Vestibular Evoked Myogenic Potentials Recording Research Articles

Practical instructions for recording vestibular evoked myogenic potentials

Recording of vestibular evoked myogenic potentials (VEMPs) is awell-established method for functional diagnostics of the otolith organs. VEMPs are vestibular reflexes of the sacculus und utriculus to acoustic stimulation by air-conducted sound or bone-conducted vibration and are recorded by surface electrodes from the cervical (cVEMP) and ocular (oVEMP) muscles. The results of VEMP recordings are part of the neuro-otologic test battery and enable diagnosis of various vestibular disorders or differentiation between non-vestibular and peripheral vestibular vertigo. However, the methods for recording VEMPs vary substantially, although recording and stimulation parameters as well as methods of data analysis have asignificant influence on the results. This article provides an overview of recommended parameters as well as practical instructions for the recording, analysis, and interpretation of VEMPs.

Vestibular evoked myogenic potential (VEMP) test-retest reliability in adults.

The technique of measuring ocular vestibular evoked myogenic potentials (oVEMP) in response to Mini-shaker vibration is relatively new, there is a limited normative data to define the presence or absence of a response in the literature. To determine the test-retest reliability of cervical and ocular VEMPs (cVEMP and oVEMP, respectively) to air-conducted sound (ACS) and bone-conducted vibration (BCV) stimulation and to determine normative ranges for the responses. Twenty normal-hearing individuals (40 ears) and 20 hearing impaired volunteers with normal balance function (40 ears) were examined in this study. ACS cVEMP and BCV oVEMP (using a Mini-shaker) were recorded from both groups to assess the test-retest reliability and to collect normative VEMP data for P1/N1 latencies and amplitudes from 20 normal hearing individuals. To test reliability, VEMP recordings were repeated within the same session. The test-retest reliability for all the cVEMP parameters showed excellent reliability whereas oVEMP parameters showed between fair and excellent reliability depending on the parameter tested. Normative data for VEMP P1/N1 latencies and amplitudes were established. Normative data and test-retest reliability for BCV oVEMP using the Mini-shaker at 100 Hz were established in our study for the first time in the literature. Responses appear reliable.

Magnitude, variability and symmetry in head acceleration and jerk and their relationship to cervical and ocular vestibular evoked myogenic potentials.

Acceleration and changes in acceleration (jerk) stimulate vestibular otolith afferents. Bone-conducted (BC) vibration applied to the skull accelerates the head and produces short latency reflexes termed vestibular evoked myogenic potentials (VEMPs). To determine the magnitude, variability and symmetry in head acceleration/jerk during VEMP recordings and investigate the relationship between head acceleration/jerk and VEMP properties. 3D head accelerometery (sagittal, interaural and vertical axes) was recorded bilaterally in thirty-two healthy subjects during cervical (cVEMP) and ocular (oVEMP) recordings. BC 500 Hz sinusoidal tones were applied to the midline forehead using a positive polarity stimulus. The direction of induced acceleration/jerk was predominately backward, outward and downward on either side of the head during cVEMP and oVEMP recordings.Overall, acceleration/jerk was larger in the sagittal and interaural axes and peaked earlier in the interaural axis bilaterally. Acceleration was more symmetric in the sagittal and interaural axes whereas jerk symmetry did not differ between axes. Regression models did not show a systematic relationship between acceleration/jerk and either VEMP reflex. The pattern of skull acceleration/jerk was relatively consistent between the two sides of the head and across subjects, but there were differences in magnitude, leading to inter-side and inter-subject variability.

Abnormal vestibular brainstem structure and function in an animal model of autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that includes several key neuropathological changes and behavioral impairments. In utero exposure to the anti-epileptic valproic acid (VPA) increases risk of an ASD diagnosis in human subjects and timed in utero exposure to VPA is a clinically relevant animal model of ASD. Many human subjects with ASD have cerebellar hypoplasia, fewer Purkinje cells, difficulties with balance, ophthalmic dysfunction and abnormal responses to vestibular stimulation and such vestibular difficulties are likely under reported in ASD. We have recently shown that animals exposed to VPA in utero have fewer neurons in their auditory brainstem, reduced axonal projections to the auditory midbrain and thalamus, reduced expression of the calcium binding protein calbindin (CB) in the brainstem and cerebellum, smaller and occasionally ectopic cerebellar Purkinje cells and ataxia on several motor tasks. Based on these findings, we hypothesized that in utero VPA exposure similarly impacts structure and function of the vestibular brainstem. We investigated this hypothesis using quantitative morphometric analyses, immunohistochemistry for CB, a battery of vestibular challenges, recording of vestibular-evoked myogenic potentials and spontaneous eye movements. Our results indicate that VPA exposure results in fewer neurons in the vestibular nuclei, fewer CB-positive puncta, difficulty on certain motor tasks, longer latency VEMPs and significantly more horizontal eye movements. These findings indicate that the vestibular nuclei are impacted by in utero VPA exposure and provide a basis for further study of vestibular circuits in human cases of ASD.

Response characteristics of vestibular evoked myogenic potentials recorded over splenius capitis in young adults and adolescents

Background and objectivesExamine vestibular evoked myogenic potential (VEMP) responses recorded from surface electrodes over Splenius Capitis (SPC) in a seated position. Specific aims: (1) validate response characteristics of VEMP recordings from surface electrodes over Sternocleidomastoid (SCM) and over SCP and (2) assess age effects on responses in adolescents and young adults. Materials and methodsSimultaneous surface VEMP was recorded bilaterally from electrodes placed over the dorsal neck musculature at a location known from previous work to record from SPC in 15 healthy participants during trials with head rotation toward and away from the stimulated ear. VEMP was also recorded from electrodes over SCM, ipsilateral to the stimulus ear, in the same participants in a supine, head lift/turn position. ResultsResponse amplitudes significantly increased with contraction strength and decreased with age. Participants were able to maintain sufficient contraction strength (amplitude) with head rotation to reliably measure over SPC. Normalized response amplitudes measured from electrodes over contralateral SPC were largest with head rotation contralateral to the stimulus ear. Normalized amplitudes and peak latencies were comparable to the same measures from SCM obtained in supine, head lift/turn position. ConclusionsOtolith generated myogenic responses can be recorded seated from electrodes over the dorsal neck with head rotation contralateral to the stimulus ear. In this position, contralateral recordings are consistent with responses known from previous work to arise from SPC; ipsilateral recordings may include crosstalk from activated muscles nearby, including ipsilateral SCM. Overall, techniques targeting contralateral SPC during contralateral head turn may provide additional methods of recording VEMPs.

A study of vestibular evoked myogenic potential and clinical features in benign paroxysmal positional vertigo: An institutional experience

Background: Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder in adults caused by degeneration of the otolithic organs in most cases but may also be a consequence of head injury, labyrinthitis, and ischemia in the distribution of the anterior vestibular artery or prolonged bed rest. The aim of the study is to find the correlation of alterations in vestibular evoked myogenic potential (VEMP) recordings in BPPV patients, with other associated symptoms. Materials and Methods: The study was conducted in 29 BPPV patients over a 3-year period. All patients were investigated with pure-tone audiometry, bithermal caloric test with Electronystagmography (ENG) recording, and VEMP recording. Clinical tests included Romberg, Sharpened Romberg, and Dix–Hallpike tests. Associated parameters were recorded, and any association with abnormal VEMP was evaluated. Results: VEMP was abnormal in three patients. There was no association of abnormal p or n latency with BPPV. No significant relationship with any clinical parameter was observed. Conclusions: BPPV is associated with the occurrence of abnormal VEMP recordings, possibly due to degeneration of the saccular macula, but a reproducible association is not demonstrable in a significant way.

Response characteristics of vestibular evoked myogenic potentials recorded over splenius capitis in young adults and adolescents

Background and objectivesExamine vestibular evoked myogenic potential (VEMP) responses recorded from surface electrodes over Splenius Capitis (SPC) in a seated position. Specific aims: (1) validate response characteristics of VEMP recordings from surface electrodes over Sternocleidomastoid (SCM) and over SCP and (2) assess age effects on responses in adolescents and young adults. Materials and methodsSimultaneous surface VEMP was recorded bilaterally from electrodes placed over the dorsal neck musculature at a location known from previous work to record from SPC in 15 healthy participants during trials with head rotation toward and away from the stimulated ear. VEMP was also recorded from electrodes over SCM, ipsilateral to the stimulus ear, in the same participants in a supine, head lift/turn position. ResultsResponse amplitudes significantly increased with contraction strength and decreased with age. Participants were able to maintain sufficient contraction strength (amplitude) with head rotation to reliably measure over SPC. Normalized response amplitudes measured from electrodes over contralateral SPC were largest with head rotation contralateral to the stimulus ear. Normalized amplitudes and peak latencies were comparable to the same measures from SCM obtained in supine, head lift/turn position. ConclusionsOtolith generated myogenic responses can be recorded seated from electrodes over the dorsal neck with head rotation contralateral to the stimulus ear. In this position, contralateral recordings are consistent with responses known from previous work to arise from SPC; ipsilateral recordings may include crosstalk from activated muscles nearby, including ipsilateral SCM. Overall, techniques targeting contralateral SPC during contralateral head turn may provide additional methods of recording VEMPs.

Is There a Safe Level for Recording Vestibular Evoked Myogenic Potential? Evidence From Cochlear and Hearing Function Tests.

There is a growing concern among the scientific community about the possible detrimental effects of signal levels used for eliciting vestibular evoked myogenic potentials (VEMPs) on hearing. A few recent studies showed temporary reduction in amplitude of otoacoustic emissions (OAE) after VEMP administration. Nonetheless, these studies used higher stimulus levels (133 and 130 dB peak equivalent sound pressure level [pe SPL]) than the ones often used (120 to 125 dB pe SPL) for clinical recording of VEMP. Therefore, it is not known whether these lower levels also have similar detrimental impact on hearing function. Hence, the present study aimed at investigating the effect of 500 Hz tone burst presented at 125 dB pe SPL on hearing functions. True experimental design, with an experimental and a control group, was used in this study. The study included 60 individuals with normal auditory and vestibular system. Of them, 30 underwent unilateral VEMP recording (group I) while the remaining 30 did not undergo VEMP testing (group II). Selection of participants to the groups was random. Pre- and post-VEMP assessments included pure-tone audiometry (250 to 16,000 Hz), distortion product OAE, and subjective symptoms. To simulate the time taken for VEMP testing in group I, participants in group II underwent these tests twice with a gap of 15 minutes. No participant experienced any subjective symptom after VEMP testing. There was no significant interear and intergroup difference in pure-tone thresholds and distortion product OAE amplitude before and after VEMP recording (p > 0.05). Furthermore, the response rate of cervical VEMP was 100% at stimulus intensity of 125 dB pe SPL. Use of 500 Hz tone burst at 125 dB pe SPL does not cause any temporary or permanent changes in cochlear function and hearing, yet produces 100% response rate of cervical VEMP in normal-hearing young adults. Therefore, 125 dB pe SPL of 500 Hz tone burst is recommended as safe level for obtaining cervical VEMP without significantly losing out on its response rate, at least in normal-hearing young adults.

Vestibular Evoked Myogenic Potentials Are Abnormal in Idiopathic REM Sleep Behavior Disorder

Objectives: To investigate brainstem function in idiopathic REM sleep Behavior Disorder (iRBD), a condition occurring as a result of a derangement of connections within brainstem structures, with a battery of Vestibular Evoked Myogenic Potentials (VEMPs), neurophysiological tools suited for the functional investigation of the brainstem. Neurophysiological data were correlated with clinical characteristics of patients.Methods: Twenty patients with iRBD and 22 healthy controls underwent cervical (cVEMP), masseter (mVEMP) and ocular (oVEMP) VEMP recording. Patients were assessed clinically according to presence of motor as well as non-motor symptoms such as constipation, depression, and hyposmia. Also, they were screened for postural instability through the Berg Balance Scale (BBS). VEMPs were categorized as for increasing degrees of abnormalities, namely latency delay, amplitude reduction and absence; a VEMP score was built accordingly.Results: Compared with controls, iRBD had higher rates of abnormalities both in the VEMP battery (iRBD 75%, Controls 23%; p < 0.01) as well as in each single VEMP (cVEMP: 45 vs. 5%; mVEMP: 65 vs. 13.6%; oVEMP: 50 vs. 5%; p < 0.01), which exhibited significantly lower amplitudes (cVEMP and oVEMP: p < 0.0001; mVEMP: p = 0.001) in iRBD. Within altered reflexes, absence was predominant in oVEMP (81%), amplitude reduction in mVEMP (50%) and cVEMP (70%). Severity of VEMP alterations was significantly higher in iRBD compared with controls (p < 0.05 for all VEMPs), as indicated by the larger VEMP scores in the former. The oVEMP score correlated inversely with poor performances on the BBS.Conclusion: VEMPs unveil consistent and extensive brainstem abnormalities in iRBD patients. Further studies are warranted for testing the potential of VEMPs in the monitoring of the evolution of iRBD over time.

Prevention of recurrent benign paroxysmal positional vertigo (BPPV)

Insufficient study of BPPV etiological factors results in a high rate of the disease recurrence, which impairs the patients’ life quality. The objective of this study was to improve the efficacy of BPPV treatment based on identification of predictive factors of disease recurrence by means of assessment of the severity of utriculus dysfunction and the study of calcium-phosphorus exchange disorders. We conducted a study of 25(OH) D level and registration of ocular BPPVs 7 days after the treatment in 98 patients with idiopathic posterior semicircular canal (PSC) BPPV (the index group, IG) and assessment of the effect of the detected changes on the frequency of the disease recurrences. To assess the prevalence of calcium metabolism disorders in the population, we arranged a control group (CG) of 30 healthy volunteers, identical in terms of socio-demographic characteristics. The prevalence of vitamin D deficiency (25 (OH)D less than 20 ng/ml) in the index group was 67% (n = 66), in the control group it constituted 10% (n = 3). The dependence of idiopathic BPPV incidence on 25(OH)D deficiency (chi-square test) was statistically significant (p &lt; 0.05), indicating that the 25(OH)D deficiency is a risk factor of idiopathic BPPV development. During registration of vestibular evoked myogenic potential (VEMP) 7 days after treatment, the P1N1 peaks of ocular VEMPs were not recorded on the affected side in 14(14%) patients, the clinically significant (&gt;40%) asymmetry in the amplitude of the ocular VEMP was identified in 25(26%) patients, the restoration of symmetry occurred in 59 (60%) patients. Within 12 months, the relapse occurred in 28 (28.5%) patients with BPPV. The relapse occurred in all patients with no P1N1 peaks of ocular VEMP on the 7th day after treatment (n = 14), in 56% (n = 13) of the patients maintaining clinically significant asymmetry (&gt;40%) of the ocular VEMP amplitude on the 7th day after treatment, in 2% (n = 1) patients with the restored symmetry of the ocular VEMP amplitude. The dependence of frequency of idiopathic BPPV recurrence development on existence of clinically significant asymmetry (&gt;40%) of the ocular VEMP amplitude on the 7th day after treatment (chi-square test) was statistically significant (p &lt;0.01). The combined determination of 25(OH)D level which is the etiological factor of idiopathic BPPV, and the functional state of the utriculus by means of ocular VEMP recording makes it possible to estimate the risk of a BPPV recurrence and to develop the preventive measures of the disease recurrence.

Simultaneous recording of cervical and ocular vestibular-evoked myogenic potentials.

To increase clinical application of vestibular-evoked myogenic potentials (VEMPs) by reducing the testing time by evaluating whether a simultaneous recording of ocular and cervical VEMPs can be achieved without a loss in diagnostic sensitivity and specificity. Simultaneous recording of ocular and cervical VEMPs on each side during monaural stimulation, bilateral simultaneous recording of ocular VEMPs and cervical VEMPs during binaural stimulation, and conventional sequential recording of ocular and cervical VEMPs on each side using air-conducted sound (500 Hz, 5-millisecond tone burst) were compared in 40 healthy participants (HPs) and 20 patients with acute vestibular neuritis. Either simultaneous recording during monaural and binaural stimulation effectively reduced the recording time by ≈55% of that for conventional sequential recordings in both the HP and patient groups. The simultaneous recording with monaural stimulation resulted in latencies and thresholds of both VEMPs and the amplitude of cervical VEMPs similar to those found during the conventional recordings but larger ocular VEMP amplitudes (156%) in both groups. In contrast, compared to the conventional recording, simultaneous recording of each VEMP during binaural stimulation showed reduced amplitudes (31%) and increased thresholds for cervical VEMPs in both groups. The results of simultaneous recording of cervical and ocular VEMPs during monaural stimulation were comparable to those obtained from the conventional recording while reducing the time to record both VEMPs on each side. NCT03049683.

P250 Simultaneous recording of cervical and ocular vestibular-evoked myogenic potentials

Objective To increase clinical application by reducing the testing time for recording vestibular-evoked myogenic potentials (VEMPs), we evaluated whether a simultaneous recording of ocular and cervical VEMPs after monaural and binaural stimulation can be achieved without a loss in diagnostic sensitivity and specificity. Methods Using randomized cross-over trials, 40 healthy subjects (HS) and 20 patients with acute vestibular neuritis underwent simultaneous recording of ocular and cervical VEMPs on each side during monaural stimulation, bilateral simultaneous recording of ocular VEMPs and cervical VEMPs during binaural stimulation, and conventional sequential recording of ocular and cervical VEMPs on each side using air-conducted sound (500 Hz, 5 ms tone-burst). We compared the time required to test and VEMP parameters among the study conditions. Clinical trial registration: NCT03049683. Results Either simultaneous recording during monaural and binaural stimulation effectively reduced the recording time by about 55% of that for conventional sequential recordings in both HS and patients groups. The simultaneous recording with monaural stimulation resulted in the latencies and thresholds of both VEMPs and amplitude of cervical VEMPs similar to those found during the conventional recordings in both groups, but larger oVEMP amplitude (156%) in HS. In contrast, compared to the conventional recording, simultaneous recording of each VEMP during binaural stimulation showed reduced amplitudes (31%) and increased thresholds for cervical VEMPs in both groups. Conclusion The results of simultaneous recording of cervical and ocular VEMPs during monaural stimulation were comparable to those obtained from the conventional recording while reducing the time to record both VEMPs on each side.

The Management of the Vertiginous Patient

In neuro-otology, history taking still represents the most important instrument. It comprises type, direction, duration, intensity and influencing factors of dizziness, vertigo and balance problems as well as accompanying symptoms of the otologic and neurologic systems. A distinction in a) acute persisting, b) episodic with or without positioning dependence and c) chronic vertigo can provide a first diagnostic differentiation. The clinical exam contains an otolaryngologic and neurologic assessment with focus on ocular motor function, nystagmus, head impulse testing, balance function tests, cerebellar signs and positioning tests. Helpful laboratory tests are tests of orthostatic function, pure tone audiometry, bithermal calorics, video head impulse test and in specific situations nystagmography and the recording of vestibular-evoked myogenic potentials. Often a brain magnetic resonance tomography needs to be added. In several cases a multi-disciplinary approach is recommended. Therapeutical options are physical therapy as vestibular rehabilitation or repositioning procedures, drugs or surgery, albeit the level of evidence of some therapies currently being applied is far from satisfactory.

Vestibular evoked myogenic potentials in pediatric patients with familial Mediterranean fever

ObjectivesWe aimed to investigate whether the chronic autoinflammatory process in familial Mediterranean fever (FMF), which affects numerous systems, results in vestibular dysfunction in pediatric patients being followed up for diagnosis of FMF using VEMP recordings. Methods30 patients (60 ears) diagnosed with FMF and 20 (40 ears) healthy volunteers were included in the study. Following routine ear, nose, and throat examination, transient-evoked otoacoustic emissions (TEOAE) and vestibular-evoked myogenic potential (VEMP) tests were performed. ResultsA total of 30FMF pediatric patients (13 male, 17 female) and 20 controls (8 male, 12 female) were included in the study. The mean age of FMF patients was 12.13±2.88 years, while that of the controls was 12.90±2.80 years. All of the otoacoustic emission results of the patient and control groups were “pass VEMP recordings received in both ears of patients with FMF (60 ears) and both ears of controls (40 ears). There was no statistically significant difference for latencies or amplitudes for either patients or controls (p>0.05). ConclusionIn order to research the effect of FMF on vestibular functions, we measured VEMP. However, we did not detect alterations of VEMP in FMF patients.

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.

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.

Vestibular evoked myogenic potential responses in obstructive sleep apnea syndrome.

Obstructive sleep apnea syndrome (OSAS) provokes oxidative stress and ischemia, which affects the central nervous system. The degeneration of neurons in the brainstem due to periodic hypoxia can be evaluated by vestibular and audiologic tests. The objective of this study is to determine brainstem damage in severe OSAS patients with the help of vestibular evoked myogenic potential (VEMP) responses. Prospective, randomize, double-blind. Research-training hospital. We compared cervical vestibular evoked myogenic potential (cVEMP) responses between severe OSAS patients and a control group. 54 patients were included and divided into the OSAS group, with severe OSAS (apnea-hypopnea index, AHI >70), and a control group with snoring without OSAS (AHI <5). Both groups underwent cVEMP. Bilateral recordings with simultaneous binaural logon stimulations were used during VEMP recordings. The existing p1n1 and n2p2 responses, p1, n1, n2, and p2 latencies and amplitudes, and p1n1 and n2p2 intervals were measured. Statistically significant differences were revealed between patients and controls for the response rate of the p1n1, n2p2 and p1n1, n2p2 amplitudes. There were no significant differences between the two groups with respect to the latencies of p1, n1, n2 and p2, or the p1n1 and n2p2 intervals. The VEMP response rate was lower in severe OSAS patients, and all amplitudes were shorter than in healthy subjects. VEMP recordings in severe OSAS subjects demonstrates abnormalities in brainstem pathways. It appears that brainstem damage in severe OSAS can be detected by cVEMP recordings.

Vestibular Evoked Myogenic Potential Findings in Multiple Sclerosis

IntroductionMultiple sclerosis is an inflammatory disease involving the occurrence of demyelinating, chronic neurodegenerative lesions in the central nervous system. We studied vestibular evoked myogenic potentials (VEMPs) in this pathology, to allow us to evaluate the saccule, inferior vestibular nerve and vestibular-spinal pathway non-invasively. MethodsThere were 23 patients diagnosed with multiple sclerosis who underwent VEMP recordings, comparing our results with a control group consisting of 35 healthy subjects. We registered p13 and n23 wave latencies, interaural amplitude difference and asymmetry ratio between both ears. Subjects also underwent an otoscopy and audiometric examination. ResultsThe prolongation of p13 and n23 wave latencies was the most notable characteristic, with a mean p13 wave latency of 19.53ms and a mean latency of 30.06ms for n23. In contrast, the asymmetry index showed no significant differences with our control group. ConclusionsIn case of multiple sclerosis, the prolongation of the p13 and n23 VEMP wave latencies is a feature that has been attributed to slowing of conduction by demyelination of the vestibular-spinal pathway. In this regard, alteration of the response or lack thereof in these potentials has a locator value of injury to the lower brainstem.

Hallazgos de potenciales vestibulares miogénicos evocados en la esclerosis múltiple

IntroductionMultiple sclerosis is an inflammatory disease involving the occurrence of demyelinating, chronic neurodegenerative lesions in the central nervous system. We studied vestibular evoked myogenic potentials (VEMPs) in this pathology, to allow us to evaluate the saccule, inferior vestibular nerve and vestibular-spinal pathway non-invasively. MethodsThere were 23 patients diagnosed with multiple sclerosis who underwent VEMP recordings, comparing our results with a control group consisting of 35 healthy subjects. We registered p13 and n23 wave latencies, interaural amplitude difference and asymmetry ratio between both ears. Subjects also underwent an otoscopy and audiometric examination. ResultsThe prolongation of p13 and n23 wave latencies was the most notable characteristic, with a mean p13 wave latency of 19.53 milliseconds and a mean latency of 30.06 milliseconds for n23. In contrast, the asymmetry index showed no significant differences with our control group. ConclusionsIn case of multiple sclerosis, the prolongation of the p13 and n23 VEMP wave latencies is a feature that has been attributed to slowing of conduction by demyelination of the vestibular-spinal pathway. In this regard, alteration of the response or lack thereof in these potentials has a locator value of injury to the lower brainstem.

The Role of Cervical and Ocular Vestibular-Evoked Myogenic Potentials in the Follow-Up of Vestibular Neuritis

This study evaluates the recovery of vestibular nerve function after vestibular neuritis (VN) by vestibular-evoked myogenic potentials (VEMPs). Twenty-six patients with the diagnosis of VN were included. All patients underwent ocular VEMP (oVEMP) and cervical VEMP (cVEMP) recordings, at 6 days and 6 months from the onset of the symptoms. Of the 26 patients, 14 showed improvement on oVEMP at month 6 (group 1), and 12 showed no change or worsening on oVEMP at 6 months (group 2). At the same time, there was no change in the amplitudes of the cVEMP on either healthy or affected sides in both groups. Inability to perform the Fukuda test, and chronic white matter supratentorial lesions present on brain magnetic resonance imaging (MRI) were more frequent in patients with worse outcome on oVEMP (P = 0.044 and 0.045, respectively). Although involvement of the inferior branch of the vestibular nerve was not associated with oVEMP outcome, oVEMP latencies (N10 and P13) were associated with improvement or worsening in oVEMP amplitudes, showing that prolonged latencies correlate with 6-month improvement in oVEMP amplitudes (Pearson correlation -0.472, P = 0.041 and -0.580, P = 0.009, respectively). This study identified clinical, MRI and neurophysiological predictors of recovery in patients with superior VN, and offers additional insight into, and better understanding of, the role of VEMP in diagnosis and prognosis of patients with VN. Further studies are needed to validate this diagnostic procedure and to assess its clinical usefulness in VN management.