research article relative efficiency of cochlear hydrops...

Research ArticleRelative Efficiency of Cochlear Hydrops Analysis MaskingProcedure and Cervical Vestibular Evoked Myogenic Potential inIdentification of Menierersquos Disease

Niraj Kumar Singh Rahul Krishnamurthy and Priya Karimuddanahally Premkumar

All India Institute of Speech and Hearing Mysore 570006 India

Correspondence should be addressed to Niraj Kumar Singh niraj6gmailcom

Received 25 June 2014 Revised 10 December 2014 Accepted 4 February 2015

Academic Editor Neil Bhattacharyya

Copyright copy 2015 Niraj Kumar Singh et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

Cervical vestibular evoked myogenic potential (cVEMP) and cochlear hydrops analysis masking procedure (CHAMP) haveboth shown sensitivity in identifying Menierersquos disease However none of the previous reports have compared the two tests fortheir relative efficacy in identifying Menierersquos disease Hence the present study aimed to compare the efficiency of cVEMP andCHAMP in evaluating Menierersquos disease The study included 58 individuals with unilateral definite Menierersquos disease and an equalnumber of age and gender matched healthy individuals cVEMP corresponding to 500Hz tone burst was recorded from ipsilateralsternocleidomastoidmuscle and CHAMPwas acquired from the conventional electrode sites for single channel auditory brainstemresponse recording using a default protocol of the Biologic Navigator Pro evoked potential system Both cVEMP and CHAMPshowed statistically significant differences between the groups (119875 lt 005) The receiver operating curves revealed 100 sensitivityand specificity for CHAMP as against 707 sensitivity and 100 specificity for cVEMP in identifyingMenierersquos diseaseThereforeCHAMP appears to be the test of choice provided the degree of hearing loss does not exceed a moderate degree cVEMP could beused for all degrees of hearing losses but with slight constraint on the sensitivity

1 Introduction

Menierersquos disease is a progressive idiopathic disorder of theinner ear which may result in degeneration of cochlearand vestibular hair cells It was first described by ProsperMeniere in 1861 and since then it has been noted as oneof the most common disorders of the vestibular system[1] It is characterized by the symptom triad of fluctuatingsensorineural hearing loss tinnitus and vertigo [2]Theothersymptoms include aural fullness nausea and vomiting [3]

The cause of Menierersquos disease is a source of curiosityand still remains controversial Trauma [4] viral vestibularganglionitis [5] and genetic predisposition [6] are amongthe most popular theories explaining the cause of Menierersquosdisease Other researchers suspect pathologies of the striavascularis to be responsible for the symptom complex inMenierersquos disease [7] Still others believe it to be a possibleautoimmune disorder [8] Irrespective of the beliefs regard-ing the causative factors the etiology of Menierersquos symptoms

has been shown to be an abnormal increase in endolymphvolumes in the inner ear [9ndash12]

The disagreement among the scholars regarding a defini-tive causative factor for Menierersquos disease adds up to thecomplex nature of the disease and increases the challengesposed upon clinicians towards its accurate identificationThis in addition to the high prevalence has probably ledto the trial of several tests for identifying Menierersquos diseaseever since its identificationThese include pure-tone audiom-etry immittance posturography glycerol test and electro-cochleography (ECochG)The sensitivity of these tests rangesfrom 37 to 61 whereas the specificity ranges from 51 to89 with most falling below 65 except posturography at89 [13 14] Lower sensitivity and specificity than desiredmake the above mentioned tests erratic for diagnosis thusmaking the administration of appropriate diagnostic tools achallenging task This has resulted in continued explorationof new tests for diagnosing Menierersquos disease More recently

Hindawi Publishing CorporationAdvances in OtolaryngologyVolume 2015 Article ID 978161 11 pageshttpdxdoiorg1011552015978161

2 Advances in Otolaryngology

cervical vestibular evoked myogenic potentials [15 16] andcochlear hydrops analysis masking procedure [17] have beenreported as promising tests for the identification of Menierersquosdisease induced changes in the audiovestibular periphery

Cervical vestibular evoked myogenic potential (cVEMP)is a test for evaluating the functional integrity of the saccule[18] This sound-induced potential is produced along thesacculocolic reflex pathway [18ndash20]The sound-induced elec-trical impulses which predominantly originate in the sacculewith some contributions from utricle and the semicircularcanal move along the vestibular apparatus through theinferior vestibular nerve and reach the sternocleidomastoid(SCM) muscle via the vestibulospinal tract [18ndash20] Therecorded response from the sternocleidomastoid muscle isa biphasic potential consisting of both positive and negativewaves where the positive wave is termed as P13 or P1and the negative one as N23 or N1 [18] cVEMP has beenfound to be useful in the identification of several vestibularpathologies including Menierersquos disease Findings such asreduced amplitude [21ndash27] and increased asymmetry ratio[25 28] of cVEMP have been reported in individuals withMenierersquos disease

The endolymphatic hydrops the most widely acceptedetiologic factor behind Menierersquos disease has been reportedto alter the stiffness properties of the basilar membrane andincreased fluid column height which is believed to causeincreased propagation speed of the travelling wave withinthe cochlea [29 30] Based on these unique changes inthe inner ear dynamics a noninvasive procedure known ascochlear hydrops analysis masking procedure (CHAMP) wasintroduced as a clinical tool to differentiate Menierersquos diseasefrom other vestibular pathologies [17] CHAMP assessesthe cochlear properties especially of the basilar membraneby using the principle of latency changes in ABR to clickstimuli caused by the presence of progressively reduced cut-off frequency of high-pass masking noiseThe undermaskingcaused by presence of Menierersquos disease results in a muchlesser difference inwaveV latency ofABRbetween unmasked(response to click alone) and masked (response to clicks inthe presence of high-pass masking with cut-off at 500Hz)conditions of responses [17]

CHAMP and cVEMP have both been extensivelyexplored and largely reported to be useful in identifyingMenierersquos disease The sensitivity of cVEMP in identifyingMenierersquos disease has been reported to range from 53 to94 [24 31] In terms of CHAMP Don et al reported 100sensitivity and specificity in identifying Menierersquos disease[17] However some of the other studies have questionedthese findings by reporting significantly lower sensitivityand specificity values [32 33] While de Valck et al reported31 sensitivity and 28 specificity Kingma and Wit showed32 sensitivity using the standard criteria of lt03ms latencydifference between click alone and click + 500Hz high-passmasking noise [31 32] Thus there appears to be a wide rangeof sensitivity and specificity values for both the potentialsThis indicates a need for continued exploration of thesetests in order to establish the usefulness or lack of it in thediagnosis of Menierersquos disease using these tests Furtherthese studies have been conducted at different places using

variable protocols and subjects Therefore the sensitivity andspecificity values for the two potentials cannot be compareddirectly There is also a dearth of studies comparing theseprocedures on the same set of individuals for examiningtheir relative efficacy in identifying Menierersquos diseaseTherefore the present study is aimed at comparing cVEMPand CHAMP for evaluating their efficiency in identifyingMenierersquos disease on the same group of individuals

2 Method

21 Participants The present study was conducted in accor-dance with the declaration ofHelsinki [34]The study used 58participants (30 males and 28 females) in the age range of 20to 50 years (mean age = 352 years standard deviation = 46)diagnosed with unilateral definite Menierersquos disease as par-ticipants of the clinical group Diagnosis of definite Menierersquosdisease was based on the criteria laid out by the Committeeon Hearing and Equilibrium of the American Academy ofOtolaryngology-Head and Neck Surgery [35] As per thesecriteria the diagnosis of definiteMenierersquos disease requires anindividual to experience two or more definitive spontaneousepisodes of vertigo lasting over 20 minutes documentedhearing loss using audiometric procedures on at least oneoccasion tinnitus or aural fullness in the affected ear withother causes of such precipitations ruled out The controlgroup consisted of 58 healthy individuals (30 males and 28females) in the age range of 20 to 50 years (mean age = 352years standard deviation = 46) with normal audiovestibularsystemwhich was ascertained by normal results on pure-toneaudiometry (hearing thresholds within 15 dBHL for bothair- and bone-conduction modes) type ldquoArdquo tympanogramwith acoustic reflex threshold within 100 dBHL at octavefrequencies from 500 to 2000Hz presence of otoacousticemissions and indication of no retrocochlear pathology onauditory brainstem responses

22 Procedure Biologic Navigator Pro (version 700) evokedpotential system (Illinois USA) was used for recordingCHAMP and cVEMP responses Both the evaluations werecarried out in acoustically treated single room suites withambient noise levels meeting the requirements of ANSIstandards [36]

221 Recording of Cervical Vestibular EvokedMyogenic Poten-tials For the purpose of recording cVEMP the participantswere seated on a straight back chairThe recording of cVEMPwas performed using the conventional electrode montageused previously [22 37ndash40] As per this the noninvertingelectrode was placed over the middle part of the body ofSCM muscle inverting at the sternoclavicular junction andthe ground on the forehead During the recording of theresponses the participants were instructed to rotate theirheads away from the ear of auditory stimulation in order toactivate the sternocleidomastoid muscle The muscle tensionwas maintained at a constant level within and betweensubjects by ensuring a constant target pointer on the shoulderresulting in about 60ndash70∘ head rotation from the midline

Advances in Otolaryngology 3

in a direction opposite to the ear of acoustic stimulationThis method has been shown to produce similar values ofvariability to the use of an LED device for visual feedbackand systems using electromyographic normalization [41] Ithas also been shown to produce similar or better test-retestreliability than the use of an LED device for visual feedback[42 43] Using the etymotic ER-3A insert earphones of theBiologic Navigator Pro evoked potential system alternatingpolarity 500Hz tone-bursts were presented at an intensity of125 dB SPL The stimuli were grated using 2ms risefall timeand 1ms plateau time as found optimum previously [39]Thestimuli were presented at a rate of 51 Hz Responses from 200stimuli were averaged to produce each waveform

222 Recording of Cochlear Hydrops Analysis Masking Pro-cedure CHAMP was recorded with the participants seatedin a comfortable position on a reclining chair The recordingof CHAMP involved placement of noninverting electrode onthe vertex inverting on the mastoid of the test ear and theground electrode on the mastoid of the opposite ear (nontestear) similar to those used in the previous studies [17 32 36]The default settings of the Biologic Navigator Pro evokedpotential system were used for recording CHAMP Rarefac-tion polarity 60 dB nHL clicks were presented through abroadband insert 580-BINSER at a repetition rate of 455sand averaged over 9200 stimuli Responses were obtainedfor click alone and click with different ipsilaterally presentedhigh-pass masking pink noises (81 dB SPL) with cut-off atoctave frequencies from 8000 to 500Hz (8000 4000 20001000 and 500Hz) An epoch of 16ms was used in orderto avoid un-ABR like responses that might arise beyond alatency of 16ms These responses were band-pass filteredbetween 01Hz and 3000Hz A total of 6 responses wererecorded one for click alone stimulus condition and theremaining five corresponding to click along with each of the5 high-pass masking noises The responses were recordedtwice for each stimulation condition in order to ensurereproducibility of the response

3 Results

The present study compared cVEMP and CHAMP in orderto arrive at the conclusion of a better test among the two foridentifying Menierersquos disease In order to fulfill the objectivesof the present study 58 individuals with Menierersquos diseasewere compared with an equal number of age and gendermatched healthy individuals on cVEMP and CHAMP

31 Cervical Vestibular Evoked Myogenic Potentials CervicalVEMP were obtained from both ears of 58 individualswith Menierersquos disease and same number of age and gen-der matched healthy individuals The obtained waveformswere analyzed morphologically for peak-to-peak amplitudeand asymmetry ratio Figure 1 shows representative cVEMPwaveforms recorded from an individual with unilateral defi-niteMenierersquos disease and an age and gendermatched healthyindividual

Descriptive statistics was done to obtain mean and stan-dard deviation of peak-to-peak amplitude and asymmetryratio of cVEMP in individuals with Menierersquos disease as wellas healthy individuals The lowest amplitudes were obtainedin the affected ears with Menierersquos disease followed by theirunaffected ears The individuals with Menierersquos disease alsoportrayed larger asymmetry ratios than their healthy coun-terparts The results of the descriptive statistics are shown inTable 1

The statistical significance of the above observations foramplitude was evaluated using one-way repeated measuresANOVA for ears with group as the between subject factor(mixed ANOVA) The results demonstrated a significantmain effect of ear [119865(1 114) = 6141 119875 lt 005] and group[119865(1 114) = 22035 119875 lt 005] but no significant interactionbetween ear and group [119865(1 114) = 3209 119875 gt 005]Although themixed ANOVA shows significant main effect ofear as well as group it does not shed light on ear differenceswithin each group and also group difference for each type ofear (Menierersquos affected ears and unaffected ears) In order toevaluate the existence of difference between the ears withineach group separate paired 119905-tests were administered for eachgroup and for identifying the presence of differences betweenthe groups for each type of ear independent samples 119905-testwere done Due to multiple 119905-tests appropriate Bonferronicorrections were incorporated for the levels of significanceThe results of paired 119905-test revealed significant differencebetween the ears in group of individuals with Menierersquosdisease [119905(57) = minus3106 119875 lt 0025] but not in the groups ofhealthy individuals [119905(57) = 0473 119875 gt 0025] The results ofindependent samples 119905-test revealed a significant differencebetween both Menierersquos affected ears and the matched earsof healthy individuals [119905(114) = minus4891 119875 lt 0025] as wellas the unaffected ears of individuals with Menierersquos diseaseand matched ears of healthy individuals [119905(114) = minus2523119875 lt 0025] These comparisons have been depicted inFigure 2 as box-plots An independent samples 119905-test was alsoadministered for asymmetry ratio comparison between thegroups The results revealed significant difference betweenthe groups [119905(114) = 8796 119875 lt 005] Figure 2 also shows thebox-plots of asymmetry ratio of cVEMP for both the groups

Thus the results of cVEMP were suggestive of signif-icantly smaller amplitude and larger asymmetry ratio inMenierersquos disease compared to healthy individuals Althoughthe participants were unilaterally affected with Menierersquosdisease the results revealed significantly smaller amplitudeof cVEMP even in the unaffected ears of individuals withMenierersquos disease when compared to age and gender matchedhealthy individuals group

32 Cochlear Hydrops Analysis Masking Procedure CHAMPresponses were obtained from all the 58 individuals withunilateral definite Menierersquos as well as their healthy controlsFigure 3 shows CHAMP waveforms obtained for click aloneand click with ipsilaterally presented high-pass masking pinknoise with cut-off at 500Hz

Descriptive statistics was carried out in order to obtainmean and standard deviation values for latency difference


Left ear-healthy individual Right ear-healthy individual

55048041034027020060 130minus80 minus10minus150 55048041034027020060 130minus80 minus10minus150

10000 (120583Vdiv) 10000 (120583Vdiv)P1

P1

N1

N1

(a)

Left ear-Menierersquos disease Right ear-Menierersquos disease

57049041033025017010 90minus70minus150 57049041033025017010 90minus70minus150

10000 (120583Vdiv) 10000 (120583Vdiv)

P1

P1

N1

N1

(b)

Figure 1 Representative cervical vestibular evoked myogenic potentials waveforms recorded from an individual with unilateral Menierersquosdisease (bottom panels) and an age and gender matched healthy individual (top panels) In this individual with Menierersquos disease right earwas the pathological ear The positivity is indicated upwards

Table 1 Mean and standard deviation for amplitude and asymmetry ratio of cervical vestibular evoked myogenic potentials and latencydifference of wave V between click alone and click with 500Hz high-pass masking pink noise in healthy individuals and individuals withMenierersquos disease

Population cVEMP CHAMPAmplitude (in 120583V) Asymmetry ratio (in ) Wave V latency difference (in ms)

Individuals withMenierersquos disease

Affected ear 10696 (7400) 4278 (2248) 014 (010)Unaffected ear 12492 (6096) 089 (011)

Healthy individuals Affected matched 15131 (6374) 1619 (490) 096 (017)Unaffected matched 15420 (6399) 093 (015)

Note ldquoaffected matchedrdquo and ldquounaffected matchedrdquo ears in healthy individuals are referred to the same side ears of the healthy individuals as that of individualswith Menierersquos disease that were affected and not affected by the disease respectively The values within the brackets represent standard deviation

between click alone condition and click along with ipsi-laterally presented high-pass masking pink noise with cut-off at 500Hz obtained from healthy individuals as well asindividuals with Menierersquos disease Lowest mean differencewas observed in the affected ears of individuals withMenierersquos

disease and largest difference between the stimulus condi-tions was obtained for ears of healthy individuals The resultsof descriptive statistics are shown in Table 1

The statistical significance of the above mentioned obser-vation was evaluated using one-way repeated measures


Healthy individualsMenierersquos disease

50000

40000

30000

20000

10000

000

Am

plitu

de (120583

V) lowast

lowast

lowast

(a)


Asy

mm

etry

ratio

()

10000

8000

6000

4000

2000

000

lowast

(b)

Figure 2 Box-plots for peak-to-peak amplitude (a) and asymmetry ratio (b) of cVEMP in healthy individuals and individuals withMenierersquosdisease star marks above the horizontal lines represent statistically significant comparisons

ANOVA for ears with group as the between subject factorfor CHAMP The results revealed a significant main effect ofear [119865(1 114) = 360724 119875 lt 005] and group [119865(1 114) =537135 119875 lt 005] There was also a significant interactionbetween ear and group [119865(1 114) = 420630 119875 lt 005] Thisnecessitated separate ear-wise analysis for groups and group-wise analysis for ears using one-way repeated measuresANOVA and MANOVA respectively One-way repeatedmeasures ANOVA for ears demonstrated a significant maineffect of ear in the group of individuals withMenierersquos disease[119865(1 57) = 1180603 119875 lt 005] however there was nosignificant main effect of ears in healthy individuals group[119865(1 57) = 0859 119875 gt 005] MANOVA was done for group-wise analysis which revealed a significant main effect ofgroup for comparison between affected ears of individualswith Menierersquos disease and matched ears of healthy subjects[119865(1 114) = 889161 119875 lt 005] but not for unaffected earsof individuals with Menierersquos disease and matched ears ofhealthy subjects [119865(1 114) = 2263 119875 gt 005]

Thus CHAMP revealed significantly smaller latencydifference of wave V between click alone and click with500Hz high-pass masking noise in affected ears of individualwith Menierersquos disease than their unaffected ears The latencydifference in affected ear with Menierersquos disease was alsosignificantly smaller than the ears of healthy individualsThere was no difference in the latency difference betweenthe ears of healthy individuals Figure 4 shows the box-plotsfor latency difference between the stimulus conditions (clickalone and click with high-pass masking noise with cut-offfrequency at 500Hz) in individuals with Menierersquos disease aswell as healthy individuals

33 Comparison between CHAMP and cVEMP Receiveroperating characteristic curves were obtained to examinesensitivity and specificity of CHAMP and cVEMP in iden-tifying Menierersquos disease (shown in Figure 5) Areas under

the curve for cVEMP and CHAMP were 0863 and 10respectively Asymmetry ratio of ge31 is considered forabnormality in cVEMP [21] and le03ms difference in waveV latency between click alone and click + 500Hz high-passmasking noise is as established for diagnosis of Menierersquosdisease using CHAMP [17 43] Using these values thesensitivity and specificity were found to be 655 and 100respectively for cVEMP whereas they are 931 and 100respectively for CHAMP Present studyrsquos data revealed opti-mum criterion points of ge29 asymmetry ratio of cVEMPand le048 for CHAMP for identifying Menierersquos disease Theuse of these values produced 707 and 100 sensitivity andspecificity respectively for cVEMP against 100 sensitivityand specificity for CHAMP

4 Discussion

Cervical VEMP and CHAMP were administered on all indi-viduals of both the groups of the study These two potentialshave been investigated separately in several previous studiesnonetheless reports on the same group of individuals to facil-itate the comparison of their relative efficiency in identifyingMenierersquos disease remained elusive until the present studyThe present study is the first step in this direction

41 Cervical Vestibular EvokedMyogenic Potentials inMeni-erersquos Disease The present study compared the findings ofcVEMP between Menierersquos disease and healthy individualsThe results revealed significantly smaller peak-to-peak ampli-tude of cVEMP in the Menierersquos group compared to thehealthy controls This is in agreement with those reportedpreviously in this regard [15 16] This might be attributed tothe changes observed at the vestibular periphery especiallythe saccule The histopathological studies in individuals withMenierersquos disease have revealed severe hydrops frequentlyresulting in the distortion of the saccule or even rupture of


20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V

VClick alone Click alone

Click + 500Hz high-pass maskingClick + 500Hz high-pass masking

V998400

V998400

V998400

V998400

(a)

Left ear-Menierersquos disease Right ear-Menierersquos disease20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone

Click + 500Hz high-pass masking

Click alone


(b)

Figure 3 Representative waveforms of cochlear hydrops analysis masking procedure showing the responses for click alone and click with500Hz high-pass masking noise in an individual with Menierersquos disease (bottom panels) and an age and gender matched healthy individual(top panels) In the individuals with Menierersquos disease right ear was the pathological ear

the saccular membrane [44ndash46] This distorted or rupturedsaccular membrane is likely to affect the mechanical energytransfer that vibrates the saccular macula and stimulates thesaccular hair cells This is therefore likely to result in reducedamplitude on the affected side of individuals with Menierersquosdisease

The results of the present study further showed signif-icantly smaller peak-to-peak amplitude of cVEMP in theunaffected (asymptomatic) ears of individuals with Menierersquosdisease than the ears of healthy controls Affected cVEMPresponses in the asymptomatic ears of individuals were alsoreported previously [47ndash49] The postmortem studies on

the temporal bones of individuals with Menierersquos diseasedemonstrated the presence of saccular hydrops in nearly 35of the asymptomatic ears [50] which further substantiatesthe findings of the present study This was called the ldquooccultsaccular hydropsrdquo in the previous reports [50] This meansthat there is a likelihood of binaural involvement in theseindividuals with a later onset of the symptoms in the unaf-fected ears This data (findings of present study and thosereported in literature in asymptomatic ears) correlates wellwith the data on binaural involvement in Menierersquos diseasewhich suggests binaural involvement in nearly 30 of theindividuals with Menierersquos disease Therefore a possibility of


Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast

Figure 4 Box-plots for wave V latency difference between click alone and click + 500Hz high-pass masking noise (CHAMP analysis) inhealthy individuals and individuals with Menierersquos disease Grey shaded boxes represent affected ear of individuals with Menierersquos diseaseand matched ear of healthy individuals Unshaded boxes represent unaffected ears of individuals with Menierersquos disease and matched ear ofhealthy individuals

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

Figure 5 Receiver operating characteristic curves for sensitivity and specificity of cervical vestibular myogenic potential (a) and cochlearhydrops masking procedure (b) in identifying Menierersquos disease

binaural involvement with a later time of onset in the asymp-tomatic ears might explain the findings of the present studyHowever this cannot be confirmed unless a longitudinalstudy on these individuals proves that occult saccular hydropsindeed was the reason for such a finding in the present study

The results of comparison between the groups for asym-metry ratio of cVEMP revealed significantly higher value ofasymmetry ratio in the group of individuals with Menierersquosdisease compared to the healthy individuals This is inagreement with those reported previously [15 16] However

there is slight disagreement of these findings with Rauchet al who reported no significant difference in asymmetryratio between the group of Menierersquos disease and healthycontrols [25] There was however an overall trend for greaterasymmetry within Menierersquos group compared to the controlsin Rauch et al [24] Thus the findings of the present studyseem to be in agreement with those reported by Rauch et al[25]

The finding of larger asymmetry ratio of cVEMP inMen-ierersquos disease might be attributed to the unilateral nature of


the pathology The previous research reports have shownMenierersquos disease to be mostly a unilateral pathology [26] cVEMP being an ipsilateral response with almost nocontribution from the contralateral side [18 21 30 51 52]would therefore be affected on one side but not on the otherside thereby producing larger asymmetry between the sidesin Menierersquos disease compared to the healthy controls

The saccule has been reported to be the second mostfrequent site of endolymphatic hydrops among the innerear structures possibly due to its close proximity to theendolymphatic duct [53] The mechanism for this increasein volume of endolymph is relatively unknown however it ishypothesized that osmotic or hydrostatic changes along withthe changes in permeability of ion channels are responsiblefor the symptoms in Menierersquos disease These abnormalitiescould cause an irregular flow of ions across the labyrinthinemembrane stimulating vestibular sensory cells In additionit is likely that the enlargement of the saccular duct pushesthe outer hair cell stereocilia into a less sensitive positionwhich could result in the deficits of mechanoelectrical trans-duction [6 54] While it is not certain how hydrops wouldmechanically affect the saccular macula it is possible thatthe organ could be affected by one or more of the abovepathological mechanisms Overall it is relatively clear thatthe abnormal cVEMP responses suggest an alteration in thenormal physiology of the saccule in patients with Menierersquosdisease [26]

42 CHAMP in Menierersquos Disease The results of CHAMPrevealed significantly smaller difference in latency of wave Vbetween click alone and click with 500Hz high-pass maskingpink noise inMenierersquos disease compared to healthy controlsThis is in agreement with some of the previous reports [1727 55] but in not in agreement with others [32 36] Thedissimilarity in findings might be attributed to the use ofdifferent population between the two sets of studies Thepresent study utilized only ldquodefinite Menierersquos diseaserdquo asopposed to no such criteria chosen for participantsrsquo selectionin these studies [32 36]

Smaller difference between unmasked and masked con-dition in Menierersquos disease compared to healthy controlscould be attributed to reduced efficiency of the masker as aresult of changes in the stiffness characteristics of the basilarmembrane precipitated by Menierersquos disease [17 55] Oneof the major characteristic changes induced by the presenceof Menierersquos disease is an increase in the travelling wavevelocity [56] The increased velocity of the travelling wavewould affect the properties of the basilar membrane butcannot affect the tonotopic organization along the basilarmembrane The increased velocity of the travelling waveis more likely to impact the low frequencies as they arerepresented towards the apical end on the basilar membrane(further away from generation point) When ABR latenciesare obtained by presenting clicks along with the high-passmasking noise in individuals with Menierersquos disease thealtered motion mechanics of the basilar membrane limits theability of low frequency noise to mask the activity in high

frequency [56] Hence in individuals with Menierersquos diseasewe can observe the phenomenon of undermasking in high-pass responses whereas the undermasking phenomenon isnot seen in normal individuals This would in turn resultin lesser latency difference between click alone and clickwith 500Hz high-pass masking noise condition in ears withMenierersquos disease than unaffected or normal ears

43 Comparison between cVEMP and CHAMP in IdentifyingMenierersquos Disease Thepresent study revealed higher sensitiv-ity of CHAMP than cVEMP in identifying Menierersquos diseaseTo the best of our knowledge this is the first attempt atcomparison between these two tests The finding of bettersensitivity of CHAMP than cVEMP in identifying Menierersquosdisease might be attributed to the extent of damage existingamong different inner ear structures by the endolymphatichydrops The cochlea has been reported to be the mostcommonly involved site followed by the saccule and theutricle [53] Since CHAMP is primarily a cochlea modulatedauditory nerve response [17 27 55] and cVEMP a saccularresponse [18] lower sensitivity of cVEMP in comparisonwith CHAMP is justifiable When a criterion of le048 fordifference between click alone and click with 500Hz high-pass masking noise was used for identification of Menierersquosdisease the results revealed 100 sensitivity and specificitysimilar to those reported previously although for slightlydifferent criteria [17 55]

The above comparison of sensitivity and specificity ofcVEMP and CHAMP appears to suggest that CHAMP is abetter test for evaluating inner ear functioning in Menierersquosdisease However an inherent constraint in the recording ofCHAMP arises from the use of only 60 dB nHL for clickintensity It is well known that the nHL thresholds obtainedusing the auditory brainstem response to clicks are 10 to20 dB higher than the behavioral auditory thresholds in HL[47 57] This would mean that for losses exceeding moderatedegree an auditory brainstem response to 60 dB nHL clickswould be absent since ABR thresholds for clicks have beenreported to be 10ndash20 dB higher than the actual behavioralthreshold Thus CHAMP would appear to be useful onlyup to a moderate degree of hearing loss On the contrarythe degree of sensorineural hearing loss does not impactthe VEMP responses in anyway [47] Therefore it would beuseful for evaluating patients of Menierersquos disease with anydegree of hearing loss In the present study all the participantshad moderate or lesser degrees of hearing losses (althoughit was not planned to select participants with only suchdegrees of hearing losses) and hence the results show a highersensitivity for CHAMP than cVEMP This might not be thecase if the degree of hearing loss in some subjects exceededmoderate degree

The results of the present study demonstrated signifi-cantly impaired cVEMP responses in the unaffected earsof individuals with Menierersquos disease However such anoccurrence was not observed for CHAMP which revealedno significant difference between the unaffected ears ofMenierersquos disease group and the ears of healthy controls Thepostmortem studies on the temporal bones of individuals


with Menierersquos disease have previously revealed saccularinvolvement in the largest proportion of individuals fol-lowed by cochlea utricle and the semicircular canals [45]This probably indicates that a saccular involvement withoutcochlear function compromise could be an early sign of onsetof Menierersquos disease in the asymptomatic ears Since cVEMPis mainly a saccule mediated response while CHAMP is acochlear mediated response the lack of significantly alteredCHAMP results in presence of significantly altered cVEMPresponses in the asymptomatic ears could be understoodThis further indicates that cVEMP could be a better toolto identify presymptomatic saccular hydrops and possiblypredict the onset of binaural involvement ofMenierersquos diseasein those who already have a unilateral pathology

5 Conclusion

Both cVEMP and CHAMP showed statistically significantdifferences between individuals with Menierersquos disease andhealthy individuals and therefore both the tests are sensitivein identifying Menierersquos disease induced changes in the innerear The receiver operating curves revealed 100 sensitivityand specificity for CHAMP as against 707 and 100 forcVEMP which appears to indicate that CHAMP is better testfor evaluation of Menierersquos disease than cVEMP HoweverCHAMP can only be recorded for losses not exceedingmoderate degree which limits its use to identifyingMenierersquosdisease with lesser degree of hearing losses only No suchlimitations are imposed by the degree of hearing loss oncVEMPThus CHAMP could be the test of choice for hearinglosses not exceeding moderate degree and cVEMP couldbe used for all degrees of hearing losses although withslight constraint on sensitivity Further cVEMP could alsoprove useful in identifying the occult Menierersquos disease in theasymptomatic ears of individuals with unilateral Menierersquosdisease

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

References

[1] L B Minor D A Schessel and J P Carey ldquoMenierersquos diseaserdquoCurrent Opinion in Neurology vol 17 no 1 pp 9ndash16 2004

[2] H F Schuknecht ldquoPathophysiology of Menierersquos diseaserdquo Oto-laryngologic Clinics of North America vol 8 no 2 pp 507ndash5141975

[3] K Yamakawa ldquoAbout the pathological alteration in a Menierersquospatientsrdquo Otorhinolaryngology Society Japan vol 4 pp 2310ndash2312 1938

[4] M M Paparella and F Mancini ldquoTrauma and Menierersquos syn-dromerdquo Laryngoscope vol 93 no 8 pp 1004ndash1012 1983

[5] R R Gacek and M R Gacek ldquoMenierersquos disease as a man-ifestation of vestibular ganglionitisrdquo The American Journal ofOtolaryngologyndashHead and Neck Medicine and Surgery vol 22no 4 pp 241ndash250 2001

[6] MM Paparella and H R Djalilian ldquoEtiology pathophysiologyof symptoms and pathogenesis of Menierersquos diseaserdquoOtolaryn-gologic Clinics of North America vol 35 no 3 pp 529ndash5452002

[7] H Masutani H Takahashi I Sando and H Sato ldquoVestibularaqueduct in Menierersquos disease and non-Menierersquos disease withendolymphatic eyedrops a computer aided volumetric studyrdquoAuris Nasus Larynx vol 18 no 4 pp 351ndash357 1991

[8] M J Ruckenstein ldquoImmunologic aspects of Menierersquos diseaserdquoThe American Journal of OtolaryngologymdashHead and Neck Med-icine and Surgery vol 20 no 3 pp 161ndash165 1999

[9] C S Hallpike and H Cairns ldquoObservations on the pathologyof Menieres syndromerdquo Proceedings of the Royal Society ofMedicine vol 31 pp 1317ndash1336 1938

[10] K C Horner ldquoOld theme and new reflections hearing impair-ment associated with endolymphatic hydropsrdquo HearingResearch vol 52 no 1 pp 147ndash156 1991

[11] D T Ries M Rickert and R S Schlauch ldquoThe peaked audio-metric configuration in Menierersquos disease disease relatedrdquoJournal of Speech Language and Hearing Research vol 42 no4 pp 829ndash843 1999

[12] R W Baloh and V Honrubia Clinical Neurophysiology ofVestibular System OxfordUniversity Press NewYorkNYUSA3rd edition 2001

[13] N Egami M Ushio T Yamasoba T Yamaguchi T Murofushiand S Iwasaki ldquoThe diagnostic value of vestibular evokedmyogenic potentials in patients with Menierersquos diseaserdquo Journalof Vestibular Research Equilibrium and Orientation vol 23 no4-5 pp 249ndash257 2013

[14] D Zack-Williams R M Angelo and Q Yue ldquoA comparison ofelectrocochleography and high-pass noise masking of auditorybrainstem response for diagnosis of Menierersquos diseaserdquo Interna-tional Journal of Audiology vol 51 no 10 pp 783ndash787 2012

[15] G Magliulo G Cuiuli M Gagliardi G Ciniglio-Appiani andR DrsquoAmico ldquoVestibular evoked myogenic potentials and glyc-erol testingrdquo Laryngoscope vol 114 no 2 pp 338ndash343 2004

[16] M-Y Lin F C A Timmer B S Oriel et al ldquoVestibular evokedmyogenic potentials (VEMP) can detect asymptomatic saccularhydropsrdquoThe Laryngoscope vol 116 no 6 pp 987ndash992 2006

[17] M Don B Kwong and C Tanaka ldquoA diagnostic test forMenierersquos disease and cochlear hydrops impaired high-passnoise masking of auditory brainstem responsesrdquo Otology andNeurotology vol 26 no 4 pp 711ndash722 2005

[18] J G Colebatch G M Halmagyi and N F Skuse ldquoMyogenicpotentials generated by a click-evoked vestibulocollic reflexrdquoJournal of Neurology Neurosurgery and Psychiatry vol 57 no2 pp 190ndash197 1994

[19] G Zhou and L C Cox ldquoVestibular evokedmyogenic potentialshistory and overviewrdquo The American Journal of Audiology vol13 no 2 pp 135ndash143 2004

[20] D Basta I Todt A Eisenschenk and A Ernst ldquoVestibularevokedmyogenic potentials induced by intraoperative electricalstimulation of the human inferior vestibular nerverdquo HearingResearch vol 204 no 1-2 pp 111ndash114 2005

[21] T Murofushi A Ochiai H Ozeki and S Iwasaki ldquoLaterality ofvestibular evoked myogenic potentialsrdquo International Journal ofAudiology vol 43 no 2 pp 66ndash68 2004

[22] M SWelgampola and J G Colebatch ldquoVestibulocollic reflexesnormal values and the effect of agerdquo Clinical Neurophysiologyvol 112 no 11 pp 1971ndash1979 2001


[23] M Ohki M Matsuzaki K Sugasawa and T Murofushi ldquoVes-tibular evoked myogenic potentials in ipsilateral delayed endo-lymphatic hydropsrdquo Oto-Rhino-Laryngology and Its RelatedSpecialties vol 64 no 6 pp 424ndash428 2002

[24] S D Rauch M B Silveira G Zhou et al ldquoVestibular evokedmyogenic potentials versus vestibular test battery in patientswith Menierersquos diseaserdquo Otology and Neurotology vol 25 no 6pp 981ndash986 2004

[25] S D Rauch G Zhou S G Kujawa J J Guinan and B SHerrmann ldquoVestibular evoked myogenic potentials showaltered tuning in patients with Menierersquos diseaserdquo Otology andNeurotology vol 25 no 3 pp 333ndash338 2004

[26] G Akkuzu B Akkuzu and L N Ozluoglu ldquoVestibular evokedmyogenic potentials in benign paroxysmal positional vertigoand Menierersquos diseaserdquo European Archives of Oto-Rhino-Laryn-gology vol 263 no 6 pp 510ndash517 2006

[27] S K Lee C I Cha T S Jung D C Park and S G Yeo ldquoAge-related differences in parameters of vestibular evokedmyogenicpotentialsrdquo Acta Oto-Laryngologica vol 128 no 1 pp 66ndash722008

[28] Y-H Young C-C Wu and C-H Wu ldquoAugmentation of ves-tibular evokedmyogenic potentials an indication for distendedsaccular hydropsrdquo Laryngoscope vol 112 no 3 pp 509ndash5122002

[29] J Tonnodorf ldquoThe mechanism of hearing loss in early casesof endolymphatichydropsrdquo Annals of Otology Rhinology andLaryngology vol 66 pp 766ndash784 1957

[30] G Flottorp ldquoCochlear nonlinearity in Menierersquos syndromerdquoHearing Research vol 2 no 3-4 pp 407ndash409 1980

[31] M W Li D Houlden and R D Tomlinson ldquoClick evokedEMG responses in sternocleidomastoidmuscles characteristicsin normal subjectsrdquo Journal of Vestibular Research Equilibriumand Orientation vol 9 no 5 pp 327ndash334 1999

[32] C F J de Valck G M E Claes F L Wuyts and P H van deHeyning ldquoLack of diagnostic value of high-pass noise maskingof auditory brainstem responses in Menierersquos diseaserdquo Otologyand Neurotology vol 28 no 5 pp 700ndash707 2007

[33] Declaration of Helsinki (1964) 2013 httpirbwayneedupoli-cies2-3 declaration of helsinkipdf

[34] ldquoCommittee on hearing and equilibrium guidelines for thediagnosis and evaluation of therapy in Menieres diseaserdquo Oto-laryngologymdashHead and Neck Surgery vol 113 no 3 pp 181ndash1851995

[35] American National Standards Institute American NationalStandards for Maximum Permissible Ambient Noise Levels forAudiometric Test Rooms ANSI S31 American National Stan-dards Institute New York NY USA 1999

[36] C M Kingma and H P Wit ldquoCochlear hydrops analysis mask-ing procedure results in patients with unilateral Menierersquosdiseaserdquo Otology and Neurotology vol 31 no 6 pp 1004ndash10082010

[37] N K Singh L Supreetha R S Kashyap and V Sahana ldquoChar-acterization of age-related changes in sacculocolic responseparameters assessed by cervical vestibular evoked myogenicpotentialsrdquo European Archives of Oto-Rhino-Laryngology vol271 no 7 pp 1869ndash1877 2014

[38] N K Singh S K Sinha R Govindaswamy and A KumarildquoAre cervical vestibular evoked myogenic potentials sensitiveto changes in the vestibular system associated with benignparoxysmal positional vertigordquoHearing Balance and Commu-nication vol 12 no 1 pp 20ndash26 2014

[39] N K Singh P Kumar T H Aparna and A Barman ldquoRisefalland plateau time optimization for cervical vestibular-evokedmyogenic potential elicited by short tone bursts of 500HzrdquoInternational Journal of Audiology vol 53 no 7 pp 490ndash4962014

[40] N K Singh and K Apeksha ldquoThe effect of risefall time of500Hz short tone bursts on cervical vestibular evoked myo-genic potentialrdquo Vestibular Research vol 24 pp 25ndash31 2014

[41] D L McCaslin G P Jacobson K Hatton A P Fowler and AP DeLong ldquoThe effects of amplitude normalization and EMGtargets on cVEMP interaural amplitude asymmetryrdquo Ear andHearing vol 34 no 4 pp 482ndash490 2013

[42] S Isaradisaikul D A Strong J M Moushey S A Gabbard SR Ackley and H A Jenkins ldquoReliability of vestibular evokedmyogenic potentials in healthy subjectsrdquo Otology and Neurotol-ogy vol 29 no 4 pp 542ndash544 2008

[43] B J Anoop and K N Singh ldquoTest-retest reliability of vestibularevoked myogenic potentials parametersrdquo in Student Research atAIISH (Articles Based on Dissertations Done at AIISH) vol 9pp 51ndash60 2011

[44] J R Lindsay R I Kohut and P A Sciarra ldquoMenierersquos diseasepathology and manifestationsrdquo Annals of Otology Rhinologyand Laryngology vol 76 no 1 pp 5ndash22 1967

[45] T Okuno and I Sando ldquoLocalization frequency and severity ofendolymphatic hydrops and the pathology of the labyrinthinemembrane in menierersquos diseaserdquo Annals of Otology Rhinologyand Laryngology vol 96 no 4 pp 438ndash445 1987

[46] F Salvinelli M Greco F H Trivelli and J R LinthicumldquoMenierersquos disease Histopathological changes a post mortemstudy on temporal bonesrdquo European Review for Medical andPharmacological Sciences vol 3 no 4 pp 189ndash193 1999

[47] S Ribeiro R K De Almeida H H Caovilla and M MGananca ldquoVestibular evoked myogenic potentials in theaffected and asymptomatic ears in the unilateral MenierersquosDiseaserdquoRevista Brasileira deOtorrinolaringologia vol 71 no 1pp 60ndash66 2005

[48] M Y Lin F C A Timmer B S Oriel et al ldquoVestibular evokedmyogenic potentials (VEMP) can detect asymptomatic saccularhydropsrdquo Laryngoscope vol 116 no 6 pp 987ndash992 2006

[49] H Fouly M E Minawi and T E Dessouki ldquoValue of VEMPin detecting saccular affection in the asymptomatic ear inthe patients with menierersquos disease rdquo Medical Journal of CarioUniversity vol 80 no 1 pp 397ndash403 2012

[50] K Tsuji L Velazquez-Villasenor S D Rauch R J Glynn CWall and S NMerchant ldquoTemporal bone studies of the humanperipheral vestibular system Menierersquos diseaserdquo Annals of Otol-ogy Rhinology amp Laryngology vol 181 pp 26ndash31 2000

[51] C Ferber-Viart R Duclaux B Colleaux and C DubreuilldquoMyogenic vestibular-evoked potentials in normal subjects acomparison between responses obtained from sternomastoidand trapezius musclesrdquo Acta Oto-Laryngologica vol 117 no 4pp 472ndash481 1997

[52] D D Robertson and D J Ireland ldquoVestibular evoked myogenicpotentialsrdquo Acta Otolaryngologica vol 24 no 1 pp 3ndash8 1995

[53] S N Merchant J C Adams and J B Nadol Jr ldquoPathophysi-ology of Menierersquos syndrome are symptoms caused by endo-lymphatic hydropsrdquo Otology amp Neurotology vol 26 no 1 pp74ndash81 2005

[54] A N Salt ldquoAcute endolymphatic hydrops generated by expo-sure of the ear to nontraumatic low-frequency tonesrdquo Journal ofthe Association for Research in Otolaryngology vol 5 no 2 pp203ndash214 2004


[55] M Don B Kwong and C Tanaka ldquoAn alternative diagnostictest for active Menierersquos disease and cochlear hydrops usinghigh-pass noise masked responses the complex amplituderatiordquo Audiology and Neurotology vol 12 no 6 pp 359ndash3702007

[56] G S Donaldson and R A Ruth ldquoDerived-band auditory brain-stem response estimates of traveling wave velocity in humansII Subjects with noise-induced hearing loss and Menierersquosdiseaserdquo Journal of Speech Language andHearing Research vol39 no 3 pp 534ndash545 1996

[57] Y-H Young T-WHuang and P-W Cheng ldquoVestibular evokedmyogenic potentials in delayed endolymphatic hydropsrdquoLaryn-goscope vol 112 no 9 pp 1623ndash1626 2002

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


MEDIATORSINFLAMMATION

of


Behavioural Neurology

EndocrinologyInternational Journal of



Disease Markers


BioMed Research International

OncologyJournal of



Oxidative Medicine and Cellular Longevity


PPAR Research

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

ObesityJournal of



Computational and Mathematical Methods in Medicine

OphthalmologyJournal of


Diabetes ResearchJournal of



Research and TreatmentAIDS


Gastroenterology Research and Practice


Parkinsonrsquos Disease

Evidence-Based Complementary and Alternative Medicine

Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom


cervical vestibular evoked myogenic potentials [15 16] andcochlear hydrops analysis masking procedure [17] have beenreported as promising tests for the identification of Menierersquosdisease induced changes in the audiovestibular periphery

Cervical vestibular evoked myogenic potential (cVEMP)is a test for evaluating the functional integrity of the saccule[18] This sound-induced potential is produced along thesacculocolic reflex pathway [18ndash20]The sound-induced elec-trical impulses which predominantly originate in the sacculewith some contributions from utricle and the semicircularcanal move along the vestibular apparatus through theinferior vestibular nerve and reach the sternocleidomastoid(SCM) muscle via the vestibulospinal tract [18ndash20] Therecorded response from the sternocleidomastoid muscle isa biphasic potential consisting of both positive and negativewaves where the positive wave is termed as P13 or P1and the negative one as N23 or N1 [18] cVEMP has beenfound to be useful in the identification of several vestibularpathologies including Menierersquos disease Findings such asreduced amplitude [21ndash27] and increased asymmetry ratio[25 28] of cVEMP have been reported in individuals withMenierersquos disease

The endolymphatic hydrops the most widely acceptedetiologic factor behind Menierersquos disease has been reportedto alter the stiffness properties of the basilar membrane andincreased fluid column height which is believed to causeincreased propagation speed of the travelling wave withinthe cochlea [29 30] Based on these unique changes inthe inner ear dynamics a noninvasive procedure known ascochlear hydrops analysis masking procedure (CHAMP) wasintroduced as a clinical tool to differentiate Menierersquos diseasefrom other vestibular pathologies [17] CHAMP assessesthe cochlear properties especially of the basilar membraneby using the principle of latency changes in ABR to clickstimuli caused by the presence of progressively reduced cut-off frequency of high-pass masking noiseThe undermaskingcaused by presence of Menierersquos disease results in a muchlesser difference inwaveV latency ofABRbetween unmasked(response to click alone) and masked (response to clicks inthe presence of high-pass masking with cut-off at 500Hz)conditions of responses [17]

CHAMP and cVEMP have both been extensivelyexplored and largely reported to be useful in identifyingMenierersquos disease The sensitivity of cVEMP in identifyingMenierersquos disease has been reported to range from 53 to94 [24 31] In terms of CHAMP Don et al reported 100sensitivity and specificity in identifying Menierersquos disease[17] However some of the other studies have questionedthese findings by reporting significantly lower sensitivityand specificity values [32 33] While de Valck et al reported31 sensitivity and 28 specificity Kingma and Wit showed32 sensitivity using the standard criteria of lt03ms latencydifference between click alone and click + 500Hz high-passmasking noise [31 32] Thus there appears to be a wide rangeof sensitivity and specificity values for both the potentialsThis indicates a need for continued exploration of thesetests in order to establish the usefulness or lack of it in thediagnosis of Menierersquos disease using these tests Furtherthese studies have been conducted at different places using

variable protocols and subjects Therefore the sensitivity andspecificity values for the two potentials cannot be compareddirectly There is also a dearth of studies comparing theseprocedures on the same set of individuals for examiningtheir relative efficacy in identifying Menierersquos diseaseTherefore the present study is aimed at comparing cVEMPand CHAMP for evaluating their efficiency in identifyingMenierersquos disease on the same group of individuals

2 Method

21 Participants The present study was conducted in accor-dance with the declaration ofHelsinki [34]The study used 58participants (30 males and 28 females) in the age range of 20to 50 years (mean age = 352 years standard deviation = 46)diagnosed with unilateral definite Menierersquos disease as par-ticipants of the clinical group Diagnosis of definite Menierersquosdisease was based on the criteria laid out by the Committeeon Hearing and Equilibrium of the American Academy ofOtolaryngology-Head and Neck Surgery [35] As per thesecriteria the diagnosis of definiteMenierersquos disease requires anindividual to experience two or more definitive spontaneousepisodes of vertigo lasting over 20 minutes documentedhearing loss using audiometric procedures on at least oneoccasion tinnitus or aural fullness in the affected ear withother causes of such precipitations ruled out The controlgroup consisted of 58 healthy individuals (30 males and 28females) in the age range of 20 to 50 years (mean age = 352years standard deviation = 46) with normal audiovestibularsystemwhich was ascertained by normal results on pure-toneaudiometry (hearing thresholds within 15 dBHL for bothair- and bone-conduction modes) type ldquoArdquo tympanogramwith acoustic reflex threshold within 100 dBHL at octavefrequencies from 500 to 2000Hz presence of otoacousticemissions and indication of no retrocochlear pathology onauditory brainstem responses

22 Procedure Biologic Navigator Pro (version 700) evokedpotential system (Illinois USA) was used for recordingCHAMP and cVEMP responses Both the evaluations werecarried out in acoustically treated single room suites withambient noise levels meeting the requirements of ANSIstandards [36]

221 Recording of Cervical Vestibular EvokedMyogenic Poten-tials For the purpose of recording cVEMP the participantswere seated on a straight back chairThe recording of cVEMPwas performed using the conventional electrode montageused previously [22 37ndash40] As per this the noninvertingelectrode was placed over the middle part of the body ofSCM muscle inverting at the sternoclavicular junction andthe ground on the forehead During the recording of theresponses the participants were instructed to rotate theirheads away from the ear of auditory stimulation in order toactivate the sternocleidomastoid muscle The muscle tensionwas maintained at a constant level within and betweensubjects by ensuring a constant target pointer on the shoulderresulting in about 60ndash70∘ head rotation from the midline




3 Results











10000 (120583Vdiv) 10000 (120583Vdiv)P1

P1

N1

N1

(a)



10000 (120583Vdiv) 10000 (120583Vdiv)

P1

P1

N1

N1

(b)













50000

40000

30000

20000

10000

000

Am

plitu

de (120583

V) lowast

lowast

lowast

(a)


Asy

mm

etry

ratio

()

10000

8000

6000

4000

2000

000

lowast

(b)






4 Discussion




20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V



V998400

V998400

V998400

V998400

(a)


15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone


Click alone


(b)






Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



















3 Results











10000 (120583Vdiv) 10000 (120583Vdiv)P1

P1

N1

N1

(a)



10000 (120583Vdiv) 10000 (120583Vdiv)

P1

P1

N1

N1

(b)













50000

40000

30000

20000

10000

000

Am

plitu

de (120583

V) lowast

lowast

lowast

(a)


Asy

mm

etry

ratio

()

10000

8000

6000

4000

2000

000

lowast

(b)






4 Discussion




20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V



V998400

V998400

V998400

V998400

(a)


15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone


Click alone


(b)






Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



















10000 (120583Vdiv) 10000 (120583Vdiv)P1

P1

N1

N1

(a)



10000 (120583Vdiv) 10000 (120583Vdiv)

P1

P1

N1

N1

(b)













50000

40000

30000

20000

10000

000

Am

plitu

de (120583

V) lowast

lowast

lowast

(a)


Asy

mm

etry

ratio

()

10000

8000

6000

4000

2000

000

lowast

(b)






4 Discussion




20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V



V998400

V998400

V998400

V998400

(a)


15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone


Click alone


(b)






Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of


















50000

40000

30000

20000

10000

000

Am

plitu

de (120583

V) lowast

lowast

lowast

(a)


Asy

mm

etry

ratio

()

10000

8000

6000

4000

2000

000

lowast

(b)






4 Discussion




20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V



V998400

V998400

V998400

V998400

(a)


15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone


Click alone


(b)






Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















20000 (nVdiv)20000 (nVdiv)

15030 50 70 90 130110minus10 1015030 50 70 90 130110minus10 10


V

V

V



V998400

V998400

V998400

V998400

(a)


15030 50 70 90 130110minus10 1030 15050 70 90 130110minus10 10

V

VV

V

Click alone


Click alone


(b)






Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of

















Late

ncy

diffe

renc

e (m

s)

140

120

100

080

060

040

020

000

141


lowast

lowast


100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(a)

100806040200

Sens

itivi

ty

10

08

06

04

02

00

1 minus specificity

(b)

















5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of



























5 Conclusion




References

































































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of


























































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of
















research article relative efficiency of cochlear hydrops...

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