Vestibular Evoked Myogenic Potentials Latencies Research Articles

Otolithic functions in patients with residual dizziness after successful repositioning manoeuvres for unilateral posterior canal BPPV.

To evaluate otolithic functions in patients with residual dizziness after successful canalith repositioning procedures (CRPs) for unilateral posterior canal benign paroxysmal positional vertigo (BPPV), and to investigate possible risk factors. This case-control observational study included healthy controls and patients with residual dizziness after improvement following CRP for BPPV. All participants were subjected to full history taking, otoscopy, audiological basic evaluation, Dix-Hallpike test to search for posterior canal BPPV, residual dizziness screening, and vestibular evoked myogenic potential (VEMP) testing. Between-group differences were assessed and possible factors associated with residual dizziness were identified by univariate analysis. A total of 50 patients with residual dizziness (mean age, 56.53 ± 7.46 years [29 female: 21 male]) and 50 healthy controls (mean age, 58.13 ± 7.57 years [20 female: 30 male]) were included. A significant difference in VEMP latencies was found between the patient and control group (delayed in the patient group), with no significant between-group difference in amplitude in both ears. Aging, female sex, long duration of BPPV, number of CRPs, cervical VEMP and ocular VEMP abnormalities, and winter onset, were significantly associated with the risk of residual dizziness. Residual dizziness is a frequent sequel of BPPV that may relate to otolithic dysfunction. VEMP changes were revealed in the form of delayed latencies.

Clinical characteristics of vestibular evoked myogenic potentials in children with recurrent vertigo of childhood

ObjectiveTo explore the possible pathogenesis of recurrent vertigo of childhood (RVC) and the clinical diagnosis value of vestibular-evoked myogenic potentials (VEMPs). MethodsThe clinical data of 19 children (5.95 ± 0.38 years) diagnosed with RVC and 17 normal children (5.35 ± 0.31 years) enrolled in the control (NC) group from April 2017 to February 2021 was collected and analyzed. All subjects were tested for both cervical VEMP (cVEMP) and ocular VEMP (oVEMP). The elicit rate, thresholds, N1 latency, P1 latency, interval, amplitude, and amplitude asymmetry ratio (AAR) of VEMPs were compared and analyzed between the two groups. Results(1) The elicit rates of cVEMP and oVEMP have no significant difference between the two groups (P > 0.05). (2) The thresholds of cVEMP and oVEMP in the RVC group were higher than that in the NC group (P < 0.05). (3) The N1 latency of cVEMP in the RVC group was longer than that in the NC group (P < 0.05). The P1 latency of cVEMP and latencies of oVEMP have no significant difference between the two groups (P > 0.05). (4) The interval of cVEMP in the RVC group was longer than that in the NC group (P < 0.05), while the interval of oVEMP has no significant difference between the two groups (P > 0.05). (5) The amplitude of cVEMP in the RVC group was higher than that in the NC group (P < 0.05), while the amplitude of oVEMP was similar in the two groups (P > 0.05). (6) The AAR values of oVEMP and cVEMP were similar in the two groups (P > 0.05). ConclusionsThe elicit rates of VEMPs in children with RVC did not differ from that of normal children, but the thresholds were all increased, suggesting reduced sensitivity of the otolith organ and vestibular nerve conduction pathways. The P1 latency of cVEMP was normal in children with RVC, but N1 latency and interval of cVEMP were increased, we finally reached a conclusion that there might be potential impairment in the inferior vestibular nerve and the subsequent nerve conduction pathway in RVC.

Effect of Electrode Montage on 500-Hz Tone Burst Evoked Masseter Vestibular Evoked Myogenic Potential.

Masseter vestibular evoked myogenic potentials (VEMPs) are short-latency myogenic responses obtained in response to electric or acoustic stimulation. It is a relatively newer test that helps assess the vestibulo-trigeminal pathway, thereby gaining more interest in brainstem pathologies like Parkinsonism, multiple sclerosis, and idiopathic random eye movement disorders. The purpose of the study was to compare the effect of zygomatic versus mandibular reference montage on the latency and amplitude of masseter VEMP (mVEMP) using a 500-Hz tone burst stimulus. Twenty healthy participants in the age range of 18-29 years, with no complaints of vestibular signs and symptoms, were recruited for the study. VEMP was recorded for all the participants using 500-Hz tone burst stimuli in zygomatic electrode montage and mandibular electrode montage. mVEMP was recorded in both ipsilateral and contralateral modes. The Wilcoxon signed-ranks test revealed no significant difference between the zygomatic and mandibular montage for both the latency and amplitude parameters (p > .05). This study revealed no significant difference in p11 and n21 latencies as well as p11-n21 rectified amplitude between zygomatic and mandibular montage using a 500-Hz tone burst stimulus in young adults. Hence, utilizing a 500-Hz tone burst, mVEMP can be recorded in zygomatic and mandibular electrode montage.

Audiovestibular Dysfunction in Siblings with Charcot-Marie-Tooth Disease 4F: A Case Series.

Charcot-Marie-Tooth disease type 4F (CMT4F) is an autosomal recessive disorder with symptoms presenting in early adulthood. This clinical case series demonstrates atypical findings in cervical and ocular vestibular evoked myogenic potentials (VEMP) in siblings with CMT4F. The aim of this study was to highlight the audiovestibular test findings in CMT4F. Case series study sample: 4 siblings, 3 of whom diagnosed with CMT4F. Audiological test battery and electrophysiological tests comprising auditory brainstem response (ABR) and VEMP (both cervical and ocular) were performed in our patient population. Older siblings, in whom the hearing loss was present, manifested prolonged peak V latencies in ABR. Three out of four siblings with CMT4F showed prolongation of latencies on cervical and ocular VEMP. In many neurodegenerative conditions, prolongation of ABR peak latencies has often been reported in the literature. There have also been a few reports of prolonged VEMP peak latencies. This article reports prolongation of only VEMP peak latencies (in both cervical and ocular recordings). The youngest sibling had prolongation of VEMP latencies, with ABR peak latencies being normal. The assumption we put forth that CMT4F may affect the vestibular pathway first requires to be tested on a larger sample and by longitudinally studying the individuals with disease condition.

Ocular and cervical vestibular evoked myogenic potentials elicited by air-conducted, low-frequency sound.

Sound is not only detected by the cochlea, but also, at high intensities, by the vestibular system. Acoustic activation of the vestibular system can manifest itself in vestibular evoked myogenic potentials (VEMPs). In a clinical setting, VEMPs are usually evoked with rather high-frequency sound (500 Hz and higher), despite the fact that only a fraction of saccular and utricular hair cells in the striolar region is available for high-frequency stimulation. As a growing proportion of the population complains about low-frequency environmental noise, including reports on vestibular symptoms, the activation of the vestibular system by low-frequency sound deserves better understanding. We recorded growth functions of oVEMPs and cVEMPs evoked with air-conducted sound at 120 Hz and below. We estimated VEMP thresholds and tested whether phase changes of the stimulus carrier result in changes of VEMP amplitude and latency. The VEMP response of the otholith organs to low-frequency sound is uniform and not tuned when corrected for middle ear attenuation by A-weighting the stimulus level. Different stimulus carrier phases result in phase-correlated changes of cVEMP latencies and amplitudes. VEMPs can be evoked with rather low-frequency sound, but high thresholds suggest that they are unlikely to be triggered by environmental sounds.

Predictive Value of Vestibular Evoked Myogenic Potentials in the Diagnosis of Menière's Disease and Vestibular Migraine.

To explore the usefulness of vestibular evoked myogenic potentials (VEMPs) in the diagnosis of Menière's disease (MD) and vestibular migraine (VM). Retrospective cohort. Multidisciplinary neurotology clinic. Definite MD and definite VM patients between January, 2015 and May, 2017, as well as healthy volunteers. Cervical and ocular VEMP (cVEMP and oVEMP) testing. VEMP response, amplitude, and latency. Twenty five definite MD, 34 definite VM, and 13 control subjects were analyzed. MD affected ears had significantly lower cVEMP (p = 0.007) and oVEMP (p < 0.001) amplitudes than control ears. VM ears had significantly lower oVEMP (p = 0.001), but not cVEMP (p = 0.198) amplitudes than control ears. MD affected ears, but not VM ears, had significantly more absent cVEMP (25.9% versus 0%, p = 0.005) and oVEMP responses (40.7% versus 0%, p < 0.001) than control ears. oVEMP latency was significantly shorter for both MD affected (p < 0.001) and VM ears (p < 0.001) than control ears. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated using a neurotology clinic MD prevalence of 7.9% in dizzy patients. A present cVEMP or oVEMP both have more than 93% chance of ruling MD out in the tested ear, while a cVEMP amplitude more than 54.9 μV or oVEMP amplitude more than 5.1 μV both have more than 94% of ruling out MD in the tested ear. Despite some overlap in VEMP results between MD and VM, when the diagnosis is uncertain between the two disorders due to symptomatic overlap and nonspecific audiometric data, VEMPs can be helpful in guiding treatment toward one disease entity or the other until more evidence points to a definitive diagnosis.

Assessment of cervical and ocular vestibular evoked myogenic potentials in multiple sclerosis(MS) patients

Multiple sclerosis (MS) is one of the most important chronic neurological disease affecting the central nervous system and is the leading cause of disability due to brainstem affiction. Vestibular evoked myogenic potentials (VEMPs) are short-latency muscle responses. Cervical VEMP (Cvemp) is a demonstration of vestibule-collic reflex, while ocular VEMP (oVEMP) which is a manifestation of vestibulo–ocular reflexes. The aim of this study was to assess cVEMP and oVEMP in MS patients with and without brainstem lesion(s) and comparing the findings with normal controls. Both latency and amplitude of cVEMP (p13-n23) and oVEMP (n10-p15) were recorded in10 healthy matched controls, 10 MS patients with BS lesion(s)and 10 MS patients without BS lesion(s). All patients underwent a complete audiological examination, clinical neurological evaluation and brain MRI scanning. The latency of P13-N23 and N10-P15 in MS participants with and without BS lesions were significantly prolonged compared to normal controls (p ≤ 0/05). Additionally latency of P13-N23 and N10-P15 in patients of MS with BS lesion(s) were significantly prolonged compared to patients without BS lesion(s) (p ≤ 0.05). No relationship was found between the clinical state and VEMP responses. No relationship was found between the radiological findings of the patient and VEMP responses except for the group of MS with BS affection. A good correlation was found between VEMP latencies and EDSS. Abnormality of cervical VEMP and ocular VEMP in patients of Multiple Sclerosis with brainstem lesion(s) are more frequent than in patients of Multiple Sclerosis without brainstem lesion(s) .

92. Myogenic vestibular-evoked potentials: An extension of the assessment protocol

Vestibular-Evoked-Myogenic-Potentials (VEMPs) represent a muscular response following an intense acoustic stimulation. The cVEMPs explore a reflex arc (from saccule to the neck musculature) and usually are only recorded from sternocleidomastoideus (SCM). 1 They are non-invasive, well-tolerated, simple-to-perform and very useful in several diseases. The normal response is a biphasic complex P13/N23. We propose a more extensive protocol. We recruited 31 subjects (mean age ± SD:50.8 ± 19.0). VEMPs were recorded symmetrically and simultaneously through surface electromyography from SCM, splenius (SPL), trapezius (TRP) and orbicularis oculi (OO). The sensitivity was 20 μ V, band pass filter 20–2000 Hz, tone acoustic stimulus was monaural and binaural at 500 Hz, rate at 5.3 Hz. Three runs of 150 sweeps were averaged. The patients remained in clinostatic position with anterior neck flexion. Like the SCM cVEMP, the SPL and TRP cVEMP was characterized by a biphasic wave of muscle activity that began at ∼13 ms. Responses were consistent and repeatable. VEMPs latencies and amplitude showed a higher inter-reliability for the four muscles. The protocol offer a complementary target for cVEMP assessments. The simultaneous recording of oVEMPs and cVEMPs provide the evaluation of the ascending and descending vestibular pathways, allowing an extensive overview of brainstem function.

Degeneration of the vestibular nerve in unilateral Meniere's disease evaluated by galvanic vestibular-evoked myogenic potentials.

The staging system of Meniere's disease utilizes audiograms to probe cochlear dysfunction. We explored the addition of galvanic vestibular-evoked myogenic potentials (VEMP) to further explore vestibular function. Seventy patients with unilateral Meniere's disease were enrolled in this study. Within 2weeks of diagnosis, all subjects underwent pure tone audiometry, cervical and ocular VEMP, and caloric test. The prevalence of abnormal tests and the VEMP characteristic parameters such as latencies and amplitudes were analyzed. In affected ears, the abnormal rate of acoustic cVEMPs, galvanic cVEMPs, vibratory oVEMPs and galvanic oVEMPs was 37%, 17%, 20%, and 9%, respectively. No significant differences existed in VEMP latencies and amplitudes between affected ears and unaffected ears. The impairment of otolithic organs was found to be more than that of vestibular afferents. The deterioration of the saccule was more than that of the utricle, whereas retrolabyrinthine degeneration of sacculo-collic reflex and vestibulo-ocular reflex was similar. This study is the first to use an electrophysiological test to evaluate the retrolabyrinthine function of patients with unilateral Meniere's disease.

EP 140. Vestibular evoked myogenic potentials: A retrospective analysis

Diagnostic testing of the vestibular system is an integral part of assessment of patients with balance dysfunction. Rediscovery of Vestibular Evoked Myogenic Potentials (VEMP) has introduced a new dimension to vestibular assessment, especially otolith function. We present a retrospective analysis of both C-VEMP and O-VEMP in neurologic & otologic conditions. Data collated retrospectively from records of 98 patients referred for diagnostic VEMP testing to the Electrophysiology laboratory. Presenting symptoms were imbalance and giddiness. 45 male and 53 female patients in the age range of 17–79 years. 38 had Benign Paroxysmal Positional Vertigo (BPPV), 12 Acute Vestibular Neuronitis, 11 Meniere’s Disease, 7 Chronic Otitis Media ( 3 right, 2 left and 2 bilateral ). 1 was referred to confirm left Superior Canalicular Dehiscence, 9 Parkinson Disease, 1 ProgressiveSupranuclearPalsy and 4 Multiple Sclerosis. 15 remained unclassifiable and were categorised as Vertigo Not Otherwise Specified (NOS). Cervical and Ocular VEMP were performed on both ears on all the patients with Medicaid EP machine. Testing done in one session lasting about 30 minutes for each patient. Rest periods given between sets to prevent muscle fatigue. Cervical VEMP: active recording electrodes on Sternocleidomastoid belly ipsilateral to auditory stimuli. Reference on the manubrium sterni. Patients instructed to raise the head about 30 degrees above the bed and hold it actively at that level . Ocular VEMP: recording electrodes were placed contralaterally, active 1 cm inferior to lower eyelid and reference, 2 cm below that. Maximum upgaze was encouraged during testing. Ground electrode: forehead for both tests. Stimulation Parameters: Rarefaction clicks: 100 microsec duration, 5 Hz frequency , intensity 120–125 dB nHL, headphones. Recording Parameters: Filters: Low frequency filter- 20 Hz, High frequency filter- 3 KHz. Sweep: 10 msec/divn. Total sweep of 100 msec. Gain: 100 microvolts /divn. Notch: None. Averages: 100/set, 2 sets for each test. Parameters analysed : Latencies of P13, N23 and amplitude of cervical VEMP on both sides. Latencies of N10, P16 and amplitude of ocular VEMP on both sides. Comparison against normative values and two tailed t test with unequal variance were performed to look for statistically significant deviation in each subgroup of diseases. There was no statistically significant difference in latencies and amplitudes of cervical (p = 0.39 and 0.28 for left and right respectively ) and ocular VEMP (p = 0.4 and 0.64 for left and right respectively) in BPPV. In some patients with Acute Vestibular Neuronitis cervical and ocular responses were absent. Very significant difference in latencies and amplitudes (p < 0.01 on left, p < 0.001 bilaterally) were noted. In Meniere’s disease, p values < 0.01 were obtained uniformly for both cervical and ocular VEMP. p < 0.001 for cervical and ocular VEMP in Otitis Media except the left ocular VEMP which trended the disease. PD and PSP group showed statistically significant differences in cervical and ocular VEMP latencies and amplitudes (p < 0.01). Number of patients with Multiple Sclerosis is small and the results are inconclusive. In the sole patient with left Superior canal dehiscence, the cervical and ocular VEMP were larger than normal ( more than twice in amplitude as against average for the age) on the left thus underscoring its use in this condition. 15 patients had imbalance and giddiness, but not diagnosed with a CNS, PNS or vestibular disorder. Interestingly the Cervical VEMP was significantly abnormal (p < 0.001) but the Ocular VEMP did not show statistically significant deviation in latency or amplitude. This suggests a dichotomy between saccular & utricular pathology, the former being responsible for the patients symptoms. This is, to the best of our knowledge the first report of abnormalities of both Cervical and Ocular VEMP in patients with neurologic and neurootologic disorders from India. The role of VEMPs in studying degenerative neurological disorders (PD and PSP) with imbalance and falls has been explored and since abnormalities in both cervical and ocular VEMPs are noted,suggesting a role for the vestibular system and central connections in imbalance & loss of posture in these conditions. Role of VEMP in MS is routinely mentioned, but it is at best an adjunct diagnostic procedure. The lack of usefulness of VEMP in BPPV has been underscored by this study. But it may be useful in acute attacks of Meniere’s disease and Acute Vestibular Neuronitis to guage the extent and laterality of damage, especially since these disorders are bilateral.Our findings suggest that Ocular VEMP is more sensitive than Cervical VEMP in Vestibular Neuronitis. In chronic otitis media VEMPs are abnormal and can be useful to evaluate integrity of labyrinthine function. The main drawback is the paucity of numbers in different categories. Based on these findings we propose to enrol more patients, especially in the neurological subsets prospectively to elucidate the role of VEMP.

Ocular and Cervical Vestibular Evoked Myogenic Potentials (VEMPs) in healthy volunteers: the intra-, interobserver, and the test re-test reliability.

The aims of the study are to determine the intra-, interobserver, and the test re-test reliability of the cervical and ocular vestibular evoked myogenic potentials (VEMPs). Twenty healthy subjects underwent acoustically and forehead tap elicited cervical and ocular VEMPs. The measurements were repeated one week later. The intra- and interobserver reliability of both ocular and cervical VEMPs is excellent. The test re-test reliability of the raw p13n23 peak-to-peak amplitudes of the cervical VEMPs is excellent (ICC: 0.76, 0.87) and the p13 latencies show a good reliability (ICC: 0.56, 0.73). The raw n1p1 peak-to-peak amplitudes of the ocular VEMPs show a fair-to-good test re-test reliability (ICC: 0.51, 0.64) and the n1 and p1 latencies show a poor reliability (ICC: -0.17 ≤ x ≤ 0.44). The intra- and interobserver reliability of the cervical and ocular VEMPs is excellent. The raw ocular and cervical VEMP peak-to-peak amplitudes are the most reliable parameters, followed by the cervical VEMP latencies. The ocular VEMP latencies shows a poor test re-test reliability. The individual VEMP results, however, remained within normal limits despite the test re-test variability.

Association between saccular function and gait speed: data from the Baltimore Longitudinal Study of Aging.

To investigate whether otolith function (saccular and utricular) is associated with walking performance. Cross-sectional analysis of observational data collected in the Baltimore Longitudinal Study of Aging. National Institute on Aging Intramural Research Program Clinical Research Unit at Harbor Hospital, Baltimore, Maryland. Community-dwelling participants. Cervical and ocular vestibular evoked myogenic potentials (VEMPs) were used to assess saccular and utricular function, respectively. Cervical and ocular VEMP latency and amplitude responses and usual, rapid, and narrow (20 cm) gait speed assessed over a 6-m course. In 314 participants (mean age, 73.1 yr; range, 26-96 yr), cervical VEMP amplitude mediated the association between age and gait speed-particularly narrow walk speed-in both men and women. Cervical VEMP latency had an independent association with gait speed in age-, height-, and weight-adjusted analyses, although the direction of the association differed by sex. Greater cervical VEMP latency was associated with slower usual, rapid, and narrow gait speed in women but faster rapid gait speed in men. Neither the amplitude nor latency of ocular VEMP was associated with gait speed in men or women. These findings suggest that age-related slowing of gait speed is in part mediated by the decreased magnitude of saccular response associated with age. The sex-related differential association between saccular response latency and gait speed requires further study.

On the impact of examiners on latencies and amplitudes in cervical and ocular vestibular-evoked myogenic potentials evaluated over a large sample (N = 1,038).

Vestibular-evoked myogenic potentials (VEMPs) are frequently used in the clinical diagnosis and research of vertigo syndromes. Altered latencies or amplitudes are typically interpreted as an indication of disturbance in the processing of vestibular stimuli along the otolithic pathways. Correct interpretation, however, can be difficult as VEMP amplitudes can vary greatly across subjects and across laboratories, likely because they are very sensitive to measurement conditions. Here, we attempted to quantify the impact of examiner differences on VEMP data. We collected data from 1,038 people using eight different experimental examiners, and investigated the effect of examiner on VEMP latencies and amplitudes. We found that the examiner collecting the data had a strong effect on outcome measures with significant differences (p < 0.001) in cVEMP and oVEMP latencies and in oVEMP amplitudes. No significant differences between examiners were found for the cVEMP amplitudes. When we compared the healthy and pathological sides of patients with a clinically diagnosed unilateral disease, no significant differences between sides were found. Given our results and the results reported in the literature, we conclude that the signal features of VEMPs are very sensitive to variables that may be influenced by the examiner. The field should therefore work on a better standard for VEMP recordings.

Epidemiology of vestibular evoked myogenic potentials: Data from the Baltimore Longitudinal Study of Aging

ObjectiveTo evaluate whether age-related changes in vestibular evoked myogenic potentials (VEMPs) differ by demographic and cardiovascular risk groups. MethodsParticipants in the Baltimore Longitudinal Study of Aging underwent cervical and ocular VEMP testing. VEMP latency, amplitude, asymmetry ratios, and prevalence of absent responses were compared across demographic and cardiovascular risk groups. ResultsIn 257 participants (mean age 72.9, 57% female), ocular VEMP (oVEMP) n10 latency increased by 0.12ms/decade while amplitude decreased by 2.9μV/decade. Black participants had better oVEMP function (shorter latency, increased amplitude, and decreased odds of absent responses) relative to white participants. In 250 participants (mean age 72.6, 54% female), EMG-corrected cervical VEMP (cVEMP) amplitude decreased by 0.14μV/decade and p13 latency was 0.38ms longer in males. The odds of absent responses were significantly higher in individuals age ⩾80 for oVEMPs, and age ⩾70 for cVEMPs. Cardiovascular risk factors had no association with VEMP parameters. ConclusionsWe confirmed age-related declines in otolith function, and observed a protective effect of black race on oVEMP latency and amplitude. SignificanceThese results illustrate how measures of otolith function change with age in community-dwelling adults. Further investigations are needed to ascertain whether better otolith function in blacks might contribute to a lower risk of mobility disability and falls.

The Clinical Utility of Vestibular Evoked Myogenic Potentials in Patients of Benign Paroxysmal Positional Vertigo.

Vestibular Evoked Myogenic Potentials (VEMP) is an emerging tool to diagnose Benign Paroxysmal Positional Vertigo (BPPV). The clinical utility of VEMP has been reported only in small accord in Indian literature. To study the latency and amplitude of VEMP in patients with BPPV and compare it with that of normal subjects. The study included two groups. Group one (control group) were 18 normal subjects. Group two (test group) were 15 subjects with unilateral BPPV. Those subjects who fulfilled the selection criteria based on case history and audiological assessment were taken for the VEMP recording. The VEMP response consist of positive and negative successive waves (pI-nI), with latency values in adults about 13 and 23 milliseconds respectively. Data was analysed using Statistical Package for Social Sciences (SPSS) version 12 (Chicago, IL, USA). Unpaired t-test was employed to measure the statistical difference between control group and test group. The difference in n23 and the peak to peak amplitude between the ipsilateral and contralateral ears of the test group were statistically significant, whereas such a difference in the p13 latency turned out to be statistically insignificant. It should be noted that, out of 15 patients in the test group, five patients showed only artifact tracer recordings in both the ears which is considered as no response. The heterogeneity of the results extended from absence of VEMP to prolongation of both p13, n23; prolongation of p13 alone; and even side to side variations. Absent response from the ipsilateral ear, prolonged latency of n23 and decreased peak to peak amplitude (p13, n23), indicates the disease pathology. However, large sample size is required to draw further conclusions and to consolidate the usage of VEMP in the diagnosis of BPPV.

Evaluation of dizzy adult patients using the Arabic dizziness questionnaire and its correlation with different vestibular test results

Objectives The aim of this study was to develop an Arabic dizziness questionnaire for adults and compare the questionnaire conclusion with the results of vestibular evaluation. Participants and methods Twenty dizzy adults, age 21-60 years, were subjected to an interview with patients using the Arabic dizziness questionnaire, otological examination, bedside examination for dizzy patients, basic audiological evaluation, and vestibular assessment, which included the following: videonystagmography, cervical vestibular-evoked myogenic potentials, and sensory organization testing through dynamic posturography. Parameters under study were questionnaire scores and conclusion, videonystagmography results including canal paresis, and cervical vestibular-evoked myogenic potentials latency, amplitude, and threshold. Sensory organization testing result analysis in the form of equilibrium scores and sensory analysis. Results Comparisons and correlations between the vestibular score of the questionnaire and results of the vestibular assessment were nonstatistically significant. The most common diagnoses for dizziness in the adult group were vestibular neuritis (four cases), Mιniθre's disease (four cases), benign paroxysmal positional vertigo (three cases), and migraine-associated dizziness (three cases). Conclusion Adult patients sharing the same diagnosis consistently answered certain questions positively in the questionnaire. We recommend the use of the dizziness questionnaire as a first step of the test battery for the evaluation of dizzy patients.

Efficacy of L‐N‐Acetyl Cysteine in the Prevention of Gentamicin Vestibulotoxicity in Rats

Objectives: Determine the effect of L-N-acetylcysteine (LNAC) on gentamicin (GM) initiated vestibulotoxicity. Methods: Wistar rats were divided into 4 groups: Group A (n = 7) had intratympanic (IT) GM (20 mg in 40 µL); group B (n = 6) had IT GM and intraperitoneal (IP) LNAC (350 mg/kg) at 24 hours and 1 hour before GM administration; group C (n = 6) had IT GM and IT LNAC (5 mg in 40 µL); and group D (n = 6) had only IT saline (40 µL). Rats were tested by ABR and cervical vestibular evoked myogenic potentials (VEMP) pretreatment, and at 1 week and 1 month posttreatment. Morphological analysis of the inner ears was performed at 1 month. Main outcome measures were the mean change in VEMP P1 latency at sound stimulation from 80 to 110 dB SPL, and hair cell count in the saccule. Results: Rats treated with IT LNAC exhibited the least change in mean VEMP latencies, although the intergroup differences were not statistically significant except for 80 dB stimulation at 1 week posttreatment. IP and IT LNAC resulted in preservation of the VEMP response in all rats, whereas 42% of rats not receiving LNAC had absent responses. Morphological analysis of the saccule revealed lower mean hair cell counts in rats not receiving LNAC. Conclusions: Systemic and IT administration of LNAC of rats treated with GM resulted in minimal variations in VEMP latencies and greater preservation of vestibular hair cells. The protective effect of LNAC in GM-initiated vestibulotoxicity is promising and warrants further research.

Particularité du test calorique chez le jeune enfant

To explore the possible pathogenesis of recurrent vertigo of childhood (RVC) and the clinical diagnosis value of vestibular-evoked myogenic potentials (VEMPs).The clinical data of 19 children (5.95 ± 0.38 years) diagnosed with RVC and 17 normal children (5.35 ± 0.31 years) enrolled in the control (NC) group from April 2017 to February 2021 was collected and analyzed. All subjects were tested for both cervical VEMP (cVEMP) and ocular VEMP (oVEMP). The elicit rate, thresholds, N1 latency, P1 latency, interval, amplitude, and amplitude asymmetry ratio (AAR) of VEMPs were compared and analyzed between the two groups.(1) The elicit rates of cVEMP and oVEMP have no significant difference between the two groups (P > 0.05). (2) The thresholds of cVEMP and oVEMP in the RVC group were higher than that in the NC group (P < 0.05). (3) The N1 latency of cVEMP in the RVC group was longer than that in the NC group (P < 0.05). The P1 latency of cVEMP and latencies of oVEMP have no significant difference between the two groups (P > 0.05). (4) The interval of cVEMP in the RVC group was longer than that in the NC group (P < 0.05), while the interval of oVEMP has no significant difference between the two groups (P > 0.05). (5) The amplitude of cVEMP in the RVC group was higher than that in the NC group (P < 0.05), while the amplitude of oVEMP was similar in the two groups (P > 0.05). (6) The AAR values of oVEMP and cVEMP were similar in the two groups (P > 0.05).The elicit rates of VEMPs in children with RVC did not differ from that of normal children, but the thresholds were all increased, suggesting reduced sensitivity of the otolith organ and vestibular nerve conduction pathways. The P1 latency of cVEMP was normal in children with RVC, but N1 latency and interval of cVEMP were increased, we finally reached a conclusion that there might be potential impairment in the inferior vestibular nerve and the subsequent nerve conduction pathway in RVC.

Otolith Dysfunction as a Possible Cause for the Development of Idiopathic Scoliosis

To investigate whether otolith system, as a major contributor to muscles for postural control, might play a role in the pathogenesis of idiopathic scoliosis (IS). Cervical vestibular-evoked myogenic potentials (VEMP) testing was applied to investigate the otolith function in patients with IS. Twenty-nine healthy patients (mean age 13.5±2.5 y, 4 males) were included. In all but 2 patients, the major curve deviation was to the right and the mean angle deviation was 49.7±21.6 degrees. Nineteen age-matched individuals (10 males) served as controls. The P13 (first positive wave) latencies were comparable in both groups. Patients with IS had significantly longer N23 (first negative wave) latencies than controls. A high correlation between the age and N23 latencies on the right was found in IS patients. A link between the scoliosis angle and VEMP latencies could not be demonstrated.The VEMP amplitudes were higher in patients than in controls, whereas the amplitude asymmetry ratio was similar in both groups. This work brings further evidence for vestibular abnormalities in patients with IS. Prospective studies are needed to elucidate a possible causative relationship between otolith dysfunction and the development of scoliosis. III.

Vestibular evoked myogenic potentials in term newborn infants with severe hyperbilirubinemia

The aim of this study was to determine the effects of severe hyperbilirubinemia on vestibular evoked myogenic potentials (VEMP). A prospective study was designed. Seventeen term infants who suffered from severe hyperbilirubinemia in the first 5 postnatal days of age were included in the study group. The control group consisted of 17 healthy term infants. Audiological evaluation was performed, including tympanometry and transient evoked otoacoustic emissions, and VEMP tests. All newborns passed audiological evaluation. Biphasic waveforms of VEMP were obtained in all of the 34 infants who had been tested. Both latencies of p13 and n23 were significantly delayed in the severe hyperbilirubinemia group (P < 0.05). This pilot is the first study to show that severe hyperbilirubinemia causes delay in VEMP latencies. We suggest that severe hyperbilirubinemia might affect the vestibular nuclei or the integrity of the inferior vestibular nerve and vestibulospinal tract. Further studies need to explain the relation between hyperbilirubinemia and the vestibular system.