*  "Effectiveness of conventional versus virtual reality based vestibular " by Dara Meldrum
... and found that patients with vestibular disease enjoyed balance exercises on the NWFP™ and perceived that it was beneficial. ... based vestibular rehabilitation or six weeks of conventional vestibular rehabilitation. Intention to treat analysis indicated ... In conclusion this thesis presents novel findings on the effectiveness of virtual reality in vestibular rehabilitation and on ... The increasing prevalence of technology worldwide has produced opportunities for professionals in the area of vestibular ...
  https://epubs.rcsi.ie/phdtheses/128/
*  Vestibular Disease because of ear infections
My rescued bulldog has two bad ear infections which the vet said has contributed to Vestibular Disease. He hangs to the right ... My rescued bulldog has two bad ear infections which the vet said has contributed to Vestibular Disease. He hangs to the right ... Has anyone had experience with this disease. I was wondering how long it took to regain balance?. ...
  http://www.englishbulldognews.com/forums/your-bulldog-s-health/562-vestibular-disease-ear-infections.html
*  Effectiveness of Computer Assisted Training for Older People With Vestibular Dysfunction - Full Text View - ClinicalTrials.gov
Condition or disease Intervention/treatment Dysfunction of Vestibular System Procedure: Computer-training ... In patients with vestibular dysfunction, vestibular rehabilitation (VR) can reduce fall risk. Several studies show however that ... Central vestibular dysfunction without other co-morbidities (eg. Parkinson's, Stroke). *Mixed peripheral and central vestibular ... Effectiveness of Computer Assisted Training in Vestibular Rehabilitation for Older Patients With Vestibular Dysfunction. ...
  https://clinicaltrials.gov/ct2/show/NCT01344408?recr=Open&cond=%22Vertigo%22&rank=17
*  Vestibular Disease
... occurs when the nerves have difficulty performing these functions. There are two types of vestibular disease ... How is vestibular disease treated? To diagnose vestibular disease, the veterinarian carefully performs diagnostic tests, ... with peripheral vestibular disease being more common. Peripheral vestibular disease is caused by disorders of the inner ear ( ... Any animal with a vestibular system can suffer from vestibular disease; this ranges from fish and birds to dogs and cats. A ...
  http://www.dansvilleanimalhospital.com/services/pet-health/neurological-health-/vestibular-disease/
*  Vestibular rehabilitation therapy: review of indications, mechanisms, and key exercises.
... is an exercise-based treatment program designed to promote vestibular adaptation and substitution. The goals of VRT are 1) to ... It is not always possible for the physician to determine whether the patient's complaints are due to stable vestibular disease ... The overall mechanisms of recovery from vestibular lesions are vestibular adaptation and vestibular substitution. The ... Vestibular function after acute vestibular neuritisRestor Neurol NeurosciYear: 201028374620086281. 13. Kim HA,Hong JH,Lee H,Yi ...
  http://www.biomedsearch.com/nih/Vestibular-rehabilitation-therapy-review-indications/22259614.html
*  Vestibular Rehabilitation for Patients With Fall-related Wrist Fractures - Full Text View - ClinicalTrials.gov
Vestibular rehabilitation, twice a week for 9 weeks. Other: Vestibular rehabilitation The intervention program comprises of ... Vestibular asymmetry. Vestibular rehabilitation. Fall-related wrist fractures. Patients 50 years or older. ... The aim of this study is therefore to find out if vestibular rehabilitation can have any effect on vestibular function among ... Vestibular rehabilitation programs were first developed in the forties, originally used for peripheral vestibular disorder, in ...
  https://clinicaltrials.gov/ct2/show/NCT00988572
*  Third International Masterclass
Therefore, on day one these topics and the most frequent peripheral, central and functional vestibular diseases are covered by ... Peripheral vestibular disorders including their new classification. M. Strupp 16:40. Central vestibular disorders, including ... Vestibular rehabilitation. All professionals in the field of vestibular and ocular motor. disorders can attend the courses. ... central and functional vestibular disorders. The basis for the diagnosis of vestibular signs and symptoms are a profound ...
  http://www.klinikum.uni-muenchen.de/European-Dizzynet/de/3rd-Masterclass/index.html
*  How do you treat vestibular disease in dogs? | Reference.com
Treatment of vestibular disease in dogs is a combination of treating both the symptoms of the condition and any underlying ... Treatment of vestibular disease in dogs is a combination of treating both the symptoms of the condition and any underlying ... Vestibular disease in dogs is usually idiopathic, meaning its cause is unknown. Some potential causes include circulation or ... Vestibular disease may be prevented by avoiding head trauma and the overuse of certain medications. Neomycin and aminoglycoside ...
  https://www.reference.com/pets-animals/treat-vestibular-disease-dogs-581f08ab183510ff
*  Recovery of Visual Acuity in People With Vestibular Deficits - Full Text View - ClinicalTrials.gov
Autoimmune Diseases of the Nervous System. Demyelinating Diseases. Peripheral Nervous System Diseases. Neuromuscular Diseases. ... Ear Diseases. Otorhinolaryngologic Diseases. Otorhinolaryngologic Neoplasms. Cranial Nerve Diseases. Nervous System Diseases. ... Vestibular Neuronitis Vestibular Neuronitis, Bilateral Vestibular Schwannoma Other: Control exercises Other: gaze stabilization ... Patient had to have either a unilateral vestibular or bilateral vestibular hypofunction defined as follows: Unilateral ...
  https://clinicaltrials.gov/ct2/show/NCT00411216?cond=%22Acoustic+neuroma%22&rank=9
*  Diagnosis and Treatment of Vestibular Disease - WSAVA2013 - VIN
... can lead to peripheral vestibular disease. You will encounter acute to peracute idiopathic vestibular disease in both dogs and ... So, if you have a patient with clinical signs of central vestibular disease and the head tilt is on the opposite side of where ... peripheral vestibular disease, and that both resting nystagmus and veering/leaning to one side were significantly more common ... The most common cause of peripheral vestibular disease in dogs and cats is otitis media/interna. Toxins and trauma are ...
  http://www.vin.com/apputil/content/defaultadv1.aspx?pId=11372&catId=35308&id=5709909&ind=191&objTypeID=17
*  VESTIBULAR DISEASES
... Ear infection:. Infection of the middle/inner ear is a common cause of vestibular disease in the dog. Most ... Canine idiopathic vestibular syndrome:. This is also a common cause of vestibular disease in the dog. Another name is geriatric ... Therefore a problem in the inner ear or one in the brain can affect the vestibular system. The phrase 'vestibular disease' is a ... Signs of vestibular disease include ataxia, head tilt, and abnormal nystagmus. A wide-based stance and swaying of the head and ...
  http://www.canine-epilepsy-guardian-angels.com/vestibular_diseases.htm
*  vestibular disease Archives - iMedicalApps
iMedicalApps is an independent online medical publication for medical professionals, patients, and analysts interested in mobile medical technology and health care apps. Our physician editors lead a team of physicians, allied health professionals, medical trainees, and mHealth analysts in providing reviews, research, and commentary of mobile medical technology. Our publication is heavily based on our own experiences in the hospital and clinic setting.. ...
  https://www.imedicalapps.com/tag/vestibular-disease/
*  THERAPY OF FUNCTIONAL DISORDERS OF THE CRANIOVERTEBRAL JOINTS IN VESTIBULAR DISEASES
... www.chiro.org/research/ABSTRACTS/Vestibular_Diseases.shtml ... Disorders of the Craniovertebral Joints in Vestibular Diseases ... Craniovertebral Joints in Vestibular Diseases This section was compiled by Frank M. Painter, D.C.. Send all comments or ... Two of the 28 patients showed persistent relief of symptoms and normalisation of cervical motility whereas the vestibular ... One patient with persistent vestibular dysfunction showed recurrent malfunction of the upper cervical spine and vertigo. In our ...
  http://www.chiro.org/research/ABSTRACTS/Vestibular_Diseases.shtml
*  Cochlear Implantation in Ménière's Disease | Vestibular Disorders Association
Meniere's disease will have the similar hearing improvements with cochlear implants as CI patients without Meniere's disease. ... its effect on the auditory and vestibular symptoms in patients with Ménière's disease (MD) has not been firmly established. ... Main Outcomes and Measures Pre-CI and post-CI sentence testing scores, frequency and severity of MD vestibular and auditory ... A study to determine if patients with Meniere's disease will have the similar hearing improvements with cochlear implants as CI ...
  http://vestibular.org/news/05-02-2014/cochlear-implantation-m%C3%A9ni%C3%A8re%E2%80%99s-disease
*  Vestibular Diseases Global Clinical Trials Review, H2, 2015
2015 Vestibular Diseases Global Clinical Trials Review, H2, 2015 Summary GlobalData's clinical trial report, ... Vestibular Diseases Global Clinical Trials Review, H2, 2015. Summary. GlobalData's clinical trial report, "Vestibular Diseases ... Unaccomplished Trials of Vestibular Diseases*Table Vestibular Diseases Therapeutics, Global, Withdrawn Clinical Trials, 2015* ... Top Companies Participating in Vestibular Diseases Therapeutics Clinical Trials*Table Figure 19: Vestibular Diseases ...
  https://www.marketresearch.com/GlobalData-v3648/Vestibular-Diseases-Global-Clinical-Trials-9293156/
*  Common Diseases in Older Dogs: Idiopathic Vestibular Disease | PEDIGREE®
... he may have idiopathic vestibular disease. The cause of this disease is unknown, and it can appear suddenly in older and, ... Does your dog have idiopathic vestibular disease?. If you suspect your dog has this condition, it's important to have him ... Dogs who do not fully recover from vestibular disease can usually adapt to the head tilt and other symptoms, and continue to ... If your dog has idiopathic vestibular disease he will feel extremely "seasick" and may have a hard time walking or even ...
  https://www.pedigree.com/dog-care/health/common-diseases-in-older-dogs-idiopathic-vestibular-disease
*  Vestibular Disease - Mar Vista Animal Medical Center
Signs of vestibular disease include: ataxia or dizzyness, motion sickness, nystagmus, circling, head tilt, falling to one side ... The vestibular apparatus allows us to walk, even run, on very uneven ground without falling, helps us know when we need to ... IDIOPATHIC DISEASE. Canine idiopathic vestibular disease (also called "Old dog vestibular disease") and, its feline counterpart ... IDIOPATHIC VESTIBULAR DISEASE IS THE MOST COMMON FORM. OF VESTIBULAR DISEASE IN DOGS AND CATS. ...
  http://marvistavet.com/vestibular-disease.pml
*  Depersonalisation/derealisation symptoms in vestibular disease | Journal of Neurology, Neurosurgery & Psychiatry
In vestibular disease, frequent experiences of derealisation may occur because distorted vestibular signals mismatch with the ... derealisation symptoms in patients with peripheral vestibular disease and experimentally to induce these symptoms by vestibular ... Methods: 121 healthy subjects and 50 patients with peripheral vestibular disease participated in the study. For comparison with ... Feelings of unreality can be evoked by disorienting vestibular stimulation.. Objective: To identify the prevalence of ...
  http://jnnp.bmj.com/content/77/6/760
*  Old dog vestibular disease?
This page has good basic info on vestibular.. There are also forums just for owners of pets that have experienced vestibular ... He's on meclazine (sp) for the vestibular symptoms but I guess he gets to come home after I get done here at work. Now I gotta ... I've worked with vestibular dogs, and it can be scary seeing that if you don't know what is wrong. ... The vet said it was likely old dog vestibular syndrome which has a good prognosis. He also mentioned that he didn't have the ...
  http://www.pitbullforum.com/viewtopic.php?p=2008453
*  Go to Central vestibular disease.
Central vestibular disease. Clinical signs similar to peripheral vestibular disease but with associated depressed mental status ... Soft tissue surgery refers to any type of surgery for treatment of diseases which are not orthopaedic or neurologic. As such, ...
  https://www.fitzpatrickreferrals.co.uk/glossary/central-vestibular-disease/
*  Old dog vestibular disease? - Page 2
Just saw this article posted on Bark magazine - [url]http://thebark.com/content/idiopathic-or-"old-dog"-vestibular-disease[/url ...
  http://www.pitbullforum.com/viewtopic.php?f=5&t=153492&p=2008806
*  Can vestibular-evoked myogenic potentials help differentiate Ménière disease from vestibular migraine? - PubMed - NCBI
Can vestibular-evoked myogenic potentials help differentiate Ménière disease from vestibular migraine?. Zuniga MG1, Janky KL, ... Can Vestibular-Evoked Myogenic Potentials Help Differentiate Ménière Disease from Vestibular Migraine? ... Can Vestibular-Evoked Myogenic Potentials Help Differentiate Ménière Disease from Vestibular Migraine? ... Vestibular-evoked myogenic potential (VEMP) results in the ears (circles) of controls, vestibular migraine (VM), and Ménière ...
  https://www.ncbi.nlm.nih.gov/pubmed/22267492
*  Deafness, Autosomal Recessive 4, with Enlarged Vestibular Aqueduct disease: Malacards - Research Articles, Drugs, Genes,...
Global: Genetic diseases Rare diseases Anatomical: Ear diseases Neuronal diseases See all MalaCards categories (disease lists) ... Deafness, Autosomal Recessive 4, with Enlarged Vestibular Aqueduct Categories: Genetic diseases, Rare diseases, Ear diseases, ... ClinVar genetic disease variations for Deafness, Autosomal Recessive 4, with Enlarged Vestibular Aqueduct:. 6 (show top 50) ( ... DFNB4 is associated with an enlarged vestibular aqueduct. Disease Ontology : 12 An autosomal recessive nonsyndromic deafness ...
  http://www.malacards.org/card/deafness_autosomal_recessive_4_with_enlarged_vestibular_aqueduct
*  Vestibular Disease in Cats Symptoms, Treatments | Peripheral, Central Types of Vestibular Disease in Cats
Signs of vestibular diseases in cats are in-coordination of body parts, dizzy spells, falling down frequently. Causes can be ... Vestibular Disease in Cats Treatment Vestibular disease is of two kinds, peripheral and central. The course of treatment is ... Feline Vestibular Disease The vestibular system in cats is important for it keeps the head and body in the correct position ... The onset of the disease is very sudden and vestibular disease in cats is symptomised by an in-coordination of body parts, ...
  http://www.pethealthandcare.com/cat-health/cat-vestibular-disease.html
*  Genetic Analysis of Hereditary Disorders of Hearing and Balance | Clinical Research Trial Listing ( Sensorineural hearing loss ...
... vestibular disease in clinical trial on Genetic Analysis of Hereditary Disorders of Hearing and Balance ... The peripheral auditory and vestibular systems share many common features in both health and disease, and many hereditary ... In contrast, the molecular mechanisms underlying familial disorders affecting peripheral vestibular function appear to be more ... hearing loss disorders also affect vestibular function. The purpose of this study is to identify genes and mutations causing ...
  http://www.centerwatch.com/clinical-trials/listings/18166/sensorineural-hearing-loss-genetic-analysis-hereditary-disorders/?&radius=50

(1/298) 3D MRI of the membranous labyrinth. An age related comparison of MR findings in patients with labyrinthine fibrosis and in persons without inner ear symptoms.

PURPOSE: We compared MRI of the membranous labyrinth in patients with chronic non-neoplastic inner ear disease and MR signs of labyrinthine fibrosis and controls depending on their age, in order to establish whether there were any MR differences regarding patient age groups, control age groups and between the patients and controls themselves. MATERIALS AND METHODS: Clinical ENT examinations as well as a T2* weighted 3D CISS (Constructive Interference in Steady State) sequence with a slice thickness of 0.7 mm were performed. Our collective was subdivided as follows: 0-19 years (10 controls, 3 patients with chronic non-neoplastic inner ear disease), 20-49 years (55 controls, 8 patients), 50 years and older (40 controls, 22 patients). Detectability of labyrinthine structures (e.g. cochlea, vestibule, semicircular canals) and filling defects were evaluated. RESULTS: In the 3 age-groups of the control collective no significant differences were observed in the membranous labyrinth. However differences concerning labyrinthine detectability emerged between controls and patients in both the 20-49 years and 50 years and older age groups. In the patient collective the 3 age groups showed no significant discrepancy in the mean number of lesions. CONCLUSION: Filling defects of the membranous labyrinth on 3D CISS MR images are pathological even in older persons. We would therefore recommend high resolution T2* weighted MRI in the case of suspected labyrinthine fibrosis.  (+info)

(2/298) Pontine lesions mimicking acute peripheral vestibulopathy.

OBJECTIVES: Clinical signs of acute peripheral vestibulopathy (APV) were repeatedly reported with pontine lesions. The clinical relevance of such a mechanism is not known, as most studies were biased by patients with additional clinical signs ofbrainstem dysfunction. METHODS: Masseter reflex (MassR), blink reflex (BlinkR), brainstem auditory evoked potentials (BAEPs), and DC electro-oculography (EOG) were tested in 232 consecutive patients with clinical signs of unilateral APV. RESULTS: Forty five of the 232 patients (19.4%) had at least one electrophysiological abnormality suggesting pontine dysfunction mainly due to possible vertebrobasilar ischaemia (22 patients) and multiple sclerosis (eight patients). MassR abnormalities were seen in 24 patients, and EOG abnormalities of saccades and following eye movements occurred in 22 patients. Three patients had BlinkR-R1 abnormalities, and one had delayed BAEP waves IV and V. Clinical improvement was almost always (32 of 34 re-examined patients) associated with improvement or normalisation of at least one electrophysiological abnormality. Brain MRI was done in 25 of the 44 patients and confirmed pontine lesions in six (two infarcts, three inflammations, one tumour). CONCLUSIONS: Pontine dysfunction was suggested in 45 of 232 consecutive patients with clinical signs of APV on the basis of abnormal electrophysiological findings, and was mainly attributed to brainstem ischaemia and multiple sclerosis. The frequency of pontine lesions mimicking APV is underestimated if based on MRI established lesions only.  (+info)

(3/298) EMG responses to free fall in elderly subjects and akinetic rigid patients.

OBJECTIVES: The EMG startle response to free fall was studied in young and old normal subjects, patients with absent vestibular function, and patients with akinetic-rigid syndromes. The aim was to detect any derangement in this early phase of the "landing response" in patient groups with a tendency to fall. In normal subjects the characteristics of a voluntary muscle contraction (tibialis anterior) was also compared when evoked by a non-startling sound and by the free fall startle. METHODS: Subjects lay supine on a couch which was unexpectedly released into free fall. Latencies of multiple surface EMG recordings to the onset of free fall, detected by a head mounted linear accelerometer, were measured. RESULTS AND CONCLUSIONS: (1) EMG responses in younger normal subjects occurred at: sternomastoid 54 ms, abdominals 69 ms, quadriceps 78 ms, deltoid 80 ms, and tibialis anterior 85 ms. This pattern of muscle activation, which is not a simple rostrocaudal progression, may be temporally/spatially organised in the startle brainstem centres. (2) Voluntary tibialis EMG activation was earlier and stronger in response to a startling stimulus (fall) than in response to a non-startling stimulus (sound). This suggests that the startle response can be regarded as a reticular mechanism enhancing motor responsiveness. (3) Elderly subjects showed similar activation sequences but delayed by about 20 ms. This delay is more than can be accounted for by slowing of central and peripheral motor conduction, therefore suggesting age dependent delay in central processing. (4) Avestibular patients had normal latencies indicating that the free fall startle can be elicited by non-vestibular inputs. (5) Latencies in patients with idiopathic Parkinson's disease were normal whereas responses were earlier in patients with multiple system atrophy (MSA) and delayed or absent in patients with Steele-Richardson-Olszewski (SRO) syndrome. The findings in this patient group suggest: (1) lack of dopaminergic influence on the timing of the startle response, (2) concurrent cerebellar involvement in MSA may cause startle disinhibition, and (3) extensive reticular damage in SRO severely interferes with the response to free fall.  (+info)

(4/298) Sympathetic contralateral vestibulopathy after unilateral zoster oticus.

A unique case of initially right sided varicella zoster induced Ramsay-Hunt syndrome with complete vestibular loss is reported. The patient subsequently developed deficits of the left vestibule 5 months later. An autoimmune pathogenesis of the left vestibular failure rather than bilateral varicella zoster infection was suggested by the following data: (1) no evidence of vesicular eruptions on the left auricle and the virtual absence of antiviral antibodies after onset of bilateral vestibulopathy; (2) prompt response of the left vestibule to immunosuppressive therapy with corticosteroids; and (3) presence of atypical nervous tissue specific autoantibodies against a 45 kDa protein.  (+info)

(5/298) Probability of bilateral disease in people presenting with a unilateral vestibular schwannoma.

BACKGROUND: Some 4%-5% of those who develop vestibular schwannomas have neurofibromatosis type 2 (NF2). Although about 10% of these patients present initially with a unilateral vestibular schwannoma, the risk for a patient with a truly sporadic vestibular schwannoma developing contralateral disease is unknown. METHODS: A United Kingdom survey of 296 patients with NF2 was reviewed for laterality of vestibular schwannoma at presentation and the presence of other NF2 related features. The time to presentation of bilateral disease was calculated for patients presenting with a unilateral tumour. Mutation analysis of the NF2 gene was carried out on all available cases presenting initially with unilateral disease. RESULTS: Of 240 patients with NF2 with vestibular schwannomas, 45 (18%; 32 sporadic, 13 familial) had either a unilateral tumour or delay in detection between the first and contralateral tumours. Among those tested for NF2 mutations, eight of 27 and nine of 13 were identified among sporadic and familial cases respectively. Sporadic cases showed a high female to male ratio and 19 of 32 have not as yet developed a contralateral tumour (mean 4.1 years after diagnosis of the first). Thirteen of 32 sporadic patients developed a contralateral tumour (mean 6.5 years after the first tumour diagnosis, range 0-22 years) compared with 11 of 13 familial patients (mean delay 5 years, range 0-16 years). Seven of the 45 patients had neither a family history of NF2 nor evidence of related tumours at initial presentation (six before the age of 35 years). CONCLUSION: The risk of patients with sporadic unilateral vestibular schwannomata developing a contralateral tumour in the absence of family history or other features of NF2 is low, but those presenting with other neurogenic tumours in addition to vestibular schwannoma are at high risk of harbouring an NF2 mutation in at least a proportion of their somatic cells.  (+info)

(6/298) Postural characteristics of diabetic neuropathy.

OBJECTIVE: To explore the posturographic correlates of diabetic neuropathy by comparing the performances of three groups of diabetic patients (severe, moderate, and absent neuropathy) with those of normal subjects and four clinical control groups. RESEARCH DESIGN AND METHODS: Using the Interactive Balance System (Tetrax, Ramat Gan, Israel), based on the assessment of the interaction of vertical pressure fluctuations on four independent platforms, one for each heel and toe part, respectively, posturographic examinations were given to 28 diabetic patients (8 with severe, 12 with moderate, and 8 with no peripheral neuropathy), 30 normal control subjects, and a clinical control group of 52 patients (14 with stage II Parkinson's disease, 13 with brain damage, 7 with whiplash, and 19 with peripheral vestibular pathology). The following posturographic parameters were evaluated; 1) general stability; 2) Fourier analysis showing patterns of sway intensity within eight frequency bands between 0.1 and 3 Hz; 3) weight distribution; 4) synchronization of sway; and 5) performance patterns for eight positions, requiring closure of eyes and standing on an elastic surface, as well as left, right, back, and downward head turns. RESULTS: For positions with closed eyes, diabetic patients with severe and moderate neuropathy were significantly less stable than normal subjects and diabetic patients without neuropathy, but diabetic patients with severe and moderate neuropathy turned out to be as equally unstable as clinical control subjects. However, for sway intensity within the band of 0.5 to 1.00 Hz on positions with lateral head turn with occluded vision, neuropathic diabetic patients performed significantly worse than did both normal and clinical control subjects. The same posturographic parameter also differed significantly between normal subjects and diabetic patients without neuropathy. CONCLUSIONS: As reported in previous studies, general instability in diabetic neuropathy is not a sufficiently characteristic correlate of the syndrome. On the other hand, spectral analysis of sway on stressful positions involving head turning appears to differentiate diabetic neuropathy from other disorders involving postural disturbances.  (+info)

(7/298) A new mouse insertional mutation that causes sensorineural deafness and vestibular defects.

This article describes a new recessive insertional mutation in the transgenic line TgN2742Rpw that causes deafness and circling behavior in mice. Histologic analysis revealed virtually complete loss of the cochlear neuroepithelium (the organ of Corti) in adult mutant mice. In association with the neuroepithelial changes, there is a dramatic reduction of the cochlear nerve supply. Adult mutants also show morphological defects of the vestibular apparatus, including degeneration of the saccular neuroepithelium and occasional malformation of utricular otoconia. Audiometric evaluations demonstrated that the mice displaying the circling phenotype are completely deaf. Molecular analysis of this mutant line revealed that the transgenic insertion occurred without creating a large deletion of the host DNA sequences. The mutant locus was mapped to a region on mouse chromosome 10, where other spontaneous, recessive mutations causing deafness in mice have been mapped.  (+info)

(8/298) Influence of surgical plugging on horizontal semicircular canal mechanics and afferent response dynamics.

Mechanical occlusion of one or more of the semicircular canals is a surgical procedure performed clinically to treat certain vestibular disorders and used experimentally to assess individual contributions of separate canals and/or otoliths to vestibular neural pathways. The present experiments were designed to determine if semicircular canal afferent nerve modulation to angular head acceleration is blocked by occlusion of the endolymphatic duct, and if not, what mechanism(s) might account for a persistent afferent response. The perilymphatic space was opened to gain acute access to the horizontal canal (HC) in the oyster toadfish, Opsanus tau. Firing rate responses of HC afferents to sinusoidal whole-body rotation were recorded in the unoccluded control condition, during the process of duct occlusion, and in the plugged condition. The results show that complete occlusion of the duct did not block horizontal canal sensitivity; individual afferents often exhibited a robust firing rate modulation in response to whole-body rotation in the plugged condition. At high stimulus frequencies (about >8 Hz) the average sensitivity (afferent gain; spikes/s per degrees /s of head velocity) in the plugged condition was nearly equal to that observed for unoccluded controls in the same animals. At low stimulus frequencies (about <0.1 Hz), the average sensitivity in the plugged condition was attenuated by more than two orders of magnitude relative to unoccluded controls. The peak afferent firing rate for sinusoidal stimuli was phase advanced approximately 90 degrees in plugged canals relative to their control counterparts for stimulus frequencies approximately 0.1-2 Hz. Data indicate that afferents normally sensitive to angular velocity in the control condition became sensitive to angular acceleration in the plugged condition, whereas afferents sensitive to angular acceleration in the control condition became sensitive to the derivative of acceleration or angular jerk in the plugged condition. At higher frequencies (>8 Hz), the phase of afferents in the plugged condition became nearly equal, on average, to that observed in controls. A three-dimensional biomechanical model of the HC was developed to interpret the residual response in the plugged condition. Labyrinthine fluids were modeled as incompressible and Newtonian; the membranous duct, osseous canal and temporal bone were modeled as visco-elastic materials. The predicted attenuation and phase shift in cupular responses were in close agreement with the observed changes in afferent response dynamics after canal plugging. The model attributes the response of plugged canals to labyrinthine fluid pressure gradients that lead to membranous duct deformation, a spatial redistribution of labyrinthine fluids and cupular displacement. Validity of the model was established through its ability to predict: the relationship between plugged canal responses and unoccluded controls (present study), the relationship between afferent responses recorded during mechanical indentation of the membranous duct and physiological head rotation, the magnitude and phase of endolymphatic pressure generated during HC duct indentation, and previous model results for cupular gain and phase in the rigid-duct case. The same model was adjusted to conform to the morphology of the squirrel monkey and of the human to investigate the possible influence of canal plugging in primates. Membranous duct stiffness and perilymphatic cavity stiffness were identified as the most salient model parameters. Simulations indicate that canal plugging may be the most effective in relatively small species having small labyrinths, stiff round windows, and stiff bony perilymphatic enclosures.  (+info)



  • auditory
  • What is most important for purposes of clinical usage is that you understand the concept of how the vestibular (primarily) and auditory system operates. (vin.com)
  • Importance Though the effects of cochlear implantation (CI) on patients with hearing loss has been well described, its effect on the auditory and vestibular symptoms in patients with Ménière's disease (MD) has not been firmly established. (vestibular.org)
  • Objectives To determine whether CI in patients with MD improves hearing performance as measured by standard post-CI audiometric testing and to describe the impact of CI on subjective auditory and vestibular quality-of-life measures. (vestibular.org)
  • Main Outcomes and Measures Pre-CI and post-CI sentence testing scores, frequency and severity of MD vestibular and auditory symptoms via the MD Functional Level Scale (FLS), and hearing quality of life via the Hearing Handicap Index were reviewed. (vestibular.org)
  • Conclusions and Relevance Patients with MD who undergo CI are capable of achieving substantial receptive communication improvement comparable to the gains experienced by patients without MD. Implantation seems to neither adversely alter the natural history of vestibular function nor notable exacerbate auditory symptoms. (vestibular.org)
  • Meniere's
  • A study to determine if patients with Meniere's disease will have the similar hearing improvements with cochlear implants as CI patients without Meniere's disease. (vestibular.org)
  • These symptoms are not symptoms of Meniere's disease per se, but rather are side effects resulting from failure of the organ of hearing and balance, and include nausea, vomiting, and sweating-which are typically symptoms of vertigo, and not of Ménière's. (wikipedia.org)
  • EH, in turn, is strongly associated with developing MD, but not everyone with EH develops MD: "The relationship between endolymphatic hydrops and Meniere's disease is not a simple, ideal correlation. (wikipedia.org)
  • lesion
  • If the vestibular signs have a central origin, there could be a tumor, vascular accident , infection (especially Rocky Mountain Spotted Fever) or other lesion in the brain. (marvistavet.com)
  • cochlear
  • These were: the response occurred ipsilateral to the ear stimulated, the click threshold was high, the response did not depend upon hearing (cochlear function) per se, it scaled in direct proportion to the level of tonic neck contraction, the response was small (although large compared to many evoked potentials) and required averaging, and only the initial positive-negative response (p13-n23 by latency) was actually vestibular-dependent. (wikipedia.org)
  • The corresponding subtypes of MD are called vestibular MD, showing symptoms of vertigo, and cochlear MD, showing symptoms of hearing loss and tinnitus. (wikipedia.org)
  • signals
  • In vestibular disease, frequent experiences of derealisation may occur because distorted vestibular signals mismatch with the other sensory input to create an incoherent frame of spatial reference which makes the patient feel he or she is detached or separated from the world. (bmj.com)
  • This is because the hard floor will help reduce the risk of being awakened by vestibular signals caused by subtle movements during sleep. (advancedanimalchiropractic.com)
  • proprioceptive
  • Bárány theorized that the endolymph was sinking when it was cool and rising when it was warm, and thus the direction of flow of the endolymph was providing the proprioceptive signal to the vestibular organ. (wikipedia.org)
  • Problems with balance can occur when there is a disruption in any of the vestibular, visual, or proprioceptive systems. (wikipedia.org)
  • sudden
  • The onset of the disease is very sudden and vestibular disease in cats is symptomised by an in-coordination of body parts, dizzy spells, falling down frequently, walking drunkenly and stumbling without any obstruction, eyes that move continuously either up and down or side to side, a tilted head and rolling about. (pethealthandcare.com)
  • nerve
  • However, the cause of this condition is not fully understood, and in fact many different viruses may be capable of infecting the vestibular nerve. (wikipedia.org)
  • In 1992 Colebatch and Halmagyi reported a patient with a short latency response to loud clicks studied using a modified recording site (the sternocleidomastioid muscles: SCM) and which was abolished by selective vestibular nerve section. (wikipedia.org)
  • posture
  • Blocq's disease was first considered by Paul Blocq (1860-1896), who described this phenomenon as the loss of memory of specialized movements causing the inability to maintain an upright posture, despite normal function of the legs in the bed. (wikipedia.org)
  • neurophysiology
  • From 1984 until 1988 Minor then completed a research fellowship in vestibular neurophysiology at the University of Chicago Department of Pharmacological and Physiological Sciences, under the supervision of Jay M. Goldberg. (wikipedia.org)
  • In the third paper published by Paul Blocq, he was trying to determine the neurophysiology behind this disease by relating the cerebral cortex (the decision making) and the spinal cord (the decision executer). (wikipedia.org)
  • severity
  • In domestic dogs, while the acute generalized form of distemper has a high mortality rate, disease duration and severity depends mainly on the animal's age and immune status and virulence of the infecting strain of the virus. (wikipedia.org)
  • medial
  • Another clinically important vestibular tract is an ascending tract called the medial longitudinal fasciculus (MLF). (vin.com)
  • receptors
  • The dendritic zones of bipolar neurons for the vestibular neurons (located within the vestibular ganglia within the petrous temporal bone) are in synaptic contact with specialized "hair cells" (the hairs are actually stereocilia) in specific receptors. (vin.com)
  • These receptors in include the crista ampullaris, and maculae for vestibular function. (vin.com)
  • labyrinths
  • Experimental verification of "vestibular induced" depersonalisation/derealisation was assessed in 20 patients and 20 controls during caloric irrigation of the labyrinths. (bmj.com)
  • Stimulation
  • The fast phase going in the direction of the turn (stimulation direction) is really the only thing about vestibular function you need to memorize. (vin.com)
  • Feelings of unreality can be evoked by disorienting vestibular stimulation. (bmj.com)
  • Depersonalisation/derealisation symptoms are both different in quality and more frequent under conditions of non-physiological vestibular stimulation. (bmj.com)