PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Vestibular Function Tests”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources
PubMed2004

Head impulse test reveals residual semicircular canal function after vestibular neurectomy.

Meniere disease patients sometimes report vertiginous Meniere attacks after vestibular neurectomy that spares hearing. To determine why, the authors compared postsurgical semicircular canal function in nine patients with preserved hearing with that of a control group with no preservation of hearing. The three-dimensional head impulse test revealed residual posterior canal function in all patients with vertigo attacks (eight). The control patients had no residual canal function. Thus, residual vestibular function on the ipsilesional side may cause vertiginous Meniere attacks.

Adult↗
PubMed1995

Evaluation of vestibular and visual oculomotor function.

The visual system interacts synergistically with the vestibular system. A normally functioning vestibulo-ocular reflex is necessary but not sufficient for optimum visual acuity during head motion. Studies of dynamic visual acuity, the acuity achieved during relative motion of visual targets or of the observer, indicate that motion of images on the retina markedly compromises vision. The vestibulo-ocular reflex normally provides a substantial measure of stabilization of the retina during head movements, but purely vestibular compensatory eye movements are not sufficiently precise for optimal vision under all circumstances. Other mechanisms, including visual tracking, motor preprogramming, prediction, and mental set, interact synergistically to optimize the gain (eye velocity divided by head velocity) of compensatory head movements. All of these mechanisms are limited in their capacity to produce effective visual-vestibular interaction at higher rotational frequencies and velocities. It is under these conditions that vestibular deficits give rise to symptoms of oscillopsia. Patients having vestibular lesions exploit mechanisms of visual-vestibular interaction to compensate by substitution for deficient vestibular function. Thus, for accurate topographic clinical diagnosis of vestibular lesions, testing conditions should isolate purely vestibular responses. This may be done by testing reflex eye movements during passively generated rotations in darkness, or perhaps by testing during other types of motion under conditions of extreme frequency and velocity sufficient to attenuate the effects of visual-vestibular interaction. This article reviews clinical tests of vestibular function in relation to synergistic interactions with vision.

Aging↗
PubMedDate not supplied

Enlargement of the vestibular aqueduct.

Enlarged vestibular aqueduct, a recently identified anomaly, is typified by an enlarged vestibule, dilation of the ampullated portions of the horizontal and superior semicircular canals, an abnormal cochlea, and hearing loss. In the case described a 16-year-old boy had congenital hearing loss, episodic vertigo, and abnormal vestibular function testing. Tomograms and CT scans confirmed the diagnosis of bilaterally enlarged vestibular aqueducts. The vertiginous episodes decreased in frequency and severity with a no-salt-added diet. The authors conclude that the enlarged vestibular aqueduct is associated not only with other structural inner ear abnormalities and hearing loss, but also with abnormal vestibular function.

Adolescent↗
PubMed1989

Encephalopathy and vestibulopathy following short-term hydrocarbon exposure.

Dizziness, headaches, and weakness occurred among three men after short-term hydrocarbon exposure during improper welding procedures in a closed container. Symptoms were related to objective evidence of vestibular and cognitive dysfunction. Symptoms and abnormal test results persisted for 6 to 18 months. Simulation of the accident failed to demonstrate likely exposures except aliphatic hydrocarbons, well within the permissible exposure levels. Short-term exposures to neurotoxins may lead to long-term central nervous system abnormalities.

Accidents↗
PubMedDate not supplied

Intervestibular integration and its clinical consequences.

Research during the last twenty years has led to the conclusion that it is time for a more integrated and dynamic view on the physiological and pathophysiological process during clinical vestibular stimulation and perhaps also to reevaluate the interpretation of the findings. Ten patients with absence of function in one labyrinth were exposed to caloric and rotatory stimulation several times during the compensating period of 8 weeks. In the acute state, caloric irrigation of the normal ear with 30 degrees or rotatory stimulation toward the damaged ear resulted in total inhibition of the spontaneous nystagmus. In the chronic state the same investigation reversed the spontaneous nystagmus in the opposite direction. The investigation has shown that it is possible clinically to study the reactions of every single neuron in the vestibular ocular reflex pathway and in this way establish a more topographic diagnosis.

Acceleration↗
PubMed2004

The influence of voluntary tonic EMG level on the vestibular-evoked myogenic potential.

Vestibular-evoked myogenic potentials (VEMPs) are proposed as a reliable test to supplement the current vestibular test battery by providing diagnostic information about saccular and/or inferior vestibular nerve function. VEMPs are short-latency electromyograms (EMGs) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid muscle. VEMP amplitude is influenced by the EMG level, which must be controlled. This study examined the ability of subjects to achieve the EMG target levels over a range of target levels typically used during VEMP recordings. In addition, the influence of target EMG level on the latency and amplitude of the click- and tone-evoked VEMP was examined. The VEMP amplitude increased as a function of EMG target level, and the latency remained constant. EMG target levels ranging from 30 microV to 50 microV are suggested for clinical application of the VEMP.

Acoustic Stimulation↗
PubMed2004

[Characteristics of the response of vestibular evoked myogenic potentials to different stimulus modes].

OBJECTIVE: Vestibular evoked myogenic potential (VEMP) has been utilized in clinic to test the function of saccule. In the present study, 3 stimulus modes were applied to 21 normal adults and intended to draw in a clinical test protocol. METHODS: The normal latency and amplitude of VEMPs of 21 normal subjects were recorded and the ratio of bilateral amplitudes and asymmetry were calculated. RESULTS: The response to binaural clicks were similar to the response of the monaural clicks. The interindividual variation in amplitude were large, but the latency varied little. CONCLUSIONS: VEMPs is a stable myogenic potentials. Monaural and binaural clicks stimulus can be used in clinical practice. The latter is appropriate for normal hearing subjects. Amplitude measurement is probable to evaluate the asymmetry of bilateral saccular function and may reveal saccule lesion.

Acoustic Stimulation↗
PubMed1991

Altered coriolis stress susceptibility in essential hypertension.

Patients with hypertension frequently have vague complaints of dizziness and many other symptoms experienced by healthy individuals with motion sickness. We examined vestibular function in patients with essential hypertension, and we determined whether patients with essential hypertension are more prone to motion sickness using Coriolis stress testing. Vestibular function and Coriolis stress susceptibility were measured in 12 normotensive (NT) and seven asymptomatic patients with mild essential hypertension (HT). The Coriolis stress susceptibility index (CSSI) was calculated from the number of head movements in the four cardinal directions an individual could complete while being rotated in a computerized chair at increasing velocity before they developed motion sickness. The patients with hypertension had normal vestibular function and normal vestibuloocular responses as measured by standard techniques. Subjects with hypertension had significantly decreased Coriolis stress susceptibility scores compared to normotensive subjects (NT, 29.70 +/- 4.8; v HT, 5.48 +/- 2.0, P less than .001) and significantly decreased suppression of postrotatory nystagmus (NT, 44.5% +/- 3.8; v HT, 19.1% +/- 6.9, P less than .05). Medical treatment of hypertension did not result in an increased tolerance to provocative stimuli for motion sickness. It is suggested from our data that an increased susceptibility to motion sickness and abnormal vestibular responses to normal motion may account for many of the vague symptoms of "dizziness" reported by a large number of hypertensive patients.

Adult↗
PubMed2003

Vestibular-evoked myogenic potential in patients with unilateral vestibular neuritis: abnormal VEMP and its recovery.

The incidence of inferior vestibular nerve disorders in patients suffering from unilateral vestibular neuritis and the recovery of these disorders were evaluated by monitoring the vestibular-evoked myogenic potential (VEMP). Eight patients ranged from 21 to 73 years that suffered from unilateral vestibular neuritis underwent VEMP and caloric testing. Abnormal VEMP was observed in two of the eight patients with unilateral vestibular neuritis. Two patients were diagnosed as having an inferior vestibular nerve disorder. One of these patients showed recovery of the inferior vestibular nerve function as assessed by the VEMP. Disorders of the inferior vestibular nerve function and their recovery was confirmed by our current results. The time course of recoveries of the superior and inferior vestibular nerve systems were similar in the two patients.

Adult↗