Objective To observe the functional status of the otolith pathway in patients with unilateral idiopathic benign paroxysmal positional vertigo (BPPV) by combining air-conducted sound elicited cervical vestibular-evoked myogenic potential (ACS-cVEMP) and ocular vestibular-evoked myogenic potential (ACS-oVEMP). Methods One hundred and eighty patients with BPPV were recruited for conventional cVEMP and oVEMP tests. The abnormal rates of VEMPs were compared between BPPV patients and control participants. Results The abnormal rates of cVEMP and oVEMP in BPPV patients were 46.7% (84/180) and 57.2% (103/180) in affected ears, respectively, and 45.0% (81/180) and 56.7% (102/180) in unaffected ears, respectively; both were significantly higher than the abnormal rates of cVEMP and oVEMP in normal control ears. Compared with normal subjects, the cVEMP response rate was lower in affected and unaffected ears in BPPV patients. The abnormal rates of cVEMP and oVEMP were 48.1% (76/158) and 57.6% (91/158) in patients with posterior semicircular canal BPPV, and 36.4% (8/22) and 54.5% (12/22) in lateral semicircular canal BPPV. There was no significant difference in VEMP abnormalities between posterior semicircular canal BPPV and lateral semicircular canal BPPV. Conclusion The prevalence of abnormal cVEMPs and oVEMPs in both affected and unaffected ears of patients with BPPV was significantly higher than that observed in the control group. The pathological mechanism of unilateral idiopathic BPPV may be associated with bilateral degeneration of otolith pathways.

Objective: Subjective Visual Vertical (SVV) and Subjective Visual Horizontal (SVH) values may reflect bilateral utricle asymmetry. Bilateral utricle static tension balance can be used to evaluate bilateral otolith lesions and otolith-related central neuropathy. Few studies have examined Virtual Reality (VR)-assisted SVV and SVH values at various head-tilt angles across age groups. The present study aimed to determine the effects of age on VR-assisted SVV and SVH values at different head-tilt angles. Methods: We divided 180 healthy subjects into 6 age groups (n = 30 in each group). VR-assisted SVV and SVH measurements were performed at 9 head-tilt angles (head held vertically, 0°; head tilted 30°, 45°, 60°, and 90° to the left/right) in the roll plane. Results: SVV and SVH values significantly differed with head-tilt angle (p < 0.05). No significant difference was detected in the SVH and SVV values between different age groups (p = 0.632 and p = 0.810, respectively), and no interaction between the age group and the head-tilt angle was found for the SVH and SVV values (p = 0.670 and p = 0.084, respectively). Conclusion: These results suggest that age may have little effect on VR-assisted SVV and SVH at different head-tilt angles. Therefore, VR-assisted SVV and SVH can be evaluated as an effective, fast, and simple way to evaluate utricle function. Level of Evidence: Level 4.

ObjectiveTo investigate the effects of acoustic stimulation intensity on ocular and cervical vestibular evoked myogenic potential (oVEMP and cVEMP) responses elicited by air-conducted sound (ACS) in healthy children.MethodsThirteen healthy children aged 4–10 years and 20 healthy adults aged 20-40 years with normal hearing and tympanometry were enrolled in this study. All subjects received oVEMP and cVEMP tests under different acoustic stimulation intensities (131, 126, 121, 116, 111 and 106 dB SPL). Mean n1 latency, p1 latency, interpeak latency, amplitude and response rate were investigated and analyzed.ResultsAs the acoustic stimulation intensity decreased, for oVEMP, the response rate of children decreased from 100% (131, 126 and 121 dB SPL) to 57.69% (116 dB SPL), 26.92% (111 dB SPL) and 11.54% (106 dB SPL). The response rate of adults decreased from 100% (131 and 126 dB SPL) to 95% (121 dB SPL), 55% (116 dB SPL), 12.5% (111 dB SPL) and 2.5% (106 dB SPL). There were lower n1 latency, p1 latency and higher amplitude in children when comparing by acoustic stimulation intensities (p < 0.05). Regarding cVEMP, the response rate of children decreased from 100% (131, 126 and 121 dB SPL) to 88.46% (116 dB SPL), 53.85% (111 dB SPL) and 26.92% (106 dB SPL). The response rate of adults decreased from 100% (131 and 126 dB SPL) to 95% (121 dB SPL), 85% (116 dB SPL), 37.5% (111 dB SPL) and 7.5% (106 dB SPL). A statistically significant difference was found in amplitude at different acoustic stimulation intensities in both children and adults (p < 0.05). When stimulated by 131 dB SPL acoustic stimulation, there were lower n1 latency, p1 latency and higher amplitude in children in oVEMP and cVEMP compared with adults (p < 0.05).ConclusionThe response rate and amplitude of oVEMP and cVEMP in children and adults presented significant differences with a decrease in acoustic stimulation intensity. In this study, using 121 dB SPL for children and 126 dB SPL for adults during VEMP test could be regarded as safer stimulation intensities and thus reduced sound exposure.

Objectives: Although the cause of Meniere’s disease (MD) is not fully understood, endolymphatic hydrops is widely believed to be responsible for MD. Previous studies have used Air-Conducted Sound (ACS)-induced Vestibular Evoked Myogenic Potentials (VEMPs) to evaluate otolithic function in patients with MD. However, the use of Galvanic Vestibular Stimulation-VEMPs (GVS-VEMPs) with other vestibular tests in MD has been rare. This study aimed to explore the application of galvanic VEMPs in assessing MD. Methods: Normal individuals and patients with unilateral definite MD were included in this retrospective study. All participants underwent pure tone audiometry. Ocular and cervical VEMPs induced by GVS, and ACS were recorded. The characteristic parameters of VEMPs (n1 latency, p1 latency, amplitude, and AR) were analyzed. Results: The provocation rates of GVS-VEMPs did not differ between MD patients and control individuals. Compared with ACS, GVS could evoke potentials with longer latencies. MD patients presented GVS-VEMPs with lower amplitudes and ACS-cVEMP with shorter latencies and had a higher response rate in GVS-oVEMP. However, no differences or correlations were found in the characteristic parameters of GVS-VEMPs among the different stages of MD. Conclusions: GVS is as effective as ACS for inducing VEMP, and GVS-VEMP recording can detect retrolabyrinthine degeneration in MD. Further research is needed to assess the utility of GVS-VEMP in the evaluation of MD severity. Level of evidence: Level 4.

Objectives: This study aimed to determine vestibular involvement in patients with auditory neuropathy (AN) using ocular vestibular evoked myogenic potential (oVEMP), cervical vestibular evoked myogenic potential (cVEMP), caloric tests, video Head Impulse Tests (vHIT), and Suppression Head Impulse Paradigm (SHIMP) tests. Methods: Twenty-two patients with AN (study group) and 50 age-and-gender-matched healthy subjects (control group) were enrolled. All patients underwent air-conducted sound oVEMP and cVEMP tests. In the study group, 20 patients underwent a caloric test, 10 patients underwent a video Head Impulse Test (vHIT), and nine patients underwent the Suppression Head Impulse Paradigm (SHIMP) test. Results: Significant differences in VEMP abnormalities were found between the two groups. Most AN patients showed no VEMP response, while only a few patients showed VEMP responses with normal parameters. Some AN patients presented abnormal VEMP parameters, including thresholds, latencies, and amplitudes. The abnormal rate (including no response and abnormal parameters) was 91% in the cVEMP test and 86% in the oVEMP test. No significant difference was found between oVEMP and cVEMP abnormalities. AN patients exhibited a 70% abnormal rate in the caloric test. Most AN patients showed normal VOR gains. Most patients showed no overt corrective saccades in vHIT, and exhibited normal anticompensatory saccades in the SHIMP test. Conclusion: Many AN patients experience vestibular dysfunction, which may be detected by using a vestibular functional test battery. Significance: VEMP abnormalities might reflect the status and degree of vestibular involvement in AN. (C) 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

目的 分析对正常人视频头脉冲试验结果,建立本研究中心的正常值参考范围.方法 51例正常受检者(年龄31.24±9.96岁)佩戴装有高频摄像镜头的眼镜分别记录正坐位、向右转40°～45°、向左转40°～45°三个位置上甩头时眼球及头部的运动,测试各个半规管的前庭眼动反射增益值及补偿性扫视个数,评估三个共轭平面上的六个半规管的功能.结果 左侧水平半规管、右侧水平半规管的前庭眼动反射速度增益值分别为0.80±0.26、0.98±0.30;左上半规管、右后半规管、左后半规管、右上半规管四个垂直半规管的平均增益分别为0.80±0.19、0.73±0.18、0.93±0.20、0.73±0.22;所有半规管出现补偿性扫视的个数范围为0～4个.结论 本研究获得了各个半规管前庭眼动反射速度增益值及补偿性扫视个数正常值范围,对于前庭功能异常者检查结果的判定有重要的参考价值.

听神经病是一种以双耳中度低频感音神经耳聋为临床症状,但ABR反应严重异常、耳声发射正常的病症.其相关的前庭功能检测的报道与关注在学术界仍较少,本文旨对听神经病所伴有的前庭功能异常进行文献回顾,从前庭生理学及与其相关的前庭功能检测手段进行总结和概述.期望为听神经病患者的诊治与前庭功能评估提供参考.

目的 探讨听神经病(auditory neuropathy,AN)患者的前庭功能状况.方法 检测10例(20耳)听神经病患者(听神经病组)的颈肌前庭诱发肌源性电位(cervical vestibular evoked myogenic potential,cVEMP)、眼肌前庭诱发肌源性电位(ocular vestibular evoked myogenic potential,oVEMP)及前庭双温试验(caloric test),并与年龄、性别相匹配的50例(100耳)正常人(对照组)比较,分析听神经病患者外周前庭功能.结果 AN组oVEMP的引出率为35.0％(7/20),cVEMP的引出率为25.0％(5/20),明显低于对照组[93.0％(93/100)和97.0％(97/100)](P＜0.01).AN组oVEMP振幅(3.05±1.47μV)低于对照组(7.04±4.31 μV) (P＜0.01),阈值(125.28±7.32dBSPL)高于对照组(119.17±4.93dBSPL)(P＜0.05),P1潜伏期(15.94±0.67ms)、N1潜伏期(10.97±1.97 ms)均较对照组(分别为14.71±1.26和10.27±0.73ms)延长(P＜0.05);cVEMP振幅(101.15±14.39 μV)较对照组(244.12±143.43μV)降低(P＜0.01),N1-P1波间期(5.56±1.60 ms)较对照组(7.25±1.59 ms)缩短(P＜0.05).听神经病组中8例行双温试验,5例为单侧半规管功能减弱(CP＞25％),异常率为62.50％(5/8).除1例患者有轻微头晕,其他患者均无头晕、眩晕或行走不稳等前庭功能障碍表现.结论 听神经病患者在听觉受损的同时常伴有潜在的前庭功能异常,主要表现为前庭诱发肌源性电位消失或阈值升高、振幅降低、潜伏期延长以及双温试验异常等.

Objective: To investigate the relationship between hearing loss and vestibular dysfunction in patients with sudden sensorineural hearing loss (SSHL).Methods: Clinical data including the symptom of vertigo of 149 SSHL patients were investigated retrospectively. Pure tone audiometry, ocular vestibular-evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP) evoked by air-conducted sound (ACS), and caloric test were employed for cochlear and vestibular function assessment. The relationship between hearing level and vestibular dysfunction was analyzed.Results: The pure tone averages (PTAs) (mean +/- SD) of SSHL patients with and without vertigo were 88.81 +/- 21.74 dB HL and 72.49 +/- 21.88 dB HL (Z = -4.411, p = 0.000), respectively. The PTAs of SSHL patients with abnormal and normal caloric test were 84.71 +/- 22.54 dB HL and 70.41 +/- 24.07 dB HL (t = -2.665, p = 0.009), respectively. Conversely, vertigo and abnormal caloric results also happened more frequently in patients with profound hearing loss. However, no consistent tendency could be found among vestibular evoked myogenic potentials (VEMPs) responses or hearing loss.Conclusions: SSHL patients with vertigo or abnormal caloric test displayed worse hearing loss; and vice versa, vertigo and abnormal caloric results happened more frequently in SSHL patients with profound hearing loss.

Objective: This study aimed to define the characteristics and use of ocular and cervical vestibular evoked myogenic potentials for evaluating paediatric cochlear implant candidates.Methods: Ocular and cervical vestibular evoked myogenic potentials of 34 paediatric cochlear implant candidates were analysed. All patients also underwent a routine audiological examination, including computed tomography.Results: In all, 27 patients with normal inner-ear structures had absent or impaired vestibular evoked myogenic potential responses. In paediatric candidates with inner-ear malformations, ocular and cervical vestibular evoked myogenic potentials had lower thresholds and higher amplitudes. Vestibular evoked myogenic potential responses in this cohort were classified into three groups. There was significant concordance between vestibular evoked myogenic potentials and temporal bone computed tomography findings.Conclusion: Ocular and cervical vestibular evoked myogenic potential waveforms were different in paediatric candidates with normal and abnormal inner-ear structures. Therefore, vestibular evoked myogenic potential responses can indicate temporal bone structure.

Objective: To observe the otolithic function in sudden sensorineural hearing loss (SSHL) patients in different age groups by using vestibular evoked myogenic potentials (VEMPs). Methods: One hundred and seventy unilateral SSHL patients were divided into 5 age groups. The 170 affected ears belonged to study group. The opposite healthy ears of 170 patients and 138 normal ears of 69 age and sex-matched normal people at different ages were set as control groups. Ocular VEMP (oVEMP) and cervical VEMP (cVEMP) both evoked by air-conducted sound (ACS) were employed for vestibular otolithic function assessment. Results: The response rates of cVEMP and oVEMP were lower and abnormal rates were higher in affected ears of SSHL patients compared to the opposite healthy ears and normal control ears in all age groups, except patients over 60 years. The response rates of VEMPs significantly declined with increasing age, not only in normal control ears, but also in affected and healthy ears of SSHL patients. But, the abnormal rates of VEMPs showed no significant difference in affected ears at different ages. Conclusions: Dysfunction of vestibular otolithic organs in SSHL patients presented respective features at different ages. It is necessary to consider the age when the clinicians determine the otolithic condition of patients based on the VEMPs.

Objective: This study sought to define the profile of ocular and cervical vestibular-evoked myogenic potential (oVEMP and cVEMP) in children with profound sensorineural hearing loss (PSHL).Methods: The ACS-evoked oVEMPs and cVEMPs of 43 children with PSHL and 20 healthy children were investigated. The response rates, thresholds, amplitudes, P1 and N1 latencies, and interpeak latencies of VEMPs were analyzed. Each patient's medical record was summarized and classified.Results: The response rates of oVEMP and cVEMP in patients with PSHL were 58.1% and 61.9% respectively, which were significantly less than those in healthy children (both were 100%). In the children patients whose oVEMP or cVEMP could still be elicited, significant elevated thresholds and decreased amplitudes in VEMPs could be observed (p < 0.05). However, in the summary of the medical records of all the 43 patients, it was showed that neither the patients and their parents nor the doctors noticed the balance problem and the loss of otolithic function.Conclusions: The otolithic dysfunction, which could be easily ignored in children with PSHL, could be observed in VEMPs. In the process of diagnosis and treatment of PSHL, the vestibular function should obtain enough attention. VEMPs have special value in observation of the hidden loss of otolithic function, and could be an important vestibular assessment method for children with PSHL. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

OBJECTIVE To observe waveform difference among cervical vestibular evoked myogenic potentials (cVEMP) elicited with different types of air conducted sound in normal young Chinese subjects. METHOD Twenty adult volunteers (40 ears) were recruited as research subjects including 10 males and 10 females aged between 19 and 30.500 Hz Tone Burst, 1000 Hz Tone Burst and Click were employed as stimulus for conventional air conducted sound-cVEMP (ACS-cVEMP) examinations in bilateral ears of each subject. The response rate, threshold, P1 latency, N1 latency, P1-N1 latency interval, amplitude and inter-aural asymmetry were recorded and compared among groups. RESULT The response rate was 97.5% in 500Hz Tone Burst (39/40), 87.5% in 1 000Hz Tone Burst (35/40)and 67.5% in Click (27/40), There were no statistically significant difference between 500Hz Tone Burst and 1000Hz Tone Burst (P > 0.05) but there were statistically significant difference between click and the other groups (P < 0.05). We collected the waveform parameters (the threshold, P1 latency, N1 latency, P1-N1 latency interval, amplitude) which had statistically significant difference between 500 Hz Tone Burst and the other groups (P < 0.05). The inter-aural asymmetrys had no statistically significant differents among groups. CONCLUSION The response rate and parameter could be affected by different types of air conducted sound in normal young Chinese subjects. 500 Hz Tone Burst was the best stimulus of type what we have known.

OBJECTIVE:To observe waveform differences among ocular vestibular evoked myogenic potentials (ACS-oVEMP) elicited by different types of air conducted sound in normal young Chinese subjects.METHOD:Twenty-two adult volunteers (44 ears) were recruited as research subjects including 12 males and 10 females aged between 18 and 35. Five hundred Hz tone burst, 125 Hz tone burst and click were employed as stimulus for conventional ACS-oVEMP examinations in bilateral ears of each subject. The response rate, threshold, n I latency, p I latency, n I-p I latency interval, amplitude and inter-aural asymmetry were recorded and compared among groups.RESULT:The response rate was 100% (44/44) in 500 Hz tone burst group, 40.9% (18/44) in 125 Hz tone burst group and 29.6% (12/44) in click group There were statistical significant differences between the 500 Hz tone burst group and the other groups (P < 0.05). Waveform amplitude was the largest in the 500 Hz tone burst group (7.3 +/- 5.5) muV than that in the 125 Hz tone burst group (3.8 +/- 1.5) muV and that in the click group (5.8 +/- 1.3) muV, which had statistically significant differences between the former and the later two groups (P < 0.05). Other waveform parameters presented similar differeces.CONCLUSION:ACS-oVEMP waveforms could be largely affected by different stimulus. 500 Hz tone burst was the best stimulus with highest response rate, biggest amplitude and therefore most easily recognizable waveform in ACS-oVEMP examination.

OBJECTIVE:To identify the aging effects on air-conducted sound (ACS) elicited ocular vestibular-evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP) in normal Chinese population.METHODS:Nighty-seven normal subjects (194 ears) were recruited for conventional ACS-oVEMP and ACS-cVEMP examinations. The candidates'age were 4-83 years old (Ave. ± SD, 45.7 ± 19.3), 41 male and 56 female, divided into 5 groups according to age. 500 Hz short tone burst was employed for examinations. Thresholds were identified and the parameters of the responses to 100dB nHL were calculated and compared among groups. SPSS 13.0 software was used to analyze the date.RESULTS:As the age growing, the response rate for oVEMP decreased. It was recorded 100% in both ≤ 10-year-old and 11-30-year-old groups, 84.00% in the 31-50-year-old group, 48.15% in the 51-70-year-old group and 15.00% in the > 70-year-old group; while that for cVEMP were 100% in both ≤ 10-year-old group and 11-30-year-old group, 82.00% in the 31-50-year-old group, 77.78% in the 51-70-year-old group and 45.00% in the > 70-year-old group. The thresholds elevated and the amplitudes decreased in both examinations with the age growing. However, latencies and latency-intervals of both oVEMP and cVEMP examinations displayed minor difference among groups except that nI latency of oVEMP prolonged with age growing.CONCLUSIONS:With the age growing, the otolithic end organ input pathways degenerate in normal subjects, as shown that ACS elicited oVEMP and cVEMP responsed less with higher threshold and smaller amplitude. The extremely low response rates of both VEMPs in the > 70-year-old group in this study indicates that VEMPs can only provide limited diagnostic information among very old people in clinical practice.

Objective: To define the profile of ocular and cervical vestibular-evoked myogenic potentials (oVEMPs and cVEMPs) in children with cochlear implant (CI), we studied air-conducted sound (ACS)-evoked responses pre- and postoperatively.Methods: The ACS-evoked oVEMPs and cVEMPs of 31 children with cochlear implantation were investigated. Thresholds, amplitudes, P1 and N1 latencies, and interpeak latencies of VEMPs were measured and analyzed.Results: Before CI, the response rates of oVEMPs and cVEMPs were 71.0% and 67.7%, respectively. The oVEMPs and cVEMPs on the operated side disappeared after CI, which resulted in a decrease in response rates, whether the device was switched on (12.9% and 32. 0%) or off (19.2% and 34.8%). In the case when VEMPs could be elicited on the operated side after CI, the parameters of waveforms showed abnormal changes, including threshold elevation (maximum of 8.34-dB SPL in oVEMP and 8.75-dB SPL in cVEMP) and amplitude decrease (maximum of 4.10 mu V in oVEMP and 191.82 mu V in cVEMP).Conclusions: Disappearance and impairment of VEMPs could be observed after CI, and the waveforms of oVEMP and cVEMP could reflect the degree of damage to the utricle and saccule caused by CI and other related factors.Significance: The oVEMPs and cVEMPs prove to be accurate methods to evaluate vestibular function in children with CI. (c) 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

OBJECTIVETo observe the effect of acoustic stimulus intensity on air-conducted sound elicited ocular vestibular- evoked myogenic potential (oVEMP) and cervical vestibular-evoked myogenic potential (cVEMP) in normal young Chinese subjects.METHODSThirty-five normal subjects aged 4-40 years (20.80∓8.89 years), including 16 males and 19 females, were recruited for conventional oVEMP and cVEMP examinations. The responses obtained from each side using 500 Hz tone bursts were divided into 6 groups according to different sound intensities (100, 95, 90, 85, 80 and 75dB nHL). The response rate and normal parameters of each stimulus intensity group were calculated.RESULTSAs the acoustic stimulus intensity decreased, the oVEMP response rate decreased from 100% in both 100 dB nHL and 95dB nHL groups to 97.14% (90 dB nHL), 54.29% (85 dB nHL), 14.29% (80 dB nHL), and 2.86% (75 dB nHL), and the response rate of cVEMP, 100% in both 100 dB nHL and 95dB nHL groups, was lowered to 97.14% (90 dB nHL), 84.29% (85 dB nHL), 38.57% (80 dB nHL) and 8.57% (75 dB nHL). The response rate and the parameters were comparable between 100 and 95 dB nHL groups.CONCLUSIONAs the acoustic stimulus intensity decreases, both oVEMP and cVEMP show decreased response rate and amplitude. For Chinese subjects under 40 years of age, we recommend 95dB nHL as the maximum initial stimulus intensity in VEMPs test.

Objective To explore the clinical characteristics of vestibular-evoked myogenic potentials(VEMPs)in patients with benign paroxysmal positional vertigo(BPPV).Methods We enrolled67 BPPV patients as the observation group and 19(38 ears)age-and gender-matched normal subjects as the normal control group. Both patients and normal subjects underwent conventional ocular-VEMP(oVEMP)and cervical-VEMP(cVEMP) tests in bilateral ears.The results were compared between the affected ears,the contralateral ears of the patients and the normal control ears.Results oVEMP was elicited in29 affected ears(43.3%),28 contralateral ears(41.8%) and 27 normal ears(71.1%).No significant difference was found in response rate between the affected ears and the contralateral ears(P0.05).However,significant difference could be found between the affected group(both affected ears and contralateral ears)and the normal group(P0.01).cVEMP could be elicited in42 affected ears(62.7%),41 contralateral ears(61.2%)and 32 normal ears(84.2%).There were no significant difference in response rate between the affected ears and the contralateral ears(P0.05);however,significant difference could be found between the affected group(both affected ears and contralateral ears)and the normal group(P0.05). The response rate of oVEMP was remarkably lower than that of cVEMP(P0.05).However,no significant difference was found in oVEMP or cVEMP parameters(threshold,N1 latency,P1 latency,or amplitude)among the groups(P 0.05).Conclusion The response rates of oVEMP and cVEMP in the affected and the contralateral ears in the affected groups are significantly lower than those in normal controls;low response rates are more likely to appear in oVEMP tests.The waveforms of oVEMP and cVEMP tend to remain normal in patients with BPPV.

OBJECTIVE:To observe the function of the otolithic end organs and their input pathways in sudden sensorineural hearing loss (SSHL) patients.METHODS:Forty cases of unilateral SSHL were enrolled as the observing group from May, 2011 to May, 2012. Thirty age- and gender-matched normal subjects were recruited as the control group. Both patients and normal subjects underwent conventional air-conducted ocular vestibular evoked myogenic potential (oVEMP) and cervical vestibular evoked myogenic potential (cVEMP) in bilateral ears. The results were compared between the affected ears, the contralateral ears and the normal controls.RESULTS:Overall, oVEMP was elicited in 16 affected ears (40.0%), 23 contralateral ears (57.5%) and 43 normal ears (71.7%). cVEMP could be elicited in 25 affected ears (62.5%), 30 contralateral ears (75.0%) and 49 normal ears (81.7%) respectively. Significant statistical significance could be found in the oVEMP response rate between the affected ears and the normal ears (χ(2) = 9.949, P = 0.002) and in the cVEMP response rate between the affected ears and the normal ears (χ(2) = 4.582, P = 0.032). Significant statistical difference could not be found in all oVEMP and cVEMP parameters (threshold, N1 latency, P1 latency, latency interval and amplitude) among groups (P > 0.05).CONCLUSIONS:The otolithic vestibular end organs and their input pathways could be damaged in SSHL patients. Such damages could be monitored objectively by cVEMP and oVEMP examinations.

OBJECTIVE:To identify the characteristics of the air-conducted ocular vestibular-evoked myogenic potential (oVEMP) in the young normal Chinese subjects.METHODS:Twenty five normal subjects were recruited for conventional examinations of oVEMP. The subjects were 19 - 45 years of age [(24.3 ± 5.6) years], 12 males and 13 females. 500 Hz air-conducted tone burst was employed for examination. The threshold of oVEMP in each ear was examined; patterns of these waves were observed and the normal ranges of the oVEMP waves responded to 100 dBnHL were calculated.RESULTS:All subjects were elicited with normal oVEMP N1-P1 waves in both ears. The response rate in these subjects was 100%. The threshold of oVEMP examination was (86.6 ± 3.6) dBnHL (x(-) ± s), latency N1 (10.1 ± 0.4) ms, latency P1 (14.7 ± 1.2) ms, interval N1-P1 (4.5 ± 1.0) ms, amplitude (7.9 ± 4.4) µV.CONCLUSIONS:Air-conducted oVEMP is a kind of vestibular-ocular reflex respond to intensive sound generated by otolithic vestibular end organs. It is stable in the young normal subjects with minor variabilities.