlovsky GN; Deliagina TG

2012-07-01

38

Effects of galvanic vestibular stimulation on postural limb reflexes and neurons of spinal postural network.  

Science.gov (United States)

Quadrupeds maintain the dorsal side up body orientation due to the activity of the postural control system driven by limb mechanoreceptors. Binaural galvanic vestibular stimulation (GVS) causes a lateral body sway toward the anode. Previously, we have shown that this new position is actively stabilized, suggesting that GVS changes a set point in the reflex mechanisms controlling body posture. The aim of the present study was to reveal the underlying neuronal mechanisms. Experiments were performed on decerebrate rabbits. The vertebral column was rigidly fixed, whereas hindlimbs were positioned on a platform. Periodic lateral tilts of the platform caused postural limb reflexes (PLRs): activation of extensors in the loaded and flexing limb and a decrease in extensor activity in the opposite (unloaded and extending) limb. Putative spinal interneurons were recorded in segments L4-L5 during PLRs, with and without GVS. We have found that GVS enhanced PLRs on the cathode side and reduced them on the anode side. This asymmetry in PLRs can account for changes in the stabilized body orientation observed in normal rabbits subjected to continuous GVS. Responses to platform tilts (frequency modulation) were observed in 106 spinal neurons, suggesting that they can contribute to PLR generation. Two neuron groups were active in opposite phases of the tilt cycle of the ipsi-limb: F-neurons in the flexion phase, and E-neurons in the extension phase. Neurons were driven mainly by afferent input from the ipsi-limb. If one supposes that F- and E-neurons contribute, respectively, to excitation and inhibition of extensor motoneurons, one can expect that the pattern of response to GVS in F-neurons will be similar to that in extensor muscles, whereas E-neurons will have an opposite pattern. We have found that ~40% of all modulated neurons meet this condition, suggesting that they contribute to the generation of PLRs and to the GVS-caused changes in PLRs. PMID:22514291

Hsu, L-J; Zelenin, P V; Orlovsky, G N; Deliagina, T G

2012-04-18

39

Histamine excites neurons of the inferior vestibular nucleus in rats by activation of H1 and H2 receptors.  

UK PubMed Central (United Kingdom)

By using brain slice preparations and extracellular recordings, the effect of histamine on spontaneous firing activities of neurons in the inferior vestibular nucleus (IVN), a key structure responsible for integration of vestibular, multisensory, and cerebellar inputs, in rats was investigated. Perfusing slices with histamine (1-10?M) elicited an excitatory response on IVN neurons. The responses were not blocked by low Ca(2+)/high Mg(2+) medium, indicating a direct postsynaptic effect of the amine. Furthermore, the histamine-induced excitation was partially blocked by selective histamine H1 receptor antagonist mepyramine (1?M) and H2 receptor antagonist ranitidine (1?M), respectively. Co-application of mepyramine and ranitidine nearly totally antagonized the histamine-induced excitation. Additionally, both selective H1 receptor agonist 2-pyridylethylamine (30-300?M) and H2 receptor agonist dimaprit (10-100?M) effectively mimicked the excitatory action of histamine on IVN neurons. Moreover, selective H4 antagonist JNJ7777120 (10?M) and agonist VUF8430 (30-300?M) had no effect on IVN neurons. These results demonstrate that histamine excites IVN neurons via postsynaptic H1 and H2 rather than H4 receptors, and suggest that the central histaminergic system actively modulate all four major vestibular nuclei including the IVN and may subsequently influence the vestibular nuclei-related reflexes and functions.

Peng SY; Zhuang QX; He YC; Zhu JN; Wang JJ

2013-04-01

40

Activation of immobility-related hippocampal theta by cholinergic septohippocampal neurons during vestibular stimulation.  

Science.gov (United States)

The vestibular system has been suggested to participate in spatial navigation, a function ascribed to the hippocampus. Vestibular stimulation during spatial navigation activates a hippocampal theta rhythm (4-10 Hz), which may enhance spatial processing and motor response. We hypothesize that a cholinergic, atropine-sensitive theta is generated during passive whole-body rotation in freely behaving rats. Hippocampal EEGs were recorded by implanted electrodes in CA1 while rats were rotated on a vertical axis, for a minute or longer, at different angular velocities. Rotation induced a continuous hippocampal theta rhythm while the rat was immobile, in both light and dark conditions. Theta peak frequency showed a significant increase during high (50-70 rpm) as compared with a lower (20-49 rpm) rotational velocity. Rotation-induced theta was abolished by muscarinic receptor antagonist atropine sulfate (50 mg/kg i.p.) but not by atropine methyl nitrate (50 mg/kg i.p.), which did not pass the blood-brain barrier. Theta was attenuated in rats in which cholinergic neurons in the medial septum (MS) were lesioned with 192 IgG-saporin (0.14 ?g in 0.4 ?l), as confirmed by depletion of MS cells immunoreactive to choline acetyltransferase and an absence of acetylcholinesterase staining in the hippocampus. Bilateral lesion of the vestibular receptors by sodium arsanilate (30 mg in 0.1 ml, intratympanically) also attenuated the rotation-induced theta rhythm. In intact rats, field excitatory postsynaptic potentials (fEPSPs) in CA1 evoked by commissural stimulation were smaller during walking or rotation as compared with during immobility. Modulation of fEPSP was absent following atropine sulfate in intact rats and in 192 IgG-saporin lesion rats. In summary, this is the first report of a continuous atropine-sensitive hippocampal theta in the rat induced by vestibular stimulation during rotation, and accompanied by cholinergic modulation of hippocampal synaptic transmission. Vestibular-activated septohippocampal cholinergic activity could be an important component in sensorimotor processing and spatial memory. PMID:21542057

Tai, Siew Kian; Ma, Jingyi; Ossenkopp, Klaus-Peter; Leung, L Stan

2011-05-03

 
 
 
 
41

Activation of immobility-related hippocampal theta by cholinergic septohippocampal neurons during vestibular stimulation.  

UK PubMed Central (United Kingdom)

The vestibular system has been suggested to participate in spatial navigation, a function ascribed to the hippocampus. Vestibular stimulation during spatial navigation activates a hippocampal theta rhythm (4-10 Hz), which may enhance spatial processing and motor response. We hypothesize that a cholinergic, atropine-sensitive theta is generated during passive whole-body rotation in freely behaving rats. Hippocampal EEGs were recorded by implanted electrodes in CA1 while rats were rotated on a vertical axis, for a minute or longer, at different angular velocities. Rotation induced a continuous hippocampal theta rhythm while the rat was immobile, in both light and dark conditions. Theta peak frequency showed a significant increase during high (50-70 rpm) as compared with a lower (20-49 rpm) rotational velocity. Rotation-induced theta was abolished by muscarinic receptor antagonist atropine sulfate (50 mg/kg i.p.) but not by atropine methyl nitrate (50 mg/kg i.p.), which did not pass the blood-brain barrier. Theta was attenuated in rats in which cholinergic neurons in the medial septum (MS) were lesioned with 192 IgG-saporin (0.14 ?g in 0.4 ?l), as confirmed by depletion of MS cells immunoreactive to choline acetyltransferase and an absence of acetylcholinesterase staining in the hippocampus. Bilateral lesion of the vestibular receptors by sodium arsanilate (30 mg in 0.1 ml, intratympanically) also attenuated the rotation-induced theta rhythm. In intact rats, field excitatory postsynaptic potentials (fEPSPs) in CA1 evoked by commissural stimulation were smaller during walking or rotation as compared with during immobility. Modulation of fEPSP was absent following atropine sulfate in intact rats and in 192 IgG-saporin lesion rats. In summary, this is the first report of a continuous atropine-sensitive hippocampal theta in the rat induced by vestibular stimulation during rotation, and accompanied by cholinergic modulation of hippocampal synaptic transmission. Vestibular-activated septohippocampal cholinergic activity could be an important component in sensorimotor processing and spatial memory.

Tai SK; Ma J; Ossenkopp KP; Leung LS

2012-04-01

42

Neuronal classification and marker gene identification via single-cell expression profiling of brainstem vestibular neurons subserving cerebellar learning.  

UK PubMed Central (United Kingdom)

Identification of marker genes expressed in specific cell types is essential for the genetic dissection of neural circuits. Here we report a new strategy for classifying heterogeneous populations of neurons into functionally distinct types and for identifying associated marker genes. Quantitative single-cell expression profiling of genes related to neurotransmitters and ion channels enables functional classification of neurons; transcript profiles for marker gene candidates identify molecular handles for manipulating each cell type. We apply this strategy to the mouse medial vestibular nucleus (MVN), which comprises several types of neurons subserving cerebellar-dependent learning in the vestibulo-ocular reflex. Ion channel gene expression differed both qualitatively and quantitatively across cell types and could distinguish subtle differences in intrinsic electrophysiology. Single-cell transcript profiling of MVN neurons established six functionally distinct cell types and associated marker genes. This strategy is applicable throughout the nervous system and could facilitate the use of molecular genetic tools to examine the behavioral roles of distinct neuronal populations.

Kodama T; Guerrero S; Shin M; Moghadam S; Faulstich M; du Lac S

2012-06-01

43

Integrative responses of neurons in parabrachial nuclei to a nauseogenic gastrointestinal stimulus and vestibular stimulation in vertical planes.  

UK PubMed Central (United Kingdom)

The parabrachial and adjacent Kölliker-Fuse (PBN/KF) nuclei play a key role in relaying visceral afferent inputs to the hypothalamus and limbic system and are, thus, believed to participate in generating nausea and affective responses elicited by gastrointestinal (GI) signals. In addition, the PBN/KF region receives inputs from the vestibular system and likely mediates the malaise associated with motion sickness. However, previous studies have not considered whether GI and vestibular inputs converge on the same PBN/KF neurons, and if so, whether the GI signals alter the responses of the cells to body motion. The present study, conducted in decerebrate cats, tested the hypothesis that intragastric injection of copper sulfate, which elicits emesis by irritating the stomach lining, modifies the sensitivity of PBN/KF neurons to vertical plane rotations that activate vestibular receptors. Intragastric copper sulfate produced a 70% median change in the gain of responses to vertical plane rotations of PBN/KF units, whose firing rate was modified by the administration of the compound; the response gains for 16 units increased and those for 17 units decreased. The effects were often dramatic: out of 51 neurons tested, 13 responded to the rotations only after copper sulfate was injected, whereas 10 others responded only before drug delivery. These data show that a subset of PBN/KF neurons, whose activity is altered by a nauseogenic stimulus also respond to body motion and that irritation of the stomach lining can either cause an amplification or reduction in the sensitivity of the units to vestibular inputs. The findings imply that nausea and affective responses to vestibular stimuli may be modified by the presence of emetic signals from the GI system.

Suzuki T; Sugiyama Y; Yates BJ

2012-04-01

44

Integrative responses of neurons in parabrachial nuclei to a nauseogenic gastrointestinal stimulus and vestibular stimulation in vertical planes.  

Science.gov (United States)

The parabrachial and adjacent Kölliker-Fuse (PBN/KF) nuclei play a key role in relaying visceral afferent inputs to the hypothalamus and limbic system and are, thus, believed to participate in generating nausea and affective responses elicited by gastrointestinal (GI) signals. In addition, the PBN/KF region receives inputs from the vestibular system and likely mediates the malaise associated with motion sickness. However, previous studies have not considered whether GI and vestibular inputs converge on the same PBN/KF neurons, and if so, whether the GI signals alter the responses of the cells to body motion. The present study, conducted in decerebrate cats, tested the hypothesis that intragastric injection of copper sulfate, which elicits emesis by irritating the stomach lining, modifies the sensitivity of PBN/KF neurons to vertical plane rotations that activate vestibular receptors. Intragastric copper sulfate produced a 70% median change in the gain of responses to vertical plane rotations of PBN/KF units, whose firing rate was modified by the administration of the compound; the response gains for 16 units increased and those for 17 units decreased. The effects were often dramatic: out of 51 neurons tested, 13 responded to the rotations only after copper sulfate was injected, whereas 10 others responded only before drug delivery. These data show that a subset of PBN/KF neurons, whose activity is altered by a nauseogenic stimulus also respond to body motion and that irritation of the stomach lining can either cause an amplification or reduction in the sensitivity of the units to vestibular inputs. The findings imply that nausea and affective responses to vestibular stimuli may be modified by the presence of emetic signals from the GI system. PMID:22277934

Suzuki, Takeshi; Sugiyama, Yoichiro; Yates, Bill J

2012-01-25

45

Central compensation of vestibular deficits. II. Influences of roll tilt on different-size lateral vestibular neurons after ipsilateral labyrinth deafferentation.  

UK PubMed Central (United Kingdom)

The activity of 168 Deiters' neurons projecting to lumbosacral segments of the spinal cord has been recorded in precollicular decerebrate cats after ipsilateral acute (aVN) or chronic vestibular neurectomy (cVN), and their response characteristics to sinusoidal stimulation of contralateral labyrinth receptors at the standard parameters (roll tilt at 0.026 Hz, 10 degrees peak displacement) have been related to cell size inferred from the conduction velocity of the corresponding axons. These findings were compared with those elicited in decerebrate cats with both vestibular nerves intact. In all experimental conditions, the higher the coefficient of variation (CV) of the vestibulospinal neurons, reflecting a more irregular unit discharge, the lower was the mean discharge rate at rest. However, the proportion of regularly discharging units (with the lowest CV) decreased after aVN but increased after cVN. The relation found in control experiments, i.e., the faster the conduction velocity of vestibulospinal axon the lower was the unit discharge at rest, was lost after aVN due to a decrease in resting discharge rate of the slow neurons. The mean discharge rate of these units, however, recovered after cVN, so that the negative correlation between resting discharge rate and axonal conduction velocity was reestablished. After aVN, the decrease in resting discharge rate of the slow vestibulospinal neurons was not associated with significant changes in gain (impulses per second per degree) of the unit responses to standard parameters of tilt, so that the sensitivity of these units (percentage change of the mean discharge rate per degree) increased; on the other hand, the resting discharge rate of the fast neurons, which remained almost unchanged after aVN, was associated with a significant increase in gain, thus leading to an average increase in response sensitivity of these units.(ABSTRACT TRUNCATED AT 400 WORDS)

Pompeiano O; Xerri C; Gianni S; Manzoni D

1984-07-01

46

Histamine excites rat superior vestibular nuclear neurons via postsynaptic H1 and H2 receptors in vitro.  

UK PubMed Central (United Kingdom)

The superior vestibular nucleus (SVN), which holds a key position in vestibulo-ocular reflexes and nystagmus, receives direct hypothalamic histaminergic innervations. By using rat brainstem slice preparations and extracellular unitary recordings, we investigated the effect of histamine on SVN neurons and the underlying receptor mechanisms. Bath application of histamine evoked an excitatory response of the SVN neurons, which was not blocked by the low-Ca(2+)/high-Mg(2+) medium, indicating a direct postsynaptic effect of the amine. Selective histamine H1 receptor agonist 2-pyridylethylamine and H2 receptor agonist dimaprit, rather than VUF8430, a selective H4 receptor agonist, mimicked the excitation of histamine on SVN neurons. In addition, selective H1 receptor antagonist mepyramine and H2 receptor antagonist ranitidine, but not JNJ7777120, a selective H4 receptor antagonist, partially blocked the excitatory response of SVN neurons to histamine. Moreover, mepyramine together with ranitidine nearly totally blocked the histamine-induced excitation. Immunostainings further showed that histamine H1 and H2 instead of H4 receptors existed in the SVN. These results demonstrate that histamine excites the SVN neurons via postsynaptic histamine H1 and H2 receptors, and suggest that the central histaminergic innervation from the hypothalamus may actively bias the SVN neuronal activity and subsequently modulate the SVN-mediated vestibular functions and gaze control.

Zhuang QX; Wu YH; Wu GY; Zhu JN; Wang JJ

2013-01-01

47

Chondroitin sulfates in the developing rat hindbrain confine commissural projections of vestibular nuclear neurons.  

UK PubMed Central (United Kingdom)

BACKGROUND: Establishing correct neuronal circuitry is crucial to proper function of the vertebrate nervous system. The abundance of chondroitin sulfate (CS) proteoglycans in embryonic neural environments suggests that matrix proteoglycans regulate axonal projections when fiber tracts have not yet formed. Among the early-born neurons, the vestibular nucleus (VN) neurons initiate commissural projections soon after generation at E12.5 and reach the contralateral target by E15.5 in the rat hindbrain. We therefore exploited 24-hour cultures (1 day in vitro (DIV)) of the rat embryos and chondroitinase ABC treatment of the hindbrain matrix to reveal the role of CS moieties in axonal initiation and projection in the early hindbrain. RESULTS: DiI tracing from the VN at E12.5(+1 DIV) showed contralaterally projecting fibers assuming fascicles that hardly reached the midline in the controls. In the enzyme-treated embryos, the majority of fibers were unfasciculated as they crossed the midline at 90°. At E13.5(+1 DIV), the commissural projections formed fascicles and crossed the midline in the controls. Enzyme treatment apparently did not affect the pioneer axons that had advanced as thick fascicles normal to the midline and beyond, towards the contralateral VN. Later projections, however, traversed the enzyme-treated matrix as unfasciculated fibers, deviated from the normal course crossing the midline at various angles and extending beyond the contralateral VN. This suggests that CSs also limit the course of the later projections, which otherwise would be attracted to alternative targets. CONCLUSIONS: CS moieties in the early hindbrain therefore control the course and fasciculation of axonal projections and the timing of axonal arrival at the target.

Kwok JC; Yuen YL; Lau WK; Zhang FX; Fawcett JW; Chan YS; Shum DK

2012-01-01

48

[Examination of dynamic body balance using the body tracking test in cases of vestibular neuronitis].  

Science.gov (United States)

Body Tracking Test (BTT) is a testing method of the dynamic body balance function wherein movement of the center of gravity in accordance with a moving visual target stimulus is examined to evaluate the tracking function of the body. The objects were the patients who were diagnosed as having vestibular neuronitis at the Department of Otolaryngology in Toho University medical center Sakura hospital, and were undergoing hospital treatment. Lateral BTT was performed in 31 subjects, and antero-posterior (A-P) BTT in 45 subjects. Although gaze nystagmus was noted, inspection was enforced when a standing position posture was possible. In lateral BTT, the average (cm/second) horizontal direction body sway speed was compared, however, no clear lateral difference was noted. In the antero-posterior (A-P) BTT, it inquired using the direction body sway average center displacement (cm) of X. Deviation was seen by the affected side in stabilometry. Deviation was seen by the unaffected side in the antero-posterior (A-P) BTT. This phenomenon differs from the deviation pattern until now and is considered to involve participation of the higher centers. PMID:18939406

Yoshida, Tomoe; Yamamoto, Masahiko; Nomura, Toshiyuki; Ohwada, Satoko; Takazawa, Rio; Ikemiyagi, Yoshihiro; Shigeta, Fuyuko

2008-09-01

49

Mechanisms of Sustained High Firing Rates in Two Classes of Vestibular Nucleus Neurons: Differential Contributions of Resurgent Na, Kv3, and BK Currents  

Digital Repository Infrastructure Vision for European Research (DRIVER)

To fire at high rates, neurons express ionic currents that work together to minimize refractory periods by ensuring that sodium channels are available for activation shortly after each action potential. Vestibular nucleus neurons operate around high baseline firing rates and encode information with ...

Gittis, Aryn H.; Moghadam, Setareh H.; du Lac, Sascha

50

[The influence of otolithic afferentation on the vestibulo-ocular interaction in the patients presenting with an unilateral lesion in a peripheral vestibular neuron].  

UK PubMed Central (United Kingdom)

The objective of the present work was to study the influence of otolithic afferentation on the vestibulo-ocular interaction in 20 patients with vestibular neuronitis (at the stages of decompensation and subcompensation) and in 30 healthy subjects by the electronystagmographic technique. The sinusoidal (program 1) and eccentric (program 2) rotation was applied with the angular velocity of 10 degrees/s (stimulus 1, rotation rate 0.04 Hz), 30 degrees/s (stimulus II, rotation rate 0.12 Hz), 60 degrees/s (stimulus III) and oscillation periods of 18, 6, and 3 s respectively. No significant changes in the parameters of the vesicular reflex were observed in the patients with vestibular neuronitis and control subjects studied in the phase of decompensation under programs 1 and 2 . The study of the patients presenting with vestibular neuronitis in the subcompensation phase (program 2) revealed a significant increase of nystagmus intensity on the affected side compared with the respective parameters estimated in the framework of program 1 (p<0.001). The enhancement of stimulation did not result in any significant changes in the character of vestibuloocular interactions. The results of the study indicate that otolithic afferentation influences the process of compensation of peripheral vestibular labyrinth dysfunction in the patients presenting with vestibular neuronitis at the stage of decompensation.

Likhac SA; Pleshko IV

2013-01-01

51

Kv3.3 immunoreactivity in the vestibular nuclear complex of the rat with focus on the medial vestibular nucleus: targeting of Kv3.3 neurones by terminals positive for vesicular glutamate transporter 1.  

UK PubMed Central (United Kingdom)

Kv3 voltage-gated K(+) channels are important in shaping neuronal excitability and are abundant in the CNS, with each Kv3 gene exhibiting a unique expression pattern. Mice lacking the gene encoding for the Kv3.3 subunit exhibit motor deficits. Furthermore, mutations in this gene have been linked to the human disease spinocerebellar ataxia 13, associated with cerebellar and extra-cerebellar symptoms such as imbalance and nystagmus. Kv subunit localisation is important in defining their functional roles and thus, we investigated the distribution of Kv3.3-immunoreactivity in the vestibular nuclear complex of rats with particular focus on the medial vestibular nucleus (MVN). Kv3.3-immunoreactivity was widespread in the vestibular nuclei and was detected in somata, dendrites and synaptic terminals. Kv3.3-immunoreactivity was observed in distinct neuronal populations and dual labelling with the neuronal marker NeuN revealed 28.5+/-1.9% of NeuN labelled MVN neurones were Kv3.3-positive. Kv3.3-immunoreactivity co-localised presynaptically with the synaptic vesicle marker SV2, parvalbumin, the vesicular glutamate transporter VGluT2 and the glycine transporter GlyT2. VGluT1 terminals were scarce within the MVN (2.5+/-1.1 per 50 microm(2)) and co-localisation was not observed. However, 85.4+/-9.4% of VGluT1 terminals targeted and enclosed Kv3.3-immunoreactive somata. Presynaptic Kv3.3 co-localisation with the GABAergic marker GAD67 was also not observed. Cytoplasmic GlyT2 labelling was observed in a subset of Kv3.3-positive neurones. Electron microscopy confirmed a pre- and post-synaptic distribution of the Kv3.3 protein. This study provides evidence supporting a role for Kv3.3 subunits in vestibular processing by regulating neuronal excitability pre- and post-synaptically.

Brooke RE; Corns L; Edwards IJ; Deuchars J

2010-07-01

52

Kv3.3 immunoreactivity in the vestibular nuclear complex of the rat with focus on the medial vestibular nucleus: targeting of Kv3.3 neurones by terminals positive for vesicular glutamate transporter 1.  

Science.gov (United States)

Kv3 voltage-gated K(+) channels are important in shaping neuronal excitability and are abundant in the CNS, with each Kv3 gene exhibiting a unique expression pattern. Mice lacking the gene encoding for the Kv3.3 subunit exhibit motor deficits. Furthermore, mutations in this gene have been linked to the human disease spinocerebellar ataxia 13, associated with cerebellar and extra-cerebellar symptoms such as imbalance and nystagmus. Kv subunit localisation is important in defining their functional roles and thus, we investigated the distribution of Kv3.3-immunoreactivity in the vestibular nuclear complex of rats with particular focus on the medial vestibular nucleus (MVN). Kv3.3-immunoreactivity was widespread in the vestibular nuclei and was detected in somata, dendrites and synaptic terminals. Kv3.3-immunoreactivity was observed in distinct neuronal populations and dual labelling with the neuronal marker NeuN revealed 28.5+/-1.9% of NeuN labelled MVN neurones were Kv3.3-positive. Kv3.3-immunoreactivity co-localised presynaptically with the synaptic vesicle marker SV2, parvalbumin, the vesicular glutamate transporter VGluT2 and the glycine transporter GlyT2. VGluT1 terminals were scarce within the MVN (2.5+/-1.1 per 50 microm(2)) and co-localisation was not observed. However, 85.4+/-9.4% of VGluT1 terminals targeted and enclosed Kv3.3-immunoreactive somata. Presynaptic Kv3.3 co-localisation with the GABAergic marker GAD67 was also not observed. Cytoplasmic GlyT2 labelling was observed in a subset of Kv3.3-positive neurones. Electron microscopy confirmed a pre- and post-synaptic distribution of the Kv3.3 protein. This study provides evidence supporting a role for Kv3.3 subunits in vestibular processing by regulating neuronal excitability pre- and post-synaptically. PMID:20471378

Brooke, Ruth Elizabeth; Corns, Laura; Edwards, Ian James; Deuchars, Jim

2010-05-13

53

Effect of epidural spinal cord stimulation on the activity of lateral vestibular nucleus neurons in the cat.  

UK PubMed Central (United Kingdom)

The activity of neurons in Deiters' lateral vestibular nucleus was recorded in decerebrate cats before, during and after spinal cord stimulation. An almost equal number of units were inhibited and excited early during stimulation. Later during stimulation the majority of units was inhibited. Early after cessation of stimulation an ever larger number of units were inhibited to an even larger extent (for about 2 imp/s on the average). Later after stimulus cessation the predominant inhibitory effect could still be noted, as well as excitation in some units. The results could support the hypothesis that the inhibition of Deiters' neurons during and for some time after epidural cord stimulation may play a part in the decrease of limb spasticity. The mechanism of inhibitory and excitatory unitary responses, side effects during stimulation and differences between the experimental model and human state are discussed.

Culi? M; Jeftinija S

1986-01-01

54

Immunocytochemical study of alpha 1 and beta 2/3 subunits of GABAA receptors in freehand isolated vestibular Deiters' neurons.  

Science.gov (United States)

Vestibular Deiters' neurons have been isolated from bovine brain by the Hydén's freehand dissection technique and challenged with monoclonal antibodies directed toward the alpha 1 and beta 2/3 subunits of the GABAA receptors. Subsequent challenge with fluorescent secondary antibodies and confocal microscopy allowed the study of the cellular distribution of such subunits. In Deiters' neurons the beta 2/3 subunit displayed a clear presence all along the cell body profile and the initial parts of the dendrites. The alpha 1 subunit was found highly present all over the cell interior except the nuclear profiles. The strong presence inside the cells possibly masked its presence on the plasma membrane. However, in part of the cells studied a distinct presence on the plasma membrane was evident. This subunit was visualized also all along the long dendrites of these neurons. The approach we describe here, involving freehand isolated mature neurons from adult animals, may allow a better characterization of the tridimensional distribution of different types of neuronal GABAA receptors in the respect of the approach with brain slices. PMID:12916468

Rapallino, Maria V; Cupello, Aroldo; Luccardini, Camilla; Nieddu, Erica; Seitun, Andrea; Robello, Mauro

2003-01-01

55

Response characteristics of neurons in the cat vestibular nuclei during slow and constant velocity off-vertical axes rotations in the clockwise and counterclockwise rotations  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The responses to slow constant velocity rotations in the clockwise (CW) and counterclockwise (CCW) directions about an axis tilted 10° from the earth's vertical were studied in static tilt-sensitive neurons in the vestibular nuclei of decerebrate cats. Each unit responded to any 360° undirectional r...

Chan, YS; Cheung, YM; Hwang, JC

56

Mechanisms of sustained high firing rates in two classes of vestibular nucleus neurons: differential contributions of resurgent Na, Kv3, and BK currents.  

Science.gov (United States)

To fire at high rates, neurons express ionic currents that work together to minimize refractory periods by ensuring that sodium channels are available for activation shortly after each action potential. Vestibular nucleus neurons operate around high baseline firing rates and encode information with bidirectional modulation of firing rates up to several hundred Hz. To determine the mechanisms that enable these neurons to sustain firing at high rates, ionic currents were measured during firing by using the action potential clamp technique in vestibular nucleus neurons acutely dissociated from transgenic mice. Although neurons from the YFP-16 line fire at rates higher than those from the GIN line, both classes of neurons express Kv3 and BK currents as well as both transient and resurgent Na currents. In the fastest firing neurons, Kv3 currents dominated repolarization at all firing rates and minimized Na channel inactivation by rapidly transitioning Na channels from the open to the closed state. In slower firing neurons, BK currents dominated repolarization at the highest firing rates and sodium channel availability was protected by a resurgent blocking mechanism. Quantitative differences in Kv3 current density across neurons and qualitative differences in immunohistochemically detected expression of Kv3 subunits could account for the difference in firing range within and across cell classes. These results demonstrate how divergent firing properties of two neuronal populations arise through the interplay of at least three ionic currents. PMID:20592126

Gittis, Aryn H; Moghadam, Setareh H; du Lac, Sascha

2010-06-30

57

Mechanisms of sustained high firing rates in two classes of vestibular nucleus neurons: differential contributions of resurgent Na, Kv3, and BK currents.  

UK PubMed Central (United Kingdom)

To fire at high rates, neurons express ionic currents that work together to minimize refractory periods by ensuring that sodium channels are available for activation shortly after each action potential. Vestibular nucleus neurons operate around high baseline firing rates and encode information with bidirectional modulation of firing rates up to several hundred Hz. To determine the mechanisms that enable these neurons to sustain firing at high rates, ionic currents were measured during firing by using the action potential clamp technique in vestibular nucleus neurons acutely dissociated from transgenic mice. Although neurons from the YFP-16 line fire at rates higher than those from the GIN line, both classes of neurons express Kv3 and BK currents as well as both transient and resurgent Na currents. In the fastest firing neurons, Kv3 currents dominated repolarization at all firing rates and minimized Na channel inactivation by rapidly transitioning Na channels from the open to the closed state. In slower firing neurons, BK currents dominated repolarization at the highest firing rates and sodium channel availability was protected by a resurgent blocking mechanism. Quantitative differences in Kv3 current density across neurons and qualitative differences in immunohistochemically detected expression of Kv3 subunits could account for the difference in firing range within and across cell classes. These results demonstrate how divergent firing properties of two neuronal populations arise through the interplay of at least three ionic currents.

Gittis AH; Moghadam SH; du Lac S

2010-09-01

58

GABA and chloride permeate via the same channels across single plasma membranes microdissected from rabbit Deiters' vestibular neurones.  

Science.gov (United States)

The permeation of labelled gamma-aminobutyric acid (GABA) across single microdissected Deiters' membranes has been studied in a microchamber system. The GABA permeation is via pores which are blocked by 4,4'-diisothiocyanato stilbene-2-2'disulphonic acid (DIDS). As this substance blocks as well chloride permeation across these membranes we tested whether GABA and chloride permeate across the same pores. Membrane pre-treatment with different doses of corticotropin releasing factor (CRF), a membrane permeant cyclic AMP analogue and phalloidin parallelly block the permeation of the two substances. Thus, it is most probable that GABA and chloride pass across the same pores. These pores may be swelling activated ones, opened by the mechanical stress on the membranes in the microchamber system. The passage of GABA across these pores may be of physiological importance in the termination of GABA inhibitory action on the vestibular Deiters' neurones. PMID:11683681

Rapallino, M V; Cupello, A

2001-10-01

59

Neuronal coding of linear motion in the vestibular nuclei of the alert cat. II. Response characteristics to vertical optokinetic stimulation.  

UK PubMed Central (United Kingdom)

Extracellular activity from vestibular nuclei neurons and vertical eye movements were recorded in the alert cat during sinusoidal optokinetic stimulation in the vertical plane at frequencies varying from 0.0125 Hz to 0.75 Hz. Among a population of 96 vestibular units located in and around Deiters' nucleus, 73 neurons (76%) displayed a firing rate modulation which followed the input at the standard parameters of visual stimulation (0.05 Hz; 10.1 deg/s or 9.1 cm/s peak to peak velocity). Two different patterns of modulation were found. In 42 cells (57%) an increase in the firing rate was observed during motion of the visual scene in the downward direction, while 31 neurons (43%) showed the opposite behavior, with an enhanced firing rate during upward movement. The phase of the neuronal responses was close (+/- 45 degrees) to the velocity peaks (+90 degrees: downward and -90 degrees: upward) of visual scene motion for 65 among the 73 neurons. Mean values of phase was -6.1 +/- 19.5 degrees (SD) and -3.2 +/- 15.5 degrees (SD) with respect to the +90 degrees and -90 degrees velocity peaks, respectively. In the frequency range 0.0125-0.75 Hz, the phase of the neuronal responses remained almost stable, with only a slight lag which reaches -22 degrees at the 0.25 Hz visual stimulation. The firing rate modulation was found to be predominant at low frequencies (0.0125 Hz-0.25 Hz), with three distinct peaks of modulation occurring either at 0.025 Hz, 0.10 Hz or 0.25 Hz, depending on the recorded cells. Above 0.5 Hz, the cell modulation was very poorly developed or even absent. A gain attenuation was observed in all units, which was more important in cells showing a peak of modulation at 0.025 Hz as compared with the others (-20.7 dB vs -9.6 dB, respectively, in the 0.025 Hz-0.25 Hz decade). The gain of the optokinetic reflex (OKR) progressively decreased from mean values of 0.78 +/- 0.15 to 0.05 +/- 0.06 in the 0.025 Hz-0.5 Hz frequency range. A close correlation was observed between the OKR slow phase velocity and the modulation of the neuronal responses in the two cell populations with maximal modulations at 0.10 Hz or 0.25 Hz. No correlations were noticed in the third population characterized by a peak of modulation at 0.025 Hz. In all units, the phase of eye movement velocity and of neuronal responses were both related to the velocity of the visual surround motion. These correlations were also found when varying the amplitude of the visual stimulation at a fixed frequency.(ABSTRACT TRUNCATED AT 400 WORDS)

Barthelemy J; Xerri C; Borel L; Lacour M

1988-01-01

60

Representation of Neck Velocity and Neck–Vestibular Interactions in Pursuit Neurons in the Simian Frontal Eye Fields  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The smooth pursuit system must interact with the vestibular system to maintain the accuracy of eye movements in space (i.e., gaze-movement) during head movement. Normally, the head moves on the stationary trunk. Vestibular signals cannot distinguish whether the head or whole body is moving. Neck pro...

Fukushima, Kikuro; Akao, Teppei; Saito, Hiroshi; Kurkin, Sergei A.; Fukushima, Junko; Peterson, Barry W.

 
 
 
 
61

Neuronal coding of linear motion in the vestibular nuclei of the alert cat. III. Dynamic characteristics of visual-otolith interactions.  

UK PubMed Central (United Kingdom)

In the present study we have investigated in the awake cat the response dynamics of vestibular nuclei neurons to visual or/and otolith stimulation elicited by vertical linear motion. Of the 53 units tested during sinusoidal motion at 0.05 Hz (9.1 cm/s), 1 (1.9%) was responsive to the otolith input only, 13 (24.5%) were influenced by the visual input only and 23 (43.4%) responded to both modalities. Neurons were excited either during upward or downward animal or visual surround movement. Most units displayed a firing rate modulation very close to motion velocity. All the neurons receiving convergent visual and otolith inputs (0.05 Hz, 9.1 cm/s) exhibited synergistic patterns of response. Motion velocity coding was improved in terms of input-output phase relationship and response sensitivity when visual and otolith signals were combined. Depending on the units, visual-otolith interactions in single neurons could follow a linear or a nonlinear mode of summation. The dynamic characteristics of visual-otolith interactions were examined in the 0.05 Hz-0.50 Hz frequency bandwidth. Visual signals seemed to predominate over otolith signals at low stimulus frequencies (up to 0.25 Hz), while the contrary was found in the higher frequency range of movement (above 0.25 Hz). The effects of visual stabilization (VS: suppression of visual motion cues) was observed in a small sample of units. As a rule, VS induced a reduction in the amplitude of unit response as compared to visual + otolith stimulation, the lower the motion frequency, the more pronounced the attenuation. VS also decreased the amplitude of the otolith-dependent component of response. The possible modes of visual-vestibular interactions in single cells are discussed. The present study supports the hypothesis that visual and vestibular motion cues are weighted according to their internal relevance.

Xerri C; Barthelemy J; Borel L; Lacour M

1988-01-01

62

Vestibular Hyperacusis  

Science.gov (United States)

Vestibular Hyperacusis Are you sensitive to certain sounds? Hyperacusis is the perception of an unusual auditory sensitivity ... parade to a person with hyperacusis. Cochlear vs. vestibular hyperacusis With cochlear hyperacusis, subjects feel ear pain, ...

63

Heterotrimeric guanosine triphosphate-binding protein-coupled modulatory actions of motilin on K+ channels and postsynaptic ?-aminobutyric acid receptors in mouse medial vestibular nuclear neurons.  

UK PubMed Central (United Kingdom)

Some central nervous system neurons express receptors of gastrointestinal hormones, but their pharmacological actions are not well known. Previous anatomical and unit recording studies suggest that a group of cerebellar Purkinje cells express motilin receptors, and motilin depresses the spike discharges of vestibular nuclear neurons that receive direct cerebellar inhibition in rats or rabbits. Here, by the slice-patch recording method, we examined the pharmacological actions of motilin on the mouse medial vestibular nuclear neurons (MVNs), which play an important role in the control of ocular reflexes. A small number of MVNs, as well as cerebellar floccular Purkinje cells, were labeled with an anti-motilin receptor antibody. Bath application of motilin (0.1 ?m) decreased the discharge frequency of spontaneous action potentials in a group of MVNs in a dose-dependent manner (K(d) , 0.03 ?m). The motilin action on spontaneous action potentials was blocked by apamin (100 nm), a blocker of small-conductance Ca(2+) -activated K(+) channels. Furthermore, motilin enhanced the amplitudes of inhibitory postsynaptic currents (IPSCs) and miniature IPSCs, but did not affect the frequencies of miniature IPSCs. Intracellular application of pertussis toxin (PTx) (0.5 ?g/?L) or guanosine triphosphate-?-S (1 mm) depressed the motilin actions on both action potentials and IPSCs. Only 30% of MVNs examined on slices obtained from wild-type mice, but none of the GABAergic MVNs that were studied on slices obtained from vesicular ?-aminobutyric acid transporter-Venus transgenic mice, showed such a motilin response on action potentials and IPSCs. These findings suggest that motilin could modulate small-conductance Ca(2+) -activated K(+) channels and postsynaptic ?-aminobutyric acid receptors through heterotrimeric guanosine triphosphate-binding protein-coupled receptor in a group of glutamatergic MVNs.

Todaka H; Tatsukawa T; Hashikawa T; Yanagawa Y; Shibuki K; Nagao S

2013-02-01

64

Modulation by acute stress of chloride permeation across microdissected vestibular neurons membranes: different results in two rabbit strains and CRF involvement.  

Science.gov (United States)

Free hand isolation of adult rabbit vestibular Deiters' neurons and dissection of their single membranes allows the study of their ionic permeability characteristics in a microchambers device. In the case of hare-like rabbits, the dissection of such membranes presents evidence of a high basal permeation of labelled chloride, possibly related to mechanical disturbance of the plasma membrane-related cytoskeleton and activation of chloride channels. This did not apply to the laboratory strain of white New Zealand rabbits. However, membranes from hare-like rabbits which were stressed by being rotated on a platform before the experiment, behaved like those from the New Zealand strain. Vice versa, habituation to handling day after day of New Zealand rabbits resulted in a chloride permeation equal to that of unstressed hare-like rabbits. We propose that the stressful conditions result in the release of neurochemical messages to the vestibular Deiters' cells which influence their electrophysiological behavior. The corticotropin releasing factor (CRF), a stress-related peptide present in the climbing fibers, actually blocks the basal chloride permeation across the Deiters' membranes and this effect is partially reversed by its receptor antagonist, alpha-helical CRF [9-41]. PMID:11164791

Rapallino, M V; Cupello, A; Hydén, H; Izvarina, N L

2001-02-01

65

Vestibular "PREHAB".  

Science.gov (United States)

A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness, and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote a compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion caused by the tumor or the surgery of the posterior cranial fossa, there may be a risk of a combined vestibulocerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well-learned everyday activities may go without any prominent symptoms. A pretreatment plan was therefore implemented before planned vestibular lesions, that is, "PREHAB." This was first done in subjects undergoing gentamicin treatment for morbus Ménière. Subjects would perform vestibular exercises for 14 days before the first gentamicin installation, and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. The approach--which is reported here--was then expanded to patients with pontine-angle tumors requiring surgery, but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebellovestibular lesions. Twelve patients were treated with PREHAB and had gentamicin installations transtympanically. In all cases there was a caloric loss, loss of VOR in head impulse tests, and impaired subjective vertical and horizontal. Spontaneous, positional nystagmus, subjective symptoms, and postural function were normalized before surgery and postoperative recovery was swift. Pretreatment training with vestibular exercises continued during the successive loss of vestibular function during gentamicin treatment, and pre-op gentamicin ablation of vestibular function offers a possibility to reduce malaise and speed up recovery. PMID:19645909

Magnusson, Måns; Kahlon, Babar; Karlberg, Mikael; Lindberg, Sven; Siesjö, Peter; Tjernström, Fredrik

2009-05-01

66

Vestibular "PREHAB".  

UK PubMed Central (United Kingdom)

A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness, and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote a compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion caused by the tumor or the surgery of the posterior cranial fossa, there may be a risk of a combined vestibulocerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well-learned everyday activities may go without any prominent symptoms. A pretreatment plan was therefore implemented before planned vestibular lesions, that is, "PREHAB." This was first done in subjects undergoing gentamicin treatment for morbus Ménière. Subjects would perform vestibular exercises for 14 days before the first gentamicin installation, and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. The approach--which is reported here--was then expanded to patients with pontine-angle tumors requiring surgery, but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebellovestibular lesions. Twelve patients were treated with PREHAB and had gentamicin installations transtympanically. In all cases there was a caloric loss, loss of VOR in head impulse tests, and impaired subjective vertical and horizontal. Spontaneous, positional nystagmus, subjective symptoms, and postural function were normalized before surgery and postoperative recovery was swift. Pretreatment training with vestibular exercises continued during the successive loss of vestibular function during gentamicin treatment, and pre-op gentamicin ablation of vestibular function offers a possibility to reduce malaise and speed up recovery.

Magnusson M; Kahlon B; Karlberg M; Lindberg S; Siesjö P; Tjernström F

2009-05-01

67

ACTIVITY OF THE SUPERIOR VESTIBULAR NUCLEI NEURONS AT STIMULATION OF HYPOTHALAMIC PARAVENTRICULAR AND SUPRAOPTIC NUCLEI IN CONDITIONS OF UNILATERAL LABYRINTHECTOMY COMBINED WITH VIBRATION EXPOSURE  

Directory of Open Access Journals (Sweden)

Full Text Available We studied the frequency changes of single neuronal spike activity flow from superior vestibular nucleus (SVN), evoked on high frequency stimulation (HFS) of paraventricular (PV) and supraoptic (SO) nuclei of hypothalamus in Albino rats in conditions of unilateral labyrinthectomy (UL) combined with many days of vibration exposure (VE). Programmed mathematical on-lin? analysis was used. In normal conditions, at bilateral stimulation of PV and SO nuclei the tetanic potentiation (TP) prevaled. After UL in control at uninjured side TP and posttetanic potentiation (PTP) were recorded; on injured side, on the whole, along with variability of initial background activity of SVN neurons, an exiguity of components and of the repeatability of poststimulus excitatory and inhibitory manifestations of SVN neurons’ activity were recorded. Combined action of UL and VE at intact side evoked tetanic depression on ipsilateral stimulation of PV and SO nuclei; on injured side the stimulation of the same nuclei evoked TP and PTP, which achieved normal levels. The results of histochemical investigation in analogous experimental conditions confirmed the electrophysiological data, which allowed us concluding about protective effect of VE.

S.H. Sarkisyan, V.A. Chavushyan, I.B. Meliksetyan, S.M. Minasyan, J.S. Sarkissian

2010-01-01

68

Vestibular rehabilitation.  

UK PubMed Central (United Kingdom)

PURPOSE OF REVIEW: This review examines the research from 2011 through 2012 on treatment efficacy in two common vestibular disorders - vestibular hypofunction and benign paroxysmal positional vertigo (BPPV). RECENT FINDINGS: Significant numbers of randomized controlled trials now support the use of specific exercises for the treatment of patients with unilateral peripheral vestibular hypofunction. We do not know if some treatment approaches are more effective than others. There is preliminary evidence that head movement may be the component critical to recovered function and decreased symptoms. Some patient characteristics and initial assessment results appear to predict treatment outcome but the evidence is incomplete. Treatment of posterior canal BPPV canalithiasis is well established. New evidence supports certain treatments for horizontal canal BPPV. SUMMARY: Treatments for unilateral vestibular hypofunction and for posterior canal BPPV are effective; however, there are many as yet unanswered questions such as why some patients with vestibular hypofunction do not improve with a course of vestibular exercises. We also do not know what would be the best treatment for anterior canal BPPV or for multiple-canal involvement BPPV.

Herdman SJ

2013-02-01

69

Vestibular falls.  

UK PubMed Central (United Kingdom)

Vestibular dysfunction is a significant differential diagnosis in patients who have unexpected falls without: loss of consciousness, paresis, sensory loss, or cerebellar deficit. Either peripheral or central vestibular disorders cause postural instability with preferred directions of falling, some of which can be attributed to either the particular plane of the affected semicircular canal or a central pathway mediating the 3-dimensional vestibulo-ocular reflex in yaw, pitch, and roll. Ipsiversive falls occur in vestibular neuritis or in Wallenberg's syndrome--where they are known as lateropulsion. Contraversive falls are typical for the otolith Tullio phenomenon, vestibular epilepsy, and thalamic astasia. Predominant fore-aft instability is observed in bilateral vestibulopathy, benign paroxysmal positioning vertigo, as well as in downbeat or upbeat nystagmus syndrome. Falls can be diagonally forward (or backward) and toward or away from the side of the lesion, depending on the site of the lesion (the ocular tilt reaction is ipsiversive in medullary lesions, but contraversive in mesencephalic lesions) and on whether vestibular structures are excited or inhibited.

Brandt T; Dieterich M

1993-01-01

70

Vestibular falls.  

Science.gov (United States)

Vestibular dysfunction is a significant differential diagnosis in patients who have unexpected falls without: loss of consciousness, paresis, sensory loss, or cerebellar deficit. Either peripheral or central vestibular disorders cause postural instability with preferred directions of falling, some of which can be attributed to either the particular plane of the affected semicircular canal or a central pathway mediating the 3-dimensional vestibulo-ocular reflex in yaw, pitch, and roll. Ipsiversive falls occur in vestibular neuritis or in Wallenberg's syndrome--where they are known as lateropulsion. Contraversive falls are typical for the otolith Tullio phenomenon, vestibular epilepsy, and thalamic astasia. Predominant fore-aft instability is observed in bilateral vestibulopathy, benign paroxysmal positioning vertigo, as well as in downbeat or upbeat nystagmus syndrome. Falls can be diagonally forward (or backward) and toward or away from the side of the lesion, depending on the site of the lesion (the ocular tilt reaction is ipsiversive in medullary lesions, but contraversive in mesencephalic lesions) and on whether vestibular structures are excited or inhibited. PMID:8275242

Brandt, T; Dieterich, M

1993-01-01

71

Vestibular schowanoma  

Directory of Open Access Journals (Sweden)

Full Text Available Vestibular Schowanoma is one of the most common Intracranial Tumors which has elicited from the Schwann cells in the upper part of vestibular branch of 8th nerve and can affect the cochlear branch too. This benign capsulated tumor  is mostly unilateral. Schowanoma is relatively slow growing. In the current article we have presented the case of a 51 year-old woman complaining Right ear Tinnitus accompanying with numbness of the right side of the face without any sign of vertigo or imbalance. MRI and Auditory Brain stem Responses (ABR) studies demonstrated right side vestibular Schowanoma next to cerebellopontine Angle (CPA). The audiological and imaging findings have been brought here in details.

Massoume Rouzbahani

2000-01-01

72

Procedures for restoring vestibular disorders  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vesti...

Walther, LE

73

Balance (or Vestibular) Rehabilitation  

Science.gov (United States)

... the Public › Hearing and Balance Balance (or Vestibular) Rehabilitation Audiologic (hearing), balance, and medical diagnostic tests help ... whether you are a candidate for vestibular (balance) rehabilitation. Vestibular rehabilitation is an individualized balance retraining exercise ...

74

Vestibular Rehabilitation Therapy (VRT)  

Science.gov (United States)

Vestibular Rehabilitation Therapy (VRT) What is Vestibular Rehabilitation Therapy? Vestibular rehabilitation therapy (VRT) is an exercise-based program designed to promote central nervous system compensation for inner ear deficits. VRT can ...

75

Medication (for Vestibular Disorders)  

Science.gov (United States)

... Exercise Medication Surgical Procedures Types of Vestibular Disorders Medication Can Medication Help Me Feel Better? The use of medication in treating vestibular disorders depends on whether the ...

76

Expression of calcitonin gene-related peptide in efferent vestibular system and vestibular nucleus in rats with motion sickness.  

UK PubMed Central (United Kingdom)

UNLABELLED: Motion sickness presents a challenge due to its high incidence and unknown pathogenesis although it is a known fact that a functioning vestibular system is essential for the perception of motion sickness. Recent studies show that the efferent vestibular neurons contain calcitonin gene-related peptide (CGRP). It is a possibility that the CGRP immunoreactivity (CGRPi) fibers of the efferent vestibular system modulate primary afferent input into the central nervous system; thus, making it likely that CGRP plays a key role in motion sickness. To elucidate the relationship between motion sickness and CGRP, the effects of CGRP on the vestibular efferent nucleus and the vestibular nucleus were investigated in rats with motion sickness. METHODS: An animal model of motion sickness was created by subjecting rats to rotary stimulation for 30 minutes via a trapezoidal stimulation pattern. The number of CGRPi neurons in the vestibular efferent nucleus at the level of the facial nerve genu and the expression level of CGRPi in the vestibular nucleus of rats were measured. Using the ABC method of immunohistochemistry technique, measurements were taken before and after rotary stimulation. The effects of anisodamine on the expression of CGRP in the vestibular efferent nucleus and the vestibular nucleus of rats with motion sickness were also investigated. RESULTS AND DISCUSSION: Both the number of CGRPi neurons in the vestibular efferent nucleus and expression level in the vestibular nucleus increased significantly in rats with motion sickness compared to that of controls. The increase of CGRP expression in rats subjected to rotary stimulation 3 times was greater than those having only one-time stimulation. Administration of anisodamine decreased the expression of CGRP within the vestibular efferent nucleus and the vestibular nucleus in rats subjected to rotary stimulation. In conclusion, CGRP possibly plays a role in motion sickness and its mechanism merits further investigation.

Xiaocheng W; Zhaohui S; Junhui X; Lei Z; Lining F; Zuoming Z

2012-01-01

77

Expression of Calcitonin Gene-Related Peptide in Efferent Vestibular System and Vestibular Nucleus in Rats with Motion Sickness  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Motion sickness presents a challenge due to its high incidence and unknown pathogenesis although it is a known fact that a functioning vestibular system is essential for the perception of motion sickness. Recent studies show that the efferent vestibular neurons contain calcitonin gene-related peptid...

Xiaocheng, Wang; Zhaohui, Shi; Junhui, Xue; Lei, Zhang; Lining, Feng; Zuoming, Zhang

78

Procedures for restoring vestibular disorders.  

UK PubMed Central (United Kingdom)

This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 (Tab. 1) and 2 (Tab. 2)). Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease). Although balance training does improve the patient's sense of balance, it will not restore it completely.In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine). In addition, there are non-ablative (sacculotomy) as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve). In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers). In very rare cases it may be necessary to carry out a semicircular canal occlusion.Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of the round window membrane can, for example, also be caused by an implosive inner ear barotrauma during the decompression phase of diving. Dehiscence of the anterior semicircular canal, a relatively rare disorder, can be treated conservatively (avoiding stimuli which cause dizziness), by non-ablative "resurfacing" or by "plugging" the semicircular canal. A perilymph fistula can cause a Tullio-phenomenon resulting from a traumatic dislocation or hypermobility of the stapes, which can be surgically corrected. Vestibular disorders can also result from otosurgical therapy. When balance disorders persist following stapedectomy it is necessary to carry out a revision operation in order to either exclude a perilymph fistula or shorten the piston. Surgically reducing the size of open mastoid cavities (using for example porous hydroxylapatite or cartilage) can result in a reduction of vertiginous symptoms while nursing or during exposure to ambient air. Vestibular disturbances can occur both before and after vestibular nerve surgery (acoustic neuroma). Initially, good vestibular compensation can be expected after surgically removing the acoustic neuroma. An aberrant regeneration of nerve fibers of the vestibulocochlear nerve has been suggested as a cause for secondary worsening. Episodes of vertigo can be caused by an irritation of the vestibular nerve (vascular loop). Neurovascular decompression is generally regarded as the best surgical therapy. In the elderly, vestibular disturbances can severely limit quality of life and are often aggravated by multiple comorbidities. Antivertiginous drugs (e.g. dimenhydrinate) in combination with movement training can significantly reduce symptoms. Administering antivertiginous drugs over varying periods of time (e.g. transdermal scopolamine application via patches) as well as kinetosis training can be used as both prophylactically and as a therapy for kinetosis. Exposure training should be used as a prophylactic for height vertigo.

Walther LE

2005-01-01

79

Procedures for restoring vestibular disorders.  

Science.gov (United States)

This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 (Tab. 1) and 2 (Tab. 2)). Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease). Although balance training does improve the patient's sense of balance, it will not restore it completely.In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine). In addition, there are non-ablative (sacculotomy) as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve). In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers). In very rare cases it may be necessary to carry out a semicircular canal occlusion.Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of the round window membrane can, for example, also be caused by an implosive inner ear barotrauma during the decompression phase of diving. Dehiscence of the anterior semicircular canal, a relatively rare disorder, can be treated conservatively (avoiding stimuli which cause dizziness), by non-ablative "resurfacing" or by "plugging" the semicircular canal. A perilymph fistula can cause a Tullio-phenomenon resulting from a traumatic dislocation or hypermobility of the stapes, which can be surgically corrected. Vestibular disorders can also result from otosurgical therapy. When balance disorders persist following stapedectomy it is necessary to carry out a revision operation in order to either exclude a perilymph fistula or shorten the piston. Surgically reducing the size of open mastoid cavities (using for example porous hydroxylapatite or cartilage) can result in a reduction of vertiginous symptoms while nursing or during exposure to ambient air. Vestibular disturbances can occur both before and after vestibular nerve surgery (acoustic neuroma). Initially, good vestibular compensation can be expected after surgically removing the acoustic neuroma. An aberrant regeneration of nerve fibers of the vestibulocochlear nerve has been suggested as a cause for secondary worsening. Episodes of vertigo can be caused by an irritation of the vestibular nerve (vascular loop). Neurovascular decompression is generally regarded as the best surgical therapy. In the elderly, vestibular disturbances can severely limit quality of life and are often aggravated by multiple comorbidities. Antivertiginous drugs (e.g. dimenhydrinate) in combination with movement training can significantly reduce symptoms. Administering antivertiginous drugs over varying periods of time (e.g. transdermal scopolamine application via patches) as well as kinetosis training can be used as both prophylactically and as a therapy for kinetosis. Exposure training should be used as a prophylactic for height vertigo. PMID:22073053

Walther, Leif Erik

2005-09-28

80

Procedures for restoring vestibular disorders  

Directory of Open Access Journals (Sweden)

Full Text Available This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 and 2). Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease). Although balance training does improve the patient's sense of balance, it will not restore it completely.In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine). In addition, there are non-ablative (sacculotomy) as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve). In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers). In very rare cases it may be necessary to carry out a semicircular canal occlusion. Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of the round window membrane can, for example, also be caused by an implosive inner ear barotrauma during the decompression phase of diving. Dehiscence of the anterior semicircular canal, a relatively rare disorder, can be treated conservatively (avoiding stimuli which cause dizziness), by non-ablative „resurfacing" or by „plugging" the semicircular canal. A perilymph fistula can cause a Tullio-phenomenon resulting from a traumatic dislocation or hypermobility of the stapes, which can be surgically corrected. Vestibular disorders can also result from otosurgical therapy. When balance disorders persist following stapedectomy it is necessary to carry out a revision operation in order to either exclude a perilymph fistula or shorten the piston. Surgically reducing the size of open mastoid cavities (using for example porous hydroxylapatite or cartilage) can result in a reduction of vertiginous symptoms while nursing or during exposure to ambient air. Vestibular disturbances can occur both before and after vestibular nerve surgery (acoustic neuroma). Initially, good vestibular compensation can be expected after surgically removing the acoustic neuroma. An aberrant regeneration of nerve fibers of the vestibulocochlear nerve has been suggested as a cause for secondary worsening. Episodes of vertigo can be caused by an irritation of the vestibular nerve (vascular loop). Neurovascular decompression is generally regarded as the best surgical therapy. In the elderly, vestibular disturbances can severely limit quality of life and are often aggravated by multiple comorbidities. Antivertiginous drugs (e.g. dimenhydrinate) in combination with movement training can significantly reduce symptoms. Administering antivertiginous drugs over varying periods of time (e.g. transdermal scopolamine application via patches) as well as kinetosis training can be used as both prophylactically and as a therapy for kinetosis. Exposure training should be used as a prophylactic for height vertigo.

Walther, Leif Erik

2005-01-01

 
 
 
 
81

Vestibular Disorders Association  

Science.gov (United States)

... find a doctor with a special interest in vestibular disorders." Click here to search our provider directory. ... live an active and productive life with a vestibular disorder." How can I help others? Read more " ...

82

Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises  

Directory of Open Access Journals (Sweden)

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.

Esther Bernal Valls; Víctor Faus Cuñat; Raquel Bernal Valls

2006-01-01

83

Vestibular perception following acute unilateral vestibular lesions.  

UK PubMed Central (United Kingdom)

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 perceptual processes (ultimately cortical) participating in vestibular compensation, suppressing asymmetry acutely in unilateral vestibular lesions.

Cousins S; Kaski D; Cutfield N; Seemungal B; Golding JF; Gresty M; Glasauer S; Bronstein AM

2013-01-01

84

Noise Induced Vestibular Damage  

Directory of Open Access Journals (Sweden)

Full Text Available There are increasing evidences about the vestibular damage caused by the exposure to noise. Histological and functional derangements of the vestibular system have been reported in laboratory animals exposed to high levels of noise. However, clinical series describe contradictory results with regard to vestibular disturbances in industrial workers and military personnel suffering from noise induced hearing loss (NIHL). Animal studies have proved that crista ampullaris bears the most disturbances, though some damages have been also detected in macula of the utricle and saccule and utricle. These changes have been induced due to acoustical pressure on the vestibular labyrinth. The findings from the experiments regarding vestibular function in patients suffering NIHL have shown a paramount diminish in vestibulo-occular Reflex (VOR). The correlation among NIHL, VOR and unilateral caloric weakness were statistically significant which can be due to a common mechanism of disturbances in the function of cochlea and vestibule.

Maryam Emadi

1999-01-01

85

Peripheral vestibular disorders.  

UK PubMed Central (United Kingdom)

PURPOSE OF REVIEW: First, to update the diagnosis, pathophysiology, and treatment of the most frequent peripheral vestibular disorders. Second, to identify those disorders for which the diagnostic criteria are still deficient and treatment trials are still lacking. RECENT FINDINGS: Bilateral vestibulopathy can be reliably diagnosed by the head-impulse test, caloric irrigation, and vestibular-evoked myogenic potentials. A new frequent subtype has been described: cerebellar ataxia, neuropathy, and vestibular areflexia syndrome. Benign paroxysmal positioning vertigo can be easily diagnosed and effectively treated. Vestibular neuritis is most likely caused by the reactivation of a herpes simplex type 1 infection; the inferior vestibular nerve subtype is now well established. More evidence is needed that the recovery can be improved by corticosteroids. Endolymphatic hydrops in Menière's disease can be depicted by high-resolution MRI after transtympanic gadolinium injection; a high-dosage and long-term prophylactic treatment with betahistine is evidently effective. Its mechanism of action is most likely an increase in the inner-ear blood flow. Vestibular paroxysmia is now a well established entity; carbamazepine is the treatment of first choice. Superior canal dehiscence syndrome can be reliably diagnosed; the best current treatment option is canal plugging. SUMMARY: Although progress has been made in the diagnosis and treatment of most peripheral vestibular disorders, more state-of-the-art trials are needed on the treatment of bilateral vestibulopathy to prove the efficacy of balance training, of vestibular neuritis (in terms of recovery of peripheral vestibular function and central compensation), of vestibular paroxysmia to prove the effects of carbamazepine, and of Menière's disease to find the optimal dosage of betahistine.

Strupp M; Brandt T

2013-02-01

86

Deregulated genes in sporadic vestibular schwannomas  

DEFF Research Database (Denmark)

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.

Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea

2010-01-01

87

Specific vestibular exercises in the treatment of vestibular neuritis  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction Vestibular neuritis rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. Rehabilitation The program of vestibular rehabilitation presents a major achievement in the field of treatment of balance disorders. Vestibular compensation is associated with central sensory reintegration and bilaterally equalizes the vestibular tonus over a period of time. Material and methods In this retrospective study of a series of cases authors present their results in 58 patients undergoing a program of vestibular rehabilitation. Patients were divided into two groups. Thirty patients were in group I, and 28 in group II. Specific vestibular exercises were conducted in group I, and non-specific exercises in group II. Analysis of effects of vestibular compensation was made due electronystagmography. Results Results were satisfactory in both groups of patients. Absence of spontaneous nystagmus was detected in 83.3% of patients in group I (specific vestibular exercises) and in 53.5% of patients in group II (non-specific exercises), with an average treatment time of up to 2 months. Harmonization of pendular stimulation was detected in 83.3% and 60.7% of patients in groups I and II, respectively. Conclusion Early physiotherapeutic vestibular rehabilitation supports the vestibular compensation mechanism. At the same time vestibular rehabilitation may prevent panic disorder caused by hyperventilation syndrome.

Komazec Zoran; Lemaji? Slobodanka N.

2004-01-01

88

Vulvar vestibular papillomatosis  

Directory of Open Access Journals (Sweden)

Full Text Available Vulvar vestibular papillomatosis is considered an anatomical variant of the vulva. Recognition of this condition enables one to distinguish it from warts and therefore avoid unnecessary therapy. A 29-year-old lady presented to this clinic with a history of ?small growths? in her vulva since two years. Examination identified skin colored translucent papules; some of them appeared digitate and were seen on the vestibule and inner aspect of both labia minora. They were soft to feel and non-tender. Few lesions looked like elongated pearly penile papules. A provisional diagnosis of vestibular papillomatosis was made and a biopsy was done. It showed finger-like protrusions of loosely arranged subdermal tissue with blood vessels and which were covered by normal mucosal epithelium. No koilocytes were seen and the diagnosis of vestibular papillomatosis was confirmed. We believe that this is the first case report of vulvar vestibular papillomatosis in Indian dermatologic literature.

Wollina U; Verma Shyam

2010-01-01

89

Bilateral vestibular loss.  

Science.gov (United States)

Bilateral vestibular loss is a rare cause of visual disturbance (oscillopsia) and imbalance. When severe, the most common cause is iatrogenic-gentamicin ototoxicity. Bilateral loss is easily diagnosed at the bedside with the dynamic illegible E test. If this test is omitted, it can easily be misdiagnosed as a cerebellar syndrome. Treatment is largely supportive. Care should be taken to avoid medications that suppress vestibular function, and to encourage activity. PMID:24057822

Hain, Timothy C; Cherchi, Marcello; Yacovino, Dario A

2013-09-21

90

Bilateral vestibular loss.  

UK PubMed Central (United Kingdom)

Bilateral vestibular loss is a rare cause of visual disturbance (oscillopsia) and imbalance. When severe, the most common cause is iatrogenic-gentamicin ototoxicity. Bilateral loss is easily diagnosed at the bedside with the dynamic illegible E test. If this test is omitted, it can easily be misdiagnosed as a cerebellar syndrome. Treatment is largely supportive. Care should be taken to avoid medications that suppress vestibular function, and to encourage activity.

Hain TC; Cherchi M; Yacovino DA

2013-07-01

91

Vestibular primary afferent responses to sound and vibration in the guinea pig.  

UK PubMed Central (United Kingdom)

This study tested whether air-conducted sound and bone-conducted vibration activated primary vestibular afferent neurons and whether, at low levels, such stimuli are specific to particular vestibular sense organs. In response to 500 Hz bone-conducted vibration or 500 Hz air-conducted sound, primary vestibular afferent neurons in the guinea pig fall into one of two categories--some neurons show no measurable change in firing up to 2 g peak-to-peak or 140 dB SPL. These are semicircular canal neurons (regular or irregular) and regular otolith neurons. In sharp contrast, otolith irregular neurons show high sensitivity: a steep increase in firing as stimulus intensity is increased. These sensitive neurons typically, but not invariably, were activated by both bone-conducted vibration and air-conducted sound, they originate from both the utricular and saccular maculae, and their sensitivity underpins new clinical tests of otolith function.

Curthoys IS; Vulovic V

2011-05-01

92

Convergence of vestibular and neck proprioceptive sensory signals in the cerebellar interpositus.  

UK PubMed Central (United Kingdom)

The cerebellar interpositus nucleus (IN) contributes to controlling voluntary limb movements. We hypothesized that the vestibular signals within the IN might be transformed into coordinates describing the body's movement, appropriate for controlling limb movement. We tested this hypothesis by recording from IN neurons in alert squirrel monkeys during vestibular and proprioceptive stimulation produced during (1) yaw head-on-trunk rotation about the C1-C2 axis while in an orthograde posture and (2) lateral side-to-side flexion about the C6-T3 axis while in a pronograde posture. Neurons (44/67) were sensitive to vestibular stimulation (23/44 to rotation and translation, 14/44 to rotation only, 7/44 to translation only). Most neurons responded during contralateral movement. Neurons (29/44) had proprioceptive responses; the majority (21/29) were activated during neck rotation and lateral flexion. In all 29 neurons with convergent vestibular and neck proprioceptive input those inputs functionally canceled each other during all combined sensory stimulation, whether in the orthograde or pronograde posture. These results suggest that two distinct populations of IN neurons exist, each of which has vestibular sensitivity. One population carries vestibular signals that describe the head's movement in space as is traditional for vestibular signals without proprioceptive signals. A second population of neurons demonstrated precise matching of vestibular and proprioceptive signals, even for complicated stimuli, which activated the semicircular canals and otolith organs and involved both rotation and flexion in the spine. Such neurons code body (not head) motion in space, which may be the appropriate platform for controlling limb movements.

Luan H; Gdowski MJ; Newlands SD; Gdowski GT

2013-01-01

93

[The vestibular system: from structure to function].  

Science.gov (United States)

The two vestibular receptors, right and left, hidden in the petrous part of the temporal bone with the cochlear receptors, receive information from angular and linear movements of the head and transform them into a nerve message sent to the nuclei of the brainstem, which are connected directly on the one hand to the oculomotor nuclei, at the origin of the oculovestibular reflex (induction of nystagmus), and on the other hand, to the spinal motor neurons, at the origin of the vestibulospinal reflex. These reflexes are associated with responses to visual and somaesthetic information for maintenance or return to the standing position, which characterises the function of equilibrium. Vertigo and disorders of balance reflect a conflict of information between these two labyrinths, or between the vestibular apparatus and the messages issued by other captors, and sometimes also dysfunction of central nervous system treatment of information or a lesion of the effector motor systems. PMID:8178092

Collard, M

1994-02-01

94

[The vestibular system: from structure to function  

UK PubMed Central (United Kingdom)

The two vestibular receptors, right and left, hidden in the petrous part of the temporal bone with the cochlear receptors, receive information from angular and linear movements of the head and transform them into a nerve message sent to the nuclei of the brainstem, which are connected directly on the one hand to the oculomotor nuclei, at the origin of the oculovestibular reflex (induction of nystagmus), and on the other hand, to the spinal motor neurons, at the origin of the vestibulospinal reflex. These reflexes are associated with responses to visual and somaesthetic information for maintenance or return to the standing position, which characterises the function of equilibrium. Vertigo and disorders of balance reflect a conflict of information between these two labyrinths, or between the vestibular apparatus and the messages issued by other captors, and sometimes also dysfunction of central nervous system treatment of information or a lesion of the effector motor systems.

Collard M

1994-02-01

95

Vestibular schwannoma surgical treatment.  

UK PubMed Central (United Kingdom)

Neurosurgical intervention remains the main step in the effective management of vestibular schwannomas. Extensive studies on vestibular schwannoma treatment have placed emphasis on preserving quality of life and neurological functions, particularly of the facial and vestibulocochlear nerves. Facial nerve preservation and hearing preservation have been achieved by significant advances in skull base microsurgical techniques and intraoperative neuromonitoring. Diffusion tensor imaging is a powerful and accurate method for preoperatively identifying the facial nerve in relation to vestibular schwannomas. Endoscopy offers excellent illumination of the anatomical structures and provides panoramic vision inside the surgical area. In this report, we focused on facial nerve and vestibulocochlear nerve preservation and analyzed the major techniques used for identifying the nerve-tumor relationship.

You YP; Zhang JX; Lu AL; Liu N

2013-05-01

96

Dyscalculia and vestibular function.  

UK PubMed Central (United Kingdom)

BACKGROUND: 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. OBJECTIVES: 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'). RESULTS AND CONCLUSION: The evidence supporting this hypothesis is summarised and potential experiments to test it are proposed.

Smith PF

2012-10-01

97

Vestibular schwannoma mimicking horizontal cupulolithiasis.  

Science.gov (United States)

Positional vertigo and nystagmus can be due to canalithiasis, cupulolithiasis and less commonly, an underlying peripheral or central vestibular disorder. We present a patient with vestibular schwannoma who initially sought treatment for positioning vertigo. Video-oculography on the roll-test revealed direction-changing horizontal apogeotropic nystagmus, consistent with horizontal cupulolithiasis. However, further audio-vestibular investigations and imaging confirmed a right vestibulopathy attributable to a schwannoma of the right vestibular nerve. This case report suggests that vestibular schwannoma should be considered as another potential mimicker of horizontal cupulolithiasis. PMID:23665081

Taylor, Rachael L; Chen, Luke; Lechner, Corinna; Aw, Swee T; Welgampola, Miriam S

2013-05-09

98

Vestibular migraine: Diagnosis and treatment  

Directory of Open Access Journals (Sweden)

Full Text Available Vestibular migraine is one of the most common causes of recurrent vertigo. Ocasionally, diagnosis of vestibular migraine can not be easy because of variety of clinical manifestations. A good characterization of the vestibular migraine and goods diagnostic criteria are necessary in order to treat the vestibular migraine easily. In the other hand, the treatment of vestibular migraine is similar to the treatment of migraine, both acute crisis and preventive treatment. There are several consensus papers in diagnosis and treatment that are analized in this work.

Batuecas-Caletrio A; Martín-Sanz E; Trinidad-Ruíz G; Espinosa-Sánchez JM; Alemán-López O

2013-01-01

99

Vestibular-Ocular Reflex  

Science.gov (United States)

In this activity, learners will perform various investigations to understand the vestibular-ocular reflex and learn about the importance of visual cues in maintaining balance. During the two-part activity, learners will compare the stability of a moving image under two conditions as well as compare the effects of rotation on the sensation of spinning under varying conditions. This lesson guide includes background information, review and critical thinking questions with answers, and handouts. Educators can also use this activity to discuss how the brain functions in space and how researchers study the vestibular function in space.

Marlene Y. Macleish, Ed D.; Bernice R. Mclean, M. E.

2013-01-30

100

Vertigo and vestibular rehabilitation.  

Directory of Open Access Journals (Sweden)

Full Text Available The role of rehabilitation in the management of vertigo is limited to a very specific group of conditions. An Occupational therapist who is a part of the multidisciplinary team treating the vertiginous patient, with the knowledge of physiology and therapeutic benefit of vestibular rehabilitation can widen the rehabilitation spectrum for various diseases producing vertigo and dysequilibrium, to resolve or minimise these symptoms. The present article reviews the need for vestibular rehabilitation and the different conditions needing the same along with its characteristics, physiology and various exercises prescribed.

Konnur M

2000-01-01

 
 
 
 
101

The challenge of vestibular migraine.  

UK PubMed Central (United Kingdom)

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

Sargent EW

2013-10-01

102

Replacing semicircular canal function with a vestibular implant.  

UK PubMed Central (United Kingdom)

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

Merfeld DM; Lewis RF

2012-10-01

103

Neuronal activity in the lateral vestibular nucleus of the cat. V. Topographical distribution of inhibitory effects mediated by the spino-olivocerebellar pathway.  

UK PubMed Central (United Kingdom)

The spatial distribution of inhibitory effects mediated by spinoolivocerebellar pathways and evoked by stimulation of the FRA was studied in Deiters' nucleus by intracellular recordings and extracellular measurements of positive field potentials. At a geven recording site individual nerves greatly varied in their effectiveness: Q and Saph, Tib and FDL were usually the most effective, while GS had very little effect. When comparing several recording sites, various patterns of dominating and nondominating nerves were found, resulting in a somewhat patchy distribution of responses. The results were supported by intracellular recordings, which showed that CF-mediated IPSPs can be evoked from a limited number of nerves only. The findings show that a discriminative pattern exists in the FRA-evoked spino-olivocerebellar-mediated inhibition. In addition, Deiters neurones were found in which the inhibition was evoked from a large number of fore- and hindlimb nerves. Such a generalized inhibitory pattern may be involved in interlimb coordination during locomotion.

ten Bruggencate G; Scherer H; Teichmann R

1975-11-01

104

Pediatric Vestibular Disorders  

Science.gov (United States)

... acronyms, but it is not the same as benign paroxysmal positional vertigo (BPPV). Vestibular neuritis causes dizziness, and labyrinthitis causes both ... the inner ear’s endolymph to the endolymphatic sac). Benign paroxysmal positional vertigo (BPPV) , a condition caused by dislodged otoconia in ...

105

Enlarged Vestibular Aqueducts and Childhood Hearing Loss  

Science.gov (United States)

... Enlarged Vestibular Aqueducts and Childhood Hearing Loss Enlarged Vestibular Aqueducts and Childhood Hearing Loss On this page: ... Where can I find additional information? What are vestibular aqueducts? Diagram of the inner ear. View larger ...

106

Audiologic diagnostics of vestibular schwannoma  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction Vestibular schwannoma (acoustic neuroma) is a rare, but important cause of sensorineural hearing loss. Patients with asymmetric hearing loss, or unilateral tinnitus should be evaluated expeditiously, to prevent further neurological damage. Audiologic diagnostics Audiologic diagnostics represents the basic diagnosis for early detection of vestibular schwannoma. Patients with vestibular schwannomas may present with a variety of clinical features, including retrocochlear pattern of sensorineural hearing loss. Supraliminary audiometry, tympano- metry, stapedius reflex and otoacoustic emissions as well as vestibular response to caloric testing are methods for selection of patients with suspicion of this tumor. Conclusion The golden standard for audiologic diagnostics of vestibular schwannoma is BAEP (Brainstem Auditory Evoked Potentials). Patients with pathological findings of BAEP should undergo MRI of the posterior fossa. Gadolinium-enhanced magnetic resonance imaging is the best and final tool for making a diagnosis of vestibular schwannoma.

Komazec Zoran; Lemaji? Slobodanka N.; Vlaški Ljiljana

2004-01-01

107

Vestibular rehabilitation: rationale and indications.  

UK PubMed Central (United Kingdom)

Treatment options of the patient with dizziness include medication, rehabilitation with physical therapy, surgery, counseling, and reassurance. Here the authors discuss vestibular rehabilitation for patients with benign paroxysmal positional vertigo (BPPV), unilateral vestibular loss or hypofunction, and bilateral vestibular loss/hypofunction. They describe the different mechanisms for recovery with vestibular rehabilitation, the exercises that are used, and which ones are best. An exhaustive literature review on clinical outcomes with the best research publications for BPPV, unilateral vestibular loss/hypofunction, and bilateral vestibular loss/hypofunction is presented. For BPPV, the authors also summarize the evidence-based review practice parameters published in Neurology by Fife et al. (2008) and review all relevant articles published since then.

Cabrera Kang CM; Tusa RJ

2013-07-01

108

Vestibular rehabilitation: rationale and indications.  

Science.gov (United States)

Treatment options of the patient with dizziness include medication, rehabilitation with physical therapy, surgery, counseling, and reassurance. Here the authors discuss vestibular rehabilitation for patients with benign paroxysmal positional vertigo (BPPV), unilateral vestibular loss or hypofunction, and bilateral vestibular loss/hypofunction. They describe the different mechanisms for recovery with vestibular rehabilitation, the exercises that are used, and which ones are best. An exhaustive literature review on clinical outcomes with the best research publications for BPPV, unilateral vestibular loss/hypofunction, and bilateral vestibular loss/hypofunction is presented. For BPPV, the authors also summarize the evidence-based review practice parameters published in Neurology by Fife et al. (2008) and review all relevant articles published since then. PMID:24057831

Cabrera Kang, Christian M; Tusa, Ronald J

2013-09-21

109

[Disability and vestibular pathology  

UK PubMed Central (United Kingdom)

OBJECTIVE: To probe the ability in differentiate the handicap degree among patients with peripheral vestibular illness by means of a questionnaire carefully thought with this purpose. DESIGN: Prospective study covering 2 years (May 1st. 1991 till May the 1st. 1996). FIELD OF STUDY: Patients from the Health Area of Zamora, ambulatory attended at Otolaryngology Department, complaining of peripheral vestibular troubles. INDIVIDUALS INCLUDED: 60 patients diagnosed as paroxitic positional vertigo or Ménière's disease, lasting the discomfort either 6 weeks or less or 2 years or more, the totality split into 4 groups, of 15 individuals each. SCORING: Analysis of the performed scores of the first valuation by means of the Questionnaire for Assessment of the Disability in Vestibular Pathology (Q.A.D.V.P.). Descriptive statistics were performed for each group and each scale. RESULTS: Patients with more than 2 years of evolvement present themselves, usually, with higher scores in both emotional and functional scales if compared with those resulting from patients suffering from paroxistic positional vertigo. CONCLUSIONS: The Q.A.D.V.P. is a measure instrument very useful, by allowing the differentiation of several degrees of disabled people of our studied samples.

Pardal Refoyo JL

2000-01-01

110

Vestibular tributaries to the vein of the vestibular aqueduct.  

DEFF Research Database (Denmark)

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

Hansen, Jesper Marsner; Qvortrup, Klaus

2010-01-01

111

Spatiotemporal properties of optic flow and vestibular tuning in the cerebellar nodulus and uvula.  

UK PubMed Central (United Kingdom)

Convergence of visual motion and vestibular information is essential for accurate spatial navigation. Such multisensory integration has been shown in cortex, e.g., the dorsal medial superior temporal (MSTd) and ventral intraparietal (VIP) areas, but not in the parieto-insular vestibular cortex (PIVC). Whether similar convergence occurs subcortically remains unknown. Many Purkinje cells in vermal lobules 10 (nodulus) and 9 (uvula) of the macaque cerebellum are tuned to vestibular translation stimuli, yet little is known about their visual motion responsiveness. Here we show the existence of translational optic flow-tuned Purkinje cells, found exclusively in the anterior part of the nodulus and ventral uvula, near the midline. Vestibular responses of Purkinje cells showed a remarkable similarity to those in MSTd (but not PIVC or VIP) neurons, in terms of both response latency and relative contributions of velocity, acceleration, and position components. In contrast, the spatiotemporal properties of optic flow responses differed from those in MSTd, and matched the vestibular properties of these neurons. Compared with MSTd, optic flow responses of Purkinje cells showed smaller velocity contributions and larger visual motion acceleration responses. The remarkable similarity between the nodulus/uvula and MSTd vestibular translation responsiveness suggests a functional coupling between the two areas for vestibular processing of self-motion information.

Yakusheva TA; Blazquez PM; Chen A; Angelaki DE

2013-09-01

112

Vestibular contributions to bodily awareness.  

UK PubMed Central (United Kingdom)

The vestibular system has widespread interactions with multisensory cortical networks, including the somatosensory areas. Several clinical observations suggested that vestibular signals are essential to compute more abstract cognitive representations of the body. However, the existing literature is generally based on isolated reports. We aimed to provide both a theoretical framework, and an experimental method to investigate potential vestibular contributions to somatic cognition. Accordingly, we have investigated effects of galvanic vestibular stimulation (GVS) on the localisation of a stimulus on the skin of the hand (a process that we define as somatoperception) and on the implicit representation of the hand size and shape (involving a different process which we define as somatorepresentation). Vestibular input influenced the localisation of tactile stimuli on the hand: touches on the dorsum of the hand were perceived as shifted toward the wrist. The specific polarity of vestibular stimulation influences the localisation errors. Right anodal and left cathodal, which influences both cerebral hemispheres, induced a stronger localisation bias compared to left anodal and right cathodal GVS, which influences primarily the right hemisphere. Although our data confirmed previous findings that the body model of the shape of the hand is massively distorted, vestibular inputs do not contribute to these distortions. Our results suggest that vestibular input influences the registration of somatosensory input onto a map of the body (somatoperception), but does not influence stored knowledge about the spatial organisation of the body as a physical object (somatorepresentation).

Ferrè ER; Vagnoni E; Haggard P

2013-07-01

113

Childhood Vestibular Disorders: A Tutorial  

Science.gov (United States)

There is a growing body of evidence that childhood disorders affecting the vestibular system, although rare, do exist. Describing symptoms associated with the vestibular mechanism for children may be difficult, resulting in misdiagnosing or under-diagnosing these conditions. The pathophysiology, symptoms, and management options of the more common…

Mehta, Zarin; Stakiw, Daria B.

2004-01-01

114

The Vestibular Implant: Quo Vadis?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Objective: To assess the progress of the development of the vestibular implant (VI) and its feasibility short-term. Data sources: A search was performed in Pubmed, Medline, and Embase. Key words used were “vestibular prosth*” and “VI.” The only search limit was language: English or Dutch. Additional...

van de Berg, Raymond; Guinand, Nils; Stokroos, Robert J.; Guyot, Jean-Philippe; Kingma, Herman

115

Radiosurgery for vestibular schwannomas.  

UK PubMed Central (United Kingdom)

This article investigates the role of radiosurgery and stereotactic radiotherapy in the management of vestibular schwannomas (VS), reviewing the authors' own prospective cohort and the current literature. For patients with large Stage IV VS (according to the Koos classification), a combined approach with deliberate partial microsurgical removal followed by radiosurgery to the residual tumor is proposed. The authors' cohort is unique with respect to the size of the population and the length of the follow-up, and demonstrates the efficacy and safety of VS radiosurgery, with particular regard to its high rate of hearing preservation.

Régis J; Carron R; Delsanti C; Porcheron D; Thomassin JM; Murracciole X; Roche PH

2013-10-01

116

Radiosurgery for vestibular schwannomas.  

Science.gov (United States)

This article investigates the role of radiosurgery and stereotactic radiotherapy in the management of vestibular schwannomas (VS), reviewing the authors' own prospective cohort and the current literature. For patients with large Stage IV VS (according to the Koos classification), a combined approach with deliberate partial microsurgical removal followed by radiosurgery to the residual tumor is proposed. The authors' cohort is unique with respect to the size of the population and the length of the follow-up, and demonstrates the efficacy and safety of VS radiosurgery, with particular regard to its high rate of hearing preservation. PMID:24093570

Régis, Jean; Carron, Romain; Delsanti, Christine; Porcheron, Denis; Thomassin, Jean-Marc; Murracciole, Xavier; Roche, Pierre-Hugues

2013-08-02

117

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

Science.gov (United States)

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(2+) from those neurons and perhaps prevent cell damage following UVD. PMID:17275794

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

2006-12-30

118

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

UK PubMed Central (United Kingdom)

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.

Rácz E; Gaál B; Kecskes S; Matesz C

2013-05-01

119

Vestibular hearing and neural synchronization.  

UK PubMed Central (United Kingdom)

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.

Emami SF; Daneshi A

2012-01-01

120

Vestibular findings in fibromyalgia patients  

Directory of Open Access Journals (Sweden)

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.

Zeigelboim, Bianca Simone; Moreira, Denise Nunnes

2011-01-01

 
 
 
 
121

Vestibular migraine: clinical aspects and pathophysiology.  

UK PubMed Central (United Kingdom)

Vestibular migraine is becoming recognised as a distinct clinical entity that accounts for a high proportion of patients with vestibular symptoms. A temporal overlap between vestibular symptoms, such as vertigo and head-movement intolerance, and migraine symptoms, such as headache, photophobia, and phonophobia, is a requisite diagnostic criterion. Physical examination and laboratory testing are usually normal in vestibular migraine but can be used to rule out other vestibular disorders with overlapping symptoms. The pathophysiology of vestibular migraine is incompletely understood but plausibly could include neuroanatomical pathways to and from central vestibular structures and neurochemical modulation via the locus coeruleus and raphe nuclei. In the absence of controlled trials, treatment options for patients with vestibular migraine largely mirror those for migraine headache.

Furman JM; Marcus DA; Balaban CD

2013-07-01

122

Processing of vestibular inputs by the medullary lateral tegmental field of conscious cats: implications for generation of motion sickness.  

UK PubMed Central (United Kingdom)

The dorsolateral reticular formation of the caudal medulla, the lateral tegmental field (LTF), participates in generating vomiting. LTF neurons exhibited complex responses to vestibular stimulation in decerebrate cats, indicating that they received converging inputs from a variety of labyrinthine receptors. Such a convergence pattern of vestibular inputs is appropriate for a brain region that participates in generating motion sickness. Since responses of brainstem neurons to vestibular stimulation can differ between decerebrate and conscious animals, the current study examined the effects of whole-body rotations in vertical planes on the activity of LTF neurons in conscious felines. Wobble stimuli, fixed-amplitude tilts, the direction of which moves around the animal at a constant speed, were used to determine the response vector orientation, and also to ascertain whether neurons had spatial-temporal convergence (STC) behavior (which is due to the convergence of vestibular inputs with different spatial and temporal properties). The proportion of LTF neurons with STC behavior in conscious animals (25 %) was similar to that in decerebrate cats. Far fewer neurons in other regions of the feline brainstem had STC behavior, confirming findings that many LTF neurons receive converging inputs from a variety of labyrinthine receptors. However, responses to vertical plane vestibular stimulation were considerably different in decerebrate and conscious felines for LTF neurons lacking STC behavior. In decerebrate cats, most LTF neurons had graviceptive responses to rotations, similar to those of otolith organ afferents. However, in conscious animals, the response properties were similar to those of semicircular canal afferents. These differences show that higher centers of the brain that are removed during decerebration regulate the labyrinthine inputs relayed to the LTF, either by gating connections in the brainstem or by conveying vestibular inputs directly to the region.

McCall AA; Moy JD; DeMayo WM; Puterbaugh SR; Miller DJ; Catanzaro MF; Yates BJ

2013-03-01

123

Processing of vestibular inputs by the medullary lateral tegmental field of conscious cats: implications for generation of motion sickness.  

Science.gov (United States)

The dorsolateral reticular formation of the caudal medulla, the lateral tegmental field (LTF), participates in generating vomiting. LTF neurons exhibited complex responses to vestibular stimulation in decerebrate cats, indicating that they received converging inputs from a variety of labyrinthine receptors. Such a convergence pattern of vestibular inputs is appropriate for a brain region that participates in generating motion sickness. Since responses of brainstem neurons to vestibular stimulation can differ between decerebrate and conscious animals, the current study examined the effects of whole-body rotations in vertical planes on the activity of LTF neurons in conscious felines. Wobble stimuli, fixed-amplitude tilts, the direction of which moves around the animal at a constant speed, were used to determine the response vector orientation, and also to ascertain whether neurons had spatial-temporal convergence (STC) behavior (which is due to the convergence of vestibular inputs with different spatial and temporal properties). The proportion of LTF neurons with STC behavior in conscious animals (25 %) was similar to that in decerebrate cats. Far fewer neurons in other regions of the feline brainstem had STC behavior, confirming findings that many LTF neurons receive converging inputs from a variety of labyrinthine receptors. However, responses to vertical plane vestibular stimulation were considerably different in decerebrate and conscious felines for LTF neurons lacking STC behavior. In decerebrate cats, most LTF neurons had graviceptive responses to rotations, similar to those of otolith organ afferents. However, in conscious animals, the response properties were similar to those of semicircular canal afferents. These differences show that higher centers of the brain that are removed during decerebration regulate the labyrinthine inputs relayed to the LTF, either by gating connections in the brainstem or by conveying vestibular inputs directly to the region. PMID:23274644

McCall, Andrew A; Moy, Jennifer D; DeMayo, William M; Puterbaugh, Sonya R; Miller, Daniel J; Catanzaro, Michael F; Yates, Bill J

2012-12-29

124

Vestibular modulation of spatial perception.  

Science.gov (United States)

Vestibular inputs make a key contribution to the sense of one's own spatial location. While the effects of vestibular stimulation on visuo-spatial processing in neurological patients have been extensively described, the normal contribution of vestibular inputs to spatial perception remains unclear. To address this issue, we used a line bisection task to investigate the effects of galvanic vestibular stimulation (GVS) on spatial perception, and on the transition between near and far space. Brief left-anodal and right-cathodal GVS or right-anodal and left-cathodal GVS were delivered. A sham stimulation condition was also included. Participants bisected lines of different lengths at six distances from the body using a laser pointer. Consistent with previous results, our data showed an overall shift in the bisection bias from left to right as viewing distance increased. This pattern suggests leftward bias in near space, and rightward bias in far space. GVS induced strong polarity dependent effects in spatial perception, broadly consistent with those previously reported in patients: left-anodal and right-cathodal GVS induced a leftward bisection bias, while right-anodal and left-cathodal GVS reversed this effect, and produced bisection bias toward the right side of the space. Interestingly, the effects of GVS were comparable in near and far space. We speculate that vestibular-induced biases in space perception may optimize gathering of information from different parts of the environment. PMID:24133440

Ferrè, Elisa R; Longo, Matthew R; Fiori, Federico; Haggard, Patrick

2013-10-10

125

Components of vestibular cortical function.  

UK PubMed Central (United Kingdom)

It is known that the functional response (e.g., nystagmus) to caloric vestibular stimulation is delayed and prolonged compared with the stimulus-response timing of other sensory systems. Imaging studies have used different models to predict cortical responses and to determine the areas of the brain that are involved. These studies have revealed a widespread network of vestibular brain regions. However, there is some disagreement regarding the brain areas involved, which may partly be caused by differences in the models used. This disagreement indicates the possible existence of multiple cortical components with different temporal characteristics that underlie cortical vestibular processing. However, data-driven methods have yet to be used to analyze the underlying hemodynamic components during and after vestibular stimulation. We performed functional magnetic resonance imaging (fMRI) on 12 healthy subjects during caloric stimulation and analyzed these data using a model-free analysis method (ICA). We found seven independent stimulus-induced components that outline a robust pattern of cortical activation and deactivation. These independent components demonstrated significant differences in their time courses. No single-modeled response function was able to cover the entire range of these independent components. The response functions determined in the present study should improve model-based studies investigating vestibular cortical processing.

Klingner CM; Volk GF; Flatz C; Brodoehl S; Dieterich M; Witte OW; Guntinas-Lichius O

2013-01-01

126

Compensation following bilateral vestibular damage.  

Science.gov (United States)

Bilateral loss of vestibular inputs affects far fewer patients than unilateral inner ear damage, and thus has been understudied. In both animal subjects and human patients, bilateral vestibular hypofunction (BVH) produces a variety of clinical problems, including impaired balance control, inability to maintain stable blood pressure during postural changes, difficulty in visual targeting of images, and disturbances in spatial memory and navigational performance. Experiments in animals have shown that non-labyrinthine inputs to the vestibular nuclei are rapidly amplified following the onset of BVH, which may explain the recovery of postural stability and orthostatic tolerance that occurs within 10?days. However, the loss of the vestibulo-ocular reflex and degraded spatial cognition appear to be permanent in animals with BVH. Current concepts of the compensatory mechanisms in humans with BVH are largely inferential, as there is a lack of data from patients early in the disease process. Translation of animal studies of compensation for BVH into therapeutic strategies and subsequent application in the clinic is the most likely route to improve treatment. In addition to physical therapy, two types of prosthetic devices have been proposed to treat individuals with bilateral loss of vestibular inputs: those that provide tactile stimulation to indicate body position in space, and those that deliver electrical stimuli to branches of the vestibular nerve in accordance with head movements. The relative efficacy of these two treatment paradigms, and whether they can be combined to facilitate recovery, is yet to be ascertained. PMID:22207864

McCall, Andrew A; Yates, Bill J

2011-12-27

127

Compensation following bilateral vestibular damage.  

UK PubMed Central (United Kingdom)

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

McCall AA; Yates BJ

2011-01-01

128

Reabilitação vestibular: tendências e indicações  

Directory of Open Access Journals (Sweden)

Full Text Available A reabilitação vestibular classicamente indicada no tratamento das disfunções do aparelho vestibular vem sendo cada vez mais prescrita para pessoas com outras problemáticas relacionadas ao equilíbrio e a orientação espacial. Este estudo de cunho bibliográfico teve por objetivo realizar uma síntese dos estudos com reabilitação vestibular, focados em outras morbidades além das vestibulopatias, indicando as tendências de investigações e os principais resultados, principalmente de intervenções, em diferentes situações. Para isso foi realizado um mapeamento dos estudos relacionados ao tema nas bases de dados Lilacs, Science Direct e Scielo sendo selecionados 13 artigos para análise. Os estudos encontrados utilizaram a reabilitação vestibular no tratamento de diferentes problemas de origem neuro-motora e psicológica. A reabilitação vestibular mostrou-se efetiva para morbidades como o Parkinson, a ansiedade e a depressão. Além disso, esteve associada a melhorias na qualidade de vida nos aspectos físico, emocional e funcional e, principalmente, à melhoria dos equilíbrios estático e dinâmico bem como à diminuição das quedas.

Clarissa Stefani Teixeira; Érico Felden Pereira; Angela Garcia Rossi; Luciane Sanchotene Etchepare Daronco

2010-01-01

129

Vestibular and balance treatment of the concussed athlete.  

UK PubMed Central (United Kingdom)

OBJECTIVES: The purpose of this chapter is to provide an update on the clinical management of vestibular and balance dysfunction in a concussed athlete with a focus on diagnosis, initial work-up, and initial and continuing management. Although much is still unknown about the etiology of vestibular and balance dysfunction in a concussed athlete, we briefly review current theories about neural pathophysiology to help link proposed treatment methodologies. INTRODUCTION: The treatment and management of vestibular and balance dysfunction in concussed athletes requires a multidisciplinary approach and is based on continuous reassessment of the presenting symptoms. The clinical challenge toward managing persistent symptoms of the post-concussive athlete is discerning whether a set of symptoms match diagnostic testing and whether further neurological work up is necessary. Because there are no discrete time boundaries to make such judgment calls, we offer a guide to help with the difficult clinical decisions necessary to treat the post-concussive athlete. METHODS: Literature search was performed using the following keywords: Vestibular and balance dysfunction, concussion, concussed athlete and treatment, vestibular rehabilitation therapy. Original research studies, literature reviews, and clinical guidelines were reviewed between 1997 and 2012, with the majority of articles dating beyond 2004. Although we acknowledge that post-concussive states lie within a continuum, we decided to divide treatment and management into three stages: time after initial impact, recovery, and prolonged recovery. RESULTS: In post-concussive athletes, impairments in balance may exist as a result of transmitted force to peripheral and central neural substrates that integrate sensory information and coordinate motor function. Corroborative information, clinical examination, neuropsychological testing, and continual reassessment are means to determine severity of dysfunction and track clinical course and resolution of symptoms. Persistence of symptoms beyond initial impact may require medication trials or adjustments that are tailored to the patient's medical history and/or neurocognitive rehabilitative techniques such as vestibular rehabilitation therapy to prevent progression of neurologic sequelae. Prolonged recovery of more than six months may require neurological consultation. CONCLUSION: Concussion management and treatment of vestibular and balance impairments in athletes should be assessed in a stepwise manner, from initial impact to resolution of symptoms. If symptoms are prolonged, impaired neuronal mechanisms or irreversible cerebral damage may underlie persistent symptoms and cognitive deficits seen in neurocognitive testing. Management protocols are currently focused on individualized assessment of neurocognitive assessment and comprehensive symptomatic evaluation (Reddy et al., 2008). It is widely accepted that neurocognitive and resolution of concussion-induced symptoms must be resolved prior to returning to sport or play and therefore, the athlete should be reassessed and treated until symptoms resolved.

Aligene K; Lin E

2013-01-01

130

Vestibular and pulse-related modulation of skin sympathetic nerve activity during sinusoidal galvanic vestibular stimulation in human subjects.  

UK PubMed Central (United Kingdom)

We have previously shown that sinusoidal galvanic vestibular stimulation (sGVS), a means of a selectively modulating vestibular afferent input without affecting other inputs, can cause partial entrainment of muscle sympathetic nerve activity (MSNA). Given that motion sickness causes sweating and pallor, we tested the hypothesis that sGVS also entrains skin sympathetic nerve activity (SSNA), but that the optimal frequencies are closer to those associated with slow postural changes (0.2 Hz). SSNA was recorded via tungsten microelectrodes inserted into the common peroneal nerve in 11 awake-seated subjects. Bipolar binaural sinusoidal GVS (+/-2 mA, 200 cycles) was applied to the mastoid processes at frequencies of 0.2, 0.5, 0.8, 1.1, 1.4, 1.7 and 2.0 Hz. All subjects reported strong postural illusions of 'rocking in a boat' or 'swaying in a hammock'. Sinusoidal GVS caused a marked entrainment of SSNA at all frequencies. Measured as the modulation index, vestibular modulation ranged from 81.5 +/- 4.0% at 0.2 Hz to 76.6 +/- 3.6% at 1.7 Hz; it was significantly weaker at 2.0 Hz (63.2 +/- 5.4%). Interestingly, pulse-related modulation of SSNA, which is normally weak, increased significantly during sGVS but was stronger at 0.8 Hz (86.2 +/- 2.0%) than at 0.2 Hz (69.3 +/- 8.3%), the opposite of the pattern seen with vestibular modulation of MSNA. We conclude that vestibular inputs can entrain the firing of cutaneous sympathetic neurones and increase their normally weak pulse-related rhythmicity.

James C; Stathis A; Macefield VG

2010-04-01

131

The use of antiserotonin drugs in the nucleoreticular vestibular syndrome: preliminary observations.  

UK PubMed Central (United Kingdom)

Vestibular neuronitis was described in 1949 and 1952 by Dix and Hallpike. Two groups of patients were described, those with sudden seizures and sensations of blackout (since identified as having vestibular neuritis) and a second group with symptoms of disequilibrium and feelings of top-heaviness or imbalance. The pathology was believed to be central to the inner ear. Arslan labeled these groups as having nucleoreticular vestibular syndrome. Using a suprathreshold stapedial reflex test, Bosatra localized the pathophysiology in the brainstem, an area rich in serotonergic neurons. This author has used antiserotonergic drugs, with success, in treating patients having the symptoms identified by Dix and Hallpike in their second group (which now should be labeled nucleoreticular vestibular syndrome), properly identified as a brainstem affliction. This study describes the characteristics of this disorder, the methods of diagnosis and treatment, and the outcomes in two groups of patients studied. The study concluded that antiserotonin drugs, specifically affecting 5-hydroxytryptamine2, should be considered in the management of nucleoreticular vestibular syndrome.

Lehrer JF

2004-01-01

132

Dual task interference during gait in patients with unilateral vestibular disorders  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Vestibular patients show slower and unsteady gait; they have also been shown to need greater cognitive resources when carrying out balance and cognitive dual tasks (DT). This study investigated DT interference during gait in a middle-aged group of subjects with dizziness and unsteadiness after unilateral vestibular neuronitis and in a healthy control group. Methods Fourteen individuals with subacute unilateral vestibular impairment after neuronitis and seventeen healthy subjects performed gait and cognitive tasks in single and DT conditions. A statistical gait analysis system was used and spatio-temporal parameters were considered. The cognitive task, consisting of backward counting by three, was tape recorded and the number of right figures was then calculated. Results Both patients and controls showed a more conservative gait during DT and between groups significant differences were not found. A significant decrease in cognitive performance during DT was found only in the vestibular group. Conclusions Results suggest that less attentional resources are available during gait in vestibular patients compared to controls, and that a priority is given in keeping up the motor task to the detriment of a decrease of the cognitive performance during DT.

Nascimbeni Alberto; Gaffuri Andrea; Penno Arminio; Tavoni Mara

2010-01-01

133

The Vestibular Implant: Quo Vadis?  

Science.gov (United States)

Objective: To assess the progress of the development of the vestibular implant (VI) and its feasibility short-term. Data sources: A search was performed in Pubmed, Medline, and Embase. Key words used were “vestibular prosth*” and “VI.” 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 VI and related topics were included and evaluated by two reviewers. No study was excluded since every study investigated different aspects of the VI. 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 VI 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.

van de Berg, Raymond; Guinand, Nils; Stokroos, Robert J.; Guyot, Jean-Philippe; Kingma, Herman

2011-01-01

134

Effects of gentamicin on guinea pig vestibular ganglion function and on substance P and neuropeptide Y.  

UK PubMed Central (United Kingdom)

Previous studies have demonstrated that following intratympanic gentamicin application in the guinea pigs, vestibular evoked myogenic potentials (VEMPs) were absent regardless of stimulation mode using either air-conducted sound (ACS) stimuli or galvanic vestibular stimulation (GVS). Ultrastructurally, both type I hair cells and their calyx terminals were distorted in the saccular macula. However, little is known about the toxic effects of gentamicin on the vestibular ganglion (VG). In this study, absent ACS- and GVS-VEMPs were noted in all the gentamicin-treated ears (100%), which were confirmed by the substantial loss of sensory hair cells in the saccular macula. Moreover, dramatic up-regulation of growth associated protein-43 (GAP-43) expression was detected in the ipsilateral VG neurons. The mean percentage of substance P-like immunoreactive (SP-LI) neurons in the treated VG (81.8±1.9%) was significantly higher than that in the control VG (68.6±3.3%). Conversely, the mean percentage of neuropeptide Y-like immunoreactive (NPY-LI) neurons in the treated VG (13.7±3.8%) was dramatically lower than that in the control VG (49.0±3.8%). Double labeling results shown 82% of SP-LI and 16% of NPY-LI neurons coexpressed with GAP-43, suggested that SP accumulating coincided with NPY decreasing in regenerating VG neurons after gentamicin treatment. Overall, the changes in SP and NPY expression in VG neurons after gentamicin treatment were like to those in the superior cervical ganglion following sympathectomy.

Lin CT; Young YH; Cheng PW; Lue JH

2010-12-01

135

'PREHAB': Vestibular prehabilitation to ameliorate the effect of a sudden vestibular loss.  

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A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote compensation and the symptoms subside. As the compensatory process requir...

Magnusson, Måns; Karlberg, Mikael; Tjernström, Fredrik

136

How vestibular stimulation interacts with illusory hand ownership  

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Artificial stimulation of the peripheral vestibular system has been shown to improve ownership of body parts in neurological patients, suggesting vestibular contributions to bodily self-consciousness. Here, we investigated whether galvanic vestibular stimulation (GVS) interferes with the mechanisms ...

Lopez, Christophe; Lenggenhager, Bigna; Blanke, Olaf

137

Vestibular Function and Quality of Life in Vestibular Schwannoma: Does Size Matter?  

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Objectives: Patients with vestibular schwannoma (VS) frequently suffer from disabling vestibular symptoms. This prospective follow-up study evaluates vestibular and auditory function and impairment of quality of life due to vertigo, dizziness, and imbalance in patients with unilateral VS of differen...

Wagner, Judith Nastjenka; Glaser, Miriam; Wowra, Berndt; Muacevic, Alexander; Goldbrunner, Roland; Cnyrim, Christian

138

Effects of visceral inputs on the processing of labyrinthine signals by the inferior and caudal medial vestibular nuclei: ramifications for the production of motion sickness.  

UK PubMed Central (United Kingdom)

Neurons located in the caudal aspect of the vestibular nucleus complex have been shown to receive visceral inputs and project to brainstem regions that participate in generating emesis, such as nucleus tractus solitarius and the "vomiting region" in the lateral tegmental field (LTF). Consequently, it has been hypothesized that neurons in the caudal vestibular nuclei participate in triggering motion sickness and that visceral inputs to the vestibular nucleus complex can affect motion sickness susceptibility. To obtain supporting evidence for this hypothesis, we determined the effects of intragastric infusion of copper sulfate (CuSO4) on responses of neurons in the inferior and caudal medial vestibular nuclei to rotations in vertical planes. CuSO4 readily elicits nausea and emesis by activating gastrointestinal (GI) afferents. Infusion of CuSO4 produced a >30 % change in spontaneous firing rate of approximately one-third of neurons in the caudal aspect of the vestibular nucleus complex. These changes in firing rate developed over several minutes, presumably in tandem with the emetic response. The gains of responses to vertical vestibular stimulation of a larger fraction (approximately two-thirds) of caudal vestibular nucleus neurons were altered over 30 % by administration of CuSO4. The response gains of some units went up, and others went down, and there was no significant relationship with concurrent spontaneous firing rate change. These findings support the notion that the effects of visceral inputs on motion sickness susceptibility are mediated in part through the caudal vestibular nuclei. However, our previous studies showed that infusion of CuSO4 produced larger changes in response to vestibular stimulation of LTF neurons, as well as parabrachial nucleus neurons that are believed to participate in generating nausea. Thus, integrative effects of GI inputs on the processing of labyrinthine inputs must occur at brain sites that participate in eliciting motion sickness in addition to the caudal vestibular nuclei. It seems likely that the occurrence of motion sickness requires converging inputs to brain areas that generate nausea and vomiting from a variety of regions that process vestibular signals.

Arshian MS; Puterbaugh SR; Miller DJ; Catanzaro MF; Hobson CE; McCall AA; Yates BJ

2013-07-01

139

Effects of visceral inputs on the processing of labyrinthine signals by the inferior and caudal medial vestibular nuclei: ramifications for the production of motion sickness.  

Science.gov (United States)

Neurons located in the caudal aspect of the vestibular nucleus complex have been shown to receive visceral inputs and project to brainstem regions that participate in generating emesis, such as nucleus tractus solitarius and the "vomiting region" in the lateral tegmental field (LTF). Consequently, it has been hypothesized that neurons in the caudal vestibular nuclei participate in triggering motion sickness and that visceral inputs to the vestibular nucleus complex can affect motion sickness susceptibility. To obtain supporting evidence for this hypothesis, we determined the effects of intragastric infusion of copper sulfate (CuSO4) on responses of neurons in the inferior and caudal medial vestibular nuclei to rotations in vertical planes. CuSO4 readily elicits nausea and emesis by activating gastrointestinal (GI) afferents. Infusion of CuSO4 produced a >30 % change in spontaneous firing rate of approximately one-third of neurons in the caudal aspect of the vestibular nucleus complex. These changes in firing rate developed over several minutes, presumably in tandem with the emetic response. The gains of responses to vertical vestibular stimulation of a larger fraction (approximately two-thirds) of caudal vestibular nucleus neurons were altered over 30 % by administration of CuSO4. The response gains of some units went up, and others went down, and there was no significant relationship with concurrent spontaneous firing rate change. These findings support the notion that the effects of visceral inputs on motion sickness susceptibility are mediated in part through the caudal vestibular nuclei. However, our previous studies showed that infusion of CuSO4 produced larger changes in response to vestibular stimulation of LTF neurons, as well as parabrachial nucleus neurons that are believed to participate in generating nausea. Thus, integrative effects of GI inputs on the processing of labyrinthine inputs must occur at brain sites that participate in eliciting motion sickness in addition to the caudal vestibular nuclei. It seems likely that the occurrence of motion sickness requires converging inputs to brain areas that generate nausea and vomiting from a variety of regions that process vestibular signals. PMID:23712685

Arshian, Milad S; Puterbaugh, Sonya R; Miller, Daniel J; Catanzaro, Michael F; Hobson, Candace E; McCall, Andrew A; Yates, Bill J

2013-05-28

140

Reabilitação vestibular na criança: estudo preliminar  

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Full Text Available Forma de estudo: Clínico prospectivo. Objetivo: O estudo analisa prospectivamente os resultados da Reabilitação Vestibular pelo método de Cawtorne & Cooksey em 22 crianças, portadoras de vestibulopatia periférica, associada ou não a sintomas centrais, com idade média de 8,6 anos. Material e método: Os exames quantitativos da função vestibular utilizados para quantificar a vestibulopatia foram a eletronistagmografia e a prova rotatória pendular decrescente (PRPD), mas a história clínica altamente sugestiva de processo vestibular foi considerada diagnóstica mesmo na presença de exames normais. Resultado: Os resultados apontam a Reabilitação Vestibular como uma opção válida no tratamento das vestibulopatias na infância, uma vez que não houve casos não responsivos ao tratamento.

Bittar Roseli S. M.; Pedalini Maria E. B; Medeiros Ítalo R. T.; Bottino Marco A.; Bento Ricardo F.

2002-01-01

 
 
 
 
141

Cranial Nerve VIII: Hearing and Vestibular Functions  

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Cranial nerve VIII brings sound and information about one's position and movement in space into the brain. The auditory and vestibular systems subserve several functions basic to clinical medicine and to psychiatry. This article covers the basics of cranial nerve VIII, hearing and vestibular systems...

Sanders, Richard D; Gillig, Paulette Marie

142

Insular strokes cause no vestibular deficits.  

UK PubMed Central (United Kingdom)

BACKGROUND AND PURPOSE: In previous imaging studies, the posterior insular cortex (IC) was identified as an essential part for vestibular otolith perception and considered as a core region of a human vestibular cortical network. However, it is still unknown whether lesions exclusively restricted to the posterior IC suffice to provoke signs of vestibular otolith dysfunction. Thus, present data aimed to test whether patients with lesions restricted to the IC showed vestibular otolith dysfunction. METHODS: We studied 10 acute unilateral stroke patients with lesions restricted to the IC which were tested for signs of vestibular otolith dysfunction, such as tilts of subjective visual vertical, out of 475 stroke patients. RESULTS: None of the patients was with stroke exclusively affecting the IC-specified vertigo as a symptom. In addition, neither showed a deficit in the perception of verticality (subjective visual vertical tilts) nor showed any further vestibular otolith deficits, such as ocular torsion or skew deviation. CONCLUSIONS: It seems that lesions of the posterior IC might have to be combined with lesions of adjacent regions of the cortical and subcortical vestibular network to cause vestibular otolith deficits.

Baier B; Conrad J; Zu Eulenburg P; Best C; Müller-Forell W; Birklein F; Dieterich M

2013-09-01

143

Vestibular schwannoma: role of conservative management  

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Objective: To assess the outcome of conservative management of vestibular schwannoma.Study design: Observational study. Setting: Tertiary referral centre.Patients: Four hundred and thirty-six patients with vestibular schwannoma (490 tumours), including 327 sporadic tumours and 163 tumours in 109 pat...

Suryanarayanan, R; Ramsden, RT; Saeed, SR; Aggarwal, R; King, AT; Rutherford, SA; Evans, DG; Gillespie, JE

144

Functional expression of TRPV1 and TRPA1 in rat vestibular ganglia.  

Science.gov (United States)

Both TRPV1 and TRPA1 are non-selective cation channels. They are co-expressed, and interact in sensory neurons such as dorsal root ganglia (DRG) and trigeminal ganglia (TG), and are involved in nociception, being activated by nociceptive stimuli. Immunohistological localization of TRPV1 in vestibular ganglion (VG) neurons has been reported. Although TRPA1 is co-expressed with TRPV1 in DRG and TG neurons, it is unclear whether TRPA1 channels are expressed in VG neurons. Moreover, it is unknown whether TRPV1 and TRPA1 channels are functional in VG neurons. We investigated the expression of TRPV1 and TRPA1 in rat VG neurons by RT-PCR, in situ hybridization, immunohistochemistry, and Ca(2+) imaging experiments. Both TRPV1 and TRPA1 RT-PCR products were amplified from the mRNA of rat VG neurons. In situ hybridization experiments showed TRPV1 and TRPA1 mRNA expression in the majority of VG neurons. Immunohistochemistry experiments confirmed TRPV1 protein expression. In Ca(2+) imaging experiments, capsaicin, a TRPV1 agonist, induced a significant increase in intracellular calcium ion concentration ([Ca(2+)]i) in rat primary cultured VG neurons, which was almost completely blocked by capsazepine, a TRPV1-specific antagonist. Cinnamaldehyde, a TRPA1 agonist, also caused an increase in [Ca(2+)]i, which was completely inhibited by HC030031, a TRPA1-specific antagonist. Moreover, in some VG neurons, a [Ca(2+)]i increase was evoked by both capsaicin and cinnamaldehyde in the same neuron. In summary, our histological and physiological studies reveal that TRPV1 and TRPA1 are expressed in VG neurons. It is suggested that TRPV1 and TRPA1 in VG neurons might participate in vestibular function and/or dysfunction such as vertigo. PMID:23916509

Kamakura, Takefumi; Ishida, Yusuke; Nakamura, Yukiko; Yamada, Takahiro; Kitahara, Tadashi; Takimoto, Yasumitsu; Horii, Arata; Uno, Atsuhiko; Imai, Takao; Okazaki, Suzuyo; Inohara, Hidenori; Shimada, Shoichi

2013-08-03

145

Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection  

Science.gov (United States)

Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

Edelmann, E.; Anken, R. H.; Rahmann, H.

2004-01-01

146

GABA, glycine, aspartate, glutamate and taurine in the vestibular nuclei: an immunocytochemical investigation in the cat.  

Science.gov (United States)

The distributions of five amino acids with well-established neuroexcitatory or neuroinhibitory properties were investigated in the feline vestibular complex. Consecutive semithin sections of plastic-embedded tissue were incubated with antisera raised against protein-glutaraldehyde conjugates of GABA, glycine, aspartate, glutamate and taurine. This approach allowed us to study the relative densities of the different immunoreactivities at the level of individual cell profiles. The results indicate that in the vestibular nuclei, neuronal colocalization of two or more neuroactive amino acids is the rule rather than an exception. Colocalization was found of immunoreactivities for GABA and glycine; glycine, aspartate and glutamate; glycine and aspartate, and glutamate and aspartate. GABA immunoreactive neurons were generally small and were found scattered throughout the vestibular complex. Glycine immunoreactive neurons were similarly distributed, except in the superior nucleus where the latter type of neuron could not be detected. Neuronal profiles colocalizing immunoreactivities for GABA and glycine occurred in all nuclei, but were most numerous in the lateral nucleus. The vast majority of the neurons showed noteworthy staining for glutamate and aspartate, although the level of immunoreactivities varied (e.g., the large neurons in the lateral and descending nuclei were more intensely aspartate immunoreactive than the smaller ones). Taurine-like immunoreactivity did not occur in neuronal cell bodies but appeared in Purkinje cell axons and in glial cell profiles. The functional significance of the complex pattern of amino acid colocalization remains to be clarified. In particular it needs to be distinguished between metabolic and transmitter pools of the different amino acids. The present results call for caution when attempts are made to conclude about transmitter identity on the basis of amino acid contents alone. PMID:1971225

Walberg, F; Ottersen, O P; Rinvik, E

1990-01-01

147

Reabilitação vestibular na criança: estudo preliminar Vestibular rehabilitation in children: preliminary study  

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Full Text Available Forma de estudo: Clínico prospectivo. Objetivo: O estudo analisa prospectivamente os resultados da Reabilitação Vestibular pelo método de Cawtorne & Cooksey em 22 crianças, portadoras de vestibulopatia periférica, associada ou não a sintomas centrais, com idade média de 8,6 anos. Material e método: Os exames quantitativos da função vestibular utilizados para quantificar a vestibulopatia foram a eletronistagmografia e a prova rotatória pendular decrescente (PRPD), mas a história clínica altamente sugestiva de processo vestibular foi considerada diagnóstica mesmo na presença de exames normais. Resultado: Os resultados apontam a Reabilitação Vestibular como uma opção válida no tratamento das vestibulopatias na infância, uma vez que não houve casos não responsivos ao tratamento.Study design: Clinical prospective. Aim: The authors analyze prospectively 22 children (mean age 8,6 years) with vestibulopathy treated with Vestibular Rehabilitation in order to verify its results. Material and methody: Twenty two children with peripheral vestibular disorders associated or not to central symptoms were submitted to vestibular stimulation by the method of Cawthorne & Cooksey. The methods used to quantify the vestibular abnormalities were the electronystagmography and rotational chair testing, but a suggestive history of vestibular disorder was accepted even the exams were normal. Results: All the patients improved and our results suggest that VR is a therapeutic alternative for the treatment of vestibular disorders in the children.

Roseli S. M. Bittar; Maria E. B Pedalini; Ítalo R. T. Medeiros; Marco A. Bottino; Ricardo F. Bento

2002-01-01

148

Reabilitação vestibular na criança: estudo preliminar/ Vestibular rehabilitation in children: preliminary study  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Forma de estudo: Clínico prospectivo. Objetivo: O estudo analisa prospectivamente os resultados da Reabilitação Vestibular pelo método de Cawtorne & Cooksey em 22 crianças, portadoras de vestibulopatia periférica, associada ou não a sintomas centrais, com idade média de 8,6 anos. Material e método: Os exames quantitativos da função vestibular utilizados para quantificar a vestibulopatia foram a eletronistagmografia e a prova rotatória pendular decrescente (PRP (more) D), mas a história clínica altamente sugestiva de processo vestibular foi considerada diagnóstica mesmo na presença de exames normais. Resultado: Os resultados apontam a Reabilitação Vestibular como uma opção válida no tratamento das vestibulopatias na infância, uma vez que não houve casos não responsivos ao tratamento. Abstract in english Study design: Clinical prospective. Aim: The authors analyze prospectively 22 children (mean age 8,6 years) with vestibulopathy treated with Vestibular Rehabilitation in order to verify its results. Material and methody: Twenty two children with peripheral vestibular disorders associated or not to central symptoms were submitted to vestibular stimulation by the method of Cawthorne & Cooksey. The methods used to quantify the vestibular abnormalities were the electronystagm (more) ography and rotational chair testing, but a suggestive history of vestibular disorder was accepted even the exams were normal. Results: All the patients improved and our results suggest that VR is a therapeutic alternative for the treatment of vestibular disorders in the children.

Bittar, Roseli S. M.; Pedalini, Maria E. B; Medeiros, Ítalo R. T.; Bottino, Marco A.; Bento, Ricardo F.

2002-08-01

149

Special (vestibular) training of servicemen  

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Full Text Available It has been shown that conditions of professional activity of airmobile servicemen require from them, in addition to excellent proficiency in military armament and materiel, high level of physical qualities and movement coordination development. It is essential to have high practice of vestibular apparatus, which helps to resist such negative feature as air sickness. The essences of term air sickness, its negative consequences for professional activity are highlighted. Possible tendencies of work in terms of enhancing organism resistance to air sickness (according to the analysis of publications and practical experience) are investigated.

Afonin V.M.

2011-01-01

150

Absence of short-term vestibular modulation of muscle sympathetic outflow, assessed by brief galvanic vestibular stimulation in awake human subjects.  

Science.gov (United States)

There is evidence in experimental animals for a potent vestibulosympathetic reflex, but its existence in humans is controversial. Static head-down neck flexion and off-vertical axis rotation have been shown to increase muscle sympathetic nerve activity (MSNA), but not skin sympathetic nerve activity (SSNA), whereas horizontal linear acceleration decreases MSNA in humans. However, both forms of stimuli also activate other receptors. To examine the effects of a pure vestibular stimulus on MSNA and SSNA, and its potential interaction with the baroreceptors, we used galvanic vestibular stimulation (GVS) in 12 healthy seated subjects. MSNA was recorded in ten subjects via a percutaneous microelectrode in the peroneal nerve; ECG, blood pressure, respiration, skin blood flow and sweating were also recorded. GVS (2 mA, 1 s pulse) was delivered via surface electrodes over the mastoid processes at unexpected times, triggered from the R-wave with a delay of 0, 200, 400 or 600 ms. In addition to causing robust postural illusions, GVS caused cutaneous vasoconstriction and sweat release in all subjects (due to a short-latency increase in SSNA, three subjects), but no significant change in MSNA. The failure of GVS to elicit a change in muscle sympathetic nerve activity, as documented by averaging, suggests that the vestibular system is not engaged in short-term modulation of muscle sympathetic activity. Conversely, phasic vestibular inputs do excite cutaneous sympathetic neurones, consistent with the observation that motion sickness is accompanied by pallor and sweating. PMID:14504857

Bolton, Philip S; Wardman, Daniel L; Macefield, Vaughan G

2003-09-18

151

Absence of short-term vestibular modulation of muscle sympathetic outflow, assessed by brief galvanic vestibular stimulation in awake human subjects.  

UK PubMed Central (United Kingdom)

There is evidence in experimental animals for a potent vestibulosympathetic reflex, but its existence in humans is controversial. Static head-down neck flexion and off-vertical axis rotation have been shown to increase muscle sympathetic nerve activity (MSNA), but not skin sympathetic nerve activity (SSNA), whereas horizontal linear acceleration decreases MSNA in humans. However, both forms of stimuli also activate other receptors. To examine the effects of a pure vestibular stimulus on MSNA and SSNA, and its potential interaction with the baroreceptors, we used galvanic vestibular stimulation (GVS) in 12 healthy seated subjects. MSNA was recorded in ten subjects via a percutaneous microelectrode in the peroneal nerve; ECG, blood pressure, respiration, skin blood flow and sweating were also recorded. GVS (2 mA, 1 s pulse) was delivered via surface electrodes over the mastoid processes at unexpected times, triggered from the R-wave with a delay of 0, 200, 400 or 600 ms. In addition to causing robust postural illusions, GVS caused cutaneous vasoconstriction and sweat release in all subjects (due to a short-latency increase in SSNA, three subjects), but no significant change in MSNA. The failure of GVS to elicit a change in muscle sympathetic nerve activity, as documented by averaging, suggests that the vestibular system is not engaged in short-term modulation of muscle sympathetic activity. Conversely, phasic vestibular inputs do excite cutaneous sympathetic neurones, consistent with the observation that motion sickness is accompanied by pallor and sweating.

Bolton PS; Wardman DL; Macefield VG

2004-01-01

152

Muscle responses and monosynaptic reflexes in falling monkey. Role of the vestibular system.  

UK PubMed Central (United Kingdom)

The free fall has been used in our laboratory as a way to test vestibular function in baboons in order to quantify vestibular compensation in the hemilabyrinthectomized animal. This study presents only those results that concern the contribution of the vestibular system to muscle responses due to sudden fall. EMG activity was recorded from the fully conscious animal using chronic electrodes implanted in various muscles. Spinal monosynaptic reflexes (Hoffmann's and tendon reflexes) were studied in the soleus muscle. Baboons were seated in a special chair suspended from an electromagnet and unexpectedly dropped 90 cm. Experiments were performed in normal, unilateral and bilateral vestibular neurectomized baboons. 1. In normal baboons, results showed a first short-latency response in all tested muscles, followed by a second peak of EMG activity in these muscles. Comparison with data from bilateral vestibular neurectomized baboons demonstrates that normal vestibular function is essential for the appearance of the first peak; the second peak rapidly disappears in our experimental situation where the animal's fall is mechanically braked and interrupted, so the animal does not have to make the postural adjustments necessary for landing, It is suggested that the first peak is concerned with the automatic and reflex control of landing, the second with the voluntary breaking of landing. 2. The modulation of monosynaptic spinal reflexes is closely related to the EMG response in soleus muscle. Facilitation of the H-reflex begins just prior to the onset of the EMG activity and continues as long as the baboon is falling. The T-reflex modulation presents a similar time course except in its early phase where it is depressed. Decrease in T and increase in H-reflexes suggest that the EMG response is most likely due to direct activation of alpha-motoneurons and not by means of the gamma-loop. 3. In unilateral vestibular neurectomized baboons, EMG and reflexological data show the classical asymmetry characterized by a strong decrease of the responses on the side of the lesion, and by a pronounced increase on the contralateral side. It is concluded that this represents the imbalance between the resting discharge of the vestibular neurons, and discloses the influence of labyrinthine afferences at the spinal level. We suggest consequently the use of EMG responses and modulation of spinal reflexes to fall in order to quantify vestibular compensation.

Lacour M; Xerri C; Hugon M

1978-01-01

153

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese 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, imitanciometri (more) a 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. Abstract in english 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. RESULT (more) S: a) from the 20 evaluated patients, 18 (90%) showed tinnitus complaint, 15 (75%) dizziness complaint and eight (40%) headache complaint; b) There was a prevalence of alterations in the caloric test and in the peripheral vestibular system; c) the results of the vestibular exam showed alterations in 14 patients (70%) being, eight cases (40%) of peripheral vestibular irritative syndromes and six cases (30%) of peripheral vestibular deficiency syndromes; d) we verified significant difference between the vestibular exam results and how long the patient had use the hearing aid; e) from the five patients that did not related vestibular symptoms four (80%) showed alterations in the vestibular exam. CONCLUSION: the importance and sensibility of the functional study regarding the balance system in this type of population must be emphasized because same disorders may occur in the vestibular exam in spite of symptom presence.

Paulin, Fabiane; Zeigelboim, Bianca Simone; Klagenberg, Karlin Fabianne; Rosa, Marine Raquel Diniz da

2009-01-01

154

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

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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 patients, 18 (90%) showed tinnitus complaint, 15 (75%) dizziness complaint and eight (40%) headache complaint; b) There was a prevalence of alterations in the caloric test and in the peripheral vestibular system; c) the results of the vestibular exam showed alterations in 14 patients (70%) being, eight cases (40%) of peripheral vestibular irritative syndromes and six cases (30%) of peripheral vestibular deficiency syndromes; d) we verified significant difference between the vestibular exam results and how long the patient had use the hearing aid; e) from the five patients that did not related vestibular symptoms four (80%) showed alterations in the vestibular exam. CONCLUSION: the importance and sensibility of the functional study regarding the balance system in this type of population must be emphasized because same disorders may occur in the vestibular exam in spite of symptom presence.

Fabiane Paulin; Bianca Simone Zeigelboim; Karlin Fabianne Klagenberg; Marine Raquel Diniz da Rosa

2009-01-01

155

Taste dysfunction in vestibular schwannomas  

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Full Text Available Background: Gustatory dysfunction associated with vestibular schwannomas (VS) is a poorly represented clinical presentation. Materials and Methods: One hundred and forty-nine cases operated from 1997 to 2005 where at least six-month follow-up was available were included. All patients were tested for taste sensations using four modalities of standard taste solutions. Apart from the taste sensations, any altered or abnormal taste perceptions were recorded both in the preoperative and postoperative period. Results: After applying the exclusion criteria, the taste dysfunction was studied in 142 patients. The evidence of decreased taste sensation was found in 58 (40.8%) patients prior to surgery. Preoperatively, taste disturbance was found in 29 (37.2%) giant, 28 (45.9%) large and one (33.3%) medium-sized tumors, respectively. There were no significant age or sex-related differences. The postoperative taste disturbances were found in 65 (45.8%) patients. Among patients with anatomically preserved facial nerve, postoperative taste disturbances were found in 55 (42.3%) patients whereas nine (6.9%) patients reported improvement in taste sensations. Conclusions: Taste dysfunction is common following vestibular schwannoma surgery. Patient counseling prior to surgery is necessary to avoid any distress caused by taste dysfunction. Taste dysfunction should be included in the facial nerve functional grading system while assessing outcome.

Sahu Rabi; Behari Sanjay; Agarwal Vimal; Giri Pramod; Jain Vijendra

2008-01-01

156

Rehabilitation after acute vestibular disorders.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To assess the efficacy of rehabilitation for dizzy patients after recent acute vestibular disturbance. METHODS: Forty patients recently hospitalised for an acute episode of rotational vertigo which lasted days were randomly divided into two groups. The first group (20 patients; group R) underwent active rehabilitation, while the second group (20 patients; group C) were told only to 'perform their daily activities'. Group R subjects underwent a total of 10 sessions of rehabilitation, including exercises on a stabilometric platform, point de mire and a series of five exercises repeated five times daily. All patients performed static stabilometry (posturography), undertook the dynamic gait index test, and completed a dizziness handicap questionnaire and a visual analogue scale for anxiety, at baseline and on completion. RESULTS: At 25 days, the rehabilitated patients obtained better results for all recorded outcomes, compared with the control group. The greatest difference in the rehabilitated subjects, compared with the control group, was for the dynamic gait index test; however, this difference was not statistically significant. The visual analogue scale anxiety score was statistically significantly more reduced in rehabilitated patients compared with control patients. Control patients maintained a higher visual dependence for postural control. CONCLUSIONS: These results would appear to support the effectiveness of a supervised exercise programme for patients following acute onset of vestibular disturbance. A correlation was found in both groups between dynamic gait index results and anxiety. In our experience, a rehabilitation programme seems to reduce dependence on visual cues for postural control.

Teggi R; Caldirola D; Fabiano B; Recanati P; Bussi M

2009-04-01

157

Vestibular stimulation attenuates unrealistic optimism.  

UK PubMed Central (United Kingdom)

INTRODUCTION: Unrealistic optimism refers to the pervasive tendency of healthy individuals to underestimate their likelihood of future misfortune, including illness. The phenomenon shares a qualitative resemblance with anosognosia, a neurological disorder characterized by a deficient appreciation of manifest current illness or impairment. Unrealistic optimism and anosognosia have been independently associated with a region of right inferior frontal gyrus, the pars opercularis. Moreover, anosognosia is temporarily abolished by vestibular stimulation, particularly by irrigation of the left (but not right) ear with cold water, a procedure known to activate the right inferior frontal region. We therefore hypothesized that left caloric stimulation would attenuate unrealistic optimism in healthy participants. METHODS: Thirty-one healthy right-handed adults underwent cold-water caloric vestibular stimulation of both ears in succession. During each stimulation episode, and at baseline, participants estimated their own relative risk of contracting a series of illnesses in the future. RESULTS: Compared to baseline, average risk estimates were significantly higher during left-ear stimulation, whereas they remained unchanged during right-ear stimulation. Unrealistic optimism was thus reduced selectively during cold caloric stimulation of the left ear. CONCLUSIONS: Our results point to a unitary mechanism underlying both anosognosia and unrealistic optimism, and suggest that unrealistic optimism is a form of subclinical anosognosia for prospective symptoms.

McKay R; Tamagni C; Palla A; Krummenacher P; Hegemann SC; Straumann D; Brugger P

2013-09-01

158

Cochlear implantation after selective vestibular nerve section.  

UK PubMed Central (United Kingdom)

INTRODUCTION: Vestibular nerve section is a highly effective procedure for the control of vertigo in patients with Ménière's disease. However, hearing loss is a possible complication. If hearing loss occurs after vestibular nerve section, magnetic resonance imaging should make it possible to establish the presence or absence of an intact cochlear nerve. METHOD: Case report and review of the world literature concerning cochlear implantation after vestibular nerve section. CASE REPORT: We present a patient who developed subtotal hearing loss after vestibular nerve section. Magnetic resonance imaging was used to verify the presence of an intact cochlear nerve, enabling successful cochlear implantation. CONCLUSION: To our knowledge, this is the first reported case of cochlear implantation carried out after selective vestibular nerve section. Given recent advances in cochlear implantation, this case indicates that it is essential to make every effort to spare the cochlear nerve if vestibular nerve section is required. If hearing loss occurs after vestibular nerve section, magnetic resonance imaging should be undertaken to establish whether the cochlear nerve is intact.

Martens C; Csillag A; Davies M; Fagan P

2013-03-01

159

Anatomy of the vestibular system: a review.  

UK PubMed Central (United Kingdom)

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

Khan S; Chang R

2013-01-01

160

[Identification of the vestibular projections in the oculomotor nuclei in the cat by autoradiography and electron microscopy  

UK PubMed Central (United Kingdom)

The projection of vestibular pathways to the oculomotor nuclei ws investigated by electron microscopic radioautography. Unilateral injection of tritiated amino acids into the rostral vestibular complex was used in order to characterize the location and to identify the different types of labeled synaptic terminals involved in these pathways. In the normal oculomotor nuclei, 4 types of synaptic boutons were identified. Following the labeling of the vestibular synapses, in the ipsilateral oculomotor nucleus, types I and II boutons are the most prominent group and make up 75% of the synaptic vesicles, they are distributed on the cellular soma and the large dendrites of the oculomotor neurons. In contrast, in the contralateral oculomotor nucleus, type III boutons which are smaller and have larger diameter synaptic vesicles were predominant; they are prevalent on the distal part of the dendritic tree. From the results obtained, a relationship between the present anatomical findings and previously published physiological studies is established. The following conclusion is suggested: the inhibitory vestibular inputs probably terminate on the oculomotor neurons by these large types I and II boutons and the excitatory vestibular inputs by the smaller type III boutons. Also discussed is the complexity of the pattern of afferentation and the functional arrangement of the oculomotor nuclei.

Demêmes D; Raymond J

1980-09-01

 
 
 
 
161

Vestibular PREHAB and gentamicin before schwannoma surgery may improve long-term postural function  

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Abstract Background: Unilateral vestibular deafferentation (uVD), as performed in vestibular schwannoma surgery, results in a chronic vestibular deficit, though most of the insufficiency can be compensated by other sensory input. By vestibular training (prehabituation) performed before surge...

162

Changes in Histamine Receptors (H1, H2, and H3) Expression in Rat Medial Vestibular Nucleus and Flocculus after Unilateral Labyrinthectomy: Histamine Receptors in Vestibular Compensation.  

UK PubMed Central (United Kingdom)

Vestibular compensation is the process of behavioral recovery following peripheral vestibular lesion. In clinics, the histaminergic medicine is the most widely prescribed for the treatment of vertigo and motion sickness, however, the molecular mechanisms by which histamine modulates vestibular function remain unclear. During recovery from the lesion, the modulation of histamine receptors in the medial vestibular nucleus (MVN) and the flocculus may play an important role. Here with the means of quantitative real-time PCR, western blotting and immunohistochemistry, we studied the expression of histamine receptors (H1, H2, and H3) in the bilateral MVN and the flocculus of rats on the 1st, 3rd, and 7th day following unilateral labyrinthectomy (UL). Our results have shown that on the ipsi-lesional flocculus the H1, H2 and H3 receptors mRNA and the protein increased significantly on the 1st and 3rd day, with compare of sham controls and as well the contralateral side of UL. However, on the 7th day after UL, this expression returned to basal levels. Furthermore, elevated mRNA and protein levels of H1, H2 and H3 receptors were observed in the ipsi-lesional MVN on the 1st day after UL compared with sham controls and as well the contralateral side of UL. However, this asymmetric expression was absent by the 3rd post-UL. Our findings suggest that the upregulation of histamine receptors in the MVN and the flocculus may contribute to rebalancing the spontaneous discharge in bilateral MVN neurons during vestibular compensation.

Zhou L; Zhou W; Zhang S; Liu B; Leng Y; Zhou R; Kong W

2013-01-01

163

Vestibular function assessment using the NIH Toolbox.  

UK PubMed Central (United Kingdom)

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

Rine RM; Schubert MC; Whitney SL; Roberts D; Redfern MS; Musolino MC; Roche JL; Steed DP; Corbin B; Lin CC; Marchetti GF; Beaumont J; Carey JP; Shepard NP; Jacobson GP; Wrisley DM; Hoffman HJ; Furman G; Slotkin J

2013-03-01

164

Vestibular Evoked Myogenic Potentials in Migraine Patients  

Directory of Open Access Journals (Sweden)

Full Text Available Background and Aim: Patients with migraine commonly show vestibular symptoms. However, abnormal neurotological test findings during the inter-attack intervals, even in the absence of vestibular symptoms, are suggestive of subclinical vestibular dysfunction in migraine. This study aimed to compare the vestibular evoked myogenic potentials between migraine patients and normal individuals.Methods: Subjects included 25 patients with migraine and 26 healthy volunteers with an age range of 20-53 years old. The vestibular evoked myogenic potentials were recorded with 500 Hz tone bursts at 95 dB nHL.Results: Mean of absolute amplitude and p13 latency values in the migraine group were significantly less and more than the normal group, respectively (p=0.001 for absolute amplitude in right and left ears; p=0.004 for p13 latency in right ears and p=0.02 in left ears). There was no statistically significant difference between the two groups in mean of the n23 latency and also the amplitude ratio (p>0.05).Conclusion: According to the prolonged latency of vestibular evoked myogenic potentials response, vestibulospinal tract in brainstem is probably involved in migraine patients. However, due to small sample size, for generalizing this result to all patients with migraine, further researches are needed.

Marziyeh Moallemi; Fahimeh Hajiabolhassan; Jamileh Fatahi; Roya Abolfazli; Shohre Jalaie; Fatemeh Khamseh

2011-01-01

165

Vestibular stimulation affects optic-flow sensitivity.  

UK PubMed Central (United Kingdom)

Typically, multiple cues can be used to generate a particular percept. Our area of interest is the extent to which humans are able to synergistically combine cues that are generated when moving through an environment. For example, movement through the environment leads to both visual (optic-flow) and vestibular stimulation, and studies have shown that non-human primates are able to combine these cues to generate a more accurate perception of heading than can be obtained with either cue in isolation. Here we investigate whether humans show a similar ability to synergistically combine optic-flow and vestibular cues. This was achieved by determining the sensitivity to optic-flow stimuli while physically moving the observer, and hence producing a vestibular signal, that was either consistent with the optic-flow signal, eg a radially expanding pattern coupled with forward motion, or inconsistent with it, eg a radially expanding pattern with backward motion. Results indicate that humans are more sensitive to motion-in-depth optic-flow stimuli when they are combined with complementary vestibular signals than when they are combined with conflicting vestibular signals. These results indicate that in humans, like in nonhuman primates, there is perceptual integration of visual and vestibular signals.

Edwards M; O'Mahony S; Ibbotson MR; Kohlhagen S

2010-01-01

166

Crystallisation pattern of vestibular mucus and its relation to vestibular electrical resistance in cycling sow.  

Science.gov (United States)

Changes in the genital mucus around the oestrus are used by different diagnostic methods to determine optimal fertilisation time. In the current study, the authors evaluated the different arborisation patterns found in vestibular mucus, and also established its relationship with vestibular resistance changes during oestrus. Thirty multiparous sows were checked by transrectal ultrasonography to determine ovulation time every 12 hours. Vestibular resistance was measured with a commercial resistance probe, and vestibular mucus ferning was also evaluated every 12 hours during the oestrus. Significant changes (P < 0.05) in vestibular resistance were detected, registering high variation among individuals. Maximum resistance data was reached between 12 and 24 hours after ovulation time in 83 per cent of the sows. Crystallisation samples were classified into three different patterns according to the fern-like crystal degree. Arborisation peak occurred from 48 to 36 hours before the moment of ovulation, when vestibular resistance values increased gradually. In the optimal insemination moment, vestibular resistance increased significantly (P < 0.05) and vestibular mucus showed a low crystallisation pattern (P < 0.05). Combining several methods to measure genital mucus changes may predict the ovulation time and the best insemination moment. PMID:22922708

Luño, V; Gil, L; Jerez, R A; Malo, C; Galé, I; de Blas, I

2012-08-24

167

Crystallisation pattern of vestibular mucus and its relation to vestibular electrical resistance in cycling sow.  

UK PubMed Central (United Kingdom)

Changes in the genital mucus around the oestrus are used by different diagnostic methods to determine optimal fertilisation time. In the current study, the authors evaluated the different arborisation patterns found in vestibular mucus, and also established its relationship with vestibular resistance changes during oestrus. Thirty multiparous sows were checked by transrectal ultrasonography to determine ovulation time every 12 hours. Vestibular resistance was measured with a commercial resistance probe, and vestibular mucus ferning was also evaluated every 12 hours during the oestrus. Significant changes (P < 0.05) in vestibular resistance were detected, registering high variation among individuals. Maximum resistance data was reached between 12 and 24 hours after ovulation time in 83 per cent of the sows. Crystallisation samples were classified into three different patterns according to the fern-like crystal degree. Arborisation peak occurred from 48 to 36 hours before the moment of ovulation, when vestibular resistance values increased gradually. In the optimal insemination moment, vestibular resistance increased significantly (P < 0.05) and vestibular mucus showed a low crystallisation pattern (P < 0.05). Combining several methods to measure genital mucus changes may predict the ovulation time and the best insemination moment.

Luño V; Gil L; Jerez RA; Malo C; Galé I; de Blas I

2012-09-01

168

Comparison of Interictal Vestibular Function in Vestibular Migraine vs Migraine Without Vertigo.  

UK PubMed Central (United Kingdom)

BACKGROUND: Patients with vestibular migraine (VM) suffer attacks of vertigo that often occur in isolation from headache attacks. We aimed to assess and compare vestibular function interictally in patients with VM and patients with migraine without vertigo (M). METHODS: Thirty-eight patients diagnosed with definite VM according to the Neuhauser criteria, and 32 patients diagnosed with M according to the International Headache Society criteria were examined between attacks using a broad battery of bedside vestibular tests, a caloric test, and videonystagmography. RESULTS: Overall, 70% of the VM patients and 34% of the M patients showed abnormalities on one or more of the 14 performed vestibular tests (P?=?.006). Abnormal findings were more frequent in VM than in M patients on Romberg's test, test for voluntary fixation suppression of the vestibular ocular reflex and test for static positional nystagmus (P?=?.03, .01 and .04, respectively). There were no differences in the distribution of central and peripheral vestibular signs between VM and M patients. CONCLUSIONS: Vestibular abnormalities were present interictally among both VM and M patients, but were found about twice as frequently among VM patients. This may indicate that subclinical vestibular dysfunction is an integral part of migraine pathology in general, and not solely in VM.

Boldingh MI; Ljøstad U; Mygland A; Monstad P

2013-07-01

169

Corticosteroids for the treatment of idiopathic acute vestibular dysfunction (vestibular neuritis).  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Idiopathic acute vestibular dysfunction (vestibular neuritis) is the second most common cause of peripheral vertigo after benign paroxysmal positional vertigo (BPPV) and accounts for 7% of the patients who present at outpatient clinics specialising in the treatment of dizziness. The exact aetiology ...

Fishman, JM; Burgess, C; Waddell, A

170

Schwannoma vestibular: involução tumoral espontânea Vestibular Schwannoma: spontaneous tumor involution  

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Full Text Available A história natural dos schwannomas vestibulares ainda não está totalmente elucidada, mas sua maioria tende a apresentar crescimento lento, muitos permanecendo sem sintomas durante toda a vida do paciente. Cerca de 69% deste tipo de tumor diagnosticados não apresentam crescimento e, destes, 16% chegam a apresentar regressão tumoral. Considerando os tumores que apresentam crescimento, cerca de 70% crescem menos de 2 mm ao ano. O avanço nos métodos de diagnóstico por imagem, particularmente à ressonância magnética com contraste de gadolínio, permite o diagnóstico cada vez mais de lesões com sintomas mínimos e tamanhos menores. O tratamento de escolha para estes tumores ainda é a ressecção completa do tumor. As técnicas cirúrgicas apresentaram grande avanço nas últimas décadas, o que possibilitou diminuição da mortalidade. Assim, a cirurgia, que antes tinha como objetivo apenas a ressecção completa do tumor, agora visa também à preservação da audição e da função do nervo facial. Considerações finais: Considerando-se sua história natural, abre-se a possibilidade de uma conduta conservadora já que o ritmo de crescimento no primeiro ano após o diagnóstico prediz o comportamento do tumor nos próximos anos. A conduta conservadora não implica em repúdio à cirurgia, devendo ser utilizada em casos de aumento tumoral, piora dos sintomas ou desejo do paciente. Além disso, em relatos de literatura não há diferença estatisticamente significante entre os pacientes submetidos à cirurgia logo após o diagnóstico ou após conduta conservadora inicial, no que diz respeito às seqüelas pós-operatórias.The natural history of Vestibular Schwannomas (VS) is yet not totally known, but most of them have the tendency to slow growth, sometimes without any kind of symptoms during the individual’s entire time. About 69% of diagnosed VS do not grow at all and 16% of these can even regress. Considering tumors that grow, about 70% have grown less than 2mm an year. Advanced radiological diagnosis, especially magnetic resonance imaging with gadolinium helps us diagnose small and less symptomatic tumors. Treatment of choice still is complete tumor resection. Surgical approaches have improved considerably and have helped preserve facial nerve function and hearing. Considering VS’s natural history, there is a possibility for conservative treatment for these tumors, because their growth in the first year after diagnosis predicts tumor growth behavior in the next years. Surgery should be done in cases of tumor growth, patient’s desire or symptoms worsening. Moreover, in terms of postoperative sequelae, there is no difference between patients who underwent surgery immediately after diagnosis and those who underwent initial conservative treatment for these tumors.

Norma de Oliveira Penido; Rodrigo P. Tangerina; Eduardo Macoto Kosugi; Carlos Eduardo Cesário de Abreu; Matheus Brandão Vasco

2007-01-01

171

Schwannoma vestibular: involução tumoral espontânea/ Vestibular Schwannoma: spontaneous tumor involution  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A história natural dos schwannomas vestibulares ainda não está totalmente elucidada, mas sua maioria tende a apresentar crescimento lento, muitos permanecendo sem sintomas durante toda a vida do paciente. Cerca de 69% deste tipo de tumor diagnosticados não apresentam crescimento e, destes, 16% chegam a apresentar regressão tumoral. Considerando os tumores que apresentam crescimento, cerca de 70% crescem menos de 2 mm ao ano. O avanço nos métodos de diagnóstico por (more) imagem, particularmente à ressonância magnética com contraste de gadolínio, permite o diagnóstico cada vez mais de lesões com sintomas mínimos e tamanhos menores. O tratamento de escolha para estes tumores ainda é a ressecção completa do tumor. As técnicas cirúrgicas apresentaram grande avanço nas últimas décadas, o que possibilitou diminuição da mortalidade. Assim, a cirurgia, que antes tinha como objetivo apenas a ressecção completa do tumor, agora visa também à preservação da audição e da função do nervo facial. Considerações finais: Considerando-se sua história natural, abre-se a possibilidade de uma conduta conservadora já que o ritmo de crescimento no primeiro ano após o diagnóstico prediz o comportamento do tumor nos próximos anos. A conduta conservadora não implica em repúdio à cirurgia, devendo ser utilizada em casos de aumento tumoral, piora dos sintomas ou desejo do paciente. Além disso, em relatos de literatura não há diferença estatisticamente significante entre os pacientes submetidos à cirurgia logo após o diagnóstico ou após conduta conservadora inicial, no que diz respeito às seqüelas pós-operatórias. Abstract in english The natural history of Vestibular Schwannomas (VS) is yet not totally known, but most of them have the tendency to slow growth, sometimes without any kind of symptoms during the individual?s entire time. About 69% of diagnosed VS do not grow at all and 16% of these can even regress. Considering tumors that grow, about 70% have grown less than 2mm an year. Advanced radiological diagnosis, especially magnetic resonance imaging with gadolinium helps us diagnose small and le (more) ss symptomatic tumors. Treatment of choice still is complete tumor resection. Surgical approaches have improved considerably and have helped preserve facial nerve function and hearing. Considering VS?s natural history, there is a possibility for conservative treatment for these tumors, because their growth in the first year after diagnosis predicts tumor growth behavior in the next years. Surgery should be done in cases of tumor growth, patient?s desire or symptoms worsening. Moreover, in terms of postoperative sequelae, there is no difference between patients who underwent surgery immediately after diagnosis and those who underwent initial conservative treatment for these tumors.

Penido, Norma de Oliveira; Tangerina, Rodrigo P.; Kosugi, Eduardo Macoto; Abreu, Carlos Eduardo Cesário de; Vasco, Matheus Brandão

2007-12-01

172

Reabilitação vestibular em idosos com tontura/ Vestibular rehabilitation in elderly patients with dizziness  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese TEMA: o envelhecimento populacional é um processo natural, manifesta-se por um declínio das funções de diversos órgãos. A reabilitação vestibular (RV) é um processo terapêutico que visa promover a redução significativa dos sintomas labirínticos. OBJETIVO: verificar os benefícios dos exercícios de RV por meio da avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) - adaptação brasileira. MÉTODO: participaram deste estudo (more) oito idosos com queixa de tontura, na faixa etária de 63 a 82 anos, três do sexo masculino e cinco do sexo feminino. Realizaram-se os seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular por meio da vectoeletronistagmografia (VENG), aplicação do questionário DHI e dos exercícios de RV de Cawthorne (1944) e Cooksey (1946). RESULTADOS: com relação as queixas auditivas e vestibulares, observou-se a incidência do zumbido, da hipoacusia, da vertigem postural e do desequilíbrio; na avaliação da função vestibular, constataram-se alterações em todos os idosos; as alterações foram na sua maioria na prova calórica com predomínio da hiporreflexia uni e bilateral; constataram-se, no exame vestibular, três casos de síndrome vestibular periférica deficitária unilateral, três casos de síndrome vestibular periférica deficitária bilateral, um caso de síndrome vestibular central deficitária bilateral e um caso de síndrome vestibular central irritativa bilateral; houve melhora significativa dos aspectos físico (p = 0,00413), funcional (p = 0,00006) e emocional (p = 0,03268) após a realização dos exercícios de RV. CONCLUSÃO: o protocolo utilizado de RV promoveu melhora na qualidade de vida dos idosos e auxiliou no processo de compensação vestibular. Abstract in english BACKGROND: the aging of the population is a natural process and is manifested by a decline in the functions of several organs. Vestibular rehabilitation (VR) is a therapeutic process that seeks to promote a significant reduction in the symptoms of the labyrinth. AIM: to verify the benefits of VR exercises through the application of the Dizziness Handicap Inventory (DHI) questionnaire - Brazilian version - pre and post rehabilitation. METHOD: participants of this study wer (more) e eight elderly patients with dizziness, ages between 63 and 82 years, three male and five female. The following procedures were carried out: medical history, otologic inspection, vestibular evaluation with vectoelectronystagmography (VENG), application of the DHI questionnaire and of the Cawthorne (1944) and Cooksey (1946) VR exercises. RESULTS: regarding the auditory and vestibular complaints which were referred to in the medical history, the following was observed: presence of tinnitus, hearing loss, postural vertigo and of unbalance. In the evaluation of the vestibular function alterations were observed for all of the participants, mainly in the caloric test, with a prevalence of unilateral and bilateral hypofunction. In the vestibular exam the following was observed: three cases of unilateral peripheral vestibular deficit syndrome, three cases of bilateral peripheral vestibular deficit syndrome, one case of bilateral central vestibular deficit syndrome and one case of irritating bilateral central vestibular syndrome. There was a statistically significant improvement of the following aspects after VR: physical (p=0.00413), functional (p=0.00006) and emotional (p=0.03268). CONCLUSION: the VR protocol favored the improvement of life quality of the participants and was of assistance in the process of vestibular compensation.

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

2007-06-01

173

Reabilitação vestibular em idosos com tontura Vestibular rehabilitation in elderly patients with dizziness  

Directory of Open Access Journals (Sweden)

Full Text Available TEMA: o envelhecimento populacional é um processo natural, manifesta-se por um declínio das funções de diversos órgãos. A reabilitação vestibular (RV) é um processo terapêutico que visa promover a redução significativa dos sintomas labirínticos. OBJETIVO: verificar os benefícios dos exercícios de RV por meio da avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) - adaptação brasileira. MÉTODO: participaram deste estudo oito idosos com queixa de tontura, na faixa etária de 63 a 82 anos, três do sexo masculino e cinco do sexo feminino. Realizaram-se os seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular por meio da vectoeletronistagmografia (VENG), aplicação do questionário DHI e dos exercícios de RV de Cawthorne (1944) e Cooksey (1946). RESULTADOS: com relação as queixas auditivas e vestibulares, observou-se a incidência do zumbido, da hipoacusia, da vertigem postural e do desequilíbrio; na avaliação da função vestibular, constataram-se alterações em todos os idosos; as alterações foram na sua maioria na prova calórica com predomínio da hiporreflexia uni e bilateral; constataram-se, no exame vestibular, três casos de síndrome vestibular periférica deficitária unilateral, três casos de síndrome vestibular periférica deficitária bilateral, um caso de síndrome vestibular central deficitária bilateral e um caso de síndrome vestibular central irritativa bilateral; houve melhora significativa dos aspectos físico (p = 0,00413), funcional (p = 0,00006) e emocional (p = 0,03268) após a realização dos exercícios de RV. CONCLUSÃO: o protocolo utilizado de RV promoveu melhora na qualidade de vida dos idosos e auxiliou no processo de compensação vestibular.BACKGROND: the aging of the population is a natural process and is manifested by a decline in the functions of several organs. Vestibular rehabilitation (VR) is a therapeutic process that seeks to promote a significant reduction in the symptoms of the labyrinth. AIM: to verify the benefits of VR exercises through the application of the Dizziness Handicap Inventory (DHI) questionnaire - Brazilian version - pre and post rehabilitation. METHOD: participants of this study were eight elderly patients with dizziness, ages between 63 and 82 years, three male and five female. The following procedures were carried out: medical history, otologic inspection, vestibular evaluation with vectoelectronystagmography (VENG), application of the DHI questionnaire and of the Cawthorne (1944) and Cooksey (1946) VR exercises. RESULTS: regarding the auditory and vestibular complaints which were referred to in the medical history, the following was observed: presence of tinnitus, hearing loss, postural vertigo and of unbalance. In the evaluation of the vestibular function alterations were observed for all of the participants, mainly in the caloric test, with a prevalence of unilateral and bilateral hypofunction. In the vestibular exam the following was observed: three cases of unilateral peripheral vestibular deficit syndrome, three cases of bilateral peripheral vestibular deficit syndrome, one case of bilateral central vestibular deficit syndrome and one case of irritating bilateral central vestibular syndrome. There was a statistically significant improvement of the following aspects after VR: physical (p=0.00413), functional (p=0.00006) and emotional (p=0.03268). CONCLUSION: the VR protocol favored the improvement of life quality of the participants and was of assistance in the process of vestibular compensation.

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

2007-01-01

174

Interactive Healthcare Systems in the Home: Vestibular Rehabilitation  

DEFF Research Database (Denmark)

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.

Aarhus, Rikke; Grönvall, Erik

2010-01-01

175

Neurohumoral Reactions to Long-Term Vestibular Stimulation in Man.  

Science.gov (United States)

Neuroendocrine metabolism regulation during vestibular stimulation studies in man are wide-spread in gravitational physiology and space medicine in the recent past. As a rule, these investigations are associated with vestibular stimulation for only severa...

I. A. Nichiporuk A. N. Rapotkov O. I. Orlov A. I. Grigoriev

1993-01-01

176

Arreflexia pós-calórica bilateral: aplicabilidade clínica da reabilitação vestibular Bilateral vestibular loss after caloric irrigation: clinical aplication of vestibular rehabilitation  

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Full Text Available A perda bilateral da função vestibular é rara em pacientes com vertigem e desequilíbrio, porém os sintomas muitas vezes são incapacitantes e seu tratamento é tema controverso na literatura. OBJETIVO: Nosso objetivo foi avaliar e descrever a resposta clínica de pacientes com distúrbio do equilíbrio corporal secundário à arreflexia vestibular pós-calórica bilateral, documentada pela eletronistagmografia, submetidos à Reabilitação Vestibular. FORMA DE ESTUDO: Retrospectivo, inclui um desenho de descrição de casos. MÉTODO: Foram avaliadas as respostas de 8 pacientes portadores de arreflexia pós-calórica bilateral submetidos à Reabilitação Vestibular, observando-se a relação entre os resultados de exame e sintomas pré e pós-tratamento. A avaliação da resposta clínica foi feita por meio de escala analógico-visual. RESULTADOS: Após a Reabilitação Vestibular, 7 (87,5%) dos 8 pacientes submetidos à terapia apresentaram melhora clínica. CONCLUSÃO: embora não seja esperada melhora completa do equilíbrio corporal, a Reabilitação Vestibular é uma terapia eficaz na recuperação desses pacientes.Bilateral vestibular loss is a rare diagnosis among patients with dizziness and imbalance. Nevertheless, symptoms are often disabling and therapy is yet to be establish. AIM: To evaluate and describe the clinical outcome of patients with imbalance due to bilateral vestibular loss after caloric test, treated with An analog visual scale was used to evaluated clinical results. Vestibular Rehabilitation. STUDY DESIGN: Retrospective case report. METHOD: Pre and post treatment outcomes were evaluated in 8 individuals suffering from post caloric bilateral vestibular paresis whose were submitted to vestibular rehabilitation. RESULTS: After Vestibular Rehabilitation, 7 (87,5%) of 8 patients had clinical improvement. CONCLUSION: Although is not expected entirely compensation for bilateral vestibular loss, the vestibular rehabilitation may be use as a therapeutic method for these patients.

Roseli Saraiva Moreira Bittar; Marco Aurélio Bottino; Maria Elisabete Bovino Pedalini; Jeanne da Rosa Oiticica Ramalho; Camila de Giacomo Carneiro

2004-01-01

177

Arreflexia pós-calórica bilateral: aplicabilidade clínica da reabilitação vestibular/ Bilateral vestibular loss after caloric irrigation: clinical aplication of vestibular rehabilitation  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A perda bilateral da função vestibular é rara em pacientes com vertigem e desequilíbrio, porém os sintomas muitas vezes são incapacitantes e seu tratamento é tema controverso na literatura. OBJETIVO: Nosso objetivo foi avaliar e descrever a resposta clínica de pacientes com distúrbio do equilíbrio corporal secundário à arreflexia vestibular pós-calórica bilateral, documentada pela eletronistagmografia, submetidos à Reabilitação Vestibular. FORMA DE ESTUDO (more) : Retrospectivo, inclui um desenho de descrição de casos. MÉTODO: Foram avaliadas as respostas de 8 pacientes portadores de arreflexia pós-calórica bilateral submetidos à Reabilitação Vestibular, observando-se a relação entre os resultados de exame e sintomas pré e pós-tratamento. A avaliação da resposta clínica foi feita por meio de escala analógico-visual. RESULTADOS: Após a Reabilitação Vestibular, 7 (87,5%) dos 8 pacientes submetidos à terapia apresentaram melhora clínica. CONCLUSÃO: embora não seja esperada melhora completa do equilíbrio corporal, a Reabilitação Vestibular é uma terapia eficaz na recuperação desses pacientes. Abstract in english Bilateral vestibular loss is a rare diagnosis among patients with dizziness and imbalance. Nevertheless, symptoms are often disabling and therapy is yet to be establish. AIM: To evaluate and describe the clinical outcome of patients with imbalance due to bilateral vestibular loss after caloric test, treated with An analog visual scale was used to evaluated clinical results. Vestibular Rehabilitation. STUDY DESIGN: Retrospective case report. METHOD: Pre and post treatment (more) outcomes were evaluated in 8 individuals suffering from post caloric bilateral vestibular paresis whose were submitted to vestibular rehabilitation. RESULTS: After Vestibular Rehabilitation, 7 (87,5%) of 8 patients had clinical improvement. CONCLUSION: Although is not expected entirely compensation for bilateral vestibular loss, the vestibular rehabilitation may be use as a therapeutic method for these patients.

Bittar, Roseli Saraiva Moreira; Bottino, Marco Aurélio; Pedalini, Maria Elisabete Bovino; Ramalho, Jeanne da Rosa Oiticica; Carneiro, Camila de Giacomo

2004-04-01

178

BETAHISTINE DIHYDROCHLORIDE IN CANINE PERIPHERAL VESTIBULAR SYNDROME DICLORIDRATO DE BETAISTINA NA SÍNDROME VESTIBULAR PERIFÉRICA CANINA  

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Full Text Available Vestibular disease is a common syndrome in small animals that  may resulst of central or peripheral disease. The pathophysiology of peripheral vestibular syndrome is unknown, however it can be related to an abnormal dynamic of endolymphatic fluid or neuritis of the vestibular portion of the VIII cranial nerve.  The recovery of neurological sings is slow and, in chronic cases, the neurological deficits can be irreversible. In veterinary medicine, thera are few medical options to treat this condition, however, in Medicine, betahistine dihydrochloride is used to treat peripheral vestibular disorders. These drug  was used in four dogs with vestibular syndrome. The results showed clinical improvement in 7 to 10 days of treatment and completed recovery in 20 to 30 days, followed by the cure. One year after the treatment, the dogs did not have recurrence of the syndrome. This report shows the use of betahistine dihydrochloride in dogs with peripheral vestibular syndrome, with rapid clinical recover, without laboratorial abnormalities or recurrence of the clinical signs .The results encourage the use of betahistine dihydrochloride in the treatment of  peripheral vestibular disorders in small animals.KEY WORDS: Betahistine, dog, vestibular syndrome. A síndrome vestibular periférica é uma condição clínica comum em cães. Várias doenças podem causar essa síndrome. Entretanto, sua patofisiologia ainda é pouco conhecida. As alterações clínicas geralmente são autolimitantes, a recuperação pode ser longa e, em casos crônicos, os déficits neurológicos podem ser irreversíveis. Em medicina veterinária, há poucas opções terapêuticas. Na Medicina, o dicloridrato de betaístina é amplamente utilizado. Essa medicação foi empregada em seis cães com síndrome vestibular periférica. Os resultados mostraram melhora clínica com sete a dez dias de tratamento e recuperação quase completa entre vinte e trinta dias. Este trabalho descreve a utilização da betaistina em cães com síndrome vestibular periférica, a rápida melhora clínica e ausência de efeitos adversos. Os resultados obtidos parecem justificar o uso de dicloridrato de betaistina na terapia de distúrbios vestibulares periféricos em animais de companhia.PALAVRAS-CHAVES: Betaistina, cão, síndrome vestibular.

Alexandre Martini de Brum; João Paulo da Exaltação Pascon; Tatiana Champion; Mirela Tinucci-Costa

2010-01-01

179

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

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

Ariane Solci Bonucci; Orozimbo Alves Costa Filho; Luciane Domingues Figueiredo Mariotto; Regina Célia Bortoleto Amantini; Kátia de Freitas Alvarenga

2008-01-01

180

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A ocorrência de alteração no equilíbrio no período pós-cirúrgico ao implante coclear varia de 31 a 75%. OBJETIVO: Analisar a função vestibular no período pré e pós-operatório da cirurgia de implante coclear. MATERIAL E MÉTODO: Avaliou-se a função vestibular, por meio da vectoeletronistagmografia, de 38 pacientes, no pré e pós-cirúrgico de implante coclear. RESULTADOS: A principal queixa de desequilíbrio apresentada pelos pacientes foi a tontura, seguid (more) a pela vertigem postural e pela vertigem não-postural. Dos 38 pacientes avaliados, 13% deixaram de apresentar desequilíbrio após a cirurgia de implante coclear e apenas 5% referiram piora. Houve uma melhora na sintomatologia vestibular em 13% dos pacientes, sendo que esta possibilidade pode estar relacionada ao fenômeno de compensação vestibular e pela estimulação elétrica. Entretanto, foi observada na prova calórica uma piora na funcionalidade do sistema vestibular, tanto na orelha implantada como na orelha não-implantada. Assim, não há tendência de maior comprometimento na orelha implantada. CONCLUSÃO: O estudo demonstrou que o implante coclear pode comprometer o sistema vestibular em ambas as orelhas. Entretanto, a sintomatologia vestibular ocorre em menor proporção, podendo haver melhora no desequilíbrio após a cirurgia do implante coclear. Abstract in english Balance alterations in the postoperative of cochlear implant surgeries varies from 31 to 75%. AIM: to analyze vestibular function in the pre and postoperative periods of cochlear implanted individuals. MATERIALS AND METHODS: the vestibular function was assessed, through electronystagmography, in 38 patients, in the pre and postoperative of cochlear implant procedures. RESULTS: The main complaint of unbalance reported by patients was dizziness, followed by postural vertigo (more) and non-postural vertigo. Results: 13% of the patients did not show any balance disorder following cochlear implant surgery and just 5% showed symptoms worsening. 13 % of the patients showed an improvement, and this could be related to the vestibular compensation phenomenon and to electric stimulation. However, it was observed, in the caloric responses, a worsening in the vestibular system function, for both implanted and non-implanted ears. Thus, there is no evidence of more damage to the implanted ear. CONCLUSION: the study showed that cochlear implant surgeries could injure the vestibular system in both ears. However, the vestibular symptoms take place in a smaller proportion, and can improve after cochlear implant surgery.

Bonucci, Ariane Solci; Costa Filho, Orozimbo Alves; Mariotto, Luciane Domingues Figueiredo; Amantini, Regina Célia Bortoleto; Alvarenga, Kátia de Freitas

2008-04-01

 
 
 
 
181

Comparação de diferentes protocolos de reabilitação vestibular em pacientes com disfunções vestibulares periféricas Comparison of different protocols for vestibular rehabilitation in patients with peripheral vestibular disorders  

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Full Text Available OBJETIVO: Comparar a eficácia terapêutica de dois protocolos de reabilitação vestibular em diferentes disfunções vestibulares. MÉTODOS: Participaram 20 pacientes com disfunções periféricas crônicas, de ambos os gêneros (prevalência do gênero feminino, com 60% da amostra), com média de idade de 55 anos e 9 meses. O Grupo 1 realizou exercícios baseados na estimulação do reflexo vestíbulocular vertical e horizontal, e o Grupo 2 realizou exercícios baseados em um protocolo de reabilitação vestibular personalizado. A análise de dados levou em consideração a queixa durante a anamnese e a evolução clínica do paciente a partir da execução dos exercícios. Além disso, foram obtidos os resultados do questionário Dizziness Handicap Inventory (DHI) e da escala analógica e visual de tontura (EVA), pré e pós reabilitação vestibular. RESULTADOS: Houve diferença nos valores da EVA e do DHI (escala física, funcional e no valor total), pré e pós-reabilitação vestibular, em ambos os grupos. Porém, na comparação dos dois grupos no momento pós-reabilitação, o Grupo 2 obteve melhores resultados que o Grupo 1, tanto na EVA quanto no DHI (escala funcional e no valor total). CONCLUSÃO: A reabilitação vestibular possibilitou melhora significativa do quadro otoneurológico clínico e na auto-percepção da tontura independentemente da terapêutica empregada. A reabilitação vestibular personalizada mostrou-se mais eficaz do que o protocolo de estimulação do reflexo vestibulocular na melhora da qualidade de vida de indivíduos com disfunções periféricas crônicasPURPOSE: To compare the therapeutic efficacy of two protocols for vestibular rehabilitation in several vestibular disordes. METHODS: Twenty patients with chronic peripheral disorders of both genders (prevalence of females, with 60% of the sample) and mean age of 55 years and 9 months participated in this study. Group 1 carried out exercices based on stimulation of vertical and horizontal vestibulocular reflex, and Group 2 carried out exercices based on a protocol of personalized vestibular rehabilitation. Data analysis considered the complaint manifested during anamnesis and the clinical evolution of the patient during the execution of the exercises. The results obtained from the application of the Dizziness Handicap Inventory questionnaire (DHI) and the dizziness visual analog scale (VAS), both before and after vestibular rehabilitation, were also considered in the analysis. RESULTS: Differences were found in the values obtained in VAS and DHI (physical and functional scales and total score), in both groups. However, the comparison of the groups after rehabilitation showed that Group 2 obtained better scores than Group 1, both in VAS and DHI (functional scale and total value). CONCLUSION: Vestibular rehabilitation allowed significant improvement in otoneurological clinical profile and in self-perception of dizziness, regardless the therapeutic method used. Personalized vestibular rehabilitation was more efficient than the vestibulocular reflex stimulation protocol in improving quality of life of individuals with chronic periferal disorders

Pâmela Garcia Morozetti; Cristina Freitas Ganança; Brasília Maria Chiari

2011-01-01

182

Comparação de diferentes protocolos de reabilitação vestibular em pacientes com disfunções vestibulares periféricas/ Comparison of different protocols for vestibular rehabilitation in patients with peripheral vestibular disorders  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese OBJETIVO: Comparar a eficácia terapêutica de dois protocolos de reabilitação vestibular em diferentes disfunções vestibulares. MÉTODOS: Participaram 20 pacientes com disfunções periféricas crônicas, de ambos os gêneros (prevalência do gênero feminino, com 60% da amostra), com média de idade de 55 anos e 9 meses. O Grupo 1 realizou exercícios baseados na estimulação do reflexo vestíbulocular vertical e horizontal, e o Grupo 2 realizou exercícios baseado (more) s em um protocolo de reabilitação vestibular personalizado. A análise de dados levou em consideração a queixa durante a anamnese e a evolução clínica do paciente a partir da execução dos exercícios. Além disso, foram obtidos os resultados do questionário Dizziness Handicap Inventory (DHI) e da escala analógica e visual de tontura (EVA), pré e pós reabilitação vestibular. RESULTADOS: Houve diferença nos valores da EVA e do DHI (escala física, funcional e no valor total), pré e pós-reabilitação vestibular, em ambos os grupos. Porém, na comparação dos dois grupos no momento pós-reabilitação, o Grupo 2 obteve melhores resultados que o Grupo 1, tanto na EVA quanto no DHI (escala funcional e no valor total). CONCLUSÃO: A reabilitação vestibular possibilitou melhora significativa do quadro otoneurológico clínico e na auto-percepção da tontura independentemente da terapêutica empregada. A reabilitação vestibular personalizada mostrou-se mais eficaz do que o protocolo de estimulação do reflexo vestibulocular na melhora da qualidade de vida de indivíduos com disfunções periféricas crônicas Abstract in english PURPOSE: To compare the therapeutic efficacy of two protocols for vestibular rehabilitation in several vestibular disordes. METHODS: Twenty patients with chronic peripheral disorders of both genders (prevalence of females, with 60% of the sample) and mean age of 55 years and 9 months participated in this study. Group 1 carried out exercices based on stimulation of vertical and horizontal vestibulocular reflex, and Group 2 carried out exercices based on a protocol of perso (more) nalized vestibular rehabilitation. Data analysis considered the complaint manifested during anamnesis and the clinical evolution of the patient during the execution of the exercises. The results obtained from the application of the Dizziness Handicap Inventory questionnaire (DHI) and the dizziness visual analog scale (VAS), both before and after vestibular rehabilitation, were also considered in the analysis. RESULTS: Differences were found in the values obtained in VAS and DHI (physical and functional scales and total score), in both groups. However, the comparison of the groups after rehabilitation showed that Group 2 obtained better scores than Group 1, both in VAS and DHI (functional scale and total value). CONCLUSION: Vestibular rehabilitation allowed significant improvement in otoneurological clinical profile and in self-perception of dizziness, regardless the therapeutic method used. Personalized vestibular rehabilitation was more efficient than the vestibulocular reflex stimulation protocol in improving quality of life of individuals with chronic periferal disorders

Morozetti, Pâmela Garcia; Ganança, Cristina Freitas; Chiari, Brasília Maria

2011-03-01

183

Periodic alternating nystagmus of peripheral vestibular origin.  

UK PubMed Central (United Kingdom)

Objective: Periodic alternating nystagmus (PAN) is most commonly found either in its congenital form or after cerebellar/pontomedullary lesions. However, we identified PAN in 10 patients with peripheral vestibular disorders and try to describe their characteristics to aid in the differential diagnosis between peripheral and central etiologies. Study design: Observation of a case series. Method: Peripheral vestibular lesions were confirmed by neurological examinations, vestibular function tests, and brain MRIs. Eye movements of the patients were recorded using electronystagmography or video nystagmography for a minimum of 10 minutes to confirm the nystagmus change in direction. Results: The final diagnoses of the patients included Meniere's disease (n = 3), acute labyrinthitis (n = 4), sudden sensorineural hearing loss with vertigo (n = 2), and vestibular schwannoma (n = 1). Direction-changing spontaneous horizontal nystagmus with quiescent intervals was observed in all patients under dark conditions. The nystagmus was suppressed by visual fixation, and the results of oculomotor tests were normal for saccadic and smooth pursuit eye movements and optokinetic nystagmus. All patients showed mild to complete canal paresis on a bithermal caloric test. PAN progressed into unidirectional nystagmus of the contra-lesion side in all patients within 48 hours. Conclusion: PAN can be observed in patients with peripheral vestibular disorders, but detecting PAN in this subpopulation is difficult because of its transitory nature. The absence of central symptoms and signs, the visual suppression of PAN, normal oculomotor tests, and transient persistence are important diagnostic clues for differentiating peripheral from central PAN. Laryngoscope, 2013.

Kim SH; Chung WK; Kim BG; Hwang CS; Kim MJ; Lee WS

2013-08-01

184

[Is the sense of verticality vestibular?].  

UK PubMed Central (United Kingdom)

The vestibular system constitutes an inertial sensor, which detects linear (otoliths) and angular (semicircular canals) accelerations of the head in the three dimensions. The otoliths are specialized in the detection of linear accelerations and can be used by the brain as a "plumb line" coding earth gravity acceleration (direction). This property of otolithic system suggested that the sense of verticality is supported by the vestibular system. The preeminence of vestibular involvement in the sense of verticality stated in the 1900s was progressively supplanted by the notion of internal models of verticality. The internal models of verticality involve rules and properties of integration of vestibular graviception, somaesthesic graviception, and vision. The construction of a mental representation of verticality was mainly modeled as a bottom-up organization integrating visual, somatosensory and vestibular information without any cognitive modulations. Recent studies reported that the construction of internal models of verticality is not an automatic multi-sensory integration process but corresponds to more complex mechanisms including top-down influences such as awareness of body orientation or spatial representations.

Barra J; Pérennou D

2013-06-01

185

[Cervical electrostimulation in some vestibular diseases].  

Science.gov (United States)

Vestibular disorders may be treated by means of drugs, surgical tools or rehabilitation. Cervical electrostimulation may be regarded as physical therapy and its activity is connected to neural pathways between cervical receptors and vestibular nuclei. In present study electrodes were placed lateral to cervical column on the opposite side of vestibular deficit as pointed by electronystagmography; stimulus duration was 18 msec and frequency 100 Hz. Every stimulation lasts for 30 minutes and were repeated twice a week for a total number of 10. The ability to adjust vestibulo-ocular reflex was evaluated by means of a Compensatory Index. The following materials were enrolled in the study: 20 normal subjects were observed before and after a cycle of stimulations: 24 patients suffering from acute labyrinthitis or neuritis, 48 cervical vertigo, 8 cervical traumatic injures and 3 patients operated for acoustical neuroma. All these groups were coupled with control groups composed of the same pathology and the same number of subjects. Statistical treatment of reports was evaluated by t-student test before therapy after one month and after 3 months. Results point out good effects of electrostimulation on vestibulo-ocular reflex compensation, especially in cervical vertigo and labyrinthitis or neuritis with respect to control groups. No important results were obtained in neuroma group and in normal subjects. Electrostimulation may act on vestibular nuclei by direct spino-vestibular pathway but also by repeated decompensations mainly mediated via the cerebellum or spino-reticular connections. PMID:7856453

Mosca, F

186

[Cervical electrostimulation in some vestibular diseases  

UK PubMed Central (United Kingdom)

Vestibular disorders may be treated by means of drugs, surgical tools or rehabilitation. Cervical electrostimulation may be regarded as physical therapy and its activity is connected to neural pathways between cervical receptors and vestibular nuclei. In present study electrodes were placed lateral to cervical column on the opposite side of vestibular deficit as pointed by electronystagmography; stimulus duration was 18 msec and frequency 100 Hz. Every stimulation lasts for 30 minutes and were repeated twice a week for a total number of 10. The ability to adjust vestibulo-ocular reflex was evaluated by means of a Compensatory Index. The following materials were enrolled in the study: 20 normal subjects were observed before and after a cycle of stimulations: 24 patients suffering from acute labyrinthitis or neuritis, 48 cervical vertigo, 8 cervical traumatic injures and 3 patients operated for acoustical neuroma. All these groups were coupled with control groups composed of the same pathology and the same number of subjects. Statistical treatment of reports was evaluated by t-student test before therapy after one month and after 3 months. Results point out good effects of electrostimulation on vestibulo-ocular reflex compensation, especially in cervical vertigo and labyrinthitis or neuritis with respect to control groups. No important results were obtained in neuroma group and in normal subjects. Electrostimulation may act on vestibular nuclei by direct spino-vestibular pathway but also by repeated decompensations mainly mediated via the cerebellum or spino-reticular connections.

Mosca F

1994-09-01

187

[Is the sense of verticality vestibular?].  

Science.gov (United States)

The vestibular system constitutes an inertial sensor, which detects linear (otoliths) and angular (semicircular canals) accelerations of the head in the three dimensions. The otoliths are specialized in the detection of linear accelerations and can be used by the brain as a "plumb line" coding earth gravity acceleration (direction). This property of otolithic system suggested that the sense of verticality is supported by the vestibular system. The preeminence of vestibular involvement in the sense of verticality stated in the 1900s was progressively supplanted by the notion of internal models of verticality. The internal models of verticality involve rules and properties of integration of vestibular graviception, somaesthesic graviception, and vision. The construction of a mental representation of verticality was mainly modeled as a bottom-up organization integrating visual, somatosensory and vestibular information without any cognitive modulations. Recent studies reported that the construction of internal models of verticality is not an automatic multi-sensory integration process but corresponds to more complex mechanisms including top-down influences such as awareness of body orientation or spatial representations. PMID:23856176

Barra, J; Pérennou, D

2013-03-14

188

Role of cervical vestibular evoked myogenic potential response in identifying vestibular dysfunction.  

UK PubMed Central (United Kingdom)

Objectives: To analyse cervical vestibular evoked myogenic potential response parameters in normal volunteers and vertiginous patients. Subjects and methods: A prospective study of 50 normal subjects and 50 patients with vertigo was conducted at Chiang Mai University Hospital, Thailand. Cervical vestibular evoked myogenic potential responses were measured using air-conducted, 500-Hz, tone-burst stimuli with subjects in a sitting position with their head turned toward the contralateral shoulder. Results: The mean ± standard deviation age and male:female ratio in the normal (44.0 ± 9.3 years; 12:38) and vertigo groups (44.7 ± 9.8 years; 17:33) were not significantly different. The prevalence of absent responses in the normal (14 per cent) and vertigo ears (46 per cent) differed significantly (p < 0.0001). Other cervical vestibular evoked myogenic potential parameters (i.e. response threshold, P1 and N1 latency, P1-N1 interlatency and interamplitude, inter-ear difference in P1 threshold, and asymmetry ratio) showed no inter-group differences. Conclusion: The absence of a cervical vestibular evoked myogenic potential response is useful in the identification of vestibular dysfunction. However, patients should undergo a comprehensive battery of other vestibular tests to supplement their cervical vestibular evoked myogenic potential response findings.

Isaradisaikul S; Navacharoen N; Hanprasertpong C; Kangsanarak J

2013-08-01

189

Quality of life of individuals submitted to vestibular rehabilitation/ Qualidade de vida de indivíduos submetidos à reabilitação vestibular  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Desordens do equilíbrio comprometem atividades sociais, familiares e profissionais. A reabilitação vestibular pode reduzir o impacto dessas desordens na qualidade de vida dos indivíduos vertiginosos. OBJETIVO: Verificar a influência da reabilitação vestibular sobre a qualidade de vida dos indivíduos, correlacionando-a com gênero, idade, resultado da vectoeletronistagmografia computadorizada e presença de vertigem. Forma de Estudo: Retrospectivo. MATERIAL E MÉTO (more) DO: Vinte e dois indivíduos foram submetidos à reabilitação vestibular personalizada e ao Dizziness Handicap Inventory - DHI brasileiro - pré e pós-reabilitação vestibular. Os resultados desse questionário foram correlacionados com as variáveis gênero, idade, avaliação vestibular e presença de tontura do tipo vertigem. RESULTADOS: Todos os escores do DHI diminuíram significantemente após reabilitação vestibular. Não houve diferença entre gêneros; adultos e idosos; síndromes vestibulares periféricas Irritativas, Deficitárias e exames Normais; e presença ou não de vertigem. CONCLUSÃO: Todos os indivíduos obtiveram melhora na qualidade de vida após a reabilitação vestibular personalizada. Abstract in english Balance disorders affect social, family and professional activities. Vestibular rehabilitation can reduce the impact of these disorders on the quality of life of individuals with vertigo. AIM: to study the influence of vestibular rehabilitation on the quality of life of individuals, correlating it with gender, age, results from computerized vectoelectronystagmography and vertigo. Study type: Retrospective. MATERIALS AND METHODS:Twenty-two individuals were submitted to cus (more) tomized vestibular rehabilitation and the Brazilian Dizziness Handicap Inventory - DHI before and after vestibular rehabilitation. Results from this questionnaire were correlated with gender, age, vestibular assessment and the presence of vertigo. RESULTS: all the DHI scores reduced significantly after vestibular rehabilitation. There were no differences among genders; adults and elderly patients; irritative peripheral vestibular syndromes; deficiency syndromes and normal exams; the presence or absence of vertigo. CONCLUSION: all the individuals had improvements in their quality of life after customized vestibular rehabilitation.

Patatas, Olívia Helena Gomes; Ganança, Cristina Freitas; Ganança, Fernando Freitas

2009-06-01

190

Quality of life of individuals submitted to vestibular rehabilitation Qualidade de vida de indivíduos submetidos à reabilitação vestibular  

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Full Text Available Balance disorders affect social, family and professional activities. Vestibular rehabilitation can reduce the impact of these disorders on the quality of life of individuals with vertigo. AIM: to study the influence of vestibular rehabilitation on the quality of life of individuals, correlating it with gender, age, results from computerized vectoelectronystagmography and vertigo. Study type: Retrospective. MATERIALS AND METHODS:Twenty-two individuals were submitted to customized vestibular rehabilitation and the Brazilian Dizziness Handicap Inventory - DHI before and after vestibular rehabilitation. Results from this questionnaire were correlated with gender, age, vestibular assessment and the presence of vertigo. RESULTS: all the DHI scores reduced significantly after vestibular rehabilitation. There were no differences among genders; adults and elderly patients; irritative peripheral vestibular syndromes; deficiency syndromes and normal exams; the presence or absence of vertigo. CONCLUSION: all the individuals had improvements in their quality of life after customized vestibular rehabilitation.Desordens do equilíbrio comprometem atividades sociais, familiares e profissionais. A reabilitação vestibular pode reduzir o impacto dessas desordens na qualidade de vida dos indivíduos vertiginosos. OBJETIVO: Verificar a influência da reabilitação vestibular sobre a qualidade de vida dos indivíduos, correlacionando-a com gênero, idade, resultado da vectoeletronistagmografia computadorizada e presença de vertigem. Forma de Estudo: Retrospectivo. MATERIAL E MÉTODO: Vinte e dois indivíduos foram submetidos à reabilitação vestibular personalizada e ao Dizziness Handicap Inventory - DHI brasileiro - pré e pós-reabilitação vestibular. Os resultados desse questionário foram correlacionados com as variáveis gênero, idade, avaliação vestibular e presença de tontura do tipo vertigem. RESULTADOS: Todos os escores do DHI diminuíram significantemente após reabilitação vestibular. Não houve diferença entre gêneros; adultos e idosos; síndromes vestibulares periféricas Irritativas, Deficitárias e exames Normais; e presença ou não de vertigem. CONCLUSÃO: Todos os indivíduos obtiveram melhora na qualidade de vida após a reabilitação vestibular personalizada.

Olívia Helena Gomes Patatas; Cristina Freitas Ganança; Fernando Freitas Ganança

2009-01-01

191

Diagnóstico e tratamento das principais síndromes vestibulares/ Diagnosis and treatment of the most frequent vestibular syndromes  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Os objetivos deste estudo foram identificar as síndromes vestibulares mais comuns nos ambulatórios de vertigem, suas características clínicas e semiológicas, e observar a resposta ao tratamento específico. Foram estudados retrospectivamente 515 pacientes atendidos em ambulatórios de duas instituições e avaliados aspectos da anamnese, exame físico e a resposta ao tratamento. As síndromes mais freqüentes foram: vertigem de posicionamento paroxística benigna (VP (more) PB) (28,5%), vertigem postural fóbica (11,5%), vertigem central (10,1%), neurite vestibular (9,7%), doença de Menière (8,5%), enxaqueca (6,4%). Houve boa resposta ao tratamento nos pacientes com enxaqueca (78,8%), VPPB (64%), neurite vestibular (62%), doença de Menière (54,5%) e paroxismia vestibular (54,5%), enquanto pacientes com nistagmo para baixo e vestibulopatia bilateral não tiveram resposta satisfatória (52,6% e 42,8% respectivamente). As síndromes vestibulares foram diagnosticadas através da anamnese e exame físico com testes clínicos específicos para avaliação da função vestibular. A identificação destas síndromes permitiu o tratamento adequado levando a uma boa evolução. Abstract in english The aims of this study were to identify the most common vestibular syndromes in a dizziness unit, and to observe their clinical aspects and response to treatment. Five hundred and fifteen patients were studied retrospectively in two institutions. Aspects of anamnesis, physical examination and the response to treatment were evaluated. The most frequent syndromes were: benign paroxysmal positioning vertigo (VPPB) (28.5%), phobic postural vertigo (11.5%), central vertigo (10 (more) .1%), vestibular neuritis (9.7%), Menière disease (8.5%), and migraine (6.4%). A good response to treatment was observed in most patients with migraine (78.8%), VPPB (64%), vestibular neuritis (62%), Menière disease (54.5%) and vestibular paroxismia (54.5%). On the other hand, patients with downbeat nystagmus and bilateral vestibulopathy had poor response (52.6% and 42.8%, respectively). The diagnosis of these most frequent vestibular syndromes were established through anamnesis and physical examination (with specific clinical tests for evaluation of the vestibular function). The correct diagnosis and adequate treatment are important since these syndromes may have a good prognosis.

Kanashiro, Aline Mizuta Kozoroski; Pereira, Cristiana Borges; Melo, Antonio Carlos de Paiva; Scaff, Milberto

2005-03-01

192

Diagnóstico e tratamento das principais síndromes vestibulares Diagnosis and treatment of the most frequent vestibular syndromes  

Directory of Open Access Journals (Sweden)

Full Text Available Os objetivos deste estudo foram identificar as síndromes vestibulares mais comuns nos ambulatórios de vertigem, suas características clínicas e semiológicas, e observar a resposta ao tratamento específico. Foram estudados retrospectivamente 515 pacientes atendidos em ambulatórios de duas instituições e avaliados aspectos da anamnese, exame físico e a resposta ao tratamento. As síndromes mais freqüentes foram: vertigem de posicionamento paroxística benigna (VPPB) (28,5%), vertigem postural fóbica (11,5%), vertigem central (10,1%), neurite vestibular (9,7%), doença de Menière (8,5%), enxaqueca (6,4%). Houve boa resposta ao tratamento nos pacientes com enxaqueca (78,8%), VPPB (64%), neurite vestibular (62%), doença de Menière (54,5%) e paroxismia vestibular (54,5%), enquanto pacientes com nistagmo para baixo e vestibulopatia bilateral não tiveram resposta satisfatória (52,6% e 42,8% respectivamente). As síndromes vestibulares foram diagnosticadas através da anamnese e exame físico com testes clínicos específicos para avaliação da função vestibular. A identificação destas síndromes permitiu o tratamento adequado levando a uma boa evolução.The aims of this study were to identify the most common vestibular syndromes in a dizziness unit, and to observe their clinical aspects and response to treatment. Five hundred and fifteen patients were studied retrospectively in two institutions. Aspects of anamnesis, physical examination and the response to treatment were evaluated. The most frequent syndromes were: benign paroxysmal positioning vertigo (VPPB) (28.5%), phobic postural vertigo (11.5%), central vertigo (10.1%), vestibular neuritis (9.7%), Menière disease (8.5%), and migraine (6.4%). A good response to treatment was observed in most patients with migraine (78.8%), VPPB (64%), vestibular neuritis (62%), Menière disease (54.5%) and vestibular paroxismia (54.5%). On the other hand, patients with downbeat nystagmus and bilateral vestibulopathy had poor response (52.6% and 42.8%, respectively). The diagnosis of these most frequent vestibular syndromes were established through anamnesis and physical examination (with specific clinical tests for evaluation of the vestibular function). The correct diagnosis and adequate treatment are important since these syndromes may have a good prognosis.

Aline Mizuta Kozoroski Kanashiro; Cristiana Borges Pereira; Antonio Carlos de Paiva Melo; Milberto Scaff

2005-01-01

193

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

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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 (55.5%), empty head sensations, agitation during sleep and depression (51.8%) in each one. The vestibular exam showed alterations in 20 patients (74.0%) in the caloric test. There was a prevalence of alterations in the peripheral vestibular system. There was a prevalence of deficient peripheral vestibular syndrome. CONCLUSION: the importance of studying the relationship between the vestibular system and temporomandibular joint dysfunction is emphasized, since a high number of alterations in the labyrinthic exam have been noted in this research.

Bianca Simone Zeigelboim; Ari Leon Jurkiewicz; Jackeline Martins-Bassetto; Karlin Fabianne Klagenberg

2007-01-01

194

The vestibular nuclei and vestibuloreticular connections in the mallard (Anas platyrhynchos L.). An anterograde and retrograde tracing study.  

UK PubMed Central (United Kingdom)

The vestibular apparatus provides information about the position and movements of the head. Craniocervical muscles position the head with respect to the upper part of the neck. Motoneurons innervating these muscles are located in the supraspinal nucleus and ventral horn of the rostral cervical cord. Premotor neurons of craniocervical muscles have been found in the medial two-thirds of the medullary reticular formation: the ventromedial part of the parvocellular reticular formation and the gigantocellular reticular formation. In the present study, projections from vestibular nuclei upon craniocervical premotor neurons were investigated using anterograde and retrograde tracers. Vestibulospinal fibers run bilaterally in the medial vestibulospinal tract and ipsilaterally in the lateral vestibulospinal tract. Vestibuloreticular projections are mainly ipsilateral, and originate from the n. vestibularis lateralis pars ventralis and pars dorsalis, and from the n. vestibularis descendens. Terminal labeling is found in the border zone between the parvocellular and gigantocellular reticular formation. These projections show that in addition to direct bilateral vestibulo-craniocervical projections an indirect vestibular pathway to craniocervical motor nuclei exists. The direct pathway probably is the neural substrate for the vestibulocollic reflex, whereas the vestibular projection upon the reticular formation might influence head orientation during various kinds of activities, such as pecking, preening and so on.

Tellegen AJ; Arends JJ; Dubbeldam JL

2001-01-01

195

The vestibular nuclei and vestibuloreticular connections in the mallard (Anas platyrhynchos L.). An anterograde and retrograde tracing study.  

Science.gov (United States)

The vestibular apparatus provides information about the position and movements of the head. Craniocervical muscles position the head with respect to the upper part of the neck. Motoneurons innervating these muscles are located in the supraspinal nucleus and ventral horn of the rostral cervical cord. Premotor neurons of craniocervical muscles have been found in the medial two-thirds of the medullary reticular formation: the ventromedial part of the parvocellular reticular formation and the gigantocellular reticular formation. In the present study, projections from vestibular nuclei upon craniocervical premotor neurons were investigated using anterograde and retrograde tracers. Vestibulospinal fibers run bilaterally in the medial vestibulospinal tract and ipsilaterally in the lateral vestibulospinal tract. Vestibuloreticular projections are mainly ipsilateral, and originate from the n. vestibularis lateralis pars ventralis and pars dorsalis, and from the n. vestibularis descendens. Terminal labeling is found in the border zone between the parvocellular and gigantocellular reticular formation. These projections show that in addition to direct bilateral vestibulo-craniocervical projections an indirect vestibular pathway to craniocervical motor nuclei exists. The direct pathway probably is the neural substrate for the vestibulocollic reflex, whereas the vestibular projection upon the reticular formation might influence head orientation during various kinds of activities, such as pecking, preening and so on. PMID:11964497

Tellegen, A J; Arends, J J; Dubbeldam, J L

2001-01-01

196

Assessment of gentamicin-induced vestibulotoxicity by click and galvanic vestibular-evoked myogenic potentials: a guinea pig investigation.  

UK PubMed Central (United Kingdom)

OBJECTIVE: The aim of this investigation carried out with guinea pigs was to study the possible effects of a gentamicin treatment on the saccular macula and on its afferent vestibular ganglion neurons. METHODS: The gentamicin-induced impairment was analyzed using vestibular-evoked myogenic potentials (VEMPs) elicited by both click and galvanic vestibular stimulations (GVS). Fifty microl of saline or gentamicin solution (40 mg/ml) was dropped over the round window membrane of the right (control) and left (lesion) cochleae, respectively. Four weeks after surgery, the VEMPs elicited with clicks and GVS were evaluated for each animal. Then, the animals were sacrificed in order to perform morphological and anti-Nav1.8 immunocytochemical analyses. RESULTS: Click- and GVS-VEMPs were obtained in all of the controls, whereas no potentials were obtained from gentamicin-treated animals. Lesions of sensory cells were observed in the saccular macula. In the injured vestibular ganglion, the percentage of voltage-gated sodium channel Nav1.8-like immunoreactive (Nav1.8-LI) neurons was significantly lower (38.9+/-0.7) than that (53.6+/-3.2) calculated in controls. CONCLUSIONS: Gentamicin-induced impairments of the saccular macula and afferents of guinea pigs can be evaluated by recording both click- and GVS-VEMPs. Both tests provide information on the sacculo-collic reflex pathway and could help a clinical diagnosis of gentamicin intoxication by conventional eardrops in the patient with a perforated eardrum.

Cheng PW; Lue JH; Lin CT; Day AS; Young YH

2010-01-01

197

Vestibular folds configuration in vocal nodule.  

UK PubMed Central (United Kingdom)

UNLABELLED: Vocal nodules are among the most common laryngopathies that cause vocal functional disorders. The voice production mechanism is complex and demand interaction of different systems of the human body. The physiological role of the vocal folds as the glottic sound source is evident, however, there is no consensus regarding the vestibular folds' participation/influence in phonation. AIM: To verify if there is difference in the bidimensional configuration of the vestibular folds between two distinct groups of women, one with the diagnosis of vocal nodules and the other without vocal complaints and vocal fold lesions. STUDY DESIGN: Clinical with transversal cohort. MATERIAL AND METHOD: Ninety-six laryngeal images were evaluated, 48 from individuals without vocal complaints and 48 from patients with the diagnosis of vocal nodules. Angles were obtained and bilaterally measured in single frames of the vestibular folds during sustained phonation and those structures were morphologically classified as concave, linear or convex. RESULTS: Among the 96 vestibular folds evaluated in each group, there was predominance of the concave form, followed by the linear and the convex ones. In the control group, there was a single convex vestibular fold, 27 were linear and 68 were concave folds. In the group of vocal nodules, 8 were convex, 15 were linear and 73 were concave folds. However, the differences among groups were not statistically significant as well as those among the angles, whose average measures were proven quite similar. CONCLUSION: In the female gender, the vestibular folds presented similar behavior regarding the morphology in both patients with vocal nodules and women without vocal complaints.

Tuma J; Brasil OO; Pontes PA; Yasaki RK

2005-09-01

198

Vestibular hemispatial neglect: patterns and possible mechanism.  

UK PubMed Central (United Kingdom)

Recent reports have suggested that hemispatial neglect may be a vestibular disorder at the cortical level, based on the similarities of symptoms and neural correlates between the two phenomena. If this is the case, peripheral vestibulopathy may lead to hemispatial neglect. However, the etiology of hemispatial neglect in patients with unilateral peripheral vestibulopathy remains unclear. The aims of the present study were to investigate the following: (1) if unilateral peripheral vestibulopathy might cause hemispatial neglect, and if so, (2) whether hemispatial neglect in unilateral peripheral vestibulopathy might be induced by horizontal bias for eye position and body orientation or whether it is secondary to vestibular cortical dysfunction following unilateral peripheral vestibulopathy. Twenty-five consecutive patients with acute vestibular neuritis were recruited at the Dizziness Clinic of Pusan National University Hospital. All participants underwent neglect testing and measurements of horizontal bias for eye position and head and body orientation. Hemispatial neglect occurred in 32 % of patients with unilateral peripheral vestibulopathy. The frequency of contralesional neglect was equal to that of ipsilesional neglect. All patients with hemispatial neglect showed abnormal performance in bisection tasks. The incidence and severity of the horizontal bias of eye position and head and body orientation did not differ between patients with or without hemispatial neglect. Our study demonstrates that hemispatial neglect can develop after acute unilateral peripheral vestibulopathy. Hemispatial neglect after acute unilateral peripheral vestibulopathy may be attributed to damaged vestibular subnuclei, which receive afferents from both peripheral vestibular end organs and the vestibulocerebellum and project to the ipsilateral or contralateral thalamus and vestibular cortex.

Choi KD; Jung DS; Jo MK; Kim MJ; Kim JS; Na DL; Kim EJ

2013-06-01

199

Temporal change in NMDA receptor signaling and GABAA receptor expression in rat caudal vestibular nucleus during motion sickness habituation.  

UK PubMed Central (United Kingdom)

Repeated exposure to a provocative motion stimulus leads to motion sickness habituation indicative of the existence of central processes to counteract the disturbing properties of the imposed motion. In the present study, we attempt to investigate whether NMDA and GABA(A) receptors in rat caudal vestibular nucleus neurons are involved in motion sickness habituation induced by repeated Ferris-wheel like rotation in daily session (2h/d). We showed that defecation response increased and spontaneous locomotion decreased within 4 sessions (sickness phase). They recovered back to the control level after 7 sessions (habituation phase). Western blot analysis found that NMDA receptor signal molecules: calmodulin protein kinase II and cAMP response element-binding protein (CREB) were both activated during sickness phase, while a prolonged CREB activation was also observed during habituation phase. Real-time quantitative PCR revealed an increase in c-fos and a decrease in Arc mRNA level during sickness phase. We also found an increase in GABA(A) receptor ?1 subunit (GABA(A) ?1) protein level in this stage. These results suggested that altered NMDA receptor signaling and GABA(A) receptor expression level in caudal vestibular nucleus were associated with motion sickness habituation. Furthermore, immunofluorescence and confocal laser scanning microscopy showed that the number of GABA(A) ?1 immunolabeled neurons in caudal vestibular nucleus increased while the number of GABA(A) ?1/Arc double labeled neurons and the average amount of Arc particle in soma of these neurons decreased during sickness phase. It suggested that GABA(A) receptor level might be negatively regulated by Arc protein in caudal vestibular nucleus neurons.

Wang JQ; Li HX; Chen XM; Mo FF; Qi RR; Guo JS; Cai YL

2012-06-01

200

VESTIBULAR NASAL STENOSIS. A clinical case  

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Full Text Available Iatrogenic vestibular stenosis is a blockage of the nasal vestibule caused by adisruption of the vestibular lining with secondary proliferation of fibrous tissue scar and granulation. It is more common as a result of foreign body reaction or nasal trauma. The lesions usually include the lobby and the anterior inferior turbinate. We report the case of a girl of eleven, with a complete and recurrent stenosis of the right nasal vestibule, and whose history was spent in the incubator at birth and feeding tube during this period with repeated aspirations traumatic nostril.

A. Fernández Rodríguez; D. Moráis Pérez; J. Santos Pérez; G. Blanco Mateos; T. Millás Gómez; G. Landínez Cepeda

2010-01-01

 
 
 
 
201

Vestibular schwannoma: anatomical, medical and surgical perspective  

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Full Text Available The term "acoustic" is a misnomer, as the tumor rarely arises from the acoustic (or cochlear) division of the vestibulocochlear nerve. The correct medical term is vestibular schwannoma, because it involves the vestibular portion of the 8th cranial nerve. They are benign, rather rare tumors. They expand in size and grow larger; they can push against the brain. While the tumor does not actually invade the brain, the pressure of the tumor can displace brain tissue. [Int J Res Med Sci 2013; 1(3.000): 178-182

Ashfaq Ul Hassan; Ghulam Hassan; Zahida Rasool

2013-01-01

202

Ocular vestibular evoked myogenic potentials in patients with acoustic neuroma.  

UK PubMed Central (United Kingdom)

To assess the usefulness of vestibular testing in patients with acoustic neuroma, considering two main aspects: to compare diagnostic sensitivity of the current vestibular tests, especially considering ocular vestibular evoked myogenic potentials (OVEMPs) and to identify pre-operative localization of the tumor (inferior vestibular nerve vs. superior vestibular nerve) only with the help of vestibular electrophysiological data. Twenty-six patients with unilateral acoustic neuroma (mainly intracanalicular type) were studied with a full audio-vestibular test battery (pure tone and speech audiometry, caloric bithermal test, vibration-induced nystagmus test (VIN), cervical and OVEMPs). 18 patients (69 %) showed abnormal caloric responses. 12 patients (46.2 %) showed a pattern of VIN test suggestive of vestibular asymmetry. 16 patients (61.5 %) showed abnormal OVEMPs (12 only to AC, 4 both to AC and BC). 10 patients (38.5 %) showed abnormal cervical vestibular evoked myogenic potentials (5 both to AC and BC, 5 only to AC). In one case, results of vestibular evoked potentials and caloric test were confirmed by intra-operative and post-operative findings. Results of electrophysiological tests in AN patients could be helpful for planning the proper surgical approach, considering that sensitivity of every exam is quite low in intracanalicular lesion; clinical data allow a better interpretation of vestibular evoked myogenic potentials.

Piras G; Brandolini C; Castellucci A; Modugno GC

2013-02-01

203

Viruses and vestibular neuritis: review of human and animal studies.  

UK PubMed Central (United Kingdom)

There is increasing evidence in man and animals that several human viruses can damage the vestibular labyrinth. Clinical and serologic studies of patients with vestibular neuritis suggest that the viruses may play a role in the pathogenesis of this disease. Temporal bone studies of patients dying after vestibular neuritis have found maximal damage in the distal branches of the vestibular nerve. These changes are felt to be consistent with a viral etiology. No satisfactory animal viral model of vestibular neuritis currently exists. However, animal studies have demonstrated that several human viruses including rubeola, herpes simplex, reovirus, mouse and guinea pig cytomegalovirus, and neurotropic strains of influenza A and mumps virus, can infect the vestibular nerve and the vestibular membranous labyrinth.

Davis LE

1993-01-01

204

Viruses and vestibular neuritis: review of human and animal studies.  

Science.gov (United States)

There is increasing evidence in man and animals that several human viruses can damage the vestibular labyrinth. Clinical and serologic studies of patients with vestibular neuritis suggest that the viruses may play a role in the pathogenesis of this disease. Temporal bone studies of patients dying after vestibular neuritis have found maximal damage in the distal branches of the vestibular nerve. These changes are felt to be consistent with a viral etiology. No satisfactory animal viral model of vestibular neuritis currently exists. However, animal studies have demonstrated that several human viruses including rubeola, herpes simplex, reovirus, mouse and guinea pig cytomegalovirus, and neurotropic strains of influenza A and mumps virus, can infect the vestibular nerve and the vestibular membranous labyrinth. PMID:8470506

Davis, L E

1993-01-01

205

Localization of aquaporins in the mouse vestibular end organs.  

UK PubMed Central (United Kingdom)

Abstract Conclusion: We found that aquaporins (AQPs) in the fluid transporting cells, such as vestibular dark cells and endolymphatic sac epithelial cells, seem to be of importance in fluid transport in the inner ear, while those in the sensory and ganglion cells may play a functional role in sensory cell transduction. Objective: Expression of AQPs (0-12) was analyzed in normal mouse vestibular end organs. Methods: CBA/J mice were used in this study. Localization of AQPs 0-12 in the vestibular end organs and endolymphatic sac was investigated by immunohistochemistry. Results: The AQPs were found abundantly distributed in many structures in the vestibular end organs, i.e. vestibular sensory and supporting cells, vestibular dark cells, vestibular ganglion cells, and the endolymphatic sac.

Takumida M; Takumida H; Kakigi A; Egami N; Nishioka R; Anniko M

2013-08-01

206

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

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

Monstad Per; Økstad Siri; Mygland Åse

2006-01-01

207

Opposite long-term synaptic effects of 17?-estradiol and 5?-dihydrotestosterone and localization of their receptors in the medial vestibular nucleus of rats.  

Science.gov (United States)

In brainstem slices of male rats, we examined in single neurons of the medial vestibular nucleus (MVN) the effect of exogenous administration of estrogenic (17?-estradiol, E2) and androgenic (5?-dihydrotestosterone, DHT) steroids on the synaptic response to vestibular afferent stimulation. By whole cell patch clamp recordings we showed that E2 induced synaptic long-term potentiation (LTP) that was cancelled by the subsequent administration of DHT. Conversely, DHT induced synaptic long-term depression (LTD) that was partially reversed by E2. The electrophysiological findings were supported by immunohistochemical analysis showing the presence of estrogen (ER: ? and ?) and androgen receptors (AR) in the MVN neurons. We found that a large number of neurons were immunoreactive for ER?, ER?, and AR and most of them co-localized ER? and AR. We also showed the presence of P450-aromatase (ARO) in the MVN neurons, clearly proving that E2 can be locally synthesized in the MVN. On the whole, these results demonstrate a role of estrogenic and androgenic signals in modulating vestibular synaptic plasticity and suggest that the enhancement or depression of vestibular synaptic response may depend on the local conversion of T into E2 or DHT. PMID:23701910

Grassi, Silvarosa; Scarduzio, Mariangela; Panichi, Roberto; Dall'aglio, Cecilia; Boiti, Cristiano; Pettorossi, Vito E

2013-05-20

208

Opposite long-term synaptic effects of 17?-estradiol and 5?-dihydrotestosterone and localization of their receptors in the medial vestibular nucleus of rats.  

UK PubMed Central (United Kingdom)

In brainstem slices of male rats, we examined in single neurons of the medial vestibular nucleus (MVN) the effect of exogenous administration of estrogenic (17?-estradiol, E2) and androgenic (5?-dihydrotestosterone, DHT) steroids on the synaptic response to vestibular afferent stimulation. By whole cell patch clamp recordings we showed that E2 induced synaptic long-term potentiation (LTP) that was cancelled by the subsequent administration of DHT. Conversely, DHT induced synaptic long-term depression (LTD) that was partially reversed by E2. The electrophysiological findings were supported by immunohistochemical analysis showing the presence of estrogen (ER: ? and ?) and androgen receptors (AR) in the MVN neurons. We found that a large number of neurons were immunoreactive for ER?, ER?, and AR and most of them co-localized ER? and AR. We also showed the presence of P450-aromatase (ARO) in the MVN neurons, clearly proving that E2 can be locally synthesized in the MVN. On the whole, these results demonstrate a role of estrogenic and androgenic signals in modulating vestibular synaptic plasticity and suggest that the enhancement or depression of vestibular synaptic response may depend on the local conversion of T into E2 or DHT.

Grassi S; Scarduzio M; Panichi R; Dall'aglio C; Boiti C; Pettorossi VE

2013-08-01

209

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

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

Masoud Motasaddi Zarandy; Mohammad Taghi Khorsandi; Nima Rezazadeh; Nasrin Yazdani; Farhad Mokhtarinejad; Arash Bayat; Masoomeh Ruzbehani

2011-01-01

210

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

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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.

Renato Cal; Fayez Bahmad Jr

2009-01-01

211

Paciente com cefaleia e síndrome vestibular periférica: relato de caso Patient with headache and peripheral vestibular dysfunction: case report  

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Full Text Available TEMA: a Reabilitação Vestibular constitui-se numa opção de tratamento para pacientes portadores de síndrome vestibular periférica e cefaleia. PROCEDIMENTOS: o paciente, do sexo feminino com 26 anos de idade apresentava síndrome vestibular periférica acompanhada de crises de cefaleia. Foi realizada avaliação e terapia fonoaudiológica com exercícios de habituação vestibular além de fisioterapia e dieta recomendada pelo nutricionista. RESULTADOS: no período de 3 meses com reabilitação vestibular realizada semanalmente observou-se melhora no quadro vertiginoso e da cefaleia da paciente. CONCLUSÕES: evidenciou-se boa eficácia clínica para o tratamento desta paciente através da reabilitação vestibular com exercícios de habituação vestibular. Salienta-se a eficácia da reabilitação para a melhora na qualidade de vida da paciente e minimização das crises de cefaleia.BACKGROUND: vestibular rehabilitation is an option for treating peripheral vestibular syndrome and headache patients. PROCEDURES: the patient is a 29-year old woman and has Peripheral Vestibular Syndrome along with headache attacks. Evaluation and Phonoaudiological therapy with exercises of habituation tests with physical and nutritional therapy were carried out. RESULTS: in 3 month period with weekly vestibular rehabilitation therapy, we observed an improvement in the condition of the patient's vertigo and migraine. CONCLUSIONS: it was evident that the patient's treatment through the rehabilitation test with habituation test exercises had good efficiency. Please note the effectiveness of the rehabilitation for the improvement in the patient's life quality and minimization of headache attacks.

Tatiane Maria Rossi; Naonne Santos Camargo Luciano; Polliay Freire Oricoli; Luciana Lozza de Moraes Marchiori; Juliana Jandre Melo

2009-01-01

212

Paciente com cefaleia e síndrome vestibular periférica: relato de caso/ Patient with headache and peripheral vestibular dysfunction: case report  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese TEMA: a Reabilitação Vestibular constitui-se numa opção de tratamento para pacientes portadores de síndrome vestibular periférica e cefaleia. PROCEDIMENTOS: o paciente, do sexo feminino com 26 anos de idade apresentava síndrome vestibular periférica acompanhada de crises de cefaleia. Foi realizada avaliação e terapia fonoaudiológica com exercícios de habituação vestibular além de fisioterapia e dieta recomendada pelo nutricionista. RESULTADOS: no período d (more) e 3 meses com reabilitação vestibular realizada semanalmente observou-se melhora no quadro vertiginoso e da cefaleia da paciente. CONCLUSÕES: evidenciou-se boa eficácia clínica para o tratamento desta paciente através da reabilitação vestibular com exercícios de habituação vestibular. Salienta-se a eficácia da reabilitação para a melhora na qualidade de vida da paciente e minimização das crises de cefaleia. Abstract in english BACKGROUND: vestibular rehabilitation is an option for treating peripheral vestibular syndrome and headache patients. PROCEDURES: the patient is a 29-year old woman and has Peripheral Vestibular Syndrome along with headache attacks. Evaluation and Phonoaudiological therapy with exercises of habituation tests with physical and nutritional therapy were carried out. RESULTS: in 3 month period with weekly vestibular rehabilitation therapy, we observed an improvement in the co (more) ndition of the patient's vertigo and migraine. CONCLUSIONS: it was evident that the patient's treatment through the rehabilitation test with habituation test exercises had good efficiency. Please note the effectiveness of the rehabilitation for the improvement in the patient's life quality and minimization of headache attacks.

Rossi, Tatiane Maria; Luciano, Naonne Santos Camargo; Oricoli, Polliay Freire; Marchiori, Luciana Lozza de Moraes; Melo, Juliana Jandre

2009-01-01

213

Perspectives in vestibular diagnostics and therapy  

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Vestibular diagnostics and therapy ist the mirror of technological, scientific and socio-economics trends as are other fields of clinical medicine. These trends have led to a substantial diversification of the field of neurotology.The improvements in diagnostics have been characterized by the introd...

Ernst, A

214

Perspectives in vestibular diagnostics and therapy [  

Directory of Open Access Journals (Sweden)

Full Text Available [english] Vestibular diagnostics and therapy ist the mirror of technological, scientific and socio-economics trends as are other fields of clinical medicine. These trends have led to a substantial diversification of the field of neurotology.The improvements in diagnostics have been characterized by the introduction of new receptor testing tools (e.g., VEMPs), progress in imaging (e.g., the endolymphatic hydrops) and in the description of central-vestibular neuroplasticity. The etiopathology of vestibular disorders has been updated by geneticists (e.g., the description of the COCH gene mutations), the detection of structural abnormalities (e.g., dehiscence syndromes) and related disorders (e.g. migraine-associated vertigo). The therapeutic options were extended by re-evaluation of techniques known a long time ago (e.g., saccus exposure), the development of new approaches (e.g., dehiscence repair) and the introduction of new drug therapy concepts (e.g., local drug delivery). Implantable, neuroprosthetic solutions have not yet reached experimental safety and validity and are still far away. However, externally worn neuroprosthetic solution were introduced in the rehab of vestibular disorders (e.g., VertiGuard system).These and related trends point into a medical future which is characterized by presbyvertigo as classical sign of the demographic changes ahead, by shortage of financial resources and a medico-legally over-regulated, even hostile environment for physicians in clinical medicine.

Ernst, Arneborg

2012-01-01

215

What does galvanic vestibular stimulation stimulate?  

UK PubMed Central (United Kingdom)

The technique of galvanic vestibular stimulation (GVS) has been used for a long time. The stimulus produces stereotyped automatic postural and ocular responses. The mechanisms underlying these responses are not understood although they are commonly attributed to altered otolith output. Based on animal studies, it seems reasonable to assume that vestibular afferents from the otoliths and semicircular canals are affected similarly by GVS. With this assumption, and anatomical knowledge of the vestibular apparatus, a model is developed to describe the expected responses of vestibular afferents to percutaneous GVS and the physiological implications of this altered sensory signal. Bilateral bipolar GVS, the most commonly used technique, should produce a canal signal consistent with a strong ear-down roll towards the cathodal side, a smaller nose-to-cathode yaw, but no pitch signal. Bilateral bipolar GVS should also produce an otolith signal consistent with tilt towards the cathodal side or a translational acceleration towards the anodal side. The expected responses for other configurations of GVS are also described. The model appears consistent with published data on the ocular and postural responses to GVS, and suggests other testable hypotheses concerning postural, ocular and perceptual responses to GVS.

Wardman DL; Fitzpatrick RC

2002-01-01

216

Assessing vestibular function: which tests, when?  

UK PubMed Central (United Kingdom)

Vertigo and dizziness are common complaints encountered in clinical practice. The patient's history and a thorough otoneurological evaluation are essential for identifying the specific pathology behind the patient's complaints. If the patient reports an illusion of movement (vertigo), this most likely indicates an imbalance within the vestibular system. A sensation of rotatory movement together with a spontaneous nystagmus suggests a lesion involving the semicircular canals, while an illusion of linear movement indicates a disturbance of the otoliths. Nystagmus of central origin or caused by a peripheral vestibular lesion can usually be distinguished by other features in the history or on clinical examination. While peripheral vestibular lesions usually lead to a mixed horizontal-torsional or vertical-torsional nystagmus, a pure vertical or pure torsional nystagmus is always caused by a central lesion. With simple bedside tests such as head-shaking nystagmus and rapid head impulses deficits in labyrinthine function can clearly be detected. For a more thorough investigation of vestibular function at the level of individual semicircular canals and the otoliths, modern techniques are now available such as three-dimensional eye movement vector analysis for the evaluation of individual semicircular canal function, measurement of the subjective visual vertical for utricular, and click-evoked myogenic potentials for saccular testing.

Fetter M

2000-05-01

217

Response to Vestibular Sensory Events in Autism  

Science.gov (United States)

The purpose of this study was to examine the response to vestibular sensory events in persons with autism. The data for this study was collected as part of a cross-sectional study that examined sensory processing (using the Sensory Profile) in 103 persons with autism, 3-43 years of age, compared to age- and gender-matched community controls. The…

Kern, Janet K.; Garver, Carolyn R.; Grannemann, Bruce D.; Trivedi, Madhukar H.; Carmody, Thomas; Andrews, Alonzo A.; Mehta, Jyutika A.

2007-01-01

218

Gamma knife radiosurgery for vestibular schwannomas.  

Science.gov (United States)

The purpose of this study was to analyze tumor control and possible complications of gamma knife radiosurgery (GKRS) in patients with vestibular schwannomas using low marginal doses and conformal multiple shots to fit irregular tumor shapes. The authors evaluated 152 patients with more than 5 years of follow-up. Marginal doses were 9-15 Gy (median 12 Gy), with corresponding treatment volumes ranging from 0.1 to 18.7 cm3 (median 2.0 cm3). The number of isocenters varied from 2 to 24 shots (median 9 shots). The actuarial tumor control rates were 94% at 5 years and 92.4% at 8 years. Larger tumors (p stabilometry as well as neurological examinations to evaluate vestibular function in detail, both before and after GKRS. The results revealed 90% of the patients to have already developed vestibular dysfunction prior to the treatment despite reported symptoms of dizziness. GKRS did not significantly affect vestibular function. Hydrocephalus was recognized in 5.3% of all patients, and tended to occur in cases with larger tumors (p = 0.0024). GKRS provides a safe and effective therapy for small to medium-sized tumors. However, indications for larger tumors must be carefully considered, as they are more difficult to control and liable to produce ataxia due to transient expansion. PMID:18948719

Fukuoka, Seiji; Takanashi, Masami; Hojyo, Atsufumi; Konishi, Masanori; Tanaka, Chiharu; Nakamura, Hirohiko

2009-01-01

219

[Vestibular system in patients with systemic sclerosis].  

UK PubMed Central (United Kingdom)

OBJECTIVES: In systemic sclerosis (SSc) there may occur hearing and balance disorders as a result of the immune-mediated inner ear damage, the etiology being vasculitis and fibrosis. The objective is the vestibular organ evaluation in patients with SSc regarding their prevalence and relationship to duration of the disease and Raynaud phenomenon and also to type and severity of SSc. MATERIAL: Twenty unselected, consecutive patients with diagnosed SSc, complying with international diagnostic criteria of the American Rheumatism Association (1982), were enrolled into the study. The control group consisted of 26 otologically healthy persons matched to the SSc group for age and sex. METHODS: In all patients the questionnaire about audiovestibular history, otolaryngological examination, static and dynamic vestibular tests and the electronystsgmography (ENG) were performed. The patients were investigated with the electronystsgmography (ENG) for spontaneous, positional and caloric-induced nystagmus. Also visual ocular-motor tests were performer. RESULTS: In the anamnesis 65% of patients reported vertigo, 55% - headaches, 50% - tinnitus, 40% - hyperacusis, 40% - hearing loss and 30% - ear fullness. Vertigo, dizziness balance disturbance and uncorrect results of Romberg and Utenberger tests were more frequent in patients with vestibular organ lesion. Abnormalities in vestibular organ in SSc patients were fund in 14 (70%) persons - the central type of lesion - 8 (40%), mixed type in 3 (15%) and peripheral in 3 (15%). CONCLUSIONS: Ear involvement is frequent in systemic sclerosis and should be taken into consideration during diagnostic and therapeutic procedures.

Maciaszczyk K; Durko T; Waszczykowska E; Bartkowiak-Dziankowska B; Pajor A; Erkiert-Polguj A; Józefowicz-Korczy?ska M

2011-05-01

220

Perspectives in vestibular diagnostics and therapy [  

Digital Repository Infrastructure Vision for European Research (DRIVER)

[english] Vestibular diagnostics and therapy ist the mirror of technological, scientific and socio-economics trends as are other fields of clinical medicine. These trends have led to a substantial diversification of the field of neurotology.The improvements in diagnostics have been characterized by ...

Ernst, Arneborg

 
 
 
 
221

Vestibular effects on cerebral blood flow  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Humans demonstrate a number of unique adaptations that allow for the maintenance of blood pressure and brain blood flow when upright. While several physiological systems, including cerebral autoregulation, are involved in this adaptation the unique role the vestibular system plays in helping to maintain brain blood flow is just beginning to be elucidated. In this study, we tested the hypothesis that stimulation of the vestibular system, specifically the otoliths organs, would result in changes in cerebral blood flow. Results To test our hypothesis, we stimulated the vestibular organs of 25 healthy subjects by pitch tilt (stimulates both canals and otoliths) and by translation on a centrifuge (stimulates otoliths and not the canals) at five frequencies: 0.5, 0.25, 0.125 and 0.0625 Hz for 80 sec and 0.03125 Hz for 160 sec. Changes in cerebral flow velocity (by transcranial Doppler) and blood pressure (by Finapres) were similar during both stimuli and dependent on frequency of stimulation (P 2. Conclusion The experimental results support our hypothesis and provide evidence that activation of the vestibular apparatus, specifically the otolith organs, directly affects cerebral blood flow regulation, independent of blood pressure and end tidal CO2 changes.

Serrador Jorge M; Schlegel Todd T; Black F Owen; Wood Scott J

2009-01-01

222

Migraine associated with auditory-vestibular dysfunction.  

UK PubMed Central (United Kingdom)

UNLABELLED: The association between hearing and balance disorders with migraine is known since the times of the ancient Greeks, when Aretaeus from Cappadocia in 131 B.C, made an accurate and detailed description of this occurrence during a migraine episode. We present a broad review of migraine neurotological manifestations, using the most recent publications associated with epidemiology, clinical presentation, pathophysiology, diagnostic methods and treatment for this syndrome. AIM: To describe the clinical entity: "Migraine associated with auditory-vestibular dysfunction" in order to help otorhinolaryngologists and neurologists in the diagnosis and management of such disorder. FINAL REMARKS: There is a strong association between neurotological symptoms and migraine, and the auditory-vestibular dysfunction-associated migraine is the most common cause of spontaneous episodic vertigo (non-positional). Symptoms may vary broadly among patients, making it a diagnostic challenge to the otorhinolaryngologist. This entity usually presents with positional or spontaneous vertigo spells, lasting for seconds or days, associated with migraine symptoms. A better understanding of the relationship between central vestibular mechanisms and migraine mechanisms, besides the discovery of ionic channel disorders in some cases of migraine, ataxia and vertigo, may lead to a better understanding of migraine pathophysiology associated with audio-vestibular disorder.

Cal R; Bahmad Jr F

2008-07-01

223

Vestibular characterization in the menstrual cycle/ Caracterização vestibular no ciclo menstrual  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese 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 audi? (more) ?ão 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 a presença de diferença estatisticamente significante no ciclo ovariano somente para as provas do exame vestibular de calibração, movimentos sacádicos, prova rotatória pendular decrescente e prova calórica. As variáveis: idade, ciclo menstrual regulado, casos de surdez ou tontura na família, doenças anteriores, e sintomas do período pré-menstrual como zumbido, cefaleia, distúrbio do sono, ansiedade, náusea e hiperacusia também podem interferir no exame otoneurológico. CONCLUSÃO: Há diferenças nos resultados do exame vestibular em mulheres sadias entre os períodos pré e pós menstrual. Abstract in english 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 com (more) plaints. 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.

Ishii, Cintia; Nishino, Lucia Kazuko; Campos, Carlos Alberto Herrerias de

2009-06-01

224

Vestibular characterization in the menstrual cycle Caracterização vestibular no ciclo menstrual  

Directory of Open Access Journals (Sweden)

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 a presença de diferença estatisticamente significante no ciclo ovariano somente para as provas do exame vestibular de calibração, movimentos sacádicos, prova rotatória pendular decrescente e prova calórica. As variáveis: idade, ciclo menstrual regulado, casos de surdez ou tontura na família, doenças anteriores, e sintomas do período pré-menstrual como zumbido, cefaleia, distúrbio do sono, ansiedade, náusea e hiperacusia também podem interferir no exame otoneurológico. CONCLUSÃO: Há diferenças nos resultados do exame vestibular em mulheres sadias entre os períodos pré e pós menstrual.

Cintia Ishii; Lucia Kazuko Nishino; Carlos Alberto Herrerias de Campos

2009-01-01

225

Morphologically mixed chemical-electrical synapses formed by primary afferents in rodent vestibular nuclei as revealed by immunofluorescence detection of connexin36 and vesicular glutamate transporter-1.  

Science.gov (United States)

Axon terminals forming mixed chemical/electrical synapses in the lateral vestibular nucleus of rat were described over 40years ago. Because gap junctions formed by connexins are the morphological correlate of electrical synapses, and with demonstrations of widespread expression of the gap junction protein connexin36 (Cx36) in neurons, we investigated the distribution and cellular localization of electrical synapses in the adult and developing rodent vestibular nuclear complex, using immunofluorescence detection of Cx36 as a marker for these synapses. In addition, we examined Cx36 localization in relation to that of the nerve terminal marker vesicular glutamate transporter-1 (vglut-1). An abundance of immunolabeling for Cx36 in the form of Cx36-puncta was found in each of the four major vestibular nuclei of adult rat and mouse. Immunolabeling was associated with somata and initial dendrites of medium and large neurons, and was absent in vestibular nuclei of Cx36 knockout mice. Cx36-puncta were seen either dispersed or aggregated into clusters on the surface of neurons, and were never found to occur intracellularly. Nearly all Cx36-puncta were localized to large nerve terminals immunolabeled for vglut-1. These terminals and their associated Cx36-puncta were substantially depleted after labyrinthectomy. Developmentally, labeling for Cx36 was already present in the vestibular nuclei at postnatal day 5, where it was only partially co-localized with vglut-1, and did not become fully associated with vglut-1-positive terminals until postnatal day 20-25. The results show that vglut-1-positive primary afferent nerve terminals form mixed synapses throughout the vestibular nuclear complex, that the gap junction component of these synapses contains Cx36, that multiple Cx36-containing gap junctions are associated with individual vglut-1 terminals and that the development of these mixed synapses is protracted over several postnatal weeks. PMID:23912039

Nagy, J I; Bautista, W; Blakley, B; Rash, J E

2013-07-31

226

Compensation of postural reactions to free-fall in the vestibular neurectomized monkey. Role of the visual motions cues.  

UK PubMed Central (United Kingdom)

In previous studies a contribution of vision to vestibular-dependent muscle responses during free-fall was found in the intact monkey, and the role of remaining labyrinthine afferents in compensation of these postural reactions was studied in vestibular neurectomized monkeys. In the present investigation we have compared the role of visual motion cues in the recovery of muscle responses to fall in unilateral (U.N.) and bilateral vestibular neurectomized (B.N.) baboons. During free-fall, electromyographic (EMG) responses were recorded from splenius capitis, soleus and tibialis anterior muscles. EMG activities were recorded in two randomly presented conditions: with normal motion of the visual world (NV) and with the visual world stabilized with respect to the baboon's head (SV) until 6 weeks after surgery. In B.N. baboons, results showed that condition SV was accompanied by a very strong motor depression during the entire test period. A greater decrease was observed in the splenius and soleus muscles. In U.N. baboons, significantly depressed EMG responses were recorded in the SV condition during the first two stages of compensation only (0--2 weeks), in all tested muscles except the tibialis anterior muscle. On the other hand, these motor depressions appeared to depend upon the level of neuronal resting activity in the vestibular nuclei. It is inferred that the partial recovery of muscle responses to fall observed in B.N. baboons in the NV condition is mainly due to visual information concerning motion, which replaces to the labyrinthine afferents. In U.N. baboons, the visual motion cues would fulfil only a transitory substitution function by supplying the decrease of neuronal activity in the vestibular nuclei. Later on, full compensation would be carried out by means of the remaining labyrinth.

Lacour M; Xerri C

1980-01-01

227

Vestibular function and quality of life in vestibular schwannoma: does size matter?  

UK PubMed Central (United Kingdom)

Objectives: Patients with vestibular schwannoma (VS) frequently suffer from disabling vestibular symptoms. This prospective follow-up study evaluates vestibular and auditory function and impairment of quality of life due to vertigo, dizziness, and imbalance in patients with unilateral VS of different sizes before/after microsurgical or radiosurgical treatment. Methods: Thirty-eight patients with unilateral VS were included. Twenty-two received microsurgery, 16 CyberKnife radiosurgery. Two follow-ups took place after a median of 50 and 186.5?days. Patients received a standardized neuro-ophthalmological examination, electronystagmography with bithermal caloric testing, and pure-tone audiometry. Quality of life was evaluated with the Dizziness Handicap Inventory (DHI). Patient data was grouped and analyzed according to the size of the VS (group 1: <20?mm vs group 2: ?20?mm). Results: In group 1, the median loss of vestibular function was +10.5% as calculated by Jongkees Formula (range -43 to +52; group 2: median +36%, range -56 to +90). The median change of DHI scores was -9 in group 1 (range -68 to 30) and +2 in group 2 (-54;+20). Median loss of hearing was 4?dB (-42; 93) in group 1 and 12?dB in group 2 (5; 42). Conclusion: Loss of vestibular function in VS clearly correlates with tumor size. However, loss of vestibular function was not strictly associated with a long-term deterioration of quality of life. This may be due to central compensation of vestibular deficits in long-standing large tumors. Loss of hearing before treatment was significantly influenced by the age of the patient but not by tumor size. At follow-up 1 and 2, hearing was significantly influenced by the size of the VS and the manner of treatment.

Wagner JN; Glaser M; Wowra B; Muacevic A; Goldbrunner R; Cnyrim C; Tonn JC; Strupp M

2011-01-01

228

Descripción, interpretación, análisis e importancia del nistagmus inducido por la hiperventilación en el estudio de patologías vestibulares periféricas y centrales Description, interpretation, analysis and importance of hyperventilation -induced nystagmus in the study of the peripheral and central vestibular disorders  

Directory of Open Access Journals (Sweden)

Full Text Available Recientes estudios clínicos han revelado la utilidad del test del nistagmus inducido por la hiperventilación aguda, en la investigación de patologías vestibulares retrolaberínticas, neurales y de origen central, con la aparición de nistagmus paréticos o bien excitatorios. El propósito de este estudio ha sido: primero, conocer la sensibilidad de este examen según el análisis de los estudios de diferentes autores; segundo, entender la fisiopatología de este nistagmus inducido por la hiperventilación y tercero, efectuar una interpretación y análisis de este examen que permita obtener conclusiones sólidas del mejor nivel de medicina basada en evidencias. Para efectuar este estudio y análisis se procedió a una investigación exhaustiva de las publicaciones sobre el tema en los últimos 25 años, recurriendo para ello como fuentes de información a las principales bases de datos biomédicos y a la revisión en texto completo de estas publicaciones. Llamó la atención la escasez de trabajos clínicos publicados sobre el tema que no superan los 40, y también la escasez de trabajos sobre la fisiopatología del nistagmus inducido por la hiperventilación aguda. La metódica del test es muy simple por lo que su utilización resulta muy atractiva, con un escaso número de falsos positivos. La mayor parte de los estudios publicados, se focaliza en su utilización en el schwanoma vestibularyen la neuronitis vestibular. Respecto al schwanoma vestibular de un total de 107 pacientes estudiados el test fue positivo en el 80% de los casos, con aparición de nistagmus ipsilesional o contralesional. En la neuronitis vestibular la positividad del test alcanzó a 60°% de un total de 272 pacientes estudiados y que estaba en relación directa con el tiempo de evolución de la enfermedad. En la esclerosis múltiple, en pacientes con síntomas vestibulares, la positividad del test fue de 75°%, en cambio en aquellos pacientes sin síntomas vestibulares la positividad fue de sólo 7°%. En las enfermedades cerebelosas, particularmente las degenerativas, la positividad de este test fue de 78°%. La pesquisa del nistagmus inducido por la hiperventilación, fue una prueba poco significativa estadísticamente, en otras patologías vestibulares períféricas tales como la enfermedad de Ménière o el VPPB, así como en otras enfermedades vestibulares centrales, salvo las de origen vascular por insuficiencia del sistema vértebro-basilar. El estudio y análisis de las publicaciones sobre el nistagmus inducido por la hiperventilación aguda, permite concluir que es un test de fácil realización; que ante la sospecha de un schwanoma vestibular, orienta en el estudio de aquellos pacientes que requieran un estudio de R.M. Que ayuda en el diagnóstico diferencial de una neuronitisvestibular y finalmente que permite en lesiones vestibulares centrales particularmente degenerativas y vasculares un estudio más profundo y adecuado de estos pacientes.Recent clinical studies have revealed the usefulness of the hyperventilation-induced nystagmus in retrolabyrinthine and central vestibular diseases with the appearance either excitatory (ipsilateral) or paretic (contralateral) nystagmus. The objectives of this study have been: 1) to get to know the sensitivity of the exam, according to the best literature available; 2) to get to know the physiopathology of this hyperventilation-induced nystagmus, and 3) to carry out an analysis and interpretation of this exam in order to reach solid conclusions of the highest level in evidence based medicine. An exhaustive research of literature published on this topic in the last 25 years was carried out. The main source of information being the most important medical data-based publications and also a thorough revision of these texts. The scarce number of publications on this topic (not more than 40) is what strikes the attention most, as well as the very few studies of the physiopathology of the hyperventilation-induced nystagmus. The method of the test is a simple one; this fact makes its a

Alejandro Peña M

2012-01-01

229

Descripción, interpretación, análisis e importancia del nistagmus inducido por la hiperventilación en el estudio de patologías vestibulares periféricas y centrales/ Description, interpretation, analysis and importance of hyperventilation -induced nystagmus in the study of the peripheral and central vestibular disorders  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Recientes estudios clínicos han revelado la utilidad del test del nistagmus inducido por la hiperventilación aguda, en la investigación de patologías vestibulares retrolaberínticas, neurales y de origen central, con la aparición de nistagmus paréticos o bien excitatorios. El propósito de este estudio ha sido: primero, conocer la sensibilidad de este examen según el análisis de los estudios de diferentes autores; segundo, entender la fisiopatología de este nista (more) gmus inducido por la hiperventilación y tercero, efectuar una interpretación y análisis de este examen que permita obtener conclusiones sólidas del mejor nivel de medicina basada en evidencias. Para efectuar este estudio y análisis se procedió a una investigación exhaustiva de las publicaciones sobre el tema en los últimos 25 años, recurriendo para ello como fuentes de información a las principales bases de datos biomédicos y a la revisión en texto completo de estas publicaciones. Llamó la atención la escasez de trabajos clínicos publicados sobre el tema que no superan los 40, y también la escasez de trabajos sobre la fisiopatología del nistagmus inducido por la hiperventilación aguda. La metódica del test es muy simple por lo que su utilización resulta muy atractiva, con un escaso número de falsos positivos. La mayor parte de los estudios publicados, se focaliza en su utilización en el schwanoma vestibularyen la neuronitis vestibular. Respecto al schwanoma vestibular de un total de 107 pacientes estudiados el test fue positivo en el 80% de los casos, con aparición de nistagmus ipsilesional o contralesional. En la neuronitis vestibular la positividad del test alcanzó a 60°% de un total de 272 pacientes estudiados y que estaba en relación directa con el tiempo de evolución de la enfermedad. En la esclerosis múltiple, en pacientes con síntomas vestibulares, la positividad del test fue de 75°%, en cambio en aquellos pacientes sin síntomas vestibulares la positividad fue de sólo 7°%. En las enfermedades cerebelosas, particularmente las degenerativas, la positividad de este test fue de 78°%. La pesquisa del nistagmus inducido por la hiperventilación, fue una prueba poco significativa estadísticamente, en otras patologías vestibulares períféricas tales como la enfermedad de Ménière o el VPPB, así como en otras enfermedades vestibulares centrales, salvo las de origen vascular por insuficiencia del sistema vértebro-basilar. El estudio y análisis de las publicaciones sobre el nistagmus inducido por la hiperventilación aguda, permite concluir que es un test de fácil realización; que ante la sospecha de un schwanoma vestibular, orienta en el estudio de aquellos pacientes que requieran un estudio de R.M. Que ayuda en el diagnóstico diferencial de una neuronitisvestibular y finalmente que permite en lesiones vestibulares centrales particularmente degenerativas y vasculares un estudio más profundo y adecuado de estos pacientes. Abstract in english Recent clinical studies have revealed the usefulness of the hyperventilation-induced nystagmus in retrolabyrinthine and central vestibular diseases with the appearance either excitatory (ipsilateral) or paretic (contralateral) nystagmus. The objectives of this study have been: 1) to get to know the sensitivity of the exam, according to the best literature available; 2) to get to know the physiopathology of this hyperventilation-induced nystagmus, and 3) to carry out an an (more) alysis and interpretation of this exam in order to reach solid conclusions of the highest level in evidence based medicine. An exhaustive research of literature published on this topic in the last 25 years was carried out. The main source of information being the most important medical data-based publications and also a thorough revision of these texts. The scarce number of publications on this topic (not more than 40) is what strikes the attention most, as well as the very few studies of the physiopathology of the hyperventilation-induced nystagmus. The

Peña M, Alejandro

2012-04-01

230

Swimming Behavior and Calcium Incorporation into inner Ear Otoliths of Fish after vestibular Nerve Transection  

Science.gov (United States)

Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium-tracer alizarin- complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated: Like neonate swordtails, type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal and the otolithic calcium incorporation in controls of the same batch was symmetrical. In type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetrical. These results stongly suggest that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. Thus, it is assumed that the mechanisms regulating otolith growth and equlibibrium differ in the two types of cichlid fish. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

Edelmann, E.; Anken, R.; Rahmann, H.

231

78 FR 53700 - Revised Medical Criteria for Evaluating Hearing Loss and Disturbances of Labyrinthine-Vestibular...  

Science.gov (United States)

...Loss and Disturbances of Labyrinthine-Vestibular Function AGENCY: Social Security Administration...loss and disturbances of labyrinthine-vestibular function in adults and children. We...loss and disturbances of labyrinthine-vestibular function. We last published final...

2013-08-30

232

El examen vestibular abreviado, descripción, interpretación y análisis/ The abbreviated vestibular exam, description, interpretation and analysis  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Introducción: En el examen vestibular de un paciente vertiginoso juegan un rol muy importante las pruebas calóricas, pero la realización de éstas, unida a las nuevas pruebas que ha traído el avance tecnológico y computacional de la medicina, ha significado que el examen vestibular se ha convertido en la práctica diaria en un estudio muy largo y oneroso, por tal motivo parece útil la realización de un examen vestibular abreviado preliminar hecho en la misma consul (more) ta del médico que permita dar una orientación diagnóstica de bases sólidas. Objetivos: El propósito de este estudio es la descripción, interpretación y análisis crítico del llamado "examen vestibular de 10 minutos del paciente mareado"y que permita llegar a conclusiones sobre la sensibilidad y especificidad de este examen abreviado. Material y método: En este estudio, se describen, interpretan y analizan, según la información bibliográfica disponible, particularmente aquellos estudios de la medicina basada en evidencias las siguientes pruebas propuestas en el examen vestibular abreviado: Búsqueda del nistagmus espontáneo, búsqueda del nistagmus de mirada excéntrica, estudio de los movimientos oculares lentos o de rastreo ocular, estudio de los movimientos oculares rápidos o sacadas, test de Halmagyi, test de agitación cefálica, test de agudeza visual dinámica, test de inhibición de la fijación del nistagmus, maniobra de Dix y Hallpike, test de otoscopía neumática, estudio cerebeloso, estudio de la sensibilidad profunda, prueba de Romberg y estudio de la marcha. Debido a que varias de estas pruebas se efectúan en la prueba vestibular clásica sólo se analizan y discuten aquellas que no se efectúan de rutina en este examen. Resultados: Las pruebas analizadas del examen vestibular abreviado revelan en su gran mayoría baja sensibilidad, menor de 50%, pero una buena especificidad. Con algún entrenamiento básico son fáciles de realizar y requieren poco tiempo para su ejecución pero sí, mucho más que 10 minutos. Discusión: Considerando el largo tiempo que requiere el especialista para efectuar un examen vestibular completo, un estudio básico resulta necesario para orientar la investigación clínica de un paciente vertiginoso. Las pruebas propuestas en este examen, tienen baja sensibilidad consideradas individualmente, pero la realización de todas ellas en su conjunto, le confiere al estudio una gran fortaleza y credibilidad, esto necesariamente unido a una muy buena anamnesis con cuestionario estructurado preestablecido. Conclusiones: El examen vestibular abreviado es un buen estudio, en que si bien las diferentes pruebas tienen baja sensibilidad, el resultado de la suma de todas ellas le confiere al examen una buena confiabilidad. Para su realización es indispensable un buen manejo de las pruebas y un buen conocimiento de la otoneurología por parte del examinador para su correcta interpretación. No existen estudios de medicina basada en evidencias de nivel 1 ó 2 que le otorguen alta credibilidad a estas pruebas. Este examen no debe reemplazar al examen vestibular clásico o formal, incluyendo las pruebas calóricas bi-termales, sino que deben ser consideradas como un estudio básico que permite orientar al especialista para tomar decisiones apropiadas diagnósticas y terapéuticas. Abstract in english Introduction: Caloric tests play a very important role in a patient's vestibular exam. But these exams, along with the new test brought about by both technology and computing in Medicine, have turned these examinations into very long and expensive procedures. Taking all this into account, it seems suitable the realization of a preliminary vestibular exam performed in the doctor's consultation office. This will allow a diagnostic guideline with solid foundations. Aim: To d (more) escribe, interpret, and carry out a critical analysis of the so called "10 minute vestibular examination of the dizzy patient" in order to get to some conclusions about sensitivity and specificity o

Peña M, Alejandro

2011-08-01

233

El examen vestibular abreviado, descripción, interpretación y análisis The abbreviated vestibular exam, description, interpretation and analysis  

Directory of Open Access Journals (Sweden)

Full Text Available Introducción: En el examen vestibular de un paciente vertiginoso juegan un rol muy importante las pruebas calóricas, pero la realización de éstas, unida a las nuevas pruebas que ha traído el avance tecnológico y computacional de la medicina, ha significado que el examen vestibular se ha convertido en la práctica diaria en un estudio muy largo y oneroso, por tal motivo parece útil la realización de un examen vestibular abreviado preliminar hecho en la misma consulta del médico que permita dar una orientación diagnóstica de bases sólidas. Objetivos: El propósito de este estudio es la descripción, interpretación y análisis crítico del llamado "examen vestibular de 10 minutos del paciente mareado"y que permita llegar a conclusiones sobre la sensibilidad y especificidad de este examen abreviado. Material y método: En este estudio, se describen, interpretan y analizan, según la información bibliográfica disponible, particularmente aquellos estudios de la medicina basada en evidencias las siguientes pruebas propuestas en el examen vestibular abreviado: Búsqueda del nistagmus espontáneo, búsqueda del nistagmus de mirada excéntrica, estudio de los movimientos oculares lentos o de rastreo ocular, estudio de los movimientos oculares rápidos o sacadas, test de Halmagyi, test de agitación cefálica, test de agudeza visual dinámica, test de inhibición de la fijación del nistagmus, maniobra de Dix y Hallpike, test de otoscopía neumática, estudio cerebeloso, estudio de la sensibilidad profunda, prueba de Romberg y estudio de la marcha. Debido a que varias de estas pruebas se efectúan en la prueba vestibular clásica sólo se analizan y discuten aquellas que no se efectúan de rutina en este examen. Resultados: Las pruebas analizadas del examen vestibular abreviado revelan en su gran mayoría baja sensibilidad, menor de 50%, pero una buena especificidad. Con algún entrenamiento básico son fáciles de realizar y requieren poco tiempo para su ejecución pero sí, mucho más que 10 minutos. Discusión: Considerando el largo tiempo que requiere el especialista para efectuar un examen vestibular completo, un estudio básico resulta necesario para orientar la investigación clínica de un paciente vertiginoso. Las pruebas propuestas en este examen, tienen baja sensibilidad consideradas individualmente, pero la realización de todas ellas en su conjunto, le confiere al estudio una gran fortaleza y credibilidad, esto necesariamente unido a una muy buena anamnesis con cuestionario estructurado preestablecido. Conclusiones: El examen vestibular abreviado es un buen estudio, en que si bien las diferentes pruebas tienen baja sensibilidad, el resultado de la suma de todas ellas le confiere al examen una buena confiabilidad. Para su realización es indispensable un buen manejo de las pruebas y un buen conocimiento de la otoneurología por parte del examinador para su correcta interpretación. No existen estudios de medicina basada en evidencias de nivel 1 ó 2 que le otorguen alta credibilidad a estas pruebas. Este examen no debe reemplazar al examen vestibular clásico o formal, incluyendo las pruebas calóricas bi-termales, sino que deben ser consideradas como un estudio básico que permite orientar al especialista para tomar decisiones apropiadas diagnósticas y terapéuticas.Introduction: Caloric tests play a very important role in a patient's vestibular exam. But these exams, along with the new test brought about by both technology and computing in Medicine, have turned these examinations into very long and expensive procedures. Taking all this into account, it seems suitable the realization of a preliminary vestibular exam performed in the doctor's consultation office. This will allow a diagnostic guideline with solid foundations. Aim: To describe, interpret, and carry out a critical analysis of the so called "10 minute vestibular examination of the dizzy patient" in order to get to some conclusions about sensitivity and specificity of this short exam. Material and method: Using the availab

Alejandro Peña M

2011-01-01

234

Asymmetry of balance responses to monaural galvanic vestibular stimulation in subjects with vestibular schwannoma?  

Science.gov (United States)

Objective We investigated the potential of galvanic vestibular stimulation (GVS) to quantify lateralised asymmetry of the vestibulospinal pathways by measuring balance responses to monaural GVS in 10 subjects with vestibular schwannoma and 22 healthy control subjects. Methods Subjects standing without vision were stimulated with 3 s, 1 mA direct current stimuli delivered monaurally. The mean magnitude and direction of the evoked balance responses in the horizontal plane were measured from ground-reaction forces and from displacement and velocity of the trunk. Vestibular-evoked myogenic potentials (VEMPs) to 500 Hz air and bone-conducted tones were also recorded. Results In healthy subjects, the magnitudes of the force, velocity and displacement responses were not significantly different for left compared to right ear stimulation. Their individual asymmetry ratios were always vestibular schwannoma had significantly smaller force, velocity and displacement responses to stimulation of the affected compared with non-affected ear. Their mean asymmetry ratios were significantly elevated for all three measures (41.2 ± 10.3%, 40.3 ± 15.1% and 21.9 ± 14.6%). Conclusions Asymmetry ratios of balance responses to monaural GVS provide a quantitative and clinically applicable lateralising test of the vestibulospinal pathways. Significance This method offers a more clinically relevant measure of standing balance than existing vestibular function tests which assess only vestibuloocular and vestibulocollic pathways.

Welgampola, Miriam S.; Ramsay, Elijane; Gleeson, Michael J.; Day, Brian L.

2013-01-01

235

Correlation between vestibular test results and self-reported psychological complaints of patients with vestibular symptoms.  

UK PubMed Central (United Kingdom)

UNLABELLED: Cognitive and emotional factors may affect balance; psychiatric conditions are a common component in patient dizziness. The treatment of patients with vertigo may be affected to a greater degree by the suffering due to this disease than by the severity of organic changes. OBJECTIVE: This study aimed to investigate associations between vestibular test results and self-reported psychological complaints in patients evaluated during 2009 in an audiology unit at a hospital in Porto Alegre. METHODS: We conducted a retrospective, descriptive-exploratory study of data taken from a database of the software VecWin® and VecWin® 2, developed by Neurograff®. We investigated vestibular test results, reports of psychological symptoms reported spontaneously, and information such as age, sex and the presence of vertigo and/or dizziness. This study consisted of three steps: clustering, exclusion/inclusion and quantification. CONCLUSION: Age and gender and the presence or absence of vertigo and/or dizziness were not variables that influenced the outcomes of vestibular testing. There was a significant association between the presence of self-reported psychological complaints and normal vestibular test results. Thus, it is crucial that professionals pay attention to psychological issues reported by patients when the vestibular history is taken.

Gurgel LG; Dourado MR; Moreira Tde C; Serafini AJ; Menegotto IH; Reppold CT; Soldera CL

2012-02-01

236

The Application of Rotatory Chair for Evaluating Some Vestibular Pathology  

Directory of Open Access Journals (Sweden)

Full Text Available Adaptability of the vestibular system to repetition of the movements of rotatory chair is one of the disadvantages of this experiment. Besides the procedure is disturbing and cause intense reactions in high acceleration. By the way, advantages such as big deal of information provided about the function of peripheral and central vestibular system prevent us ignoring this special test. In this article the procedure is explained and its application in distinguishing different pathologies of vestibular system is discussed in brief.

Laya Postforoush Bataghva

1996-01-01

237

[Differential diagnostics of peripheral vestibular and brainstem-cerebellar syndrome].  

UK PubMed Central (United Kingdom)

The objective of the present study was to develop criteria for differential diagnostics of peripheral vestibular and brainstem-cerebellar syndrome based on the analysis of characteristics of evoked vestibular myogenic potentials. A total of 59 patients presenting with unilateral peripheral vestibular syndrome (PVS), 60 patients with demyelinizing disease of CNS, and 20 healthy subjects were available for the examination by the method of evoked vestibular myogenic potentials. The values of representativity and latency parameters PI, N1, PINI and amplitude parameters PI, NI, PINI were obtained. It was shown that latency PI in the patients with demyelinizing disease of CNS is higher than in those with PVS.

Likhachev SA; Tarasevich NM

2013-01-01

238

Inferior vestibular neuritis in a fighter pilot: a case report.  

UK PubMed Central (United Kingdom)

Spatial disorientation in airplane pilots is a leading factor in many fatal flying accidents. Spatial orientation is the product of integrative inputs from the proprioceptive, vestibular, and visual systems. One condition that can lead to sudden pilot incapacitation in flight is vestibular neuritis. Vestibular neuritis is commonly diagnosed by a finding of unilateral vestibular failure, such as a loss of caloric response. However, because caloric response testing reflects the function of only the superior part of the vestibular nerve, it cannot detect cases of neuritis in only the inferior part of the nerve. We describe the case of a Chinese naval command fighter pilot who exhibited symptoms suggestive of vestibular neuritis but whose caloric response test results were normal. Further testing showed a unilateral loss of vestibular evoked myogenic potentials (VEMPs). We believe that this pilot had pure inferior nerve vestibular neuritis. VEMP testing plays a major role in the diagnosis of inferior nerve vestibular neuritis in pilots. We also discuss this issue in terms of aeromedical concerns.

Xie SJ; Jia HB; Xu P; Zheng YJ

2013-06-01

239

Vestibular function in severe bilateral vestibulopathy.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To assess residual vestibular function in patients with severe bilateral vestibulopathy comparing low frequency sinusoidal rotation with the novel technique of random, high acceleration rotation of the whole body. METHODS: Eye movements were recorded by electro-oculography in darkness during passive, whole body sinusoidal yaw rotations at frequencies between 0.05 and 1.6 Hz in four patients who had absent caloric vestibular responses. These were compared with recordings using magnetic search coils during the first 100 ms after onset of whole body yaw rotation at peak accelerations of 2800 degrees /s(2). Off centre rotations added novel information about otolithic function. RESULTS: Sinusoidal yaw rotations at 0.05 Hz, peak velocity 240 degrees/s yielded minimal responses, with gain (eye velocity/head velocity)<0.02, but gain increased and phase decreased at frequencies between 0.2 and 1.6 Hz in a manner resembling the vestibulo-ocular reflex. By contrast, the patients had profoundly attenuated responses to both centred and eccentric high acceleration transients, representing virtually absent responses to this powerful vestibular stimulus. CONCLUSION: The analysis of the early ocular response to random, high acceleration rotation of the whole body disclosed a profound deficit of semicircular canal and otolith function in patients for whom higher frequency sinusoidal testing was only modestly abnormal. This suggests that the high frequency responses during sinusoidal rotation were of extravestibular origin. Contributions from the somatosensory or central predictor mechanisms, might account for the generation of these responses. Random, transient rotation is better suited than steady state rotation for quantifying vestibular function in vestibulopathic patients.

Wiest G; Demer JL; Tian J; Crane BT; Baloh RW

2001-07-01

240

Radiosurgery of residual and recurrent vestibular schwannomas.  

UK PubMed Central (United Kingdom)

Radiosurgery is either a primary or an adjunctive management approach used to treat patients with vestibular schwannomas. We sought to determine outcomes measuring the potential benefits against the neurological risks in patients who underwent radiosurgery after previous microsurgical subtotal resection or recurrence of the tumour after total resection. Gamma Knife radiosurgery was applied as an adjunctive treatment modality for 86 patients with vestibular schwannomas from April 1992 to August 2001. We evaluated the results of 50 patients who had a follow-up of at least 3.5 years (median 75 months, range 42-114 months). In 16 patients a recurrence of disease was observed after previous total resection. The median treatment volume was 3.4 ccm with a median dose to the tumour margin of 13 Gy. Tumour control rate was 96%. Two tumours progressed after adjunctive radiosurgery. Useful hearing (Gardner-Robertson II) (4 patients (8%)) and residual hearing (Gardner-Roberson III) (10 patients (20%)) remained unchanged in all patients, who presented with it before radiosurgery, respectively. Clinical neurological improvement was observed in 24 patients (46%). Adverse effects comprised transient neurological symptoms and signs (incomplete facial palsy, House-Brackman II/III) in five cases (recovered completely), mild trigeminal neuropathy in four cases, and morphological changes displaying rapid enlargement of a pre-existing macrocyst in one patient and tumour growth in another one. No permanent new cranial nerve deficit was observed. Radiosurgery appears to be an effective adjunctive method for growth control of vestibular schwannomas and is associated with both a low mortality rate and a good quality of life. Accordingly, radiosurgery is a rewarding therapeutic approach for the preservation of cranial nerve function in the management of patients with vestibular schwannoma in whom prior microsurgical resection failed.

Unger F; Walch C; Papaefthymiou G; Feichtinger K; Trummer M; Pendl G

2002-07-01

 
 
 
 
241

Gamma knife radiosurgery for vestibular schwannomas.  

UK PubMed Central (United Kingdom)

The purpose of this study was to analyze tumor control and possible complications of gamma knife radiosurgery (GKRS) in patients with vestibular schwannomas using low marginal doses and conformal multiple shots to fit irregular tumor shapes. The authors evaluated 152 patients with more than 5 years of follow-up. Marginal doses were 9-15 Gy (median 12 Gy), with corresponding treatment volumes ranging from 0.1 to 18.7 cm3 (median 2.0 cm3). The number of isocenters varied from 2 to 24 shots (median 9 shots). The actuarial tumor control rates were 94% at 5 years and 92.4% at 8 years. Larger tumors (p < 0.0001) and those in younger patients (p = 0.018) tended to recur significantly more often. Useful hearing, facial and trigeminal functions were preserved at 71, 100 and 97.4%, respectively. Seventeen percent of all patients developed transient dizziness, with dizziness persisting in 2% of the total. Fifty-six other patients not included in the long-term evaluation consecutively underwent caloric testing and static stabilometry as well as neurological examinations to evaluate vestibular function in detail, both before and after GKRS. The results revealed 90% of the patients to have already developed vestibular dysfunction prior to the treatment despite reported symptoms of dizziness. GKRS did not significantly affect vestibular function. Hydrocephalus was recognized in 5.3% of all patients, and tended to occur in cases with larger tumors (p = 0.0024). GKRS provides a safe and effective therapy for small to medium-sized tumors. However, indications for larger tumors must be carefully considered, as they are more difficult to control and liable to produce ataxia due to transient expansion.

Fukuoka S; Takanashi M; Hojyo A; Konishi M; Tanaka C; Nakamura H

2009-01-01

242

Achados vestibulares em pacientes portadores de fibromialgia/ Vestibular findings in fibromyalgia patients  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese INTRODUÇÃO: A fibromialgia (FM) é uma síndrome musculoesquelética não inflamatória, de caráter crônico, de etiologia desconhecida, caracterizada por dor difusa, aumento da sensibilidade na palpação e por sintomas como fadiga, insônia, ansiedade, depressão, intolerância ao frio e queixas otológicas. OBJETIVO: Avaliar o comportamento vestibular em pacientes portadores de fibromialgia. MÉTODO: Foi realizado um estudo retrospectivo de corte transversal. Avalia (more) ram-se 25 pacientes na faixa etária entre 26 e 65 anos (média de idade - 52,2 anos e desvio padrão - 10,3 anos), submetidos aos seguintes procedimentos: anamnese, avaliação otorrinolaringológica e vestibular por meio da vectoeletronistagmografia. RESULTADOS: a) Os sintomas otoneurológicos mais evidenciados foram: dificuldade ou dor ao movimento do pescoço e dor irradiada para ombro ou braço (92,0%) em cada, tontura (84,0%) e cefaleia (76,0%). Os sintomas clínicos diversos mais relatados foram: depressão (80,0%), ansiedade (76,0%) e insônia (72,0%); b) O exame vestibular esteve alterado em 12 pacientes (48,0%) sendo localizado na prova calórica; c) Houve prevalência de alteração no sistema vestibular periférico e, d) Houve predomínio das disfunções vestibulares periféricas deficitárias. CONCLUSÃO: Este estudo permitiu verificar a importância do exame labiríntico o que ressalta que esse tipo de população deveria ser melhor estudada, uma vez que diversas doenças reumatológicas pelas suas manifestações e áreas de comprometimento podem gerar alterações vestibulares importantes. Abstract in english 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 st (more) andard 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.

Zeigelboim, Bianca Simone; Moreira, Denise Nunnes

2011-09-01

243

[Questionnaire for disability assessment in vestibular pathology  

UK PubMed Central (United Kingdom)

The QADVP (questionnaire for assessment of disabled by vestibular pathology) is self-employed and consists of a series of 46 questions divided into 3 scales (emotional, functional and organic) from which direct and proportionate scores (both for each scale and as a whole for the full questionnaire) are gained. The aim of the paper is to show its application-way, the outcome of assessments and the disability degree drawn out from the scores. A prospective study fulfilled within 2 years term (May, 1st 1994 until May, 1st 1996) between patients of the Health Area of Zamora, seen at the ENT outpatients Department. The validation's study (reliability, homogeneity and discriminatory power in each scale and of the whole questionnaire) was made from a sample of 30 patients suffering of recurring-paroxysmal vestibular disease of several etiologies. In order to establish the handicap degree the questionnaire was employed in 60 patients suffering postural-paroxysmal vertigo or Ménière disease, grouped in 4 homogenous sets after the evolutive time. The series in each scale and globally for the whole questionnaire make sharp 4 levels of handicap (from I to IV). Zero degree is equivalent to absence of vestibular disorder. The QADVP is a measuring tool allowing: assessment several degrees of incapacity, to control the development of the disorder and try therapeutic changes.

Pardal Refoyo JL; Beltrán Mateos LD; del Cañizo Alvarez A

1998-01-01

244

[Vestibular and cochlear manifestations in Fabry's disease].  

Science.gov (United States)

Anderson-Fabry's disease corresponds to an inherited disorder transmitted by an X-linked recessive gene. The disease is caused by an alpha-galactosidase deficiency leading to an abnormal glycosphingolipid metabolism, resulting in glycosphingolipids deposits all over the body. The disease affects all organs over the body and can be responsible for central nervous system or renal failure, heart attack, which can lead for early death in absence of diagnosis and treatment. In addition to these life-threatening manifestations, other problems which may have a profound impact on quality of life, such as hearing loss, have been relatively neglected. Thus, a large proportion of patients with Fabry's disease suffer from sensorineural hearing loss, with both progressive hearing impairment and sudden deafness, and peripheral vestibular deficits with dizziness and vertigo. The exact pathophysiologic mechanism(s) of those otological complications is still studied, but both cochleo-vestibular disorder and vascular origin seems to be involved. For many years, only symptomatic treatment has been available. For the past ten years, the introduction of enzyme replacement therapy with recombinant agalsidase-? or -? provides new prospect for these patients, decreasing the risk of complications. Still on study, it may also be active both on hearing loss and vestibular disturbances. PMID:21211674

Malinvaud, D; Germain, D P; Benistan, K; Bonfils, P

2010-12-01

245

[Vestibular and cochlear manifestations in Fabry's disease].  

UK PubMed Central (United Kingdom)

Anderson-Fabry's disease corresponds to an inherited disorder transmitted by an X-linked recessive gene. The disease is caused by an alpha-galactosidase deficiency leading to an abnormal glycosphingolipid metabolism, resulting in glycosphingolipids deposits all over the body. The disease affects all organs over the body and can be responsible for central nervous system or renal failure, heart attack, which can lead for early death in absence of diagnosis and treatment. In addition to these life-threatening manifestations, other problems which may have a profound impact on quality of life, such as hearing loss, have been relatively neglected. Thus, a large proportion of patients with Fabry's disease suffer from sensorineural hearing loss, with both progressive hearing impairment and sudden deafness, and peripheral vestibular deficits with dizziness and vertigo. The exact pathophysiologic mechanism(s) of those otological complications is still studied, but both cochleo-vestibular disorder and vascular origin seems to be involved. For many years, only symptomatic treatment has been available. For the past ten years, the introduction of enzyme replacement therapy with recombinant agalsidase-? or -? provides new prospect for these patients, decreasing the risk of complications. Still on study, it may also be active both on hearing loss and vestibular disturbances.

Malinvaud D; Germain DP; Benistan K; Bonfils P

2010-12-01

246

Radiotherapy for Vestibular Schwannomas: A Critical Review  

International Nuclear Information System (INIS)

Vestibular schwannomas are slow-growing tumors of the myelin-forming cells that cover cranial nerve VIII. The treatment options for patients with vestibular schwannoma include active observation, surgical management, and radiotherapy. However, the optimal treatment choice remains controversial. We have reviewed the available data and summarized the radiotherapeutic options, including single-session stereotactic radiosurgery, fractionated conventional radiotherapy, fractionated stereotactic radiotherapy, and proton beam therapy. The comparisons of the various radiotherapy modalities have been based on single-institution experiences, which have shown excellent tumor control rates of 91-100%. Both stereotactic radiosurgery and fractionated stereotactic radiotherapy have successfully improved cranial nerve V and VII preservation to >95%. The mixed data regarding the ideal hearing preservation therapy, inherent biases in patient selection, and differences in outcome analysis have made the comparison across radiotherapeutic modalities difficult. Early experience using proton therapy for vestibular schwannoma treatment demonstrated local control rates of 84-100% but disappointing hearing preservation rates of 33-42%. Efforts to improve radiotherapy delivery will focus on refined dosimetry with the goal of reducing the dose to the critical structures. As future randomized trials are unlikely, we suggest regimented pre- and post-treatment assessments, including validated evaluations of cranial nerves V, VII, and VIII, and quality of life assessments with long-term prospective follow-up. The results from such trials will enhance the understanding of therapy outcomes and improve our ability to inform patients.

2011-03-15

247

MRI in a quiescent vestibular schwannoma  

International Nuclear Information System (INIS)

Vestibular schwannomas are benign neoplasms that take origin from Schwann cells, the majority arise from the vestibular branch of VIII cranial nerve. Unilateral sensorineural hearing loss is the most common symptom referred by patients who suffer this disease. With the advent and increasing use of MRI the diagnosis of this intra labyrinthine tumor has become more frequent. Paramagnetic contrast gadolinium has precise indication in the study protocol of this pathology. The high sensitivity of this method allows an early diagnosis. In patients with low auditory loss an excision of intra labyrinthine small tumors can offer a better therapeutic chance. We report a case of a 25 years old woman with progressive hearing loss. MRI with gadolinium enhancement demonstrated an intra vestibular schwannoma. In a follow-up control after 5 years MRI revealed no significant changes in tumor size or signal intensity. 3-D volumetric reconstruction offered complimentary information about this 'quiescent' schwannoma. Considering the tumoral behavior (without growth within five years) and the degree of hearing loss no invasive therapy was performed. (author)

2003-01-01

248

Electrical vestibular stimulation and space motion sickness  

Science.gov (United States)

Electrical vestibular stimulation (EVS) in dynamic balance condition was studied in order to search for a new provocative test of space motion sickness (SMS). SMS is usually attributed to a sensory conflict caused by exposure to microgravity. Vestibular information is conflicting but also unusual and insignificant. EVS is in accordance with this feature because it is not the adequate stimulus of the vestibular receptors. EVS was achieved by means of binaural electrical stimulation. Effects of EVS were potentiated by compelling the subject to maintain dynamic balance on a seesaw. The quantification of this function was performed before, during and after EVS in order to investigate a possible relationship between objective consequences of EVS i.e. dynamic balance disturbances, and the discomfort experienced by the subjects. Dynamic balancing skill was statistically worsened during EVS. Moreover EVS evoked subjective symptoms of SMS in 17 out of the 30 subjects examined. During EVS in eyes open conditions, the subjects who encountered the strongest discomfort, presented the most disturbed dynamic balance, evidencing a relationship between the level of discomfort and the imbalance arising from EVS. This method could thus constitute an interesting basis of SMS ground-based test.

Severac, Alexandra

249

Audiologic and Vestibular Findings in Wolfram Syndrome.  

UK PubMed Central (United Kingdom)

OBJECTIVES:: Assessment of auditory and vestibular function in Wolfram Syndrome (WS) patients, using a standardized protocol. DESIGN:: Prospective cohort study of 11 patients using otoscopic inspection, tympanometry, otoacoustic emissions, pure tones, speech in noise (SIN), the Speech Intelligibility Index, and rotational chair testing. RESULTS:: Mean SNHL diagnosis was 7.3 years with 55% prevalence. Four patients with a Speech Intelligibility Index less than 0.75 (better ear) routinely used bilateral amplification devices. Two patients with normal-hearing sensitivity exhibited abnormal SIN scores. The only patient with significant vestibular dysfunction also had a distinctive low-frequency component to her SNHL. CONCLUSIONS:: Hearing loss may occur earlier than previously suspected, and comprehensive testing including SIN testing may reveal deficits not apparent with pure-tone testing. Particular configurations of hearing loss may indicate a need for comprehensive vestibular assessment. Because SNHL can be the first symptom of WS, audiologists and otolaryngologists should be vigilant about referring patients with hearing loss for ophthalmologic examination.

Karzon RK; Hullar TE

2013-05-01

250

Value of the video head impulse test in assessing vestibular deficits following vestibular neuritis.  

UK PubMed Central (United Kingdom)

To evaluate the performance of the video head impulse test (VHIT) in assessing vestibular deficit in vestibular neuritis. Test validation study was conducted in Tertiary referral center. Twenty-nine patients, referred for vestibular neuritis between October 2009 and March 2012, were included. We recorded age, gender, values of caloric deficit (caloric testing), and deficits in semicircular function (VHIT) at initial presentation and at the follow-up visit (1-3 months). Multivariate linear regression analysis was performed to determine variables associated with values of caloric testing at the follow-up visit. Diagnostic values of VHIT were compared with caloric testing data using the receiver-operating characteristic (ROC) curve and subsequent statistical analysis. At the follow-up visit, complete recovery occurred in 31 % of cases according to caloric evaluation, and VHIT normalized in 51.8 %. Multivariate regression showed that a higher caloric deficit at the follow-up visit was associated with elevated age (p = 0.012) and high caloric deficit at initial presentation (p = 0.042). A lower caloric deficit was associated with normal VHIT results at the follow-up visit (p < 0.001). The ROC curve showed that specificity and sensitivity of VHIT were 100 % when the caloric deficit was respectively lower than 40 % or higher than 62.5 %. At the caloric testing value of 30 %, specificity was 100 %, sensitivity 68.84 %, positive predictive value 100 % and negative predictive value 62.5 %. VHIT is a fast, convenient and specific test to detect vestibular deficits in vestibular neuritis. However, VHIT lacks sensitivity by comparison with caloric testing, especially for moderate vestibular lesions.

Bartolomeo M; Biboulet R; Pierre G; Mondain M; Uziel A; Venail F

2013-03-01

251

Preoperative vestibular ablation with gentamicin and vestibular 'prehab' enhance postoperative recovery after surgery for pontine angle tumours--first report.  

UK PubMed Central (United Kingdom)

CONCLUSIONS: Preoperative gentamicin in combination with vestibular 'prehab' offers a possibility to reduce postoperative malaise and speed up recovery and may be used for patients undergoing such surgery when there is remaining vestibular function. OBJECTIVES: Removal of pontine angle tumours in a patient with remaining vestibular function causes symptoms of acute vestibular loss. A simultaneous cerebellar lesion can cause a combined vestibule-cerebellar lesion. PATIENTS AND METHODS: Twelve patients with pontine angle tumours but with near normal vestibular function were treated with intratympanic gentamicin in combination with vestibular 'prehab' to achieve preoperative vestibular ablation and compensation. After work-up patients started with a home-based vestibular training programme for 14 days. They then received a total of 1.2 ml of 30 mg/ml buffered gentamicin in four intratympanic installations over 2 days. They continued training and returned 6-16 weeks later. All patients were tested with calorics, vestibular video-impulse testing of all six canals, VEMP, subjective visual vertical and horizontal, posturography and pure tone and speech audiometry. RESULTS: There was a loss of caloric reactions and loss of impulses. In two patients the hearing deteriorated and in one hearing improved. All subjects were vestibulary compensated before surgery and no patient complained of dizziness or vertigo after surgery.

Magnusson M; Kahlon B; Karlberg M; Lindberg S; Siesjö P

2007-12-01

252

Reabilitação vestibular: utilidade clínica em pacientes com esclerose múltipla/ Vestibular rehabilitation: clinical benefits to patients with multiple sclerosis  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo desse estudo foi analisar a eficácia do exercício de reabilitação vestibular em dois casos de esclerose múltipla remitente-recorrente. Ambos os casos foram encaminhados do Hospital de Clínicas para o Laboratório de Otoneurologia de uma instituição de ensino e foram submetidos aos seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular e aplicação do Dizziness Handicap Inventory pré e pós reabilitação vestibular utilizando (more) -se o protocolo de Cawthorne e Cooksey. No primeiro caso, gênero feminino, 35 anos, tempo de doença de seis anos, referiu tontura há três anos, de intensidade moderada de ocorrência frequente, cefaléia, quedas, desvio de marcha à direita e sensação de desmaio (sic). Apresentou no exame labiríntico, síndrome vestibular periférica deficitária bilateral. No segundo caso, gênero feminino, 49 anos, tempo de doença de dois anos, referiu desvio de marcha à direita, dificuldade e/ou dor ao movimento do pescoço, formigamento de extremidade e alteração vocal. Apresentou no exame labiríntico, síndrome vestibular periférica deficitária à direita. Houve melhora significativa em ambos os casos dos aspectos físico, funcional e emocional do Dizziness Handicap Inventory após a realização da reabilitação vestibular. O protocolo utilizado promoveu melhora na qualidade de vida e auxiliou no processo de compensação vestibular. Abstract in english The aim of the present study was to analyze the effectiveness of vestibular rehabilitation exercises in two cases of remittent-recurrent multiple sclerosis. Both cases were referred from the Clinics Hospital to the Laboratory of Otoneurology of the same institution and were submitted to the following procedures: anamnesis, otological inspection, vestibular evaluation, and application of the Dizziness Handicap Inventory before and after vestibular rehabilitation using the (more) Cawthorne and Cooksey protocol. The first case was a 35-year-old female, diagnosed for six years, who referred frequent dizziness of moderate intensity for three years, headaches, falls, deviation of gait to the right and fainting sensations (sic). In the vestibular exam, she presented bilateral peripheral vestibular deficiency syndrome. The second case was a 49-year-old female, diagnosed for two years, who referred deviation of gait to the right, difficulty and/or pain with neck movement, paraesthesia of the extremities and vocal alteration. In the vestibular exam, she presented peripheral vestibular deficiency syndrome to the right. Both cases had significant improvements regarding physical, functional and emotional aspects of the Dizziness Handicap Inventory after vestibular rehabilitation. The protocol used benefitted the subjects' quality of life and favored the process of vestibular compensation.

Zeigelboim, Bianca Simone; Klagenberg, Karlin Fabianne; Liberalesso, Paulo Breno Noronha

2010-01-01

253

Reabilitação vestibular: utilidade clínica em pacientes com esclerose múltipla Vestibular rehabilitation: clinical benefits to patients with multiple sclerosis  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo desse estudo foi analisar a eficácia do exercício de reabilitação vestibular em dois casos de esclerose múltipla remitente-recorrente. Ambos os casos foram encaminhados do Hospital de Clínicas para o Laboratório de Otoneurologia de uma instituição de ensino e foram submetidos aos seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular e aplicação do Dizziness Handicap Inventory pré e pós reabilitação vestibular utilizando-se o protocolo de Cawthorne e Cooksey. No primeiro caso, gênero feminino, 35 anos, tempo de doença de seis anos, referiu tontura há três anos, de intensidade moderada de ocorrência frequente, cefaléia, quedas, desvio de marcha à direita e sensação de desmaio (sic). Apresentou no exame labiríntico, síndrome vestibular periférica deficitária bilateral. No segundo caso, gênero feminino, 49 anos, tempo de doença de dois anos, referiu desvio de marcha à direita, dificuldade e/ou dor ao movimento do pescoço, formigamento de extremidade e alteração vocal. Apresentou no exame labiríntico, síndrome vestibular periférica deficitária à direita. Houve melhora significativa em ambos os casos dos aspectos físico, funcional e emocional do Dizziness Handicap Inventory após a realização da reabilitação vestibular. O protocolo utilizado promoveu melhora na qualidade de vida e auxiliou no processo de compensação vestibular.The aim of the present study was to analyze the effectiveness of vestibular rehabilitation exercises in two cases of remittent-recurrent multiple sclerosis. Both cases were referred from the Clinics Hospital to the Laboratory of Otoneurology of the same institution and were submitted to the following procedures: anamnesis, otological inspection, vestibular evaluation, and application of the Dizziness Handicap Inventory before and after vestibular rehabilitation using the Cawthorne and Cooksey protocol. The first case was a 35-year-old female, diagnosed for six years, who referred frequent dizziness of moderate intensity for three years, headaches, falls, deviation of gait to the right and fainting sensations (sic). In the vestibular exam, she presented bilateral peripheral vestibular deficiency syndrome. The second case was a 49-year-old female, diagnosed for two years, who referred deviation of gait to the right, difficulty and/or pain with neck movement, paraesthesia of the extremities and vocal alteration. In the vestibular exam, she presented peripheral vestibular deficiency syndrome to the right. Both cases had significant improvements regarding physical, functional and emotional aspects of the Dizziness Handicap Inventory after vestibular rehabilitation. The protocol used benefitted the subjects' quality of life and favored the process of vestibular compensation.

Bianca Simone Zeigelboim; Karlin Fabianne Klagenberg; Paulo Breno Noronha Liberalesso

2010-01-01

254

Queixas auditivas e vestibulares durante a gestação/ Hearing and vestibular complaints during pregnancy  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese As disfunções hormonais presentes na mulher durante a gravidez podem causar desordens vestibulares e/ou cocleares. OBJETIVO: Verificar a ocorrência de queixas auditivas e vestibulares em gestantes. MATERIAL E MÉTODO: Este é um estudo prospectivo no qual participaram 82 gestantes. Para pesquisa das queixas auditivas e vestibulares foi aplicado às gestantes o Protocolo de Anamnese proposto por Castagno (1994). RESULTADOS: Pode-se observar que o zumbido foi a queixa au (more) ditiva mais citada (33%), sem diferença entre os trimestres gestacionais. A queixa de tontura esteve presente em 52,44% das gestantes e principalmente no primeiro trimestre gestacional. Quanto aos sintomas relacionados à tontura, no primeiro trimestre o mais frequente foi a vertigem, já no segundo trimestre gestacional foi a instabilidade e o desequilíbrio ao caminhar e no terceiro trimestre gestacional foi a instabilidade seguida da tendência a cair. A náusea é o principal sintoma associado à tontura nas gestantes, sendo mais frequente no primeiro trimestre gestacional. CONCLUSÃO: Mulheres durante a gestação referem queixas auditivas e vestibulares, principalmente tontura e zumbido. Abstract in english Hormonal dysfunctions in women during pregnancy can cause vestibular and/or cochlear disorders. AIM: to study hearing and vestibular complaints in pregnant women. MATERIAL AND METHOD: this is a prospective study. 82 pregnant women participated on this study. For hearing and vestibular complaints, a questionnaire proposed by Castagno (1994) was employed. RESULTS: we could observe that tinnitus was the main auditory complaint (33%), although with no differences between the (more) groups. Tinnitus was present among 52.44% of the pregnant women, mainly in the Group 2. According to symptoms related to dizziness, vertigo was the main auditory complaint in first trimester, whereas instability and gait unbalance were more frequent in the second trimester, and instability and tendency to fall in the third trimester. Nausea was the main symptom associated with dizziness in pregnant women, being more frequent in the first trimester of gestation. CONCLUSIONS: women during gestation have auditory and vestibular complaints, mainly dizziness and tinnitus.

Schmidt, Paula Michele da Silva; Flores, Franciele da Trindade; Rossi, Angela Garcia; Silveira, Aron Ferreira da

2010-02-01

255

'PREHAB': Vestibular prehabilitation to ameliorate the effect of a sudden vestibular loss.  

UK PubMed Central (United Kingdom)

A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion found during surgery of the posterior cranial fossa, there may be a risk of a combined vestibulo-cerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well everyday activities may go without any prominent symptoms. We therefore implemented a pre treatment plan before planned vestibular lesions (prehab). This was first done in subject undergoing gentamicin treatment for Meniere's disease (MD). Subjects perform vestibular exercises for 14 days before the first gentamicin installation and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. We then expanded the approach to patients with brainstem tumours requiring surgery but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebello-vestibular lesions. This patient group was given gentamicin installations trans-tympanically before tumour sugary and then underwent prehab. In all cases there was a caloric loss, loss of VOR evident in the head impulse tests, impaired subjective vertical and horizontal, and reduced caloric function induced by the pre-surgery gentamicin treatment. The prehab eliminated spontaneous and positional nystagmus, subjective symptoms, and postural function up before surgery and allowed for rapid postoperative recovery.The concept of 'pre-lesion rehabilitation' where training is introduced before a planned lesion and if possible paralleled with a gradual function loss expands the potential of rehabilitation. Here it was used for vestibular lesions but it is possible that similar approaches may be developed for other situations, which include foreseeable loss of function.

Magnusson M; Karlberg M; Tjernström F

2011-01-01

256

'PREHAB': Vestibular prehabilitation to ameliorate the effect of a sudden vestibular loss.  

Science.gov (United States)

A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion found during surgery of the posterior cranial fossa, there may be a risk of a combined vestibulo-cerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well everyday activities may go without any prominent symptoms. We therefore implemented a pre treatment plan before planned vestibular lesions (prehab). This was first done in subject undergoing gentamicin treatment for Meniere's disease (MD). Subjects perform vestibular exercises for 14 days before the first gentamicin installation and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. We then expanded the approach to patients with brainstem tumours requiring surgery but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebello-vestibular lesions. This patient group was given gentamicin installations trans-tympanically before tumour sugary and then underwent prehab. In all cases there was a caloric loss, loss of VOR evident in the head impulse tests, impaired subjective vertical and horizontal, and reduced caloric function induced by the pre-surgery gentamicin treatment. The prehab eliminated spontaneous and positional nystagmus, subjective symptoms, and postural function up before surgery and allowed for rapid postoperative recovery.The concept of 'pre-lesion rehabilitation' where training is introduced before a planned lesion and if possible paralleled with a gradual function loss expands the potential of rehabilitation. Here it was used for vestibular lesions but it is possible that similar approaches may be developed for other situations, which include foreseeable loss of function. PMID:22027076

Magnusson, Måns; Karlberg, Mikael; Tjernström, Fredrik

2011-01-01

257

Reabilitação vestibular em um hospital universitário/ Vestibular rehabilitation in a university hospital  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A Reabilitação Vestibular visa melhorar o equilíbrio global, a qualidade de vida e orientação espacial dos pacientes com tontura. OBJETIVOS: Traçar o perfil dos pacientes atendidos no Ambulatório de Reabilitação Vestibular do Setor de Otoneurologia de um hospital universitário e verificar os resultados obtidos no período de novembro/2000 a dezembro/2004. MATERIAL E MÉTODO: Levantamento de dados contidos nas fichas dos 93 pacientes submetidos à Reabilitação (more) Vestibular no período. FORMA DE ESTUDO: Clínico retrospectivo. RESULTADOS: A média etária dos pacientes foi de 52,82 anos, 56 do sexo feminino e 37 do sexo masculino. O número médio de atendimentos foi 4,3, sendo maior para os pacientes com distúrbios otoneurológicos centrais (média de 5,9). Dentre os pacientes que concluíram o tratamento proposto, 37 (60,7%) obtiveram melhora significativa, 14 (22,9%) tiveram melhora parcial e 10 (16,4%) não referiram benefícios significativos. Os pacientes que mais se beneficiaram com a Reabilitação Vestibular tinham distúrbios otoneurológicos periféricos. CONCLUSÃO: A maior parte dos pacientes era do sexo feminino, com idade média de 52,8 anos. Cinqüenta e um pacientes (83,6%) tiveram benefício com a terapia confirmando a eficácia do tratamento. Abstract in english The aim of vestibular rehabilitation is to improve total balance, quality of life and spatial orientation of patients with dizziness. AIMS: To determine the characteristics of the patients who underwent the Vestibular Rehabilitation program of the Neurotology Ward of a University Hospital, and to verify the results obtained between November/2000 and December/2004. MATERIALS AND METHODS: analysis of 93 files from patients under Vestibular Rehabilitation during the studied (more) period. STUDY DESIGN: Retrospective clinical. RESULTS: the mean age of patients was 52.82 years, 56 females and 37 males. The average number of therapy sessions was 4.3, higher for patients with central neurotological disorders (average of 5.9). Among the patients who concluded the treatment, 37 (60.7%) had significant improvement, 14 (22.9%) presented partial improvement and 10 (16.4%) did not report significant benefits. Patients with peripheral neurotological disorders were the ones who most benefited from Vestibular Rehabilitation. CONCLUSION: Most of the patients were female, with a mean age of 52.8 years. Fifty one patients (83.6%) benefited from the therapy, confirming treatment efficacy.

Tavares, Flávia da Silva; Santos, Maria Francisca Colella dos; Knobel, Keila Alessandra Baraldi

2008-04-01

258

Reabilitação vestibular em um hospital universitário Vestibular rehabilitation in a university hospital  

Directory of Open Access Journals (Sweden)

Full Text Available A Reabilitação Vestibular visa melhorar o equilíbrio global, a qualidade de vida e orientação espacial dos pacientes com tontura. OBJETIVOS: Traçar o perfil dos pacientes atendidos no Ambulatório de Reabilitação Vestibular do Setor de Otoneurologia de um hospital universitário e verificar os resultados obtidos no período de novembro/2000 a dezembro/2004. MATERIAL E MÉTODO: Levantamento de dados contidos nas fichas dos 93 pacientes submetidos à Reabilitação Vestibular no período. FORMA DE ESTUDO: Clínico retrospectivo. RESULTADOS: A média etária dos pacientes foi de 52,82 anos, 56 do sexo feminino e 37 do sexo masculino. O número médio de atendimentos foi 4,3, sendo maior para os pacientes com distúrbios otoneurológicos centrais (média de 5,9). Dentre os pacientes que concluíram o tratamento proposto, 37 (60,7%) obtiveram melhora significativa, 14 (22,9%) tiveram melhora parcial e 10 (16,4%) não referiram benefícios significativos. Os pacientes que mais se beneficiaram com a Reabilitação Vestibular tinham distúrbios otoneurológicos periféricos. CONCLUSÃO: A maior parte dos pacientes era do sexo feminino, com idade média de 52,8 anos. Cinqüenta e um pacientes (83,6%) tiveram benefício com a terapia confirmando a eficácia do tratamento.The aim of vestibular rehabilitation is to improve total balance, quality of life and spatial orientation of patients with dizziness. AIMS: To determine the characteristics of the patients who underwent the Vestibular Rehabilitation program of the Neurotology Ward of a University Hospital, and to verify the results obtained between November/2000 and December/2004. MATERIALS AND METHODS: analysis of 93 files from patients under Vestibular Rehabilitation during the studied period. STUDY DESIGN: Retrospective clinical. RESULTS: the mean age of patients was 52.82 years, 56 females and 37 males. The average number of therapy sessions was 4.3, higher for patients with central neurotological disorders (average of 5.9). Among the patients who concluded the treatment, 37 (60.7%) had significant improvement, 14 (22.9%) presented partial improvement and 10 (16.4%) did not report significant benefits. Patients with peripheral neurotological disorders were the ones who most benefited from Vestibular Rehabilitation. CONCLUSION: Most of the patients were female, with a mean age of 52.8 years. Fifty one patients (83.6%) benefited from the therapy, confirming treatment efficacy.

Flávia da Silva Tavares; Maria Francisca Colella dos Santos; Keila Alessandra Baraldi Knobel

2008-01-01

259

Enxaqueca associada a disfunção auditivo-vestibular/ Migraine associated with auditory-vestibular dysfunction  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A associação de distúrbios da audição e equilíbrio com enxaqueca é reconhecida desde a Grécia antiga quando Aretaeus da Capadócia em 131 a.C., fez uma descrição precisa e com detalhes desta ocorrência durante uma crise de enxaqueca. Uma revisão ampla das manifestações otoneurológicas da enxaqueca é apresentada, usando as mais recentes publicações com respeito à epidemiologia, apresentação clínica, fisiopatologia, métodos diagnósticos e manejo dest (more) a síndrome. OBJETIVO: Descrever a entidade clínica "Enxaqueca associada a Disfunção Auditivo-vestibular" no intuito de ajudar médicos otorrinolaringologistas e neurologistas no diagnóstico e no manejo clínico dessa doença. COMENTÁRIOS FINAIS: Uma forte associação existe entre sintomas otoneurológicos e enxaqueca, sendo a enxaqueca associada a disfunção auditivo-vestibular a causa mais comum de vertigem episódica espontânea (não-posicional). Os sintomas podem variar bastante entre pacientes tornando um desafio diagnóstico para o otorrinolaringologista. Esta entidade geralmente se apresenta com ataques de vertigem espontâneos ou posicionais, durando de segundos a dias com sintomas de enxaqueca associados. Uma melhor elucidação da ligação entre os mecanismos vestibulares centrais e os mecanismos da enxaqueca em si, além da descoberta de defeitos em canais iônicos em algumas causas de enxaqueca, ataxia e vertigem, podem levar a um entendimento maior da fisiopatologia da enxaqueca associada a disfunção auditivo-vestibular. Abstract in english The association between hearing and balance disorders with migraine is known since the times of the ancient Greeks, when Aretaeus from Cappadocia in 131 B.C, made an accurate and detailed description of this occurrence during a migraine episode. We present a broad review of migraine neurotological manifestations, using the most recent publications associated with epidemiology, clinical presentation, pathophysiology, diagnostic methods and treatment for this syndrome. AIM: (more) to describe the clinical entity: "Migraine associated with auditory-vestibular dysfunction" in order to help otorhinolaryngologists and neurologists in the diagnosis and management of such disorder. FINAL REMARKS: There is a strong association between neurotological symptoms and migraine, and the auditory-vestibular dysfunction-associated migraine is the most common cause of spontaneous episodic vertigo (non-positional). Symptoms may vary broadly among patients, making it a diagnostic challenge to the otorhinolaryngologist. This entity usually presents with positional or spontaneous vertigo spells, lasting for seconds or days, associated with migraine symptoms. A better understanding of the relationship between central vestibular mechanisms and migraine mechanisms, besides the discovery of ionic channel disorders in some cases of migraine, ataxia and vertigo, may lead to a better understanding of migraine pathophysiology associated with audio-vestibular disorder.

Cal, Renato; Bahmad Jr, Fayez

2008-08-01

260

Enxaqueca associada a disfunção auditivo-vestibular Migraine associated with auditory-vestibular dysfunction  

Directory of Open Access Journals (Sweden)

Full Text Available A associação de distúrbios da audição e equilíbrio com enxaqueca é reconhecida desde a Grécia antiga quando Aretaeus da Capadócia em 131 a.C., fez uma descrição precisa e com detalhes desta ocorrência durante uma crise de enxaqueca. Uma revisão ampla das manifestações otoneurológicas da enxaqueca é apresentada, usando as mais recentes publicações com respeito à epidemiologia, apresentação clínica, fisiopatologia, métodos diagnósticos e manejo desta síndrome. OBJETIVO: Descrever a entidade clínica "Enxaqueca associada a Disfunção Auditivo-vestibular" no intuito de ajudar médicos otorrinolaringologistas e neurologistas no diagnóstico e no manejo clínico dessa doença. COMENTÁRIOS FINAIS: Uma forte associação existe entre sintomas otoneurológicos e enxaqueca, sendo a enxaqueca associada a disfunção auditivo-vestibular a causa mais comum de vertigem episódica espontânea (não-posicional). Os sintomas podem variar bastante entre pacientes tornando um desafio diagnóstico para o otorrinolaringologista. Esta entidade geralmente se apresenta com ataques de vertigem espontâneos ou posicionais, durando de segundos a dias com sintomas de enxaqueca associados. Uma melhor elucidação da ligação entre os mecanismos vestibulares centrais e os mecanismos da enxaqueca em si, além da descoberta de defeitos em canais iônicos em algumas causas de enxaqueca, ataxia e vertigem, podem levar a um entendimento maior da fisiopatologia da enxaqueca associada a disfunção auditivo-vestibular.The association between hearing and balance disorders with migraine is known since the times of the ancient Greeks, when Aretaeus from Cappadocia in 131 B.C, made an accurate and detailed description of this occurrence during a migraine episode. We present a broad review of migraine neurotological manifestations, using the most recent publications associated with epidemiology, clinical presentation, pathophysiology, diagnostic methods and treatment for this syndrome. AIM: to describe the clinical entity: "Migraine associated with auditory-vestibular dysfunction" in order to help otorhinolaryngologists and neurologists in the diagnosis and management of such disorder. FINAL REMARKS: There is a strong association between neurotological symptoms and migraine, and the auditory-vestibular dysfunction-associated migraine is the most common cause of spontaneous episodic vertigo (non-positional). Symptoms may vary broadly among patients, making it a diagnostic challenge to the otorhinolaryngologist. This entity usually presents with positional or spontaneous vertigo spells, lasting for seconds or days, associated with migraine symptoms. A better understanding of the relationship between central vestibular mechanisms and migraine mechanisms, besides the discovery of ionic channel disorders in some cases of migraine, ataxia and vertigo, may lead to a better understanding of migraine pathophysiology associated with audio-vestibular disorder.

Renato Cal; Fayez Bahmad Jr

2008-01-01

 
 
 
 
261

Cerebellar afferent projections from the vestibular nuclei in the cat: an experimental study with the method of retrograde axonal transport of horseradish peroxidase.  

UK PubMed Central (United Kingdom)

Details of cerebellar afferent projections from the vestibular nuclei were investigated by the method of retrograde axonal transport of horseradish peroxidase (HRP) in the cat. The distribution of labeled cells in the vestibular nuclei following HRP injections in various parts of the cerebellum indicates that vestibular neurons in the medial and descending nuclei and cell groups f and x project bilaterally to the entire cerebellar vermis, the flocculus, the fastigal nucleus and the anterior and posterior interpositus nuclei. In addition, labeled cells (giant, medium and small) were consistently found bilaterally in the superior and lateral vestibular nuclei following HRP injections in the nodulus, flocculus, fastigal nucleus, and following large injections in the vermis. No labeled cells were observed in cases of HRP injections in crus I and II, the paramedian lobule, paraflocculus and lateral cerebellar nuclei. The present findings indicate that secondary vestibulocerebellar fibers project to larger areas in the cerebellum and originate from more subdivisions and cell groups of the vestibular nuclear complex than previously known.

Kotchabhakdi N; Walberg F

1978-04-01

262

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

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: Verificar a efetividade dos exercícios de reabilitação vestibular na melhora do zumbido e da tontura por meio de avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) e Tinnitus Handicap Inventory (THI), ambos adaptados à população brasileira. MÉTODOS: Avaliaram-se seis pacientes (dois do sexo masculino e quatro do sexo feminino), na faixa etária de 43 a 70 anos. Os pacientes foram submetidos aos seguintes procedimentos: anamnese, inspeção otológica, avaliação vestibular por meio da vectoeletronistagmografia e aplicação dos questionários pré e pós-reabilitação vestibular, utilizando-se o protocolo de Cawthorne e Cooksey. RESULTADOS: a) com relação às queixas mais referidas, observou-se desequilíbrio à marcha (83,3%), dor de cabeça (66,6%) e depressão (66,6%); b) no exame vestibular todos os pacientes apresentaram alteração na prova calórica, sendo a maior freqüência das síndromes vestibulares periféricas irritativas (83,3%); c) constataram-se no exame vestibular dois casos de síndrome vestibular periférica irritativa, dois casos de síndrome vestibular periférica irritativa unilateral; um caso de síndrome vestibular periférica irritativa bilateral e um caso de síndrome vestibular periférica deficitária unilateral; d) na aplicação do DHI, observou-se melhora nos aspectos: funcional e emocional, mantendo-se inalterado o aspecto físico; e) na aplicação do THI, observou-se melhora em todos os aspectos avaliados. CONCLUSÃO: O protocolo utilizado de reabilitação vestibular promoveu diminuição do zumbido e da tontura, melhorando a qualidade de vida dos pacientes.PURPOSE: To verify the effectiveness of vestibular rehabilitation exercises in the improvement of tinnitus and dizziness through an evaluation carried out before and after the administration of the Dizziness Handicap Inventory (DHI) and the Tinnitus Handicap Inventory (DHI) questionnaires, both adapted to the Brazilian population. METHODS: Six patients (two male and four female), with ages ranging from 43 to 70 years, were evaluated. The patients were submitted to the following procedures: anamnesis, otoscopy, vestibular evaluation through vectoelectronystagmography, and administration of the questionnaires, before and after vestibular rehabilitation, using the Cawthorne and Cooksey protocol. RESULTS: a) regarding the most related complaints, imbalance when walking (83,3%), headache (66,6%) and depression (66,6%), were observed; b) in the vestibular exam all the patients showed alterations in the caloric test, and the most frequent syndrome was the irritative peripheral vestibular (83,3%); c) two cases of irritative peripheral vestibular syndrome, two cases of irritative peripheral unilateral vestibular syndrome, one case of irritative peripheral bilateral vestibular syndrome and one case of peripheral deficient unilateral vestibular syndrome were verified in the vestibular exam; d) in the administration of the DHI, an improvement in the functional and emotional aspects were observed, with the physical aspect remaining unchanged; e) in the administration of the THI, an improvement was observed in all the aspects evaluated. CONCLUSION: The protocol of vestibular rehabilitation used in the study, promoted a decrease in tinnitus and dizziness, hence improving the quality of life of the patients.

Bianca Simone Zeigelboim; Marine Raquel Diniz da Rosa; Karlin Fabianne Klagenberg; Ari Leon Jurkiewicz

2008-01-01

263

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese OBJETIVO: Verificar a efetividade dos exercícios de reabilitação vestibular na melhora do zumbido e da tontura por meio de avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) e Tinnitus Handicap Inventory (THI), ambos adaptados à população brasileira. MÉTODOS: Avaliaram-se seis pacientes (dois do sexo masculino e quatro do sexo feminino), na faixa etária de 43 a 70 anos. Os pacientes foram submetidos aos seguintes procedimentos: (more) anamnese, inspeção otológica, avaliação vestibular por meio da vectoeletronistagmografia e aplicação dos questionários pré e pós-reabilitação vestibular, utilizando-se o protocolo de Cawthorne e Cooksey. RESULTADOS: a) com relação às queixas mais referidas, observou-se desequilíbrio à marcha (83,3%), dor de cabeça (66,6%) e depressão (66,6%); b) no exame vestibular todos os pacientes apresentaram alteração na prova calórica, sendo a maior freqüência das síndromes vestibulares periféricas irritativas (83,3%); c) constataram-se no exame vestibular dois casos de síndrome vestibular periférica irritativa, dois casos de síndrome vestibular periférica irritativa unilateral; um caso de síndrome vestibular periférica irritativa bilateral e um caso de síndrome vestibular periférica deficitária unilateral; d) na aplicação do DHI, observou-se melhora nos aspectos: funcional e emocional, mantendo-se inalterado o aspecto físico; e) na aplicação do THI, observou-se melhora em todos os aspectos avaliados. CONCLUSÃO: O protocolo utilizado de reabilitação vestibular promoveu diminuição do zumbido e da tontura, melhorando a qualidade de vida dos pacientes. Abstract in english PURPOSE: To verify the effectiveness of vestibular rehabilitation exercises in the improvement of tinnitus and dizziness through an evaluation carried out before and after the administration of the Dizziness Handicap Inventory (DHI) and the Tinnitus Handicap Inventory (DHI) questionnaires, both adapted to the Brazilian population. METHODS: Six patients (two male and four female), with ages ranging from 43 to 70 years, were evaluated. The patients were submitted to the fol (more) lowing procedures: anamnesis, otoscopy, vestibular evaluation through vectoelectronystagmography, and administration of the questionnaires, before and after vestibular rehabilitation, using the Cawthorne and Cooksey protocol. RESULTS: a) regarding the most related complaints, imbalance when walking (83,3%), headache (66,6%) and depression (66,6%), were observed; b) in the vestibular exam all the patients showed alterations in the caloric test, and the most frequent syndrome was the irritative peripheral vestibular (83,3%); c) two cases of irritative peripheral vestibular syndrome, two cases of irritative peripheral unilateral vestibular syndrome, one case of irritative peripheral bilateral vestibular syndrome and one case of peripheral deficient unilateral vestibular syndrome were verified in the vestibular exam; d) in the administration of the DHI, an improvement in the functional and emotional aspects were observed, with the physical aspect remaining unchanged; e) in the administration of the THI, an improvement was observed in all the aspects evaluated. CONCLUSION: The protocol of vestibular rehabilitation used in the study, promoted a decrease in tinnitus and dizziness, hence improving the quality of life of the patients.

Zeigelboim, Bianca Simone; Rosa, Marine Raquel Diniz da; Klagenberg, Karlin Fabianne; Jurkiewicz, Ari Leon

2008-01-01

264

Can Electrical Vestibular Noise Be Used for the Treatment of Brain Diseases?  

Science.gov (United States)

The therapy currently available for the treatment of degenerative neurological diseases is far from satisfactory, and a novel therapeutic strategy, especially for pharmacologically unresponsive patients, would be welcomed. The vestibular nerves are known to influence neuronal circuits in the medullary cardiovascular areas and, through the cerebellar vermis, the basal ganglia and the limbic system. By means of noisy galvanic vestibular stimulation (GVS), it may now be possible to ameliorate blunted responsiveness of degenerated neuronal circuits in the brains of multiple system atrophy (MSA) and/or Parkinson's disease (PD) patients, through a mechanism known as stochastic resonance. We evaluate the effect of 24-hour noisy GVS on long-term heart rate dynamics in seven MSA patients, and on daytime locomotor activity dynamics in twelve patients with either PD or levodopa unresponsive parkinsonism. Short-range heart rate variability and long-range anti-correlation of trunk activity are significantly increased by the noisy GVS compared with sham stimulation, suggestive of improved autonomic and motor responsiveness. The noisy GVS is effective in boosting the neuro-degenerative brains of MSA and/or PD patients, including those unresponsive to standard levodopa therapy.

Yamamoto, Yoshiharu; Soma, Rika; Struzik, Zbigniew R.; Kwak, Shin

2005-11-01

265

How can the cochlear implant interfere with the vestibular function?  

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Full Text Available Introduction: The cochlear implant is a therapeutic option for patients with deep neurosensorial deafness. Some implanted patients evolved with dizziness in the postoperative, which started the interest for the vestibular function. Since then, many studies have reported the association between the cochlear implant and the vestibular dysfunctions.

Abramides, Patricia Arena

2009-01-01

266

Facial myokymia as a presenting symptom of vestibular schwannoma.  

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Full Text Available Facial myokymia is a rare presenting feature of a vestibular schwannoma. We present a 48 year old woman with a large right vestibular schwannoma, who presented with facial myokymia. It is postulated that facial myokymia might be due to a defect in the motor axons of the 7th nerve or due to brain stem compression by the tumor.

Joseph B; Rajshekhar V

2002-01-01

267

Evidence for cognitive vestibular integration impairment in idiopathic scoliosis patients  

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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.

Simoneau Martin; Lamothe Vincent; Hutin Émilie; Mercier Pierre; Teasdale Normand; Blouin Jean

2009-01-01

268

The balance of feelings: vestibular modulation of bodily sensations.  

UK PubMed Central (United Kingdom)

The vestibular system processes information about head movement and orientation. No unimodal vestibular cortex has been identified in the mammalian brain. Rather, vestibular inputs are combined with many other sensory signals in the cortex. This arrangement suggests that vestibular input could influence processing in other sensory modalities. Here we show that vestibular stimulation differentially modulates two submodalities of the somatosensory system, increasing sensitivity to tactile input, and independently reducing sensitivity to nociceptive input. These modulations of touch and pain can clearly be distinguished from supramodal attentional effects of vestibular stimulation, because they are bilateral and operate in different directions. Outside the artificial conditions of laboratory stimulation, the vestibular system codes movements of the head, indicating a new relation between the body and the external world. We suggest the vestibular system participates in a form of sensory signal management, changing the balance between the various sensory systems as the relation between the body and the external environment changes. This sensory rebalancing may be a crucial element in the brain's capacity to reorient towards novel or salient features in the environment.

Ferrè ER; Bottini G; Iannetti GD; Haggard P

2013-03-01

269

Involvement of peripheral vestibular nerve in individuals with auditory neuropathy.  

UK PubMed Central (United Kingdom)

The vestibulocochlear nerve is a sensory nerve that serves the organs of hearing and equilibrium. Neuropathies of the nerve, particularly auditory neuropathy may be caused by primary demyelination or by axonal diseases. In disorders affecting the cochlear nerve, it is probable that the vestibular nerve is involved as well. There are isolated reports of the involvement of the inferior vestibular nerve (using vestibular-evoked myogenic potentials) in individuals with AN. However, there is a dearth of information on the involvement of the superior vestibular nerve and other functions such as optokinetic, saccade and vestibulo-occular reflex. A total of three subjects diagnosed as having auditory neuropathy, underwent an extensive vestibular assessment consisting of clinical tests of stability (Romberg, Fukuda stepping test), administration of dizziness questionnaire developed by Maryland hearing and balance centre, cervical vestibular-evoked myogenic potentials and a standard electronystagmography test battery. In the present study, the entire subject population assessed showed hypofunctional caloric responses and absent VEMPs. Two out of the three subjects were asymptomatic of vestibular dysfunction. On the clinical tests of stability, two subjects showed deviations to the right, while one subject performed normally. Thus, the present study indicates a possible involvement of peripheral vestibular nerve involvement in individuals with auditory neuropathy.

Sinha SK; Barman A; Singh NK; Rajeshwari G; Sharanya R

2013-08-01

270

Electronystagmographic analysis of caloric test parameters in vestibular disorders.  

UK PubMed Central (United Kingdom)

The electronystagmographical analysis of the eye movements provoked by caloric stimulation is an important method in the evaluation and topical diagnostic procedure of several vestibular lesions. The aim of the study was to compare the electronystagmographical results of caloric response in several vestibular disorders. The patients were divided into five groups: right and left unilateral and bilateral peripheral lesions, central vestibular dysfunction, and normal vestibular function. In the normal vestibular system group the average caloric nystagmus SPV in normal vestibular system was 17.4 °/s. In the peripheral lesion groups the average slow phase velocities are decreased in the affected side, as we expected. In the compensated vestibular lesion the average ASPV of caloric nystagmus is also decreased on the unaffected side. This might be caused by the effect of the central adaptive mechanisms. According to our observations, in central dysfunctions the average caloric ASPV and the spontaneous nystagmus ASPV is increased (25.0 °/s). This suggests that in central vestibular lesions the central inhibiting mechanisms of the caloric response are impaired. Our results show that electronystagmographical analysis of spontaneous and caloric nystagmus is very important in the evaluation of dizzy patients.

Szirmai A; Keller B

2013-01-01

271

Evaluation and treatment of vestibular dysfunction in children.  

UK PubMed Central (United Kingdom)

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

Rine RM; Wiener-Vacher S

2013-01-01

272

Dynamic tilt thresholds are reduced in vestibular migraine.  

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Vestibular symptoms caused by migraine, referred to as vestibular migraine, are a frequently diagnosed but poorly understood entity. Based on recent evidence that normal subjects generate vestibular-mediated percepts of head motion and reflexive eye movements using different mechanisms, we hypothesized that percepts of head motion may be abnormal in vestibular migraine. We therefore measured motion detection thresholds in patients with vestibular migraine, migraine patients with no history of vestibular symptoms, and normal subjects using the following paradigms: roll rotation while supine (dynamically activating the semicircular canals); quasi-static roll tilt (statically activating the otolith organs); and dynamic roll tilt (dynamically activating the canals and otoliths). Thresholds were determined while patients were asymptomatic using a staircase paradigm, whereby the peak acceleration of the motion was decreased or increased based on correct or incorrect reports of movement direction. We found a dramatic reduction in motion thresholds in vestibular migraine compared to normal and migraine subjects in the dynamic roll tilt paradigm, but normal thresholds in the roll rotation and quasi-static roll tilt paradigms. These results suggest that patients with vestibular migraine may have enhanced perceptual sensitivity (e.g. increased signal-to-noise ratio) for head motions that dynamically modulate canal and otolith inputs together. PMID:22348937

Lewis, Richard F; Priesol, Adrian J; Nicoucar, Keyvan; Lim, Koeun; Merfeld, Daniel M

2011-01-01

273

Rizatriptan reduces vestibular-induced motion sickness in migraineurs  

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A previous pilot study suggested that rizatriptan reduces motion sickness induced by complex vestibular stimulation. In this double-blind, randomized, placebo-controlled study we measured motion sickness in response to a complex vestibular stimulus following pretreatment with either rizatriptan or a...

Furman, Joseph M.; Marcus, Dawn A.; Balaban, Carey D.

274

Normal pressure hydrocephalus after gamma knife radiosurgery for vestibular schwannoma  

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Vestibular schwannomas are not uncommon, and gamma knife radiosurgery is one of the treatment options for symptomatic tumors. Hydrocephalus is a complication of gamma knife treatment of vestibular schwannoma, though the mechanism of the development of hydrocephalus remains controversial. We present ...

Mohammed T; Ahuja M; Ju S; Thomas J

275

Evaluation of vestibular function following cochlear implant surgery  

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Introduction: There are contradictory reports regarding vestibular function after cochlear implant surgery. In this study, we evaluated the influence of cochlear implant surgery on vestibular function by comparing the results of caloric test in both ears of patients who received implants. Materials ...

Masoud Motesaddi Zandi; Maryam Emadi; Mohammad Taghi Khorsandi Ashtiani; Abdorreza Sheibanizadeh; Farzad Moobedshahi

276

Influence of vestibular disease on psychological distress: a multicenter study.  

UK PubMed Central (United Kingdom)

OBJECTIVES: Some patients with dizziness show high comorbidity with psychiatric disorders. However, the association of vestibular deficit with psychological symptoms remains controversial. Thus, we investigated psychological distress (depression and anxiety) in patients with vestibular disease and examined factors modifying the development of psychological distress in these patients, including age, sex, severity of dizziness symptoms, and type of vestibular disease. STUDY DESIGN: Prospective study. SETTING: Tertiary referral center. SUBJECTS AND METHODS: This study enrolled 407 patients with dizziness. Dizziness and the psychological symptoms of all patients were measured using the Korean versions of the Dizziness Handicap Inventory (DHI), the Beck Depression Inventory (BDI), and the Spielberger State-Trait Anxiety Inventory (STAI). We evaluated the influence of vestibular disease type, DHI score, and other factors such as sex and age on the psychological scales (BDI, STAI) through multiple regression analysis. RESULTS: Only DHI score and vestibular neuritis were related significantly to BDI scores in patients with vestibular disease, and only DHI scores were associated with STAI scores. CONCLUSION: Dizziness Handicap Inventory scores and psychological distress were closely associated. Psychological distress might be a consequence of high DHI score rather than of a specific type of vestibular disease, although depressive symptoms were related to vestibular neuritis.

Hong SM; Lee HJ; Lee B; Park SK; Hong SK; Park IS; Kim YB; Kim HJ

2013-05-01

277

 A Novel V- Silicone Vestibular Stent: Preventing Vestibular Stenosis andPreserving Nasal Valves  

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Full Text Available  This report presents a novel style of placing nasal stents. Patientsundergoing surgical procedures in the region of nasal vestibuleand nasal valves are at risk of developing vestibular stenosis andlifelong problems with the external and internal nasal valves;sequels of the repair. The objective of the report is to demonstratea simple and successful method of an inverted V- Stent placementto prevent potential complication of vestibular stenosis and nasalvalve compromise later in life. Following a fall on a sharp edge ofa metallic bed, a sixteen month old child with a deep laceratednasal wound extending from the collumellar base toward thetip of the nose underwent surgical exploration and repair of thenasal vestibule and nasal cavity. A soft silicone stent fashioned asinverted V was placed bilaterally. The child made a remarkablerecovery with no evidence of vestibular stenosis or nasal valveabnormalities. In patients with nasal trauma involving the nasalvestibule and internal and external nasal valves stent placementavoids sequels, adhesions, contractures, synechia vestibularstenosis and fibrosis involving these anatomical structures.The advantages of the described V- stents over the traditionalreadymade ridged nasal stents, tubing’s and composite aural graftsare: a) technical simplicity of use, b) safety, c) less morbidity, d)more comfortable, and e) economical. To our knowledge, this isthe first report of such a stent for prevention of vestibular stenosisand preserving nasal valves.

Wameedh AL-Bassam; Deepa Bhargava; Rashid Al Abri

2012-01-01

278

An electronic prosthesis mimicking the dynamic vestibular function.  

UK PubMed Central (United Kingdom)

This paper presents a functional architecture, system level design, and electronic evaluation of a unilateral vestibular prosthesis. The sensing unit of the prosthesis is a custom-designed one-axis micro-electromechanical system (MEMS) gyroscope. Similar to the natural semicircular canal, the MEMS gyroscope senses angular motion of the head and generates voltages proportional to the corresponding angular acceleration. The voltage is then converted into electric current pulses according to the physiological data relating angular acceleration to the spike count in the vestibular nerve. The current pulses can be delivered to stimulate the corresponding vestibular nerve branch. Electronic properties of the vestibular prosthesis prototype have been systematically evaluated and found to meet the design specifications. A unique feature of the present vestibular implant prototype is the scalability: the sensing unit, pulse generator, and the current source can be potentially implemented on a single chip using integrated MEMS technology.

Shkel AM; Zeng FG

2006-01-01

279

Gait initiation characteristics in elderly patients with unilateral vestibular impairment.  

UK PubMed Central (United Kingdom)

The study tested the hypothesis that vestibular patients (n=14) with chronic unsteadiness caused by a documented peripheral unilateral vestibular dysfunction would display differences in muscular activation and movement pattern during gait initiation compared to age-, gender- and body-size-matched healthy Controls (n=14). The displacements of the whole body Center of Pressure (CoP) during the preparatory phase before the swing leg is lifted, were markedly different in vestibular patients. The backward shift during this phase was significantly smaller than in Controls, coupled with a larger secondary corrective forward shift of the CoP. Conversely, the CoP-shift in the M-L direction towards the stance leg was larger in the vestibular patients. Most vestibular patients lacked the anticipatory tibialis anterior (TA) burst, which normally is a prerequisite for the backward displacement of the CoP that precedes the forward movement. The vestibular patients displayed more pronounced TA-Gastrocnemius coactivation in the stance leg when the swing leg was lifted. The duration of the preparatory phase was significantly longer in vestibular patients than in Controls, with no time differences in the later gait initiation events. The vestibular patients started from a more symmetrical stance and with less M-L variation than the Controls. It is concluded that chronically impaired vestibular function leads to a different strategy to create forward momentum to the body. In addition, there is evidence that vestibular patients have diminished postural stability, or alternatively a more cautious behaviour, when initiating the second step.

Henriksson M; Henriksson J; Bergenius J

2011-04-01

280

Gait initiation characteristics in elderly patients with unilateral vestibular impairment.  

Science.gov (United States)

The study tested the hypothesis that vestibular patients (n=14) with chronic unsteadiness caused by a documented peripheral unilateral vestibular dysfunction would display differences in muscular activation and movement pattern during gait initiation compared to age-, gender- and body-size-matched healthy Controls (n=14). The displacements of the whole body Center of Pressure (CoP) during the preparatory phase before the swing leg is lifted, were markedly different in vestibular patients. The backward shift during this phase was significantly smaller than in Controls, coupled with a larger secondary corrective forward shift of the CoP. Conversely, the CoP-shift in the M-L direction towards the stance leg was larger in the vestibular patients. Most vestibular patients lacked the anticipatory tibialis anterior (TA) burst, which normally is a prerequisite for the backward displacement of the CoP that precedes the forward movement. The vestibular patients displayed more pronounced TA-Gastrocnemius coactivation in the stance leg when the swing leg was lifted. The duration of the preparatory phase was significantly longer in vestibular patients than in Controls, with no time differences in the later gait initiation events. The vestibular patients started from a more symmetrical stance and with less M-L variation than the Controls. It is concluded that chronically impaired vestibular function leads to a different strategy to create forward momentum to the body. In addition, there is evidence that vestibular patients have diminished postural stability, or alternatively a more cautious behaviour, when initiating the second step. PMID:21450469

Henriksson, Marketta; Henriksson, Jan; Bergenius, Johan

2011-03-29

 
 
 
 
281

Paroxismia vestibular: estudo clínico e tratamento de oito pacientes Vestibular paroxysmia: clinical study and treatment of eight patients  

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Full Text Available A paroxismia vestibular é uma síndrome de compressão do VIII nervo craniano e foi denominada inicialmente por Janetta "vertigem posicional incapacitante". Esta síndrome é caracterizada por episódios curtos de vertigem, zumbido, déficit vestibular e auditivo. A RM pode mostrar compressão do VIII nervo por vasos da fossa posterior, como a artéria basilar, artéria vertebral, artéria cerebelar inferior anterior, artéria cerebelar inferior posterior. A paroxismia vestibular pode ser tratada com terapia medicamentosa tais como carbamazepina, fenitoína ou gabapentina, ou com descompressão microvascular do VIII nervo. Este estudo descreve oito pacientes com paroxismia vestibular. Quatro deles mostraram também sinais clínicos sugerindo compressão do V e/ou VII nervos. Sete pacientes tratados com carbamazepina tiveram melhora significativa da vertigem e zumbido.Vestibular paroxysmia is a syndrome of cross-compression of the VIII cranial nerve and was first described by Jannetta who used the term "disabling positional vertigo". This syndrome is characterized by brief attacks of vertigo, tinnitus, vestibular and auditory deficits. MRI may show the VIII nerve compression from vessels in the posterior fossa, such as the basilar, vertebral, anterior-inferior cerebellar or the posterior-inferior cerebellar arteries. Vestibular paroxysmia may be treated either with medical therapy, such as carbamazepine, phenytoin or gabapentin or with the microvascular decompression of the VIII nerve. This study describes eight patients with vestibular paroxysmia. Four of them showed also clinical signs suggesting cross-compression of the V and/or VII nerve. Seven patients treated with carbamazepine had significant improvement of vertigo and tinnitus.

Aline Mizuta Kozoroski Kanashiro; Paula Levatti Alexandre; Cristiana Borges Pereira; Antonio Carlos de Paiva Melo; Milberto Scaff

2005-01-01

282

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

Directory of Open Access Journals (Sweden)

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

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

2006-01-01

283

Virtual Neuron  

Science.gov (United States)

Neurons are able to communicate with each other using biochemicals called neurotransmitters. Use Virtual Neuron to explore neurotransmitter properties, make neurons fire, and manipulate neural circuits.

2009-04-14

284

Vestibular dysfunction in chronic inflammatory demyelinating polyneuropathy.  

Science.gov (United States)

Chronic inflammatory demyelinating polyneuropathy (CIDP) has occasionally been associated with clinical or laboratory evidence (magnetic resonance imaging,[MRI], visual evoked response, and brainstem auditory evoked response [BAER] of cranial neuropathy. In most cases, the relationship of cranial nerve involvement to CIDP remains unclear. A 45-year-old woman noted foot numbness, limb weakness, gait and postural instability, and oscillopsia. An IgG kappa monoclonal gammopathy of undetermined significance was found. Bilateral vestibulopathy was documented by clinical examination, bithermal calorics, rotary chair testing, BAERs, and dynamic posturography. MRI with gadolinium demonstrated enhancement of cranial nerve VIII bilaterally. Over the next 6 years, the patients's relapsing and remitting course of CIDP and vestibulopathy was assessed by quantitative muscle and vestibular function testing (clinically and neurophysiologically), and dynamic visual acuity. There was a striking synchronization between her CIDP and vestibulopathy with respect to clinical course including relapses and responses to immune therapy. The response to therapy, and evidence derived from clinical and laboratory investigations, suggest that the vestibular dysfunction was immune mediated. PMID:8619531

Frohman, E M; Tusa, R; Mark, A S; Cornblath, D R

1996-04-01

285

Vestibular dysfunction in chronic inflammatory demyelinating polyneuropathy.  

UK PubMed Central (United Kingdom)

Chronic inflammatory demyelinating polyneuropathy (CIDP) has occasionally been associated with clinical or laboratory evidence (magnetic resonance imaging,[MRI], visual evoked response, and brainstem auditory evoked response [BAER] of cranial neuropathy. In most cases, the relationship of cranial nerve involvement to CIDP remains unclear. A 45-year-old woman noted foot numbness, limb weakness, gait and postural instability, and oscillopsia. An IgG kappa monoclonal gammopathy of undetermined significance was found. Bilateral vestibulopathy was documented by clinical examination, bithermal calorics, rotary chair testing, BAERs, and dynamic posturography. MRI with gadolinium demonstrated enhancement of cranial nerve VIII bilaterally. Over the next 6 years, the patients's relapsing and remitting course of CIDP and vestibulopathy was assessed by quantitative muscle and vestibular function testing (clinically and neurophysiologically), and dynamic visual acuity. There was a striking synchronization between her CIDP and vestibulopathy with respect to clinical course including relapses and responses to immune therapy. The response to therapy, and evidence derived from clinical and laboratory investigations, suggest that the vestibular dysfunction was immune mediated.

Frohman EM; Tusa R; Mark AS; Cornblath DR

1996-04-01

286

[Vestibular function in cochlear implant candidates].  

UK PubMed Central (United Kingdom)

INTRODUCTION: The main problem of a deaf patient is per se communication process. Some of the patients, who are candidates to cochlear implantation report vertigo or imbalance in some everyday situations. The relation of patients' complaints to vestibular loss was evaluated. The authors used electronystagmography which was realized in diagnostic process to cochlear implantation. The results come from the patients diagnosed in our department in 2006-2007. In accordance to the literature, the true vertigo, was rather rare. MATERIAL AND METHODS: Medical history, caloric tests as electronystagmography results were evaluated retrospectively in 47 patients qualified for cochlear implantation in 2006-2007. RESULTS: In the study group, 25 patients did not complain of vertigo; with symmetrical calorics in 10 subjects (40%). The true vertigo reported 6 subjects; 8 subjects had imbalance and unsteadiness on walking. In the group of 47 subjects 8 of them complainted the both- vertigo and imbalance. In the ENG of this group the results of symmetrical responces were evaluated in 57% cases and vestibular hypofunction in 43% subjects. In the group with vertigo (6), 4 subjects (66%) had diagnosed unilateral hypofunction, 1 (17%) bilateral areflexion, 1 subject (17%) had symmetrical responses. CONCLUSIONS: The necessity of the confrontation ENG results to additional examination in audiological part of diagnostic process to cochlear implantation is underlined.

Niemczyk K; Olejniczak A; Kaczorowska M; Miko?ajewska L; Piercha?a K; Morawski K; Paprocki A

2009-03-01

287

Modelling the vestibular head tilt response.  

UK PubMed Central (United Kingdom)

This paper attempts to verify the existence of potentially diagnostically significant periodic signals thought to exist in recordings of neural activity originating from the vestibular nerve, following a single tilt of the head. It then attempts to find the physiological basis of this signal, in particular focusing on the mechanical response of the vestibular system. Simple mechanical models of the semi circular canals having angular velocities applied to them were looked at. A simple single canal model was simulated using CFX software. Finally, a simple model of all three canals with elastic duct walls and a moving cupula was constructed. Pressure waves within the canals were simulated using water hammer or pressure transient theory. In particular, it was investigated whether pressure waves within the utricle following a square pulse angular velocity applied to the canal(s) may be responsible for quasi-periodic oscillatory signals. The simulations showed that there are no pressure waves resonating within the canals following a square pulse angular velocity applied to the canal(s). The results show that the oscillatory signals are most likely not mechanical in origin. It was concluded that further investigation is required.

Heibert D; Lithgow B

2005-03-01

288

Modelling the vestibular head tilt response.  

Science.gov (United States)

This paper attempts to verify the existence of potentially diagnostically significant periodic signals thought to exist in recordings of neural activity originating from the vestibular nerve, following a single tilt of the head. It then attempts to find the physiological basis of this signal, in particular focusing on the mechanical response of the vestibular system. Simple mechanical models of the semi circular canals having angular velocities applied to them were looked at. A simple single canal model was simulated using CFX software. Finally, a simple model of all three canals with elastic duct walls and a moving cupula was constructed. Pressure waves within the canals were simulated using water hammer or pressure transient theory. In particular, it was investigated whether pressure waves within the utricle following a square pulse angular velocity applied to the canal(s) may be responsible for quasi-periodic oscillatory signals. The simulations showed that there are no pressure waves resonating within the canals following a square pulse angular velocity applied to the canal(s). The results show that the oscillatory signals are most likely not mechanical in origin. It was concluded that further investigation is required. PMID:15920988

Heibert, D; Lithgow, B

2005-03-01

289

Improved results for vestibular schwannoma radiosurgery  

International Nuclear Information System (INIS)

PURPOSE/OBJECTIVE: Treatment techniques in radiosurgery have changed since 1987. We reviewed patients who received radiosurgery for vestibular schwannoma to identify these changes and to investigate any differences in tumor control and complications. MATERIALS and METHODS: One hundred thirty-eight unilateral vestibular schwannoma patients with a minimum follow-up of two years after treatment with gamma knife radiosurgery between 1987 and 1992 were analyzed. The early treatment group consisted of 55 patients treated between 1987-1989 (median: tumor volume 3.63 cc, Dmin 18.1 Gy, Dmax 35.4 Gy, isocenters 2.3, follow-up 50.4 mos.). The later treatment group consisted of 83 patients treated between 1990-1992 (median: tumor volume 3.81 cc, Dmin 16.0 Gy, Dmax 31.6 Gy, isocenters 4.7, follow-up 35.8 mos.) RESULTS: Clinical tumor recurrence requiring surgical intervention occurred in one patient in each group. The overall actuarial clinical tumor control rate was 98%. Slight increases in tumor size (1 to 2 mm) were identified in five other patients not requiring intervention, because of no further tumor growth (n=4) or shrinkage (n=1). This led to an overall radiologic tumor control rate of 92% (not significantly different in either group). Compared to the early treatment group, the incidence of facial neuropathy (temporary or permanent) decreased in the later group (49% vs. 11%, p

290

Avaliação vestibular no tremor essencial/ Vestibular evaluation in the essential tremor  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese TEMA: o tremor essencial é familial em cerca de 50% dos casos, com uma herança autossômica, possui início insidioso e é lentamente progressivo. PROCEDIMENTOS: avaliou-se no Setor de Otoneurologia de um Hospital Particular em fevereiro de 2007, uma paciente do sexo feminino, branca, 59 anos, casada, artista plástica, com história de tremor na cabeça desde os dois anos de idade (sic). A paciente relata queixa de tontura há vários meses de origem súbita sem acompa (more) nhamento de náusea e/ou queda. Nega perda de força muscular e formigamento em membros superiores e inferiores, rebaixamento da acuidade auditiva e zumbido. A paciente relata que um de seus filhos possuiu tremor nas mãos há dois anos e avós maternos e paternos com Parkinson. Realizaram-se os seguintes procedimentos: anamnese, inspeção otológica e avaliação vestibular por meio da vectoeletronistagmografia. RESULTADOS: observaram-se os seguintes achados ao exame vestibular: nistagmo de posicionamento com características centrais, nistagmo espontâneo presente com os olhos abertos, nistagmo semi-espontâneo do tipo múltiplo e hiper-reflexia em valor absoluto à prova calórica 20ºC (OD e OE). CONCLUSÃO: o exame vestibular mostrou-se sensível e importante para captar alterações em provas que sugerissem envolvimento do sistema nervoso central. Abstract in english BACKGROUND: essential tremors are family-related in about 50% of the cases with an autosomal inheritance and they register an insidious beginning with a slow progression. PROCEDURE: a 59 year old, white female patient, married and whose occupation is a plastic artist with a history of head tremors since she was two years (sic) old was evaluated in the Otoneurology sector of a private hospital, during the period from February 2007. The patient had been complaining of dizzi (more) ness from unknown origin for several months without accompanying nausea and/or falls. She denied any loss of muscular strength or tingling in her upper and lower members and neither any lowering of her auditory sharpness nor buzzing. The patient informed that one of her children suffered hand tremors two years ago and also that both grandparents had Parkinson?s disease. The following procedures were performed: anamnesis, otological inspection and vestibular evaluation through vectoelectronystagmography. RESULTS: the following findings from the vestibular exam were observed: positioning nystagmus with central characteristics, spontaneous nystagmus with the eyes open, semi-spontaneous nystagmus of the multiple and hyperreflexia type in readings absolute to the caloric test at 20ºC (RE and LE). CONCLUSION: the vestibular exam was shown to be sensitive and important for garnering alterations in tests that suggested involvement of the central nervous system.

Zeigelboim, Bianca Simone; Mittelmann, Cláudia

2008-01-01

291

Avaliação vestibular no tremor essencial Vestibular evaluation in the essential tremor  

Directory of Open Access Journals (Sweden)

Full Text Available TEMA: o tremor essencial é familial em cerca de 50% dos casos, com uma herança autossômica, possui início insidioso e é lentamente progressivo. PROCEDIMENTOS: avaliou-se no Setor de Otoneurologia de um Hospital Particular em fevereiro de 2007, uma paciente do sexo feminino, branca, 59 anos, casada, artista plástica, com história de tremor na cabeça desde os dois anos de idade (sic). A paciente relata queixa de tontura há vários meses de origem súbita sem acompanhamento de náusea e/ou queda. Nega perda de força muscular e formigamento em membros superiores e inferiores, rebaixamento da acuidade auditiva e zumbido. A paciente relata que um de seus filhos possuiu tremor nas mãos há dois anos e avós maternos e paternos com Parkinson. Realizaram-se os seguintes procedimentos: anamnese, inspeção otológica e avaliação vestibular por meio da vectoeletronistagmografia. RESULTADOS: observaram-se os seguintes achados ao exame vestibular: nistagmo de posicionamento com características centrais, nistagmo espontâneo presente com os olhos abertos, nistagmo semi-espontâneo do tipo múltiplo e hiper-reflexia em valor absoluto à prova calórica 20ºC (OD e OE). CONCLUSÃO: o exame vestibular mostrou-se sensível e importante para captar alterações em provas que sugerissem envolvimento do sistema nervoso central.BACKGROUND: essential tremors are family-related in about 50% of the cases with an autosomal inheritance and they register an insidious beginning with a slow progression. PROCEDURE: a 59 year old, white female patient, married and whose occupation is a plastic artist with a history of head tremors since she was two years (sic) old was evaluated in the Otoneurology sector of a private hospital, during the period from February 2007. The patient had been complaining of dizziness from unknown origin for several months without accompanying nausea and/or falls. She denied any loss of muscular strength or tingling in her upper and lower members and neither any lowering of her auditory sharpness nor buzzing. The patient informed that one of her children suffered hand tremors two years ago and also that both grandparents had Parkinson’s disease. The following procedures were performed: anamnesis, otological inspection and vestibular evaluation through vectoelectronystagmography. RESULTS: the following findings from the vestibular exam were observed: positioning nystagmus with central characteristics, spontaneous nystagmus with the eyes open, semi-spontaneous nystagmus of the multiple and hyperreflexia type in readings absolute to the caloric test at 20ºC (RE and LE). CONCLUSION: the vestibular exam was shown to be sensitive and important for garnering alterations in tests that suggested involvement of the central nervous system.

Bianca Simone Zeigelboim; Cláudia Mittelmann

2008-01-01

292

Função vestibular no acidente vascular cerebral do território carotídeo/ Vestibular function in carotid territory stroke patients  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Pacientes após Acidente Vascular Cerebral (AVC) podem apresentar sintomas otoneurológicos. OBJETIVO: Avaliar a função vestibular de pacientes com antecedente pessoal de AVC no território carotídeo. Desenho científico: estudo de coorte histórica com corte transversal. MÉTODO: Quarenta pacientes foram submetidos à anamnese, exame otorrinolaringológico, Dizziness Handicap Inventory e vectoeletronistagmografia. RESULTADOS: Anormalidades discretas dos movimentos sac (more) ádicos foram encontradas em 20 pacientes (50,0%); nove referiram desequilíbrio e um tontura. O ganho do rastreio pendular foi anormal em 17 casos (42,5%); seis referiram desequilíbrio e um tontura. Preponderância direcional anormal do nistagmoperrotatório ocorreu em dois casos (5,0%), que referiram desequilíbrio. A prova calórica identificou três casos (7,5%) com predomínio labiríntico anormal e dois (5,0%) com preponderância direcional anormal do nistagmo; os cinco casos relataram desequilíbrio. Dos 11 pacientes que não referiram manifestações de alteração do equilíbrio corporal, 10 apresentaram alterações nos movimentos sacádicos e no rastreio pendular e um apresentou exame vestibular normal. CONCLUSÃO: Pacientes com antecedente pessoal de AVC no território carotídeo podem apresentar tontura ou desequilíbrio corporal e sinais de comprometimento da motilidade ocular e da função vestibular. Abstract in english Stroke patients may present otoneurological symptoms. OBJECTIVE: To assess the vestibular function of subjects with a history of carotid territory stroke. METHOD: This historical cohort cross sectional study enrolled 40 patients; subjects answered the Dizziness Handicap Inventory, were interviewed and submitted to ENT examination and vectorelectronystagmography. RESULTS: Mild saccadic movement anomalies were seen in 20 patients (50.0%); nine complained of imbalance and di (more) zziness. Abnormal smooth pursuit gain was seen in 17 cases (42.5%); six subjects reported imbalance and one complained of dizziness. Abnormal directional preponderance during rotational nystagmus was seen in two cases (5.0%), who also reported imbalance. Three patients (7.5%) and two subjects (5.0%) were found to have abnormal labyrinthine predominance and abnormal nystagmus directional preponderance respectively; all five individuals reported imbalance. Ten of the 11 patients without complaints of disordered balance had altered saccadic and smooth pursuit eye movements, while one had unaltered vestibular function. CONCLUSION: Patients with a history of carotid territory stroke may suffer from dizziness or imbalance and present signs of compromised eye motility and vestibular function.

Pires, Anna Paula Batista de Ávila; Fukujima, Marcia Maiumi; Ganança, Fernando Freitas; Aquino, Letícia de Moraes; Ganança, Maurício Malavasi; Caovilla, Heloisa Helena

2013-02-01

293

Immediate postoperative nystagmus and vestibular symptoms after stapes surgery.  

UK PubMed Central (United Kingdom)

CONCLUSION: Vestibular disturbance is frequent, but mild even immediately after stapes surgery. Vestibular symptoms improved or disappeared quickly, and they did not correlate with nystagmus. Outpatient stapes surgery performed under local anaesthesia is a feasible approach. OBJECTIVE: Vestibular symptoms are common and may prevent outpatient surgery. The time course of vestibular disturbance is unclear, and we aimed to evaluate it immediately after the operation in the recovery room. METHODS: Twenty patients with otosclerosis undergoing stapedotomy were prospectively included in the study. Postoperative symptoms were collected and nystagmus was recorded with video-oculography (VOG) on average 29 min after the surgery. RESULTS: None of the patients had spontaneous nystagmus with gaze fixation. Nine patients (45%) had slow spontaneous horizontal nystagmus (mean slow phase velocity of 1.1°/s) in the primary position without gaze fixation. In seven of these, the nystagmus obeyed Alexander's law. Nine patients (45%) had vestibular symptoms at the end of the surgery, and four patients at the time of VOG recording. Vertigo was experienced immediately after the operation in five, floating sensation in two, and unspecific dizziness in two patients. Vestibular symptoms were mild or moderate in most patients. The occurrence of nystagmus did not correlate with vestibular symptoms (p > 0.05).

Hirvonen TP; Aalto H

2013-08-01

294

Rizatriptan reduces vestibular-induced motion sickness in migraineurs.  

UK PubMed Central (United Kingdom)

A previous pilot study suggested that rizatriptan reduces motion sickness induced by complex vestibular stimulation. In this double-blind, randomized, placebo-controlled study we measured motion sickness in response to a complex vestibular stimulus following pretreatment with either rizatriptan or a placebo. Subjects included 25 migraineurs with or without migraine-related dizziness (23 females) aged 21-45 years (31.0 ± 7.8 years). Motion sickness was induced by off-vertical axis rotation in darkness, which stimulates both the semicircular canals and otolith organs of the vestibular apparatus. Results indicated that of the 15 subjects who experienced vestibular-induced motion sickness when pretreated with placebo, 13 showed a decrease in motion sickness following pretreatment with rizatriptan as compared to pretreatment with placebo (P < 0.02). This significant effect was not seen when subjects were exposed to more provocative vestibular stimulation. We conclude that the serotonin agonist, rizatriptan, reduces vestibular-induced motion sickness by influencing serotonergic vestibular-autonomic projections.

Furman JM; Marcus DA; Balaban CD

2011-02-01

295

Vestibular impairment in patients with Charcot-Marie-tooth disease.  

UK PubMed Central (United Kingdom)

OBJECTIVE: This case-control study aimed to determine whether the imbalance in Charcot-Marie-tooth (CMT) disease is caused only by reduced proprioceptive input or whether the involvement of the vestibular nerve is an additional factor. METHODS: Fifteen patients with CMT disease (aged 48 ± 17 years; 8 women) underwent cervical vestibular-evoked myogenic potentials, which reflect otolith-spinal reflex function, and quantitative horizontal search-coil head-impulse testing, which assesses the high-acceleration vestibulo-ocular reflex of the semicircular canals. RESULTS: Relative to healthy age-matched control subjects, cervical vestibular-evoked myogenic potentials were found to be impaired in 75% of patients (average p13 latency: 23.0 ± 2.7 milliseconds, p = 0.01; average n23 latency: 29.0 ± 1.8 milliseconds, p = 0.01) and the quantitative head-impulse test in 60% of patients (average gain ± 1 SD: 0.67 ± 0.24, p < 0.001). All patients with head-impulse test impairment also showed cervical vestibular-evoked myogenic potential abnormalities, while the reverse was not true. CONCLUSIONS: We conclude that the neuropathic process in patients with CMT disease frequently involves the vestibular nerve and that cervical vestibular-evoked myogenic potentials may be more sensitive than quantitative head-impulse testing for detecting vestibular involvement, in particular at an early disease stage.

Poretti A; Palla A; Tarnutzer AA; Petersen JA; Weber KP; Straumann D; Jung HH

2013-06-01

296

Evaluation of the caffeine effect in the vestibular test.  

UK PubMed Central (United Kingdom)

UNLABELLED: Exists 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 oriented to suspend the ingestion of caffeine 24 to 48 hours before the vestibular test, others did not consider the suspension of this drink necessary. AIM: To evaluate the effect of caffeine in the vestibular test result. STUDY DESIGN: Clinical with transversal cohort. MATERIAL AND METHOD: Sectional and matched research. The vestibular test was performed twice in the same patient, with five days interval between the exams. In the first test, the patient did not drink coffee 24 hours before the exam; in the second, the patient drunk coffee as usual. All of the participants had clinical indication for vestibular test and were used to drinking coffee. RESULTS: Nineteen women, medium age of 49.5 years, participated. The average coffee consumption was three cups per day. The complaints of anxiety and headache were associated with the submission to the vestibular test without coffee. The exams were not statistically different comparing the results of the tests performed with and without the coffee ingestion. CONCLUSION: The moderate ingestion of coffee was not shown to interfere in the results of the vestibular test. Considering that it is recommended that the patient be calm to be submitted to the vestibular test and that the half-life of the caffeine is only six hours, we suggest that the orientation of complete and abrupt drinking coffee suspension of moderate dose before the vestibular test for the individuals used to daily drinking coffee be reevaluated.

Felipe L; Simões LC; Gonçalves DU; Mancini PC

2005-11-01

297

Reabilitação vestibular em idosos com Parkinson/ Vestibular rehabilitation in elderly patients with Parkinson  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese OBJETIVO: verificar a efetividade dos exercícios de reabilitação vestibular (RV) por meio de avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) - adaptação brasileira. MÉTODOS: avaliaram-se oito pacientes (três do sexo feminino e cinco do sexo masculino), na faixa etária de 48 a 71 anos, encaminhados da Associação Paranaense de Parkinson para o Laboratório de Otoneurologia da Universidade Tuiuti do Paraná. Os pacientes fora (more) m divididos em dois grupos e submetidos aos seguintes procedimentos: anamnese, avaliação otorrinolaringológica, avaliação vestibular por meio da vectoeletronistagmografia (VENG) e aplicação do questionário DHI - adaptação brasileira pré e pós RV utilizando-se os protocolos de Cawthorne e Cooksey (grupo A) e Herdman (grupo B). RESULTADOS: a) conforme as queixas otoneurológicas referidas na anamnese, observou-se a prevalência da tontura (100,0%), tremor (100,0%) e desvio de marcha (75,0&); b) no exame vestibular, todos os pacientes (100,0%) apresentaram alteração, sendo a maior freqüência das síndromes vestibulares periféricas deficitárias (62,5%); c) houve melhora significativa dos aspectos funcional (p = 0,020470) e emocional (p = 0,013631) após a realização dos exercícios de RV utilizando-se o protocolo de Cawthorne e Cooksey e do aspecto emocional (p=0,007316) utilizando-se o protocolo de Herdman. CONCLUSÃO: comparando-se os dois protocolos utilizados, verificou-se uma melhora significativa dos pacientes do grupo A, submetidos ao protocolo de Cawthorne e Cooksey (p=0.0231). Abstract in english PURPOSE: to check the effectiveness of vestibular rehabilitation exercises (RV) by means of an evaluation of a pre and post application of the Dizziness Handicap Inventory (DHI) questionnaire (Brazilian version). METHODS: eight patients were evaluated (three female and five male), in the age group varying from 48 to 71, referred from the Paraná Association of Parkinson to the Otoneurological Laboratory of Tuiuti University of Paraná. The patients were divided in two gro (more) ups and submitted to the following procedures: anamnesis, otorhinolaryngological evaluation, vestibular evaluation through vectoelectronystagmography (VENG) and an application of DHI questionnaire (Brazilian version) before and after RV, using Cawthorne and Cooksey (group A) and Herdman (group B) protocols. RESULTS: a) regarding the otoneurological complaints referred to in the anamnesis, the prevalence of dizziness (100.0%), trembling (100.0%) and deviation during walking (75.0%) were observed; b) In the vestibular exam, all patients (100.0%) presented alterations, with the largest incidence being the deficient peripheral vestibular syndromes (62.5%); c) There was significant improvement of the functional (p = 0,020470) and emotional (p = 0,013631) aspects after accomplishing the RV exercises using the Cawthorne and Cooksey protocol and of the emotional aspect (p=0,007316) using Herdman protocol. CONCLUSION: comparing the two protocols used, a significant improvement of group A patients, submitted to the protocol of Cawthorne and Cooksey (p=0.0231), was confirmed.

Martins-Bassetto, Jackeline; Zeigelboim, Bianca Simone; Jurkiewicz, Ari Leon; Ribas, Angela; Rosa, Marine Raquel Diniz da

2007-06-01

298

Reabilitação vestibular em idosos com Parkinson Vestibular rehabilitation in elderly patients with Parkinson  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: verificar a efetividade dos exercícios de reabilitação vestibular (RV) por meio de avaliação pré e pós-aplicação do questionário Dizziness Handicap Inventory (DHI) - adaptação brasileira. MÉTODOS: avaliaram-se oito pacientes (três do sexo feminino e cinco do sexo masculino), na faixa etária de 48 a 71 anos, encaminhados da Associação Paranaense de Parkinson para o Laboratório de Otoneurologia da Universidade Tuiuti do Paraná. Os pacientes foram divididos em dois grupos e submetidos aos seguintes procedimentos: anamnese, avaliação otorrinolaringológica, avaliação vestibular por meio da vectoeletronistagmografia (VENG) e aplicação do questionário DHI - adaptação brasileira pré e pós RV utilizando-se os protocolos de Cawthorne e Cooksey (grupo A) e Herdman (grupo B). RESULTADOS: a) conforme as queixas otoneurológicas referidas na anamnese, observou-se a prevalência da tontura (100,0%), tremor (100,0%) e desvio de marcha (75,0&); b) no exame vestibular, todos os pacientes (100,0%) apresentaram alteração, sendo a maior freqüência das síndromes vestibulares periféricas deficitárias (62,5%); c) houve melhora significativa dos aspectos funcional (p = 0,020470) e emocional (p = 0,013631) após a realização dos exercícios de RV utilizando-se o protocolo de Cawthorne e Cooksey e do aspecto emocional (p=0,007316) utilizando-se o protocolo de Herdman. CONCLUSÃO: comparando-se os dois protocolos utilizados, verificou-se uma melhora significativa dos pacientes do grupo A, submetidos ao protocolo de Cawthorne e Cooksey (p=0.0231).PURPOSE: to check the effectiveness of vestibular rehabilitation exercises (RV) by means of an evaluation of a pre and post application of the Dizziness Handicap Inventory (DHI) questionnaire (Brazilian version). METHODS: eight patients were evaluated (three female and five male), in the age group varying from 48 to 71, referred from the Paraná Association of Parkinson to the Otoneurological Laboratory of Tuiuti University of Paraná. The patients were divided in two groups and submitted to the following procedures: anamnesis, otorhinolaryngological evaluation, vestibular evaluation through vectoelectronystagmography (VENG) and an application of DHI questionnaire (Brazilian version) before and after RV, using Cawthorne and Cooksey (group A) and Herdman (group B) protocols. RESULTS: a) regarding the otoneurological complaints referred to in the anamnesis, the prevalence of dizziness (100.0%), trembling (100.0%) and deviation during walking (75.0%) were observed; b) In the vestibular exam, all patients (100.0%) presented alterations, with the largest incidence being the deficient peripheral vestibular syndromes (62.5%); c) There was significant improvement of the functional (p = 0,020470) and emotional (p = 0,013631) aspects after accomplishing the RV exercises using the Cawthorne and Cooksey protocol and of the emotional aspect (p=0,007316) using Herdman protocol. CONCLUSION: comparing the two protocols used, a significant improvement of group A patients, submitted to the protocol of Cawthorne and Cooksey (p=0.0231), was confirmed.

Jackeline Martins-Bassetto; Bianca Simone Zeigelboim; Ari Leon Jurkiewicz; Angela Ribas; Marine Raquel Diniz da Rosa

2007-01-01

299

Vestibular syndrome in giant anteater (Myrmecophaga tridactyla) / Síndrome vestibular em tamanduá-bandeira (Myrmecophaga tridactyla)  

Directory of Open Access Journals (Sweden)

Full Text Available The vestibular syndrome is a well-defined disease in domestic animals but little known in wild ones. Here this affection of central origin is described in a caquetic adult female giant anteater (Myrmecophaga tridactyla), which presented circling behavior, extensor hypermetry in thoracic limbs, head tilt and spontaneous horizontal and positional vertical nystagmus. The animal received tube feeding twice daily and dexamethasone was given subcutaneous once daily at the dosis of 6mg/kg, with a progressive improvement of health after the second day of treatment. Dose was reduced to a half from fourth to sixth day, and to a quarter on seventh day, when the animal died. On the fifth day, however, circle deambulation had ceased and hypermetry, head tilt and nystagmus were reduced. Treating vestibular syndrome is a challenge in wild animal practice. Treatment is affected by hyporexia and anorexia, making difficult the animals´ health improvement, which generally present muscle atrophy.A síndrome vestibular é uma afecção bem descrita em animais domésticos e pouco relatada em selvagens. Este relato descreveu essa afecção de origem central em uma fêmea adulta de tamanduá-bandeira (Myrmecophaga tridactyla), caquética, apresentando deambulação em círculos, hipermetria extensora nos membros torácicos, desvio da cabeça e nistagmo espontâneo horizontal e posicional vertical. O animal foi alimentado por sonda oral, 2x/dia e instituiu-se tratamento com dexametasona subcutânea na dose 6mg/kg, 1x/dia, com melhora progressiva a partir da segunda administração. A dose foi diminuída pela metade do quarto ao sexto dia, e reduzida novamente à metade no sétimo dia, quando ocorreu óbito. Entretanto, no quinto dia de tratamento, a deambulação em círculos foi interrompida, e a hipermetria, desvio da cabeça e nistagmo diminuídos. O tratamento de animais selvagens com síndrome vestibular é um desafio e é prejudicado pela hiporexia ou anorexia, dificultando a recuperação dos mesmos, que geralmente apresentam diminuição da massa muscular.

Fabrício Singaretti de Oliveira; Paula Fernanda Gubulin Carvalho; Mauro Henrique Bueno de Camargo; Aline Delfini; Leandro Luís Martins

2009-01-01

300

Postural stability in vestibular neuritis: Age, disease duration and residual vestibular function.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To assess the influence of factors that can affect postural instability in vestibular neuritis (VN). STUDY DESIGN: Retrospective data collection study. METHODS: Foam posturography was performed in 58 VN patients. We examined 6 variables: the velocity of movement of the center of pressure (COP) and the envelopment area in eyes closed/foam rubber condition, Romberg's ratios of velocity and area with foam rubber, and the foam ratios of velocity and area with eyes closed. Multiple regression analyses were performed to explore the relationship between these variables and the following independent variables: gender, age, canal paresis (CP) percentage and disease duration. RESULTS: All 6 variables were positively associated with age, CP percentage and a disease duration of 10 days or less (p??0.05). CONCLUSION: VN patients show poor postural performance, which is affected by age, residual vestibular function and disease duration. Once a VN patient passes the acute phase of the vertigo attack, it is likely that age and residual vestibular function make a greater contribution to postural control. LEVEL OF EVIDENCE: 3b Laryngoscope, 2013.

Fujimoto C; Egami N; Kinoshita M; Sugasawa K; Yamasoba T; Iwasaki S

2013-08-01

 
 
 
 
301

Vestibular compensation after vestibular schwannoma surgery: normalization of the subjective visual vertical and disability.  

UK PubMed Central (United Kingdom)

CONCLUSIONS: The degree of caloric weakness before surgery influences faster or slower recovery of patients undergoing vestibular schwannoma surgery. The Dizziness Handicap Inventory (DHI) is a good index to show the recovery of patients as it relates directly to an improvement or not of the subjective visual vertical (SVV). OBJECTIVE: To evaluate the process of recovery of patients as measured by the SVV and the DHI after surgical removal of vestibular schwannoma. METHODS: We studied 24 consecutive patients of the University Hospital of Salamanca who underwent vestibular schwannoma surgery. We assessed age, tumour size, degree of canalicular weakness and preoperative SVV, and their relationship with DHI and SVV at discharge and also at 1, 3 and 6 months postoperatively. RESULTS: Patients with lesser degrees of caloric weakness took longer to normalize SVV than those with a higher caloric weakness before surgery (p < 0.05). There was a significant correlation between DHI and improvements in SVV with time. The differences disappeared in 6 months where all patients, with greater or lesser degree of caloric weakness, had the same results.

Batuecas-Caletrio A; Santacruz-Ruiz S; Muñoz-Herrera A; Sousa P; Otero A; Perez-Fernandez N

2013-05-01

302

Proton beam stereotactic radiosurgery of vestibular schwannomas  

International Nuclear Information System (INIS)

Purpose: The proton beam's Bragg peak permits highly conformal radiation of skull base tumors. This study, prompted by reports of transient (30% each) and permanent (10% each) facial and trigeminal neuropathy after stereotactic radiosurgery of vestibular schwannomas with marginal doses of 16-20 Gy, assessed whether proton beam radiosurgery using a marginal dose of only 12 Gy could control vestibular schwannomas while causing less neuropathy. Methods and Materials: Sixty-eight patients (mean age 67 years) were treated between 1992 and 1998. The mean tumor volume was 2.49 cm3. The dose to the tumor margin (70% isodose line) was 12 Gy. The prospectively specified follow-up consisted of neurologic evaluation and MRI at 6, 12, 24, and 36 months. Results: After a mean clinical follow-up of 44 months and imaging follow-up of 34 months in 64 patients, 35 tumors (54.7%) were smaller and 25 (39.1%) were unchanged (tumor control rate 94%; actuarial control rate 94% at 2 years and 84% at 5 years). Three tumors enlarged: one shrank after repeated radiosurgery, one remained enlarged at the time of unrelated death, and one had not been imaged for 4 years in a patient who remained asymptomatic at last follow-up. Intratumoral hemorrhage into one stable tumor required craniotomy that proved successful. Thus, 97% of tumors required no additional treatment. Three patients (4.7%) underwent shunting for hydrocephalus evident as increased ataxia. Of 6 patients with functional hearing ipsilaterally, 1 improved, 1 was unchanged, and 4 progressively lost hearing. Cranial neuropathies were infrequent: persistent facial hypesthesia (2 new, 1 exacerbated; 4.7%); intermittent facial paresthesias (5 new, 1 exacerbated; 9.4%); persistent facial weakness (2 new, 1 exacerbated; 4.7%) requiring oculoplasty; transient partial facial weakness (5 new, 1 exacerbated; 9.4%), and synkinesis (5 new, 1 exacerbated; 9.4%). Conclusion: Proton beam stereotactic radiosurgery of vestibular schwannomas at the doses used in this study controls tumor growth with relatively few complications.

2002-09-01

303

Vagal and Vestibular Ganglia as Vital Neural-Centers During Development  

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Full Text Available This investigation is an attempt to provide a chronological account of the ontogeny and significance of changing pattern of the neuronal elements in the vagal (nodose) and vestibular ganglia of the chick. Two types of morphologically different neuron-types (dark and light ones) are observed. The dark cells are considered to be active ones, while the light-cells are effete cells, i.e., inactive, dying, dead or degenerating ones which have failed to establish or lost their functional connections. Since the small and medium sized cells are the youngest stages in which the light cells make their first appearance, it is assumed that the establishment of functional connections might begin around the very-small and small cell stage during embryonic development. The appearance of light cells among the very-small ones just on the day of hatching possibly signifies their attempt to eliminate the growing cells since they are no longer needed to replace larger categories of cells which have already well-developed neuronal connections by the day of hatching. In the vagal ganglion is the occurrence of large number of light-cells on E6 from this behavior, it is assumed that the vagus nerve establishes the earliest functional connections (around E6 or even earlier) in view of its vital functions involved in maintaining the life of animal during development because of its connections with vital organs concerned with alimentary, respiratory and cardiac functions. In the vestibular ganglion, the appearance of a few light cells on E6 might indicate the beginning of an early establishment of functional connections in contrast to most other ganglia studied. It is possible that proper maintenance of vestibular function in order to keep the different organs (such as heart, lung, liver, intestine, brain etc) in their most suitable position during early stages of development in relation to the gravitational force, is possibly an important factor for proper development and growth of every organ and system of the body, and to the life of the individual at large.

A. G. Pillay

2001-01-01

304

The expression of calcitonin gene-related Peptide and acetylcholine in the vestibular-related nucleus population of wild-type mice and retinal degeneration fast mice after rotary stimulation.  

UK PubMed Central (United Kingdom)

Due to the lack of an appropriate animal model, few studies have addressed the integration of visual and vestibular information in the visual system. Using a mouse model with a visual defect (retinal degeneration fast, rdf), we have verified that the prepositus hypoglossal nucleus (PrH) and the Kooy cap of the inferior olive medial nucleus (IOK) are key regions in which visual and vestibular information integrate. Although the integration regions were identified, the precise mechanisms of integration require further investigation. The rdf mice and wild-type Kunming mice were randomly assigned to experimental and control subgroups, respectively. Mice in the experimental groups were exposed to rotary motion for 30 min three times at 24-h intervals, whereas mice in the control groups were not exposed to rotary motion. Differences in the number of calcitonin gene-related peptide positive (CGRP-positive) and choline acetyltransferase positive (ChAT-positive) neurons in the vestibular-related nucleus populations of two types of mice were determined. After rotatory stimulus, the number of CGRP-positive and ChAT-positive neurons in the PrH and the IOK was significantly less in rdf mice compared with that in wild-type mice. There were differences in the number of CGRP-positive and ChAT-positive neurons in the other vestibular-related regions, but the differences were not significant, except the difference in the number of ChAT-positive neurons in the medial vestibular nucleus. The expression patterns of CGRP and ChAT were similar to that of Fos in the vestibular-related regions in the two types of mice after rotatory stimulus. The number of CGRP-positive and ChAT-positive neurons and the number of active nerve cells were consistent in those regions in the two types of mice after rotary stimulus. Therefore, we speculated that CGRP and Ach generated and released by neurons in the PrH and the IOK may play roles in the sensory integration of visual and vestibular information in mice.

Xiaocheng W; Zhaohui S; Ka B; Junhui X; Lei Z; Feng X; Guoqing Y; Lining F; Zuoming Z

2013-10-01

305

Distinct spontaneous shrinkage of a sporadic vestibular schwannoma.  

UK PubMed Central (United Kingdom)

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 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 conservatively. Extreme shrinkage of the tumor may occur spontaneously.

Huang X; Caye-Thomasen P; Stangerup SE

2013-04-01

306

Vestibular test findings in individuals with auditory neuropathy: review.  

UK PubMed Central (United Kingdom)

BACKGROUND: The vestibulocochlear nerve is a sensory nerve that serves the organs of hearing and equilibrium. Neuropathies of the nerve, particularly auditory neuropathy, may be caused by primary demyelination or axonal disease. Cochlear amplification function is normal in cases of auditory neuropathy, but afferent neural conduction in the auditory pathway is disordered. It is highly probable that the vestibular nerve has some involvement in disorders affecting the cochlear nerve. OBJECTIVE: To provide an overview of vestibular test findings in individuals with auditory neuropathy. METHOD: A structured literature search was carried out, with no restrictions to the dates searched. CONCLUSION: Auditory neuropathy implicated the vestibular branch of the VIIIth cranial nerve as well as the cochlear nerve. However, there was variability in terms of vestibular test findings.

Sinha SK; Barman A; Singh NK; Rajeshwari G; Sharanya R

2013-05-01

307

Telefones celulares: influência nos sistemas auditivo e vestibular Mobile phones: influence on auditory and vestibular systems  

Directory of Open Access Journals (Sweden)

Full Text Available Os sistemas de telecomunicações emitem radiofreqüência, uma radiação eletromagnética invisível. Telefones celulares transmitem microondas (450900 MHz no sistema analógico e 1,82,2 GHz no sistema digital), muito próximo à orelha do usuário. Esta energia é absorvida pela pele, orelha interna, nervo vestibulococlear e superfície do lobo temporal. OBJETIVO: Revisar a literatura sobre influência dos telefones celulares na audição e equilíbrio. FORMA DE ESTUDO: Revisão sistemática. METODOLOGIA: Foram pesquisados artigos nas bases Lilacs e Medline sobre a influência dos telefones celulares nos sistemas auditivo e vestibular, publicados de 2000 a 2005, e também materiais veiculados na Internet. RESULTADOS: Os estudos sobre radiação do telefone celular e risco de neurinoma do acústico apresentam resultados contraditórios. Alguns autores não encontram maior probabilidade de aparecimento do tumor nos usuários de celulares, enquanto outros relatam que a utilização de telefones analógicos por 10 anos ou mais aumenta o risco para o tumor. A exposição aguda às microondas emitidas pelo celular não influencia a atividade das células ciliadas externas da cóclea, in vivo e in vitro, a condução elétrica no nervo coclear, nem a fisiologia do sistema vestibular em humanos. As próteses auditivas analógicas são mais suscetíveis à interferência eletromagnética dos telefones celulares digitais. CONCLUSÃO: Não há comprovação de lesão cocleovestibular pelos telefones celulares.Telecommunications systems emit radiofrequency, which is an invisible electromagnetic radiation. Mobile phones operate with microwaves (450900 MHz in the analog service, and 1,82,2 GHz in the digital service) very close to the user’s ear. The skin, inner ear, cochlear nerve and the temporal lobe surface absorb the radiofrequency energy. AIM: literature review on the influence of cellular phones on hearing and balance. STUDY DESIGN: systematic review. METHODS: We reviewed papers on the influence of mobile phones on auditory and vestibular systems from Lilacs and Medline databases, published from 2000 to 2005, and also materials available in the Internet. RESULTS: Studies concerning mobile phone radiation and risk of developing an acoustic neuroma have controversial results. Some authors did not see evidences of a higher risk of tumor development in mobile phone users, while others report that usage of analog cellular phones for ten or more years increase the risk of developing the tumor. Acute exposure to mobile phone microwaves do not influence the cochlear outer hair cells function in vivo and in vitro, the cochlear nerve electrical properties nor the vestibular system physiology in humans. Analog hearing aids are more susceptible to the electromagnetic interference caused by digital mobile phones. CONCLUSION: there is no evidence of cochleo-vestibular lesion caused by cellular phones.

Aracy Pereira Silveira Balbani; Jair Cortez Montovani

2008-01-01

308

Telefones celulares: influência nos sistemas auditivo e vestibular/ Mobile phones: influence on auditory and vestibular systems  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Os sistemas de telecomunicações emitem radiofreqüência, uma radiação eletromagnética invisível. Telefones celulares transmitem microondas (450900 MHz no sistema analógico e 1,82,2 GHz no sistema digital), muito próximo à orelha do usuário. Esta energia é absorvida pela pele, orelha interna, nervo vestibulococlear e superfície do lobo temporal. OBJETIVO: Revisar a literatura sobre influência dos telefones celulares na audição e equilíbrio. FORMA DE ESTUDO (more) : Revisão sistemática. METODOLOGIA: Foram pesquisados artigos nas bases Lilacs e Medline sobre a influência dos telefones celulares nos sistemas auditivo e vestibular, publicados de 2000 a 2005, e também materiais veiculados na Internet. RESULTADOS: Os estudos sobre radiação do telefone celular e risco de neurinoma do acústico apresentam resultados contraditórios. Alguns autores não encontram maior probabilidade de aparecimento do tumor nos usuários de celulares, enquanto outros relatam que a utilização de telefones analógicos por 10 anos ou mais aumenta o risco para o tumor. A exposição aguda às microondas emitidas pelo celular não influencia a atividade das células ciliadas externas da cóclea, in vivo e in vitro, a condução elétrica no nervo coclear, nem a fisiologia do sistema vestibular em humanos. As próteses auditivas analógicas são mais suscetíveis à interferência eletromagnética dos telefones celulares digitais. CONCLUSÃO: Não há comprovação de lesão cocleovestibular pelos telefones celulares. Abstract in english Telecommunications systems emit radiofrequency, which is an invisible electromagnetic radiation. Mobile phones operate with microwaves (450900 MHz in the analog service, and 1,82,2 GHz in the digital service) very close to the user?s ear. The skin, inner ear, cochlear nerve and the temporal lobe surface absorb the radiofrequency energy. AIM: literature review on the influence of cellular phones on hearing and balance. STUDY DESIGN: systematic review. METHODS: We reviewed (more) papers on the influence of mobile phones on auditory and vestibular systems from Lilacs and Medline databases, published from 2000 to 2005, and also materials available in the Internet. RESULTS: Studies concerning mobile phone radiation and risk of developing an acoustic neuroma have controversial results. Some authors did not see evidences of a higher risk of tumor development in mobile phone users, while others report that usage of analog cellular phones for ten or more years increase the risk of developing the tumor. Acute exposure to mobile phone microwaves do not influence the cochlear outer hair cells function in vivo and in vitro, the cochlear nerve electrical properties nor the vestibular system physiology in humans. Analog hearing aids are more susceptible to the electromagnetic interference caused by digital mobile phones. CONCLUSION: there is no evidence of cochleo-vestibular lesion caused by cellular phones.

Balbani, Aracy Pereira Silveira; Montovani, Jair Cortez

2008-02-01

309

Avaliação e reabilitação vestibular no indivíduo idoso/ Vestibular assessment and rehabilitation in the elderly  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Considerando a necessidade de propiciar melhora na qualidade de vida do idoso e a elevada incidência de queixas relacionadas aos transtornos de equilíbrio nessa faixa etária, este estudo teve como objetivo avaliar o equilíbrio estático e dinâmico de indivíduos idosos com queixas de tonturas e verificar a eficácia da reabilitação vestibular (RV) individualizada, por meio da comparação do escore do Dizziness Handicap Inventory - DHI (questionário de handicap), (more) antes do início da RV e no momento da alta ou, no máximo, após 12 sessões de reabilitação. Participaram da pesquisa 11 indivíduos de faixa etária acima ou igual a 60 anos, submetidos a diagnóstico otoneurológico, composto de avaliação otorrinolaringológica, audiológica, vectoeletronistagmografia e exames complementares, quando necessário. As principais queixas foram tonturas, desequilíbrio e quedas. Todos os pacientes tiveram diagnóstico de síndrome vestibular periférica, sendo dez irritativos e um deficitário unilateral. Pode-se observar que a maioria dos casos apresentou desaparecimento de seus sintomas ou significativa diminuição em suas manifestações, salvo dois pacientes que apresentavam doenças associadas ou não seguiram as orientações dadas. A RV individualizada mostrou ser um procedimento terapêutico eficaz na terceira idade e o DHI um instrumento importante no acompanhamento da evolução do paciente. Abstract in english Considering the need to improve elderly's quality of life the high incidence of complaints related to equilibrium disturbance in this age group, this study aimed to evaluate the static and dynamic equilibrium of elderly who complain of dizziness and verify the individualized vestibular rehabilitation, comparing dizziness handicap inventory - DHI (handicap questionnaire) score before starting to exercise and at the moment of discharge or after 12 rehabilitation sessions. E (more) leven individuals aged sixty years or more participated in this research, undergoing otoneurologic diagnostic, composed by otorrinilaringologic assessment, audiologic, electron vector tomography an extras exams if needed. The main complaints were dizziness, lack of equilibrium and droppings. All patients were diagnosed with peripheral vestibular syndrome, being ten irritative and one one-sided. It can be noticed that in most cases the symptoms disappeared or decreased. Except for two patients who presented diseases associated or had not followed the orientations. The individualized vestibular rehabilitation has proved to be an effective therapeutic procedure in elderly and DHI an important tool in following patient's evolution.

Mirallas, Natália Daniela Rezende; De Conti, Marta Helena Souza; De Vitta, Alberto; Laurenti, Ruy; Saes, Sandra de Oliveira

2011-01-01

310

Morphological analysis of the vestibular aqueduct by computerized tomography images  

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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{sup 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{sup 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.

Marques, Sergio Ricardo [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil)]. E-mail: sergioanat.morf@epm.br; Smith, Ricardo Luiz [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Isotani, Sadao [Institute of Physics, University of Sao Paulo, Sao Paulo (Brazil); Alonso, Luis Garcia [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Anadao, Carlos Augusto [Otorhinolaryngology Department, Sao Paulo Federal University-Paulista Medical School, Sao Paulo (Brazil); Prates, Jose Carlos [Morphology and Genetics Department, Sao Paulo Federal University-Paulista Medical School, Disciplina de Anatomia Descritiva e Topografica, Rua Botucatu, 740-Edificio Leitao da Cunha, CEP 04023-900, Vila Clementino, Sao Paulo (Brazil); Lederman, Henrique Manoel [Image Diagnosis Department, Sao Paulo Federal University-Paulista Medical School, Sao Paulo (Brazil)

2007-01-15

311

Gait instability caused by vestibular disorders - analysis by tactile sensor.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To elucidate instability of gait performance in patients with vestibular lesions by the use of a tactile sensors placed under both feet. METHODS: Gait analysis was conducted by the use of tactile sensors in 92 patients who had various types of vestibular lesions including vestibular neuritis (VN), acoustic neuroma (AN), and spinocerebellar degeneration (SCD). 26 healthy adults served as a control. Variables were coefficient of variation of stance, swing, and double support durations. Morphological analysis of foot pressure progression during stance was also performed. In addition, differences in each foot's integrated foot pressure in a gait test were measured, especially in cases with unilateral vestibular lesions. All data was comparatively analyzed between each pathological group and control group. A comparative study between intact side foot and lesion side foot was performed in those unilateral vestibular disorder cases as well. RESULTS: Those gait phase related variables were significantly greater in the pathologic group than in the control group, especially under gait with eyes closed. Morphological irregularity of foot pressure progression during stance was shown in cases with VN and SCD and was greatest in SCD cases. As for integrated foot pressure, in most cases with VN, it has become greater in the lesion side foot, suggesting that body center of gravity could shift toward the lesion side during gait. CONCLUSIONS: Gait analysis by the use of tactile sensors could provide additional important information regarding vestibular patho-physiology in patients with vestibular system disorders. Accordingly, gait performance tests should also be taken into consideration as a vestibular function test for patients with vertigo.

Angunsri N; Ishikawa K; Yin M; Omi E; Shibata Y; Saito T; Itasaka Y

2011-08-01

312

Altered phenotype of the vestibular organ in GLAST-1 null mice.  

UK PubMed Central (United Kingdom)

Various studies point to a crucial role of the high-affinity sodium-coupled glutamate aspartate transporter GLAST-1 for modulation of excitatory transmission as shown in the retina and the CNS. While 2-4-month-old GLAST-1 null mice did not show any functional vestibular abnormality, we observed profound circling behavior in older (7 months) animals lacking GLAST-1. An unchanged total number of otoferlin-positive vestibular hair cells (VHCs), similar ribbon numbers in VHCs, and an unchanged VGLUT3 expression in type II VHCs were detected in GLAST-1 null compared to wild-type mice. A partial loss of supporting cells and an apparent decline of a voltage-gated channel potassium subunit (KCNQ4) was observed in postsynaptic calyceal afferents contacting type I VHCs, together with a reduction of neurofilament- (NF200-) and vesicular glutamate transporter 1- (VGLUT1-) positive calyces in GLAST-1 null mice. Taken together, GLAST-1 deletion appeared to preferentially affect the maintenance of a normal postsynaptic/neuronal phenotype, evident only with increasing age.

Schraven SP; Franz C; Rüttiger L; Löwenheim H; Lysakowski A; Stoffel W; Knipper M

2012-06-01

313

[Electron microscopic investigation of connective tissue in vestibular ganglion and nerve in morbus Meniere  

UK PubMed Central (United Kingdom)

Vestibular ganglia of 17 patients with Menière's disease, obtained by transtemporal or translabyrinthine neurectomy, were studied by electron microscopy. Three ganglia removed because of other disease and four ganglia of normal ears taken post mortem served as controls. The neuronal fibrous tissue of Menière cases showed without exception pathologic changes of various extent. The amount of collagen was increased, whereby different fiber diameters were observed as well as changes in the periodicity of cross banding. Signs of continuing collagen formation were found: active fibroblasts and an increased number of isolated Schwann cells without axons, showing deerhorn-like ramifications which enveloped collagen bundles. The blood vessels were frequently surrounded by multiple basal membranes and broad bands of homogenous matrix. The pericytes were either necrotic or nonexistent. The endothelial cell cytoplasma was usually not in an active state. Sometimes it seemed to be autolytic. The pinocytotic activity was strikingly diminished. These qualitative changes of the interstitial tissue might point to a local pathologic event in the region of the vestibular nerve and ganglion.

Gali? M; Helms J

1982-01-01

314

[Diagnosis and treatment of the most frequent vestibular syndromes].  

UK PubMed Central (United Kingdom)

The aims of this study were to identify the most common vestibular syndromes in a dizziness unit, and to observe their clinical aspects and response to treatment. Five hundred and fifteen patients were studied retrospectively in two institutions. Aspects of anamnesis, physical examination and the response to treatment were evaluated. The most frequent syndromes were: benign paroxysmal positioning vertigo (VPPB) (28.5%), phobic postural vertigo (11.5%), central vertigo (10.1%), vestibular neuritis (9.7%), Meniere disease (8.5%), and migraine (6.4%). A good response to treatment was observed in most patients with migraine (78.8%), VPPB (64%), vestibular neuritis (62%), Meniere disease (54.5%) and vestibular paroxismia (54.5%). On the other hand, patients with downbeat nystagmus and bilateral vestibulopathy had poor response (52.6% and 42.8%, respectively). The diagnosis of these most frequent vestibular syndromes were established through anamnesis and physical examination (with specific clinical tests for evaluation of the vestibular function). The correct diagnosis and adequate treatment are important since these syndromes may have a good prognosis.

Kanashiro AM; Pereira CB; Melo AC; Scaff M

2005-03-01

315

[Diagnosis and treatment of the most frequent vestibular syndromes].  

Science.gov (United States)

The aims of this study were to identify the most common vestibular syndromes in a dizziness unit, and to observe their clinical aspects and response to treatment. Five hundred and fifteen patients were studied retrospectively in two institutions. Aspects of anamnesis, physical examination and the response to treatment were evaluated. The most frequent syndromes were: benign paroxysmal positioning vertigo (VPPB) (28.5%), phobic postural vertigo (11.5%), central vertigo (10.1%), vestibular neuritis (9.7%), Meniere disease (8.5%), and migraine (6.4%). A good response to treatment was observed in most patients with migraine (78.8%), VPPB (64%), vestibular neuritis (62%), Meniere disease (54.5%) and vestibular paroxismia (54.5%). On the other hand, patients with downbeat nystagmus and bilateral vestibulopathy had poor response (52.6% and 42.8%, respectively). The diagnosis of these most frequent vestibular syndromes were established through anamnesis and physical examination (with specific clinical tests for evaluation of the vestibular function). The correct diagnosis and adequate treatment are important since these syndromes may have a good prognosis. PMID:15830080

Kanashiro, Aline Mizuta Kozoroski; Pereira, Cristiana Borges; Melo, Antonio Carlos de Paiva; Scaff, Milberto

2005-04-13

316

Malignant transformation of a vestibular schwannoma after gamma knife radiosurgery.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To report a single case of malignant transformation of a vestibular schwannoma after radiosurgery and review the growing body of literature describing patients with malignant transformation of primary benign tumors after radiosurgery, including vestibular schwannoma. METHODS: A 46-year-old woman presented with right facial paresthesias and imaging consistent with a right-sided vestibular schwannoma (volume approximately 18.5 cm(3)). RESULTS: The patient underwent subtotal resection followed by Gamma Knife radiosurgery (GKRS) 6 months after surgery. Initial histology showed a benign vestibular schwannoma with an MIB-1 labeling index of 5.7%. At 43 months after GKRS, the patient underwent repeat subtotal resection of a benign vestibular schwannoma (MIB-1 labeling index 7.4%). At 59 months after GKRS, she underwent a third resection, and histology showed frank malignant transformation (MIB-1 labeling index 33.8%). CONCLUSIONS: Malignant vestibular nerve tumors are extremely rare; only 18 cases have been reported in the literature. Our patient is the sixth pathologically confirmed case of malignant transformation after radiosurgery, supporting the contention that radiosurgery itself may play a causative role in transformation. In a histologically benign lesion, the presence of an elevated MIB-1 labeling index may predispose toward malignant transformation in the setting of adjuvant radiosurgery.

Yanamadala V; Williamson RW; Fusco DJ; Eschbacher J; Weisskopf P; Porter RW

2013-03-01

317

[Vestibular findings in patients with Vogt-Koyanagi-Harada syndrome].  

UK PubMed Central (United Kingdom)

OBJECTIVE: To identify and describe vestibular abnormalities in patients with Vogt-Koyanagi-Harada syndrome (VKH). MATERIALS AND METHOD: Prospective, cross-sectional, observational and descriptive study. Patients with VKH referred by an ophthalmological center, were interrogated and physically examined in search of signs of vestibular abnormalities, and if positive, they underwent videonystagmography, computerized dynamic posturography, tonal audiometry and tympanometry. RESULTS: Out of 21 patients with VKH, only 10 were included in the study due to presenting data of vestibular abnormalities (10/10 with vestibular symptoms and 9/10 with abnormalities in the physical exploration). The age average was 37.8 years. The videonystagmography was mainly abnormal in ocular saccades test (10/10). The posturography showed a higher alteration of the visual (4/10) and vestibular (4/10) afferents. A diagnosis of benign paroxysmal positional vertigo was mostly concluded (6/10). None presented abnormalities of the middle ear nor data of central pathology, 6/10 presented abnormalities in tonal audiometry. CONCLUSIONS: Peripheral vestibular disorder is often present in the population with VKH.

Ruiz-Allec LD; Peñaloza-López YR; Ocaña-Plante Ndel R; Valdivia-Muñoz MB; Martínez-Castro F

2009-09-01

318

Arreflexia pós-calórica bilateral: aplicabilidade clínica da reabilitação vestibular  

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Full Text Available A perda bilateral da função vestibular é rara em pacientes com vertigem e desequilíbrio, porém os sintomas muitas vezes são incapacitantes e seu tratamento é tema controverso na literatura. OBJETIVO: Nosso objetivo foi avaliar e descrever a resposta clínica de pacientes com distúrbio do equilíbrio corporal secundário à arreflexia vestibular pós-calórica bilateral, documentada pela eletronistagmografia, submetidos à Reabilitação Vestibular. FORMA DE ESTUDO: Retrospectivo, inclui um desenho de descrição de casos. MÉTODO: Foram avaliadas as respostas de 8 pacientes portadores de arreflexia pós-calórica bilateral submetidos à Reabilitação Vestibular, observando-se a relação entre os resultados de exame e sintomas pré e pós-tratamento. A avaliação da resposta clínica foi feita por meio de escala analógico-visual. RESULTADOS: Após a Reabilitação Vestibular, 7 (87,5%) dos 8 pacientes submetidos à terapia apresentaram melhora clínica. CONCLUSÃO: embora não seja esperada melhora completa do equilíbrio corporal, a Reabilitação Vestibular é uma terapia eficaz na recuperação desses pacientes.

Bittar Roseli Saraiva Moreira; Bottino Marco Aurélio; Pedalini Maria Elisabete Bovino; Ramalho Jeanne da Rosa Oiticica; Carneiro Camila de Giacomo

2004-01-01

319

Retrosigmoid approach for vestibular neurectomy in Meniere's disease.  

UK PubMed Central (United Kingdom)

BACKGROUND: Vestibular nerve section is considered to be the most effective surgical procedure to control intractable symptoms secondary to Meniere's disease (MD). This study was developed to analyze the adequacy of retrosigmoid vestibular neurectomy in terms of vertigo control, hearing preservation and clinical complications of this procedure. METHODS: A retrospective review was carried out on 14 patients affected by definite unilateral MD who underwent vestibular neurectomy via the retrosigmoid approach. FINDINGS: One patient was lost from follow-up; another one had only a short postoperative observation. At follow-up performed on 12 cases, no patients reported any crisis of acute vertigo. Four patients were free from any vestibular symptoms, while 8 reported some slight gait disturbances. Hearing function was preserved in 10 patients and improved in 2. 1 year postoperative vestibular function was absent at the side operated on and unchanged on the other side in all the cases. CONCLUSIONS: Vestibular neurectomy via the retrosigmoid approach can be considered a safe and effective procedure in relieving medically refractory vertigo in Meniere's disease, while preserving hearing.

Perez R; Ducati A; Garbossa D; Benech F; Fontanella MM; Canale A; Albera R

2005-04-01

320

How the vestibular system interacts with somatosensory perception: A sham-controlled study with galvanic vestibular stimulation.  

Science.gov (United States)

The vestibular system has widespread interactions with other sensory modalities. Here we investigate whether vestibular stimulation modulates somatosensory function, by assessing the ability to detect faint tactile stimuli to the fingertips of the left and right hand with or without galvanic vestibular stimulation (GVS). We found that left anodal and right cathodal GVS, significantly enhanced sensitivity to mild shocks on either hand, without affecting response bias. There was no such effect with either right anodal and left cathodal GVS or sham stimulation. Further, the enhancement of somatosensory sensitivity following GVS does not strongly depend on the duration of GVS, or the interval between GVS and tactile stimulation. Vestibular inputs reach the somatosensory cortex, increasing the sensitivity of perceptual circuitry. PMID:23827220

Ferrè, Elisa R; Day, Brian L; Bottini, Gabriella; Haggard, Patrick

2013-07-01

 
 
 
 
321

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese 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: Estu (more) do 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. Abstract in english 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 the suspension of this drink necessary. AIM: To evaluate the effect of caffeine in the vestibular test result. STUDY DESIGN: clinical with transversal cohort. MATERIAL AND METHOD: Seccional and matched res (more) earch. The vestibular test was performed twice in the same patient, with five days interval between the exams. In the first test, the patient did not drink coffee 24 hours before the exam; in the second, the patient drunk coffee as usual. All of the participants had clinical indication for vestibular test and were used to drinking coffee. RESULTS: Nineteen women, medium age of 49,5 years, participated. The average coffee consumption was three cups per day. The complaints of anxiety and headache were associated with the submission to the vestibular test without coffee. The exams were not statistically different comparing the results of the tests performed with and without the coffee ingestion. CONCLUSION: The moderate ingestion of coffee was not shown to interfere in the results of the vestibular test. Considering that it is recommended that the patient be calm to be submitted to the vestibular test and that the half-life of the caffeine is only of six hours, we suggest that the orientation of complete and abrupt drinking coffee suspension of moderate dose before the vestibular test for the individuals used to daily drinking coffee be reevaluated.

Felipe, Lilian; Simões, Lilia Correia; Gonçalves, Denise Utsch; Mancini, Patrícia Cotta

2005-12-01

322

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

Directory of Open Access Journals (Sweden)

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 the suspension of this drink necessary. AIM: To evaluate the effect of caffeine in the vestibular test result. STUDY DESIGN: clinical with transversal cohort. MATERIAL AND METHOD: Seccional and matched research. The vestibular test was performed twice in the same patient, with five days interval between the exams. In the first test, the patient did not drink coffee 24 hours before the exam; in the second, the patient drunk coffee as usual. All of the participants had clinical indication for vestibular test and were used to drinking coffee. RESULTS: Nineteen women, medium age of 49,5 years, participated. The average coffee consumption was three cups per day. The complaints of anxiety and headache were associated with the submission to the vestibular test without coffee. The exams were not statistically different comparing the results of the tests performed with and without the coffee ingestion. CONCLUSION: The moderate ingestion of coffee was not shown to interfere in the results of the vestibular test. Considering that it is recommended that the patient be calm to be submitted to the vestibular test and that the half-life of the caffeine is only of six hours, we suggest that the orientation of complete and abrupt drinking coffee suspension of moderate dose before the vestibular test for the individuals used to daily drinking coffee be reevaluated.

Lilian Felipe; Lilia Correia Simões; Denise Utsch Gonçalves; Patrícia Cotta Mancini

2005-01-01

323

Síndrome do aqueduto vestibular alargado: uma causa de disacusia neurossensorial The large vestibular aqueduct syndrome: a cause of neurosensory dysacusia  

Directory of Open Access Journals (Sweden)

Full Text Available TEMA: a síndrome do aqueduto vestibular alargado (SAVA) é caracterizada pelo alargamento do aqueduto vestibular associada a disacusia. O grau da perda auditiva é variável, podendo ser flutuante, progressiva ou súbita. Sintomas vestibulares podem estar presentes. O diagnóstico é realizado por exames de imagem. OBJETIVO: relatar um caso de SAVA. MÉTODO: lactente, gênero feminino, realizou tomografia computadorizada de ouvidos e exames de audição. RESULTADO: constatou-se alargamento do aqueduto vestibular maior que 1,5mm de diâmetro e perda auditiva neurossensorial à direita. CONCLUSÃO: com a avaliação auditiva precoce é possível o diagnóstico da disacusia, mesmo em crianças com disacusias unilaterais. Embora a literatura consultada mostre que o diagnóstico da SAVA ocorra tardiamente, no presente caso, o diagnóstico etiológico foi possibilitado pela tomografia computadorizada.BACKGROUND: the large vestibular aqueduct syndrome (LVAS) is characterized by the enlargement of the vestibular aqueduct associated with sensorioneural hearing loss. The level of hearing loss varies and may be fluctuant, progressive or sudden. Vestibular symptoms may be present. The diagnosis is reached by imaging methods. AIM: To report an LVAS case. METHOD: a female infant was submitted to a computerized tomography of the ears and to audiologic tests. RESULTS: enlargement of the vestibular aqueduct of more than 1.5mm and sensorioneural hearing loss in the right ear were observed. CONCLUSION: with an early hearing evaluation it is possible to diagnose hearing loss, even in children were this loss is unilateral. Although the literature indicates that the diagnosis of LVAS occurs at a later age, in this case the etiologic diagnosis was enabled by computerized tomography.

Daniela Polo Camargo da Silva; Jair Cortez Montovani; Danielle Tavares Oliveira; Marisa Portes Fioravanti; Ivanira Ayako Tamashiro

2008-01-01

324

Vestibular rehabilitation: clinical benefits to patients with Parkinson's disease/ Reabilitação vestibular: utilidade clínica em pacientes com doença de Parkinson  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese OBJETIVO: Avaliar a eficácia dos exercícios de reabilitação vestibular (RV) por meio de avaliação pré e pós-aplicação da versão brasileira do questionário Dizziness Handicap Inventory (DHI). MÉTODO: Estudou-se 12 pacientes e realizaram-se os seguintes procedimentos: anamnese, avaliação otorrinolaringológica, vestibular e aplicação do DHI pré e pós RV. RESULTADOS: Do ponto de vista clínico, o tremor de repouso e a instabilidade postural subjetiva foram (more) às queixas motoras mais freqüentes associadas às queixas de vertigem em 12 casos (100%); no exame vestibular, todos os pacientes apresentaram anormalidades, com freqüência das síndromes vestibulares periféricas deficitárias uni e bilaterais em 10 casos (83,3%); houve melhora significativa dos aspectos físico, funcional e emocional do DHI após a realização da RV. CONCLUSÃO: A RV seguindo o protocolo de Cawthorne e Cooksey mostrou-se útil no manejo de queixas subjetivas de diversos aspectos avaliados neste protocolo. Abstract in english OBJECTIVE: To evaluate the effectiveness of the vestibular rehabilitation (VR) exercises by means of an assessment before and after the application of the Brazilian version of the Dizziness Handicap Inventory (DHI) questionnaire. METHOD: Twelve patients were studied, the following procedures were carried out: anamnesis, otorhinolaryngological and vestibular evaluation, and the application of the DHI before and after the VR. RESULTS: Clinically resting tremors and subjecti (more) ve postural instability were the motor complaints most frequently associated with complaints of vertigo in 12 cases (100%); in the vestibular exam, all the patients presented abnormalities, frequently from the uni and bilateral peripheral vestibular deficiency syndromes in 10 cases (83.3%); there was significant improvement in the physical, functional and emotional aspects of the DHI after the completion of the VR. CONCLUSION: The VR following the Cawthorne and Cooksey protocol were shown to be useful in managing subjective complaints of several aspects evaluated in this protocol.

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

2009-06-01

325

Vestibular rehabilitation: clinical benefits to patients with Parkinson's disease Reabilitação vestibular: utilidade clínica em pacientes com doença de Parkinson  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: To evaluate the effectiveness of the vestibular rehabilitation (VR) exercises by means of an assessment before and after the application of the Brazilian version of the Dizziness Handicap Inventory (DHI) questionnaire. METHOD: Twelve patients were studied, the following procedures were carried out: anamnesis, otorhinolaryngological and vestibular evaluation, and the application of the DHI before and after the VR. RESULTS: Clinically resting tremors and subjective postural instability were the motor complaints most frequently associated with complaints of vertigo in 12 cases (100%); in the vestibular exam, all the patients presented abnormalities, frequently from the uni and bilateral peripheral vestibular deficiency syndromes in 10 cases (83.3%); there was significant improvement in the physical, functional and emotional aspects of the DHI after the completion of the VR. CONCLUSION: The VR following the Cawthorne and Cooksey protocol were shown to be useful in managing subjective complaints of several aspects evaluated in this protocol.OBJETIVO: Avaliar a eficácia dos exercícios de reabilitação vestibular (RV) por meio de avaliação pré e pós-aplicação da versão brasileira do questionário Dizziness Handicap Inventory (DHI). MÉTODO: Estudou-se 12 pacientes e realizaram-se os seguintes procedimentos: anamnese, avaliação otorrinolaringológica, vestibular e aplicação do DHI pré e pós RV. RESULTADOS: Do ponto de vista clínico, o tremor de repouso e a instabilidade postural subjetiva foram às queixas motoras mais freqüentes associadas às queixas de vertigem em 12 casos (100%); no exame vestibular, todos os pacientes apresentaram anormalidades, com freqüência das síndromes vestibulares periféricas deficitárias uni e bilaterais em 10 casos (83,3%); houve melhora significativa dos aspectos físico, funcional e emocional do DHI após a realização da RV. CONCLUSÃO: A RV seguindo o protocolo de Cawthorne e Cooksey mostrou-se útil no manejo de queixas subjetivas de diversos aspectos avaliados neste protocolo.

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

2009-01-01

326

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

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese 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 se