Guangwei Zhou

Vestibular evoked myogenic potentials show altered tuning in patients with Ménière's disease.

Objective: Acoustic stimulation of the saccule gives rise to a vestibulocollic reflex, the output of which can be measured in the neck as inhibition of activity in the ipsilateral sternocleidomastoid muscle. This vestibular evoked myogenic potential has been promoted as a means of assessing integrity of saccular function. In this study, we test the hypothesis that the cochleosaccular hydrops of Ménière’s syndrome leads to alterations in saccular motion that change the dynamics of the vestibular evoked myogenic potential. Study Design: Prospective cohort study. Setting: Large specialty hospital, department of otolaryngology. Subjects: Fourteen normal adult volunteers and 34 consecutive consenting adult patients with unilateral Ménière’s disease by American Academy of Otolaryngology–Head and Neck Surgery diagnostic criteria. Interventions: All subjects underwent vestibular evoked myogenic potential testing using ipsilateral broadband click and short tone-burst stimuli at 250, 500, 1,000, 2,000, and 4,000 Hz. Main Outcome Measures: Threshold, amplitude, and latency of vestibular evoked myogenic potential responses in normal and Ménière’s affected and unaffected ears. Results: Vestibular evoked myogenic potential was present in all ears tested. Normal subjects show a frequency-dependent vestibular evoked myogenic potential threshold, with best response (“frequency tuning”) at 500 Hz. Compared with normal subjects and unaffected ears of Ménière’s subjects, affected Ménière’s ears had significantly increased vestibular evoked myogenic potential thresholds. Affected Ménière’s ears showed threshold shifts at all frequencies and there was less tuning apparent at 500 Hz. Unaffected ears of Ménière’s subjects also showed significantly elevated vestibular evoked myogenic potential thresholds compared with normal subjects. Analyses of vestibular evoked myogenic potential thresholds for effects of age, hearing loss, and audiometric configuration showed no significant differences. Conclusions: Ménière’s ears display alterations in vestibular evoked myogenic potential threshold and tuning, supporting our hypothesis of altered saccular motion mechanics arising from hydropic distention. Unaffected ears of unilateral Ménière’s subjects show similar changes, though to a lesser degree. This finding may be because of occult saccular hydrops in the asymptomatic ear or binaural interactions in the vestibular evoked myogenic potential otolith–cervical reflex arc.

Vestibular evoked myogenic potentials (VEMP) can detect asymptomatic saccular hydrops.

Objective: The objective of this study was to explore the useful of vestibular evoked myogenic potential (VEMP) testing for detecting endolymphatic hydrops, especially in the second ear of patients with unilateral Ménière disease (MD).

Vestibular evoked myogenic potential (VEMP) in patients with Ménière's disease with drop attacks.

Objective: In this retrospective study, we tested the hypothesis that vestibular evoked myogenic potential (VEMP) thresholds are more often elevated or absent in patients with Ménières disease experiencing Tumarkin drop attacks than in other patients with Ménières disease.

Vestibular evoked myogenic potentials versus vestibular test battery in patients with Meniere's disease.

Objective: The present study was undertaken to assess the sensitivity of vestibular evoked myogenic potentials testing to side-of-disease in Ménière’s disease patients and to test the hypothesis that information supplied by vestibular evoked myogenic potentials is complementary to that provided by a conventional vestibular test battery. Study Design: Prospective cohort study. Setting: Large specialty hospital, department of otolaryngology. Subjects: Twenty consenting adults (9 men and 11 women) with unilateral Ménière’s disease by American Academy of Otolaryngology–Head and Neck Surgery diagnostic criteria. Interventions: All subjects underwent bilateral vestibular evoked myogenic potentials testing using ipsilateral broadband click and short-toneburst stimuli at 250, 500, and 1,000 Hz. All subjects also underwent electronystagmography and sinusoidal vertical axis rotation testing. Main Outcome Measures: Accuracy of side-of-disease assignment by vestibular evoked myogenic potentials, caloric asymmetry, and multivariate analysis. Results: Side-of-disease assignment was most accurate using caloric asymmetry with a 5% interaural difference criterion, achieving 85% correct assignment. The next best method was vestibular evoked myogenic potentials using 250-Hz toneburst stimuli, achieving 80% correct assignment. The least accurate method was caloric asymmetry using a traditional 30% interaural difference limen, achieving 55% correct assignment. Comparison of 5% interaural difference criterion and vestibular evoked myogenic potentials using 250-Hz toneburst stimuli showed discordant results, but in no case did both 5% interaural difference criterion and vestibular evoked myogenic potentials using 250-Hz toneburst stimuli make an incorrect assignment. Conclusion: Vestibular evoked myogenic potentials threshold was shown to be highly sensitive to side-of-disease in unilateral Ménière’s disease. We observed instances of discordance in side-of-disease assignment by caloric asymmetry and vestibular evoked myogenic potential methods but no case in which both methods were incorrect. This supports the hypothesis that vestibular evoked myogenic potentials supplies information complementary to that provided by other components of the vestibular test battery.

Disturbance of vestibular function attributable to cochlear implantation in children

To investigate the prevalence and severity of vestibular impairment in children with cochlear implant (CI) and raise the awareness of vestibular disturbance following cochlear implantation.

Posterior semicircular canal dehiscence: first reported case series.

Objective: To identify clinical, audiological, and vestibular characteristics of posterior semicircular canal dehiscence. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: Twelve patients aged 2 to 67 years identified with posterior semicircular canal dehiscence. Interventions: Patients identified by suspicious clinical history and examination, confirmed by high-resolution computed tomography. Audiological evaluation included air and bone audiometry, tympanometry, acoustic reflexes, and vestibular evoked myogenic potential testing. Results: Hearing loss was mixed in 9 patients, conductive in 2 patients, and sensorineural in 1 patient, with downward-sloping configuration being the most common. Imaging revealed that 7 of 12 patients had dehiscence into a high-riding jugular bulb and 1 patient had an enlarged vestibular aqueduct with a Mondini malformation. One patient had Apert syndrome and another patient had microtia/atresia. Vestibular symptoms were more common in the adult patients than in the pediatric patients, with chronic disequilibrium the most common complaint. Vestibular evoked myogenic potential testing confirmed dehiscence with the characteristic response of reduced threshold and higher amplitude compared with healthy patients. Conclusion: This is the first reported series of adult and pediatric patients with symptomatic posterior semicircular canal dehiscence. Posterior semicircular canal dehiscence represents a third-window lesion manifesting as hearing loss with vestibular dysfunction. Computed tomography findings of a dehiscent posterior canal can be verified with increased vestibular evoked myogenic potential responses as in other third-window lesions. Patients found to have a high-riding jugular bulb and hearing loss should have specific inspection of the posterior canal to ensure it is not dehiscent.

Enlarged vestibular aqueduct: Review of controversial aspects†‡

To review the controversial aspects of the enlarged vestibular aqueduct syndrome.

Assessment of Saccular Function in Children With Sensorineural Hearing Loss

OBJECTIVE To investigate saccular function using vestibular evoked myogenic potentials in children with congenital or early acquired sensorineural hearing loss. DESIGN Retrospective cohort study. SETTING Pediatric tertiary referral center. PATIENTS Twenty-three children with bilateral sensorineural hearing loss (severe to profound in 22 cases, moderate in 1 case) underwent evaluation of saccular function. Twelve pediatric subjects with normal hearing were included in the study as the control group. INTERVENTIONS Otologic examination, computed tomography of the temporal bone, audiometry, tympanometry, and vestibular evoked myogenic potential testing. MAIN OUTCOME MEASURE Differences in threshold, amplitude, and P1 and N1 latencies of vestibular evoked myogenic potentials between children with normal-hearing and hearing-impaired children. RESULTS Abnormal vestibular evoked myogenic potentials were found in 21 of 23 children (91%) with sensorineural hearing loss. The thresholds of vestibular evoked myogenic potential were significantly higher (P <.001) and the amplitudes were lower in children with sensorineural hearing loss than those in children with normal hearing. There were no differences in the P1 and N1 latencies between the 2 groups. CONCLUSIONS The impairment of saccular function, indicated by the abnormal findings in the vestibular evoked myogenic potential, is often associated with sensorineural hearing loss in the pediatric population. Although saccular dysfunction may create a vestibular deficit, its manifestations can vary and be easily overlooked in children. Considering the high percentage of abnormal findings in our study, we recommend that deaf and hard-of-hearing children undergo vestibular evaluation. Vestibular evoked myogenic potential testing is an easy and reliable procedure to evaluate saccular function in children.

Delineating the hearing loss in children with enlarged vestibular aqueduct.

Objective/Hypothesis: To explore the clinical characteristics and audiologic outcomes in children with enlarged vestibular aqueduct (EVA).

Clinical experience in diagnosis and management of superior semicircular canal dehiscence in children.

To identify clinical characteristics of pediatric superior semicircular canal dehiscence (SSCD) and explore suitable options of management.