Peripheral Vestibular Dysfunction Research Articles

Cerebellar vermis lesions and tumours of the fourth ventricle in patients with positional and positioning vertigo and nystagmus

Positional and positioning vertigo and nystagmus syndromes are usually due to peripheral vestibular dysfunction. The most common form is benign paroxysmal positioning. In this paper, we discuss more serious aetiologies in the differential diagnosis for patients presenting with a history suggestive of benign paroxysmal positioning vertigo. We draw attention to the diagnosis of cerebellar vermis lesions and tumours of the fourth ventricle by presenting two cases of patients with positional nystagmus of so called benign paroxysmal type. We review the literature on positional nystagmus, highlighting key findings on history and physical examination to aid in the correct diagnosis of benign paroxysmal positioning vertigo, and to differentiate it from the rare yet sinister central aetiologies that can present with positional vertigo of the benign positional type. This is with the aim to avoid over-investigating a common presentation without missing a serious diagnosis.

Edaravone protects the vestibular periphery from free radical-induced toxicity in response to perilymphatic application of (±)- α-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid

Intracochlear infusion of (±)- α-amino-3-hydroxy-5-methyl-isoxazole-4-propionic acid (AMPA) was performed with a syringe pump in guinea pigs, and peripheral vestibular dysfunction was induced. Animals were administered edaravone systemically or topically. In the systemic application group, animals were administered edaravone once a day for 7 days after AMPA infusion. In the topical application group, edaravone-soaked gelfoam was placed on the round window membrane just after, 12 h after or 24 h after AMPA infusion. Spontaneous nystagmus was observed after AMPA infusion. Immunohistochemistry for 4-hydroxy-2-nonenal (4-HNE), a marker of free radical-induced lipid peroxidation, was performed 24 h after AMPA infusion. In addition, caloric tests were performed to evaluate vestibular function 1 week after AMPA infusion. Animals in both groups showed decreased spontaneous nystagmus, but results were not significant. Animals treated topically with edaravone within 12 h of AMPA infusion showed normal morphology of the ampullar sensory epithelia of the lateral semicircular canals and showed a good response to the caloric tests. 4-HNE immunoreactivity in the sensory epithelia was very low in these animals. In contrast, untreated animals and animals treated with edaravone systemically or topically 24 h after AMPA infusion showed morphologic hair cell damage, reduced caloric response and remarkable 4-HNE immunoreactivity in the sensory epithelia. These results indicate that topical application of edaravone within 12 h after damage protects the vestibular periphery from free radical-induced toxicity in response to intracochlear infusion of AMPA.

Avaliação oculomotora em pacientes com disfunção vestibular periférica

OBJETIVO: Verificar se os parâmetros dos movimentos sacádicos fixos e randomizados, do rastreio pendular e do nistagmo optocinético na vectonistagmografia digital podem apresentar alterações em pacientes com hipótese diagnóstica de disfunção vestibular periférica. MÉTODO: Foram avaliados 60 pacientes, de ambos os sexos, com tontura de origem vestibular periférica e idade entre 12 e 82 anos. Os achados foram comparados com um padrão de normalidade para os parâmetros dos movimentos oculares estudados. RESULTADOS: Os movimentos sacádicos fixos estavam alterados em 100% dos casos quanto à latência e em 35% quanto à velocidade; os randomizados estavam alterados em 100% quanto à latência, em 78,3% quanto à precisão e 1,7% quanto à velocidade; o rastreio pendular apresentou alteração do ganho nas freqüências de 0,1Hz em 15%, 0,2Hz em 21,7% e 0,4Hz em 13,3%; o nistagmo optocinético apresentou alteração da velocidade angular da componente lenta em 1,7% e do ganho em 5%. CONCLUSÕES: A latência e a velocidade dos movimentos sacádicos fixos; a latência, a precisão e a velocidade dos movimentos randomizados; o ganho do rastreio pendular; a velocidade angular da componente lenta e o ganho do nistagmo optocinético na vectonistagmografia digital podem apresentar alterações em pacientes com hipótese diagnóstica de disfunção vestibular periférica.

Diagnostic Value of Vestibulo-Ocular Reflex Parameters in the Detection and Characterization of Labyrinthine Lesions

To evaluate the power of various parameters of the vestibulo-ocular reflex (VOR) in detecting unilateral peripheral vestibular dysfunction and in characterizing certain inner ear pathologies. Prospective study of consecutive ambulatory patients presenting with acute onset of peripheral vertigo and spontaneous nystagmus. Tertiary referral center. Seventy-four patients (40 females, 34 males) and 22 normal subjects (11 females, 11 males) were included in the study. Patients were classified in three main diagnoses: vestibular neuritis: 40; viral labyrinthitis: 22; Meniere's disease: 12. The VOR function was evaluated by standard caloric and impulse rotary tests (velocity step). A mathematical model of vestibular function was used to characterize the VOR response to rotational stimulation. The diagnostic value of the different VOR parameters was assessed by uni- and multivariable logistic regression. In univariable analysis, caloric asymmetry emerged as the most powerful VOR parameter in identifying unilateral vestibular deficit, with a boundary limit set at 20%. In multivariable analysis, the combination of caloric asymmetry and rotational time constant asymmetry significantly improved the discriminatory power over caloric alone (p<0.0001) and produced a detection score with a correct classification of 92.4%. In discriminating labyrinthine diseases, different combinations of the VOR parameters were obtained for each diagnosis (p<0.003) supporting that the VOR characteristics differ between the three inner ear disorders. However, the clinical usefulness of these characteristics in separating the pathologies was limited. We propose a powerful logistic model combining the indices of caloric and time constant asymmetries to detect a peripheral vestibular loss, with an accuracy of 92.4%. Based on vestibular data only, the discrimination between the different inner ear diseases is statistically possible, which supports different pathophysiologic changes in labyrinthine pathologies.

Oculomotor evaluation in patients with peripheral vestibular dysfunction

SummaryAimTo assess whether or not the parameters of fixed and randomized saccadic movements, of pendular tracking and of optokinetic nystagmus in the digital vectonystagmography may show abnormalities in patients with possible diagnosis of peripheral vestibular dysfunction.Method60 patients with dizziness of peripheral vestibular origin, from 12 to 82 years of age, males and females, were evaluated in the Universidade Federal de São Paulo. Ocular movement parameter findings were compared to a normal pattern.ResultsFixed saccadic movements were altered in 100% of the cases as to latency, and in 35.0% of the cases as to speed; the randomized saccadic movements were altered in 100% of the cases as to latency, in 78.3% as to precision, and in 1.7% as to speed; the pendular tracking showed a gain alteration in the frequencies of 0.1 Hz in 15% of the cases, 0.2 Hz in 21.7%, and 0.4 Hz in 13.3%; the optokinetic nystagmus showed an alteration of the angular speed in the slow component in 1.7% of the cases, and in gain in 5.0%.ConclusionFixed saccadic movement latency and speed, randomized saccadic movement latency, precision and speed, pendular tracking gain, slow component angular speed, and optokinetic nystagmus gain in the digital vectonystagmography may show abnormalities in patients with possible diagnosis of peripheral vestibular dysfunction.

The 57th Annual Meeting of the American Academy of Neurology, Miami, Florida, April 9-16, 2005

The 57th Annual Meeting of the American Academy of Neurology, Miami, Florida, April 9-16, 2005

The relationship between the activities‐specific Balance Confidence Scale and the Dynamic Gait Index in peripheral vestibular dysfunction

People with vestibular dysfunction experience dizziness, vertigo and postural instability. The persistence of these symptoms may result in decreased balance confidence. The purpose of the present study was to examine the relationship between decreased balance confidence and gait dysfunction in patients with unilateral peripheral vestibular dysfunction. A retrospective review of 137 charts with the Activities-specific Balance Confidence (ABC) Scale and the Dynamic Gait Index (DGI) scores was completed. Spearman rank-order correlation analysis was performed of the total sample, by age group and by degree of vestibular weakness. A moderate correlation of r = 0.58 (p < 0.001) was found between the ABC Scale score and the DGI score in the total sample. Those with mild or moderate vestibular weakness had a correlation of r = 0.72 (p < 0.001) between the ABC Scale score and the DGI score, compared with a correlation of r = 0.48 in those with severe or total vestibular weakness. Decreased balance confidence and increased fall risk are critical issues for people with vestibular dysfunction. The effects of aging did not have a significant impact on the relationship. The correlation between balance confidence and gait dysfunction was stronger in those with mild or moderate vestibular weakness, although those with severe or total weakness were more disabled by their vestibular symptoms.

Repeatability of the Subjective Visual Vertical and Horizontal

The Subjective Visual Vertical [SVV] is the angle between the gravitational vertical axis and the position of a linear visual marker adjusted vertically by a subject. The Subjective Visual Horizontal [SVH] is similarly defined. Both SVV and SVH are reported to represent function of otoliths and vertical semicircular canals. Current practice of measuring SVV and SVH uses an average of multiple readings to obtain a mean value. This prospective study investigates repeatability of these tests in controls and patients with peripheral vestibular pathology. Twelve replicate readings of SVV and SVH were recorded in 17 controls, 9 patients with unilateral peripheral vestibular dysfunction [uPVD] and 10 patients with definite Meniere's disease [MD]. Control subjects repeated the measurements on day 8 and day 30 and patient groups repeated the measurements one hour later, due to limitations of compliance. Mean SVV/SVH and indicators of repeatability were computed and compared between patients and controls. Repeatabi...

Symptomatic high frequency/acceleration vestibular loss: consideration of a new clinical syndrome of vestibular dysfunction

ConclusionSymptomatic high frequency/acceleration vestibular loss is a distinct clinical entity that can be missed on conventional ENG with caloric testing. Under certain circumstances, symptomatic patients with a high frequency/acceleration vestibular loss should undergo an MSSC study for confirmation, if required.ObjectiveTo document that normal electronystagmography (ENG) with conventional bithermal caloric testing is inadequate for diagnosing clinically significant high frequency/acceleration vestibular loss.Material and methodsPatients with clinical symptoms and signs of persistent peripheral vestibular dysfunction despite normal conventional bithermal caloric testing on ENG underwent high frequency/acceleration horizontal magnetic scleral search coil (MSSC) eye movement studies. The clinical findings and results from audiometric tests, conventional ENG with bithermal caloric tests and MSSC tests were reviewed.ResultsEleven patients were identified as having an abnormal MSSC study, indicating a high frequency/acceleration vestibular loss consistent with their clinical history despite normal or equivocal bithermal caloric responses on conventional ENG. Although valuable, ENG caloric testing evaluates lateral semicircular canal function and should be considered a non-physiological test primarily of low frequency vestibular function. High frequency/acceleration head thrust testing clinically detected a “high frequency/acceleration vestibular loss” in 8/11(72.7%) cases.

Acute migrainous vertigo: clinical and oculographic findings

Migrainous vertigo (MV) is an increasingly recognized cause of episodic vertigo. However, the pathophysiology of MV is still a matter of speculation and it is not known to what extent the dysfunction is located in the central or peripheral vestibular system. The aim of this prospective study was to describe the clinical spectrum of acute MV and to clarify which structures of the vestibular system are involved. Testing of 20 patients with acute MV included neuro-otological examination, recording of spontaneous and positional nystagmus with 3D video-oculography, and audiometry. Pathological nystagmus was observed in 70% of patients during acute MV: six had isolated spontaneous nystagmus, five had isolated positional nystagmus and three had a combination of the two. Only a few patients showed additional ocular motor deficits. Imbalance was observed in all patients except one. Hearing was not affected in any patient during the attack. The findings during acute MV point to central-vestibular dysfunction in 10 patients (50%) and to peripheral vestibular dysfunction in three patients (15%). In the remaining seven patients (35%) the site of involvement could not be determined with certainty. MV should be considered in the differential diagnosis of vertigo with spontaneous and positional nystagmus and can present both as a central and a peripheral vestibular disorder.

Dizziness

<h2>Abstract</h2> Dizziness has many otological, neurological and medical causes, whereas the term ‘vertigo' is more specific and usually implies a vestibular disorder. Balance is maintained by sensory inputs from the visual, proprioceptive and vestibular systems. This information is integrated in the CNS and any mismatch between these sensory inputs can lead to vertigo. Dizziness from otological disorders often causes acute onset vertigo, whereas neurological causes often present with insidious imbalance. Common causes of dizziness include peripheral vestibular dysfunction, Benign positional paroxysmal vertigo, Ménière's syndrome and migraine. Clinical evaluation of dizziness should include otoscopy, tuning-fork tests, examination of eye movements, stance, gait and the Hallpike test. Investigations such as caloric testing and electro/videonystagmography help to confirm the presence of a lesion, lateralize it, and differentiate central from peripheral causes. After an acute vestibular insult, symptoms of dizziness get better by ‘compensation' that involves central mechanisms and substitution of sensory inputs. Acute vertigo is treated with vestibular sedatives, which should be tapered as soon as possible to allow vestibular compensation. Drug treatment is available for migraine-associated dizziness, Ménière's disease and central vestibular disorders causing oscillopsia. Dizziness from vestibular dysfunction can be effectively managed by vestibular rehabilitation exercises, either customized or generic (Cawthorne-Cooksey exercises). Recently, optokinetic stimulation has been used to promote compensation. Specific manoeuvres (Epley's) are very effective in benign positional paroxysmal vertigo. Management of vestibular disorders is now being consolidated in ‘one-stop' clinics that are piloted at various sites in the UK.

Virtual reality and vestibular rehabilitation: Seven-years experience

Objectives: Antivertiginous drugs, antihistaminics or vasodilators, are known to give temporary relief but literature suggests the counterproductive effects of these drugs. Once the severe acute symptoms subside the antivertiginous drug therapy should be stopped and the patient should be considered for vestibular rehabilitation therapy. Current rehabilitation efforts are intended to drive the nervous system to adapt to the disordered vestibular input: physiopathological basics of vestibular rehabilitation are based on mechanisms of vestibular compensation: an appropriately designed virtual reality (VR) experience could greatly increase the rate of compensation in these patients. Methods: To test the application of VR on our patients we used a particular “helmet” connected to a personal computer. The rehabilitation training is divided in 2 phases: “passive” and “active.” Since 1997, 908 patients had been submitted to the vestibular rehabilitation with VR. The patients were affected with: paroxysmal positional vertigo, monolateral peripheral vestibular dysfunction, bilateral peripheral vestibular deficit, central nervous system lesions, psychogenic vertigo. Results: Seventy-five percent of patients showed an improvement demonstrated by stabilometric data while 92% of patients reported an improvement of their symptoms. Patients with peripheral vertigo showed an improvement both of symptoms and objective data while patients with central vertigo showed an improvement in objective data not always accompanied by a regression in subjective symptoms. Conclusions: Correct execution of the exercises permits a mobility of the neck that activates compensation mechanisms through somato-esthesic channels in cervical muscles. This method could also show success in pediatric patients where a playful approach to therapy could be used.

Visual vertigo: an observational case series of eleven patients.

Dizziness is a common symptom which is frequently due to either peripheral or central vestibular dysfunction. However, some patients may lack typical signs suggesting a vestibular or cerebellar lesion and they mostly complain of vertigo or posture imbalance induced by visual stimulation. The symptoms immediately improve either on cessation of the visual input or upon closure of the eyes. Such a presentation is typical of visual vertigo. From 1993 to 2003, 242 patients were examined for either "vertigo" or "dizziness". The diagnosis of visual vertigo was based on both history and clinical examination and was present in 11 patients. Visual vertigo was diagnosed in 11/242 patients (4.5 %). Age range was 31 - 77 years (mean 47 years) with a sex ratio of 8 females for 3 males. Neuro-ophthalmological examination was normal in all cases. Visual vertigo is not a rare condition but the disease is underdiagnosed. The symptoms result from a mismatch between vestibular, proprioceptive and visual inputs. Neuro-ophthalmological, neurological and neuro-otological examination are often normal or not relevant and the diagnosis is largely based on history. It is important to recognize this entity because the symptoms might improve if the patients are treated with psycho-motor rehabilitation.

Outcomes after rehabilitation for adults with balance dysfunction

Badke MB, Shea TA, Miedaner JA, Grove CR. Outcomes after rehabilitation for adults with balance dysfunction. Arch Phys Med Rehabil 2004;85:227–33. Objectives To assess balance, dynamic gait, and dynamic visual acuity outcomes after a vestibular and balance rehabilitation program and to determine which variables were significantly associated with improved balance and ambulation. Design Retrospective case series. Setting Outpatient setting at a tertiary care facility. Participants Twenty patients who were seen for vestibular and balance therapy between July 1999 and June 2000. Interventions A customized exercise program was developed for each patient according to the results of the assessment and included the following interventions, as indicated: gaze stabilization, balance and gait training, and habituation exercises. Main outcome measures The Dynamic Gait Index (DGI), Berg Balance Scale (BBS), Dynamic Visual Acuity Test (DVAT), and computerized posturography (Sensory Organization Test [SOT]). Results The mean change scores for the DGI showed significant improvement for both patients with peripheral vestibular dysfunction and patients with central balance disorders. For the central balance disorders group, the BBS score also showed significant improvement. No difference was noted for pretherapy and posttherapy SOT scores between groups. The total group appeared to show an average improvement of more than 2 lines on the visual acuity chart on the clinical DVAT. Patients who were 66 years or older were 1.5 times more likely to score less than 20 on the DGI, and those whose pretherapy vertical dynamic visual acuity was 20/80 or worse were 1.3 times more likely to score less than 20 on the DGI. Conclusions Patients showed functional improvements in balance, visual acuity, and gait stability after balance and vestibular physical therapy. Age and pretherapy vertical dynamic visual acuity score influenced dynamic gait outcome after a balance rehabilitation program.

Head-shaking nystagmus in patients with a vestibular schwannoma.

The aim of this study was to calculate the sensitivity of the head-shake test for peripheral and central vestibular dysfunction associated with unilateral sporadic vestibular schwannoma and to discuss the feasibility of using the head-shake test as a screening test. The study group consisted of 102 patients with unilateral sporadic vestibular schwannomas, who were seen consecutively for preoperative vestibular assessment, including the head-shake test. The sensitivity of the head-shake test for vestibular schwannoma was found to be 22%, and the sensitivity and specificity of the head-shake test for canal paresis (>/=25%) were found to be 27% and 88%, respectively. Patients with abnormalities in the central vestibular system and with a greater canal paresis were more likely to have head-shake nystagmus, although, even for severe canal paresis, the sensitivity of the test remained low at 36%. The direction of nystagmus was found to be contra-lateral to the side of the tumour in 86% of patients. It was concluded that the head-shake test is of insufficient sensitivity to be used as a screening test either for vestibular schwannoma or for vestibular-system abnormalities associated with vestibular schwannoma. The deduction is made that the head-shake test is of insufficient sensitivity or specificity to be of clinical value as a screening test for vestibular dysfunction in a general population with symptoms of imbalance.

Relevance of plasma D-dimer measurement in patients with acute peripheral vertigo.

The aetiopathogenesis of acute unilateral peripheral vestibular dysfunction (APV), also known as vestibular neuritis, is still debated: the principal cause is viral infection with vascular factors second in importance. Plasmatic D-dimer, considered a plasmatic index of hypercoagulation, was measured in a group of 45 APV patients and in a group of 25 patients suffering from Ménière's disease. Measurements were taken both during the acute stage and after a four to six week period of pharmacological washout. The mean D-dimer levels were significantly higher than those measured in the controls both during the acute phase (301 SD161 vs 202 SD113 ng/mL) and after follow up (304 SD211 vs 192 SD111 ng/mL) (p = 0.008). Moreover, during the acute stage 23 of the APV patients (51.1 per cent) had plasmatic D-dimer levels above the upper normal limit (i.e.: <300 ng/mL), compared to four of those with Ménière's disease (16 per cent). Our results lead us to postulate an involvement of the haemostatic system in APV.

Peripheral vestibular dysfunction in chronic fatigue syndrome

Objective: To report left-sided peripheral vestibular failure as the cause of dizziness in a 12-year-old boy diagnosed as having chronic fatigue syndrome (CFS). Design: Retrospective case report with review of literature and discussion. Setting: Tertiary children's hospital. Conclusion: We recommend proper vestibular assessment for CFS patients presenting with dizziness, as effective treatment for peripheral vestibular disorder exists in the form of balance rehabilitation exercises.

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Caloric testing is one of the most valuable examinations for evaluating vestibular function. Recently, air caloric stimulation has been more widely utilized than irrigation with water. Using air has several advantages as follows; 1. possible to be performed by a clinical laboratory technician only, and 2. possible to be applied to patients with otitis media, 3. possible to avoid discomfort caused by water in the external ear canal. However, there is no agreement about the detailed method of air caloric stimulation. This study intended to establish the stimulation standards of the air caloric testing. We studied 16 normal subjects as well as 6 patients with unilateral peripheral vestibular dysfunction. Bi-thermal (30°C and 44°C) and uni-thermal (20°C) methods were applied using air and water stimulation, respectively.With regard to maximum slow phase velocity, air and water caloric stimulation could deliver corresponding response, under the conditions of 20°C and 44°C temperature. However, a significant difference was observed at 30°C, which showed a weaker response using air caloric stimulation. Caloric unilateral weakness was similarly demonstrated by air as well as water irrigation. And there was no significant difference in CP% between air and water caloric stimulation. Air caloric testing seemed to be an alternative to the traditional method of water irrigation, though the appropriate value for the low temperature in cases receiving bi-thermal stimulation remains controversial.

The origin of contraversive pushing: evidence for a second graviceptive system in humans.

Stroke patients may exhibit the peculiar behavior of actively pushing away from the nonhemiparetic side, leading to lateral postural imbalance and a tendency to fall toward the paralyzed side. This phenomenon has been called the "pusher syndrome." The current study analyzes the mechanism leading to contraversive pushing. The subjective postural vertical (SPV) and subjective visual vertical (SVV) were determined in five consecutively admitted patients with severe contraversive pushing and in controls. Whereas adjustment of the SPV reflects the perceived upright orientation of the body, the SVV provides a sensitive and direction-specific measurement of peripheral and central vestibular dysfunction. The deficit leading to contraversive pushing is an altered perception of the body's orientation in relation to gravity. Pusher patients experience their body as oriented "upright" when it is tilted 18 degrees to the nonhemiparetic, ipsilesional side. In contrast, perception of the SVV was undisturbed. A separate pathway seems to be present in humans for sensing the orientation of gravity apart from the one for orientation perception of the visual world. This second graviceptive system decisively contributes to humans' control of upright body posture. Contraversive pushing occurring after stroke lesions may represent the behavioral correlate of a disturbed neural representation of this system.

Orientational evaluation of otolith function by eye counter-rolling in patients with various kinds of vertigo

Measurement of ocular counterrolling (OCR) is well known as a simple method to evaluate the peripheral vestibular organ, especially the otolith organ. But it has rarely been used because of the difficulty in differentiating between pathologically reduced OCR and the wide physiological variation of this parameter. In this study, the OCR of 55 patients with unclarified vertigo (n = 20), vestibular neuronitis (n = 15), Menière's disease (n = 10), and benign paroxysmal positional nystagmus (n = 10) were evaluated and compared to a control group (n = 30) with the intention of diagnosing peripheral vestibular dysfunction and establishing a differential diagnosis. The test sequence was carried out with Vesta goggles by Panares and included head tilts of 5 degrees, 15 degrees, and 30 degrees to the left and right. The results show a significantly reduced OCR in patients suffering from peripheral vestibular disorders when compared to the control group. There is no specific finding for a specific type of vestibular lesion, but otolith function is affected in several disorders as measured by ocular counterrolling.