cVEMP Responses Research Articles

Objective methods to measure vestibular evoked myogenic potential response saccular tuning curves

Objective: To detect cervical vestibular evoked myogenic potential (cVEMP) responses using objective statistical approaches and to apply this approach to estimate saccular frequency-tuning curves in volunteers and Ménière’s disease (MD) patients.Design: Estimates of cVEMP threshold were carried out by 3 expert raters at 500 Hz and compared to objective threshold estimates (using Hotelling’s T2 [HT2] and Fsp). Saccular tuning curves were objectively estimated.Study sample: Objective and subjective estimates of cVEMP response thresholds were compared for 13 normal hearing adults. Objective measurement of saccular tuning curves was explored in 20 healthy adults and 15 patients with MD.Results: Significant variability was seen between subjective estimates of cVEMP thresholds. Objective analysis with the HT2 test was more sensitive than 2 of 3 experts in detecting responses. The measurement time of cVEMP was considerably reduced with the HT2 test. Objective saccular tuning curves in volunteers showed strongest responses at 500 Hz. A flatter tuning curve was seen for MD patients.Conclusions: There is significant variability in subjective estimations of cVEMP thresholds. Objective analysis methods are more sensitive than subjective analysis, can detect responses rapidly and have potential to reduce variability in threshold estimates, hence they appear well suited to measure cVEMP tuning curves.

Effects of cochlear implants on otolith function as evaluated by vestibulo-ocular reflex and vestibular evoked myogenic potentials

ObjectiveThe aim of this study was to investigate whether the insertion of an implant into the cochlea is accompanied by a deterioration in otolith function. Cervical and ocular vestibular evoked myogenic potentials (cVEMP and oVEMP) and linear vestibulo-ocular reflex (lVOR) during eccentric rotation were assessed before and after cochlear implantation (CI) to evaluate otolith function. MethodsTwelve patients with bilateral severe sensorineural hearing loss who had undergone CI surgery in our hospital between May 2016 and November 2017 were included in this study. cVEMP and oVEMP were assessed using the asymmetry ratio (AR), calculated with the following formula: [(peak-to-peak amplitude calculated as the sum of the p13 and n23 amplitudes in the non-operated side) − (that in the operated side)]/[(that in the non-operated side) + (that in the operated side)]. The ratio of VOR gain during eccentric rotation against VOR gain during center rotation was used to assess lVOR. For eccentric rotation, patients were rotated while displaced from the axis of rotation. At the same time, linear acceleration stimulated the utricle and induced lVOR. All patients underwent cVEMP and oVEMP tests and center and eccentric rotation tests before and about 30days after CI surgery. ResultsThree patients with absent cVEMP responses before surgery were excluded, leaving pre-surgery cVEMP results for 9/12 patients. In five of these patients, the AR of cVEMP increased after CI, indicating that saccular function, as evaluated by cVEMP, did not deteriorate significantly postoperatively. One patient with an absent oVEMP response before CI was excluded, leaving pre-surgery oVEMP results for 11/12 patients. In 10 of these patients, the AR of oVEMP increased after CI surgery, indicating that utricular function, as evaluated by oVEMP, deteriorated significantly postoperatively. However, because the ratio of VOR gain during eccentric rotation against VOR gain during center rotation did not become worse after CI, utricular function, as evaluated by lVOR, did not deteriorate significantly postoperatively. Symptoms of vertigo became worse after CI in two of the 12 patients. ConclusionCI does not cause a deterioration in saccular function, as evaluated by cVEMP. Although CI does cause a deterioration in utricular function in oVEMP tests, this is not consistent in lVOR tests. These results indicate that CI causes a slight deterioration in utricular function that is insufficient to cause vertigo or deterioration of lVOR.

Cervical Vestibular Evoked Myogenic Potential in Children with Auditory Neuropathy Spectrum Disorder of prelingual onset

children with ANSD of pre-lingual onset, and to compare c-VEMP findings to those in children with non- ANSD sensorineural (non -ANSD SNHL) of pre-lingual onset.Methods: The study included 35 children with bilateral ANSD, and 32 children with bilateral non-ANSD SNHL of severe, severe to profound, or profound degree. Both groups of children had the onset SNHL pre-lingually. The study also included 15 control children. Mean age and SD were 6.9 years ± 2.9 for the control children, 7.8 years ± 3.1 for the ANSD children, and 8.8 years ± 3.4 for the non-ANSD children. All participant children were subjected to full history taking, otological examination, hearing assessment, recording for auditory brainstem response and cochlear microphonics, Distortion product otoacoustic emission recording, and c-VEMP recording.Results: Results showed that the vast majority of ANSD children (88% of ears) had intact c-VEMP response. Moreover, there was no statistically significant difference between the ANSD children and control children as regards the VEMP parameters (P1-N1 amplitude, asymmetric ratio, P1 latency, N1 latency, and inter-aural latency differences of P1 and N1). There was no statistically significant difference between ANSD with risk factors and those without risk factors as regards VEMP parameters. Results indicate that the vast majority of ANSD children with pre-lingual onset, even those with risk factors, have normal saccular function along with intact and normally functioning inferior vestibular nerve, and the other central connections responsible for the VEMP response. On the other hand, 53.1% of ears children with non-ANSD SNHL had an absent c-VEMP response, and 46.9% of ears had intact and normal c-VEMP response. The overall results indicate that while the pathology of non-ANSD SNHL involves the saccule in more than half of children, the underlying pathology ANSD spares the saccule and its central connection.Conclusions: Results suggest that the site of lesion in ANSD children of pre-lingual onset is restricted to the auditory system with sparing the vestibular system in the majority of children. These findings support the choice of cochlear implantation as the best line of management in children with ANSD, even in the presence of risk factors. So cochlear implantation in children with ANSD is safer than children with SNHL as there will be no fear of bilateral saccular dysfunction in the case saccular damage occurred in the surgery side as a result of the surgical procedure.

Vestibular dysfunction is a manifestation of 22q11.2 deletion syndrome.

The 22q11.2 deletion syndrome (22q11.2DS) is the second most common cause of developmental delay after Down syndrome. Impaired cognitive development is highly prevalent, but also motor abnormalities such as hypotonia and delays in achieving motor milestones are described. Instability is frequently detected in children, adolescents, and adults and is mostly attributed to their limited motor performance. Until now, vestibular function has not been investigated in these patients, despite the growing evidence that they often have inner ear malformations. The aim of this prospective study was to identify the presence and character of vestibular dysfunction in 22q11.2DS. We investigated 23 subjects with proven 22q11.2DS, older than the age of 12. We performed caloric testing and pendular rotation chair tests with videonystagmography, cervical vestibular-evoked myogenic potential (c-VEMP)-testing, and posturography. Additional otoscopy and audiometry were performed on all subjects. We found a unilateral caloric hypofunction in 55% of patients, a certain absent c-VEMP response in 15% of ears, an inconclusive c-VEMP response in 33% of ears, and abnormal posturography in 68% of patients, of whom 42% displayed a typical vestibular pattern. Remarkably, 90% revealed uni- or bilateral weak caloric responses, independent of caloric symmetry. Vestibular dysfunction is frequent in subjects with 22q11.2DS. This knowledge should be taken into account when assessing motor performance in these patients. Additional larger studies are needed to determine whether this dysfunction implicates a therapeutic potential.

Otolith dysfunction in recurrent benign paroxysmal positional vertigo after mild traumatic brain injury

Background: The pathogenesis of recurrence of traumatic benign paroxysmal positional vertigo (BPPV) is poorly understood by far.Objectives: To evaluate the value of secondary otolith dysfunction using vestibular evoked myogenic potential (VEMP) test in the pathogenesis of recurrence of BPPV after mild traumatic brain injury (mTBI).Material and methods: We reviewed 42 patients with BPPV after mTBI. According to recurrence, patients were divided into two groups. Both cervical VEMP (cVEMP) and ocular VEMP (oVEMP) tests were performed on all of them.Results: We detected abnormal cVEMP responses in four (26.7%) patients in the recurrent BPPV group after mTBI and five (18.5%) patients in the non-recurrent BPPV group after mTBI, and there was no significant difference between both groups. We detected abnormal oVMEP responses in nine (60.0%) patients in the recurrent BPPV group after mTBI and six (22.2%) patients in the non-recurrent BPPV group after mTBI, and there was a significant difference between both groups.Conclusions and significance: Our study shows that oVEMP abnormalities in recurrent BPPV group after mTBI are significantly higher than those in non-recurrent BPPV group after mTBI. Therefore, we can conclude that secondary utricular dysfunction may be a potential pathogenesis of recurrence of traumatic BPPV.

Vestibular Evoked Myogenic Potentials (VEMP) in patients with Multiple Sclerosis

Background: multiple sclerosis (MS) is a chronic demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged and this damage disrupts the ability of parts of the nervous system to communicate, resulting in a range of signs and symptoms. Objective: this study aimed to assess cervical vestibular evoked myogenic potentials (cVEMP) in patient with multiple sclerosis and to demonstrate the value of cVEMP as a good method for the assessment of vestibulospinal tract in patients with MS. Patients and Methods: to achieve this target, we enrolled 50 subject: 30 patients diagnosed as MS in addition to 20 healthy control. The cVEMP response was evaluated for the presence of positive (p1) and negative (n1) peaks of the first biphasic wave complex; latency (p1 and n1 latency) and peak to peak amplitude. The bilateral otoscopy was normal in cases and controls, with no middle or outer ear disease that could bias the study results being found. The pure tone audiometry showed levels of hearing compatible with normal hearing in the 20 healthy subjects, with hearing thresholds that did not exceed 25 dB for any individual. Results: the present results showed that 60 % of MS patients had VEMP abnormalities (absent responses and/or prolonged latencies). In the present study, patients with absent VEMP wave were found to have significantly higher disease duration. In the present study, the absence of P13–N23 waves were more frequent in patients with greater EDSS score, and also absence of P13–N23 waves were more frequent in patients with MS with vestibular symptoms and greater disability. Conclusion: we can say that in patients with MS in which demyelination has extended to the vestibulospinal tract, there is going to be a prolongation of the p13 and n23 wave. In fact, this increase in the p13 and n23 latencies is clear in the patients with MS in comparison to the control group.

Vestibular Evoked Myogenic Potentials (VEMP) in patients with Multiple Sclerosis

Background: multiple sclerosis (MS) is a chronic demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged and this damage disrupts the ability of parts of the nervous system to communicate, resulting in a range of signs and symptoms. Objective: this study aimed to assess cervical vestibular evoked myogenic potentials (cVEMP) in patient with multiple sclerosis and to demonstrate the value of cVEMP as a good method for the assessment of vestibulospinal tract in patients with MS. Patients and Methods: to achieve this target, we enrolled 50 subject: 30 patients diagnosed as MS in addition to 20 healthy control. The cVEMP response was evaluated for the presence of positive (p1) and negative (n1) peaks of the first biphasic wave complex; latency (p1 and n1 latency) and peak to peak amplitude. The bilateral otoscopy was normal in cases and controls, with no middle or outer ear disease that could bias the study results being found. The pure tone audiometry showed levels of hearing compatible with normal hearing in the 20 healthy subjects, with hearing thresholds that did not exceed 25 dB for any individual. Results: the present results showed that 60 % of MS patients had VEMP abnormalities (absent responses and/or prolonged latencies). In the present study, patients with absent VEMP wave were found to have significantly higher disease duration. In the present study, the absence of P13–N23 waves were more frequent in patients with greater EDSS score, and also absence of P13–N23 waves were more frequent in patients with MS with vestibular symptoms and greater disability. Conclusion: we can say that in patients with MS in which demyelination has extended to the vestibulospinal tract, there is going to be a prolongation of the p13 and n23 wave. In fact, this increase in the p13 and n23 latencies is clear in the patients with MS in comparison to the control group.

Usefulness of Intravenous Gadolinium Inner Ear MR Imaging in Diagnosis of M\xe9ni\xe8re\u2019s Disease

This study aimed to investigate the usefulness of the intravenous gadolinium enhanced inner ear magnetic resonance imaging (IV-Gd inner ear MRI) in diagnosing Ménière’s disease(MD) and find a correlation between the degree of endolymphatic hydrops(EH) and the audiovestibular tests. Total 29 patients diagnosed with unilateral definite MD were enrolled. All patients underwent IV-Gd inner ear MRI and auditory and vestibular function tests such as pure tone audiometry (PTA), electrocochleography (ECoG), cervical vestibular evoked myogenic potential (cVEMP) and caloric test. The hydrops ratio in the cochlea and vestibule were significantly higher in the affected side than the unaffected side (p < 0.001). Average pure-tone thresholds for 0.5, 1 k, 2 k, and 4 k Hz correlated significantly with cochlear and vestibular hydrops (p < 0.01) in the affected side. When comparing the SP/AP ratio of ECoG with hydrops ratio in the vestibule, the affected and unaffected ears showed a significant difference (p < 0.05). Similarly, the results of the caloric test also showed a significant correlation (p < 0.05) with relative vestibular hydrops. However, the cVEMP response was not related to the hydrops ratio in the cochlea or vestibule. This study presents pertinent data with appropriate correlations with auditory vestibular functional testing which demonstrates the usefulness of IV-Gd inner ear MRI as a diagnostic method for visualizing the endolymphatic hydrops in MD.

Toward Optimizing VEMP: Calculating VEMP Inhibition Depth With a Generic Template.

Cervical vestibular evoked myogenic potentials (cVEMP) indirectly reveal the response of the saccule to acoustic stimuli through the inhibition of sternocleidomastoid muscle electromyographic response. VEMP inhibition depth (VEMPid) is a recently developed metric that estimates the percentage of saccular inhibition. VEMPid provides both normalization and better accuracy at low response levels than amplitude-normalized cVEMPs. Hopefully, VEMPid will aid in the clinical assessment of patients with vestibulopatholgy. To calculate VEMPid a template is needed. In the original method, a subject's own cVEMP was used as the template, but this method can be problematic in patients who do not have robust cVEMP responses. We hypothesize that a "generic" template, created by assembling cVEMPs from healthy subjects, can be used to compute VEMPid, which would facilitate the use of VEMPid in subjects with pathological conditions. A generic template was created by averaging cVEMP responses from 6 normal subjects. To compare VEMPid calculations using a generic versus a subject-specific template, cVEMPs were obtained in 40 healthy subjects using 500, 750, and 1000 Hz tonebursts at sound levels ranging from 98 to 123 dB peSPL. VEMPids were calculated both with the generic template and with the subject's own template. The ability of both templates to determine whether a cVEMP was present or not was compared with receiver operating characteristic curves. No significant differences were found between VEMPid calculations using a generic template versus using a subject-specific template for all frequencies and sound levels. Based on the receiver operating characteristic curves, the subject-specific and generic template did an equally good job at determining threshold. Within limits, the shape of the generic template did not affect these results. A generic template can be used instead of a subject-specific template to calculate VEMPid. Compared with cVEMP normalized by electromyographic amplitudes, VEMPid is advantageous because it averages zero when there is no sound stimulus and it allows the accumulating VEMPid value to be shown during data acquisition as a guide to deciding when enough data has been collected.

Ocular and Cervical Vestibular Evoked Myogenic Potentials in Patients With Vestibular Migraine.

To evaluate the relationship between normal and abnormal ocular vestibular evoked myogenic potentials (oVEMP) and cervical vestibular evoked myogenic potentials (cVEMP) in patients with and without vestibular migraine (VM). Retrospective review of oVEMP and cVEMP results in patients with vestibular disorders who were assessed clinically and completed vestibular function studies. Data were extracted from a deidentified RedCap Repository. Tertiary care multispecialty medical center. Subjects were 212 consecutive adults meeting prespecified inclusion criteria who were evaluated in the Balance Disorders Clinic at Vanderbilt University Medical Center between 2011 and 2017. Patients with bilaterally absent VEMPs were excluded from the study. None. Proportions of subjects with or without VM in one of the following four test outcomes: normal cVEMP/normal oVEMP, abnormal cVEMP/abnormal oVEMP, abnormal cVEMP/normal oVEMP, and normal cVEMP/abnormal oVEMP. There was a significant relationship between VM and cVEMP and oVEMP test outcomes. Patients with VM are more likely than subjects with vestibular disorders other than migraine to exhibit normal cVEMP responses in the presence of unilaterally abnormal oVEMP responses. Such a VEMP pattern may be a biomarker of VM and further supports a possible pathophysiologic relationship between the utriculo-ocular reflex and VM.

The effect of cochlear implants on vestibular-evoked myogenic potential responses and postural stability

ObjectiveCurrent spread by electrical stimulation via inserted cochlear implant (CI) electrodes and the consequential increase in sound input can affect the equilibrium of patients. The aim of the present study was to clarify the effect of CIs on the equilibrium of patients through cervical vestibular-evoked myogenic potential (cVEMP) testing and static stabilometry performed with the CIs turned on (CI-on) and off (CI-off). MethodsThis prospective study included nine adult patients who underwent unilateral cochlear implantation surgery at our institution. cVEMP testing and stabilometry were performed before surgery and repeated after surgery in the CI-on and CI-off modes. ResultsBefore surgery, cVEMP responses were diminished in five of the nine patients (55.6%), while the results of stabilometry were poor in six patients (66.7%). After surgery, both cVEMP responses and stabilometry findings in the CI-off mode exhibited significant deterioration relative to the preoperative results (cVEMP: 7/9, 77.8%; stabilometry: 7/9, 77.8%). However, in the CI-on mode, there were significant improvements in both test results relative to the findings in the CI-off mode for all patients. ConclusionCIs compensated for the surgical trauma-induced deterioration in static postural stability when turned on, resulting in a considerable improvement. Our findings suggest that postoperative cVEMP testing in the CI-on and CI-off modes will enable more accurate assessment of the saccule–inferior vestibular nerve system function after cochlear implant surgery.

Assessment of vestibular-evoked myogenic potentials and video head impulse test in type 2 diabetes mellitus patients with or without polyneuropathy.

This study aimed to compare cervical vestibular-evoked myogenic potentials (cVEMP), ocular vestibular-evoked myogenic potentials (oVEMP) and video head impulse test (vHIT) results between patients with type 2 diabetes mellitus (DM) or diabetic polyneuropathy (DPN) and healthy controls to determine vestibular end-organ pathologies. The participants in the present study consisted of three groups: the type 2 DM group (n = 33 patients), the DPN group (n = 33 patients), and the age- and sex-matched control group (n = 35). Cervical VEMP, oVEMP and vHIT were performed for each participant in the study and test results were compared between the groups. Peak-to-peak amplitudes of cVEMP (p13-n21) and oVEMP (n10-p15) were significantly lower in the DM and DPN groups than the control group. The values of vHIT were not statistically different between the groups. To our knowledge, the present study is the first report investigating oVEMP and cVEMP responses combined with vHIT findings in patients with DM and DPN. Vestibular end-organ pathologies can be determined via clinical vestibular diagnostic tools in spite of prominent vestibular symptoms in patients with type 2 DM as well as patients with DPN.

Effects of vertebrobasilar insufficiency on cVEMP responses

Effects of vertebrobasilar insufficiency on cVEMP responses

Effects of vertebrobasilar insufficiency on cVEMP responses

Effects of vertebrobasilar insufficiency on cVEMP responses

Founder mutation in IKBKAP gene causes vestibular impairment in familial dysautonomia

ObjectiveTo assess vestibular function in patients with familial dysautonomia (FD), a hereditary sensory and autonomic neuropathy – caused by a mutation in the IKBKAP gene (c.2204 + 6 T>C) – and characterized by marked gait ataxia. MethodsCervical and vestibular evoked myogenic potentials (cVEMPs and oVEMPs) were recorded from the sternocleidomastoid (SCM) and extraocular muscles in 14 homozygous patients, 2 heterozygous patients, and 15 healthy controls during percussion of the forehead. ResultscVEMP and oVEMP amplitudes were significantly lower, and peak latencies significantly delayed, in the FD patients. There were no differences in overall EMG during attempted maximal voluntary contractions of the SCM muscle, suggesting intact efferent function. The two heterozygotes with a minor haplotype missense (R696P) mutation in exon 19 of the IKBKAP gene had cVEMP responses less affected than the homozygous. ConclusionsThe founder mutation in the IKBKAP gene affects the development of vestibular afferent pathways, leading to attenuated cVEMPs. SignificanceVestibular abnormalities may contribute to the gait ataxia in FD.

Sensitivity and Specificity of Clinical and Laboratory Otolith Function Tests.

To evaluate clinic based and laboratory tests of otolith function for their sensitivity and specificity in demarcating unilateral compensated complete vestibular deficit from normal. Prospective cross-sectional study. Tertiary care hospital vestibular physiology laboratory. Control group-30 healthy adults, 20-45 years age; Case group-15 subjects post vestibular shwannoma excision or post-labyrinthectomy with compensated unilateral complete audio-vestibular loss. Otolith function evaluation by precise clinical testing (head tilt test-HTT; subjective visual vertical-SVV) and laboratory testing (headroll-eye counterroll-HR-ECR; vesibular evoked myogenic potentials-cVEMP). Sensitivity and specificity of clinical and laboratory tests in differentiating case and control subjects. Measurable test results were universally obtained with clinical otolith tests (SVV; HTT) but not with laboratory tests. The HR-ECR test did not indicate any definitive wave forms in 10% controls and 26% cases. cVEMP responses were absent in 10% controls.HTT test with normative cutoff at 2 degrees deviations from vertical noted as 93.33% sensitive and 100% specific. SVV test with normative cutoff at 1.3 degrees noted as 100% sensitive and 100% specific. Laboratory tests demonstrated poorer specificities owing primarily to significant unresponsiveness in normal controls. Clinical otolith function tests, if conducted with precision, demonstrate greater ability than laboratory testing in discriminating normal controls from cases with unilateral complete compensated vestibular dysfunction.

Effect of practicing yoga on cervical vestibular evoked myogenic potential.

The present study attempted to determine the effect of practicing yoga on functioning of sacculo-collic pathway using cervical vestibular evoked myogenic potential (cVEMP). cVEMP was recorded from 40 participants (20 who practice yoga regularly and 20 who do not practice yoga regularly). The differences in amplitude of P1, N1, P1-N1 complex, asymmetry ratio and latencies of P1 and N1 of cVEMP were compared between both the groups. The results of the study showed that there was a significant increase (p<0.05) in the amplitude of P1, N1 and P1-N1 complex and a significant reduction in latency (p<0.05) for experimental group. The asymmetry ratio in individuals who practice yoga was significantly lower (Mean=6.73) compared to the control group (Mean=19.13). Multivariate regression analyses suggested that the number of years of yoga practice significantly predicted the amplitude of P1-N1 complex (β=0.70, p<0.01) and amplitude ratio (β=0.72, p<0.01). Thus, practicing yoga improves postural control and strengthens the muscles and vestibular system leading to enhanced cVEMP responses. The plastic changes in the vestibular system and increased muscular strength because of constant practicing of yoga could have led to changes in cVEMP responses. However, further studies on a larger group of individuals are essential for better clinical applicability of the results.

Auditory brainstem evoked responses and vestibular evoked myogenic potentials: potential biomarkers in Parkinson\u2019s disease

ObjectiveThe aim of this study was to investigate brainstem functions in Parkinson’s disease (PD) through studying auditory brainstem evoked responses (ABRs), and ocular and cervical vestibular evoked myogenic potentials (oVEMP and cVEMP) and to explore their relation with motor symptoms, if any.Study designFifteen individuals diagnosed as having idiopathic PD and 15 age-matched controls were included. The PD patients were evaluated using the Unified Parkinson’s Disease Rating Scale, the Hoehn and Yahr Scale, and the Schwab and England Scale. The subscores of major symptom were calculated, such as tremor, rigidity, bradykinesia, and axial signs. During medication ‘on’ states, PD patients and controls underwent pure-tone audiometry, speech audiometry, tympanometry, ABR, oVEMP, and cVEMP. The test findings in PD patients were grouped into ipsilateral and contralateral results in relation to the clinically more affected motor side and were compared with the age-matched controls.ResultsPD patients showed abnormal ABR wave morphology, prolonged absolute latencies of ABR wave V, and I–V interpeak latencies. Absent responses were the evident abnormality seen in oVEMP. Prolonged latencies with reduced amplitudes were seen in cVEMP responses. The main motor features of PD (rigidity and bradykinesia) were correlated to the ABR and cVEMP responses contralateral to the clinically more affected side.ConclusionDysfunction at different levels of the brainstem was confirmed in patients with PD. The impairment of ABRs and VEMP responses is related to characteristic clinical asymmetry of PD and its cardinal motor features. ABRs and VEMPs could be used as potential electrophysiological biomarkers for PD.

Assessment the effect of noise on the sacculocolic pathway using vestibular evoked myogenic potential

ObjectiveThe aim of this study was to detect the effect of noise on the sacculocollic pathway using cervical vestibular evoked myogenic potential (c-VEMP) and to check the correlation between the hearing thresholds and the c-VEMP responses in noise-induced hearing loss (NIHL) patients.Patients and methodsThe study included 40 (80 ears) participants. Their ages ranged between 30 and 45 years. They were divided into two groups: 20 (40 ears) participants with NIHL presenting with bilateral notched audiogram at 4kHz, and 20 (40 ears) participants as a control group. All participants in the study were subjected to basic audiological evaluation and VEMP tests.ResultsAs the average pure-tone hearing threshold increased, the c-VEMP latencies prolonged and peak-to-peak amplitude reduced in NIHL patients. Of the 40 ears, c-VEMP was absent in 12 (30%) ears. The latencies prolonged and the peak-to-peak amplitude reduced in 16 (40%) ears. VEMP results were normal in 12 (30%) ears.ConclusionNoise can cause more damage to the vestibular system, especially the sacculocollic pathway.

Effects of Peripheral Vestibular Dysfunction on Dynamic Postural Stability Measured by the Functional Reach Test and Timed Up and Go Test.

To investigate the influence of vestibular function on dynamic postural stability assessed by the functional reach test (FRT) and the timed up and go test (TUG). Retrospective study. Tertiary referral center. The FRT and TUG were performed in 399 patients with dizziness. The effects of peripheral vestibular dysfunction assessed by the caloric test and cervical vestibular evoked myogenic potentials (cVEMPs) to air-conducted sound (500 Hz, tone burst) on the results of FRT and TUG were analyzed. Neither FRT nor TUG scores showed significant differences in relation to the results of the caloric test ( P > .3). The FRT scores in patients who showed abnormal cVEMP responses on both sides were significantly smaller than those in patients who showed normal cVEMP responses ( P < .01). The TUG scores in patients who showed abnormal cVEMP responses on both sides were significantly greater than those in patients who showed normal cVEMP responses ( P < .05). The vestibulo-spinal reflex mediated by the saccule and its afferents is one of the factors that influence the maintenance of dynamic postural stability as measured by FRT and TUG.