www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
ORIGINAL
ARTICLE
Use
of
remote
control
in
the
intraoperative
telemetry
of
cochlear
implant:
multicentric
study
夽
Liege
Franzini
Tanamati
a,
Maria
Valéria
Schmidt
Goffi-Gomez
c,∗,
Lilian
Ferreira
Muniz
b,
Paola
Angélica
Samuel
c,
Gislaine
Richter
Minhoto
Wiemes
d,
Daniele
Penna
Lima
e,
Sílvia
Badur
Curi
f,
Lucia
Cristina
Onuki
f,
Carla
Fortunato
Queiroz
d,
Ana
Karla
Bigois
Capistrano
e,
Adriane
Lima
Mortari
Moret
a,
Márcia
Yuri
Tsumura
Kimura
g,
Valeria
Oyanguren
h,
Herbert
Mauch
haUniversidadedeSãoPaulo(USP)---CampusBauru,Bauru,SP,Brazil bUniversidadeFederaldePernambuco(UFPE),Recife,PE,Brazil
cUniversidadedeSãoPaulo(USP),FaculdadedeMedicina,HospitaldasClínicas,SãoPaulo,SP,Brazil dUniversidadedoParaná(UFPR),FaculdadedeMedicina,HospitaldasClínicas,Curitiba,PR,Brazil eHospitaldoCorac¸ãodeNatal,Natal,RN,Brazil
fUniversidadedeCampinas(UNICAMP),FaculdadedeMedicina,HospitaldasClínicas,Campinas,SP,Brazil gPolitecSaúde---RepresentanteCochlearnoBrasil,SãoPaulo,SP,Brazil
hCochlearLatinAmerica,PanamaCity,Panama
Received20October2017;accepted9April2018 Availableonline18May2018
KEYWORDS Cochlearimplant; Impedance; Evokedpotential; Telemetry Abstract
Introduction:The conventional evaluationofneural telemetry andimpedance requiresthe useofthecomputercoupledtoaninterface,withsoftwarethatprovidesvisualizationofthe stimulusandresponse.Recently,aremotecontrol(CR220®)waslaunchedinthemarket,that allowstheperformanceofintraoperativetestswithminimalinstrumentation.
Objective:Toevaluatetheagreementoftheimpedancevaluesandneuraltelemetry thresh-olds,andthetimeofperformanceintheconventionalprocedureandbytheremotecontrol.
Methods:Multicentricprospectivecross-sectionalstudy.Intraoperativeevaluationsofcochlear implantscompatiblewiththeuseofCR220® wereincluded.Thetestswerecarriedoutinthe 22electrodestocomparethetimeofperformanceinthetwosituations.Theagreementof theneural telemetrythresholdvaluesobtained fromfiveelectrodeswas analyzed,andthe agreementofimpedancewasevaluated bythenumber ofelectrodeswithaltered valuesin eachprocedure.
夽 Pleasecitethisarticleas:TanamatiLF,Goffi-GomezMV,MunizLF,SamuelPA,WiemesGR,LimaDP,etal.Useofremotecontrolinthe intraoperativetelemetryofcochlearimplant:multicentricstudy.BrazJOtorhinolaryngol.2019;85:502---9.
∗Correspondingauthor.
E-mail:valeria.goffi@hc.fm.usp.br(M.V.Goffi-Gomez).
PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.
https://doi.org/10.1016/j.bjorl.2018.04.003
1808-8694/©2018Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen accessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).
Results:There were no significantdifference between the impedance values. There was a moderate tostrong correlationbetween the electrically-evoked compound action potential thresholds.ThemeantimetoperformtheproceduresusingtheCR220wassignificantlylower thanthatwiththeconventionalprocedure.
Conclusion: TheuseoftheCR220providedsuccessfulrecordsfor impedancetelemetry and automaticneuralresponsetelemetry.
© 2018 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/). PALAVRAS-CHAVE Implantecoclear; Impedâncias; Potencialevocado; Telemetria
Usodocontroleremotonatelemetriaintraoperatóriadoimplantecoclear:estudo
multicêntrico
Resumo
Introduc¸ão: Aavaliac¸ãoconvencionaldatelemetrianeuraledeimpedânciasimplicaousodo computador acoplado auma interface, osoftwarefornece oestímuloe avisualizac¸ãodas respostas. Recentemente, foi lanc¸ado um controleremoto (CR220®), que possibilitatestes intraoperatórioscominstrumentalmínimo.
Objetivo: Avaliara concordância dos valores das impedânciase doslimiares da telemetria neuraleotempodeexecuc¸ãonoprocedimentoconvencionalepelocontroleremoto.
Método: Estudoprospectivotransversalmulticêntrico.Foramincluídasasavaliac¸ões intraop-eratóriasde implantecoclearcompatívelcomouso doCR220®.Ostestes foramrealizados nos 22eletrodos paracomparar ostemposdeexecuc¸ãonasduassituac¸ões.Foianalisada a concordânciadosvaloresdolimiardatelemetrianeuralobtidosemcincoeletrodosea con-cordância dasimpedânciasfoi avaliadapelonúmerodeeletrodoscomvalores alteradosem cadaprocedimento.
Resultados: Nãohouve diferenc¸a significante entre asimpedâncias. Obteve-se moderada a forte correlac¸ãoentreoslimiaresdopotencialdeac¸ãocompostoeletricamenteevocado. O tempomédioparaosprocedimentoscomoCR220foisignificativamentemenordoquecomo procedimentoconvencional.
Conclusão:O uso do CR220 proporcionou registros bem-sucedidos para a telemetria de impedânciaeatelemetriaautomáticaderespostasneurais.
© 2018 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Publicado por Elsevier Editora Ltda. Este ´e um artigo Open Access sob uma licenc¸a CC BY (http:// creativecommons.org/licenses/by/4.0/).
Introduction
The use ofobjective datarecording duringthe
intraoper-ativeprocedure ispart oftheroutineof cochlearimplant
programs worldwide. Such data are useful for analyzing
deviceintegrity,determiningwhethertherearemeasurable neuralresponses,assistinginprognosticdetermination,
con-tributing to the choice of speech processor programming
parameters;theyalsoprovideanoptiontoevaluateauditory nerveresponsealterationsovertime.1---3
The most commonly used intraoperative procedures
are impedance telemetry and neural response telemetry.
Impedance telemetry measures the opposition to the
current flow, from the system characteristics, and its
measurement allows the evaluation of the implanted
system electronic integrity. High impedances can signify
brokenelectrodes,absenceofelectrode---tissuecontact,or
electrodes located outside the cochlea. Low impedances
may suggest electrodes in short-circuit. In any of these
situations,electrodes withimpaired impedances mustnot
beactivatedorusedtomeasuretheneuralresponse.4,5
Neural response telemetry (NRT) is a rapid,
noninva-siveand objectivemeasureof peripheralneural function.
Itis a measurederived from theelectrical stimulation of
theauditorynerveandtheobtained responsereflectsthe
electrically-evokedcompoundactionpotential(ECAP).The
responses have a relatively short latency, generally less
than0.5ms.Theyareevokedusingbiphasicpulsecurrents
and measured by an adjacent electrode that sends the
response to the cochlear implant (CI) speech processor.
The ECAP is characterized by a negative peak (N1)
fol-lowed by a positive peak (P2), and the amplitude of the
responsebetweenN1---P2increaseswithincreasingcurrent level.ThemainadvantageofmeasuringECAPovertheother
measures of evoked potentials is that it can be recorded
rapidly in CI users of any age, with no need for surface
electrodes or sedation or even for the child to remain
Typically, the tests are carried out by an experienced
audiologist using the specific external device, equipment
andsoftware.Recently,CochlearTMhasintroducedCR220® ,
a remoteassistant, capable of performing such
measure-ments that has the advantage that it does not require
other equipment besides the external device. In addition
to the audiologist, other professionals are also present
in the operating room: doctors, anesthesiologist, scrub
nurses,neurophysiologist,allwiththeirworkstations.
Some-timesthisdynamiccanhindercirculationintheroomand
compromisetheworkperformance.Theuseofaportable,
wirelessdevicethatallowsthesameprocedurestobe
car-ried out as in a larger workstation can be very useful in
optimizingthephysicalspace,aswellascontributingtothe bestmobilityaroundtheplace,whilemaintainingthesame qualityofresponses.7
Tavartkiladzeetal.8 havepreviouslystudied both
tech-nologiestomeasureintraoperativeECAPdataandconcluded
that there is a significant reduction in the time used to
measurethe ECAP thresholds withthe use of the remote
device(CR120®).Althoughthetestperformancetimewith theremoteassistantisshorter,itisnecessarytoknowifthe measuresbybothproceduresareequivalentandifthereare false-positiveorfalse-negativeresults,requiringtheuseof
thestandardsoftwareforadvancedECAPthreshold
assess-ment.
Considering the work dynamics of the professionals
involved in cochlear implant programs, this study aimed
to evaluate the percentage of the implanted population
thatexhibits arecordableneural responsefromboth
pro-cedures,theagreementbetweentheimpedancevaluesand
neural telemetry thresholds, and the intraoperative test
performancetimeperformedwiththecurrentversionofthe
remoteassistantCR220andtheCustomSound®EPsoftware
(CSEP®).
Methods
This study was submitted to and approved by the
Research Ethics Committee under protocol CAAE:
43236915.5.1001.0068andapprovedunderOpinionnumber
1.076.661/2015.
Studycharacterizationandsite
This was a cross-sectional, multicenter study, involving
seven cochlear implant centers located in four
Brazil-ian states: São Paulo, Rio Grande do Norte, Paraná and
Pernambuco.Ofthese,sixcentersarelocatedinUniversity Hospitals,andallofthemarepartoftheBrazilianUnified
HealthSystem(SUS).
Participant’sselectioncriteria
No inclusion criteria were established for the age group,
consideringthatthemeasurestobeobtainedandthestudy
device should andcan be assessed at any age. Thus, the
studyincludedchildren,adultsandelderlyindividualswho
underwentcochlear implantsurgeryfromSeptember2014
toMarch2015,andwhoreceivedcochlearimplants
compat-iblewiththeremotecontrolusedinthisstudy.
Participants’characterization
Atotalof84subjects,ranginginagefrom2to83yearsand
time of auditory sensory deprivationof 5 to 672 months,
participatedinthisstudy.
The hearing loss etiologies and the implanted internal
componentsaredescribedinTable1.TheCI422devicewas usedin54%ofthesampleandtherest(46%)receivedtheCI 24RECA(Table1).
Datacollectionprocedures
Thefollowingequipmentwasusedtoperformtheproposed
procedures(impedancetelemetryandthresholdassessment
by automaticneural responsetelemetry--- AutoNRT):the
remote-controlunitcalledCR220®(Fig.1A)andtheCustom
Sound® EPSoftware,version4.2, coupledtoa connection
interface.
Bothproceduresrequireaconnectiontothespeech
pro-cessor (Nucleus 5) for communication with the internal
unit. The same processor was used in both test
situa-tions.Communicationwiththespeechprocessor,usingthe
wirelessCR220® andusingtheprogramminginterface,was
carriedoutthroughcable(Fig.1B).
The softwareCSEP® 4.2 wasusedfor traditional data
collection,i.e.,withouttheaidoftheremoteunit.Although it didnotrequiretheuse ofsoftwarefor datacollection,
the CR220® needed tobe coupled toa computer for the
quantitative analysis of the obtained data, in additionto datastorage.
Theimpedancetelemetrywascollectedinallactiveand
ground electrodes, and autoNRT wasrecorded for all 22
activeelectrodes,randomizingthecollectionorderbetween
the remote device (CR220®) and the standard equipment
(computer+interfacewithCSEP® 4.2software).
Themeasurement/runningtimewascollectedfromthe
moment the software wasturned on to start the
collec-tion.Theassemblyandtheconnectionoftheinterfaceand
thespeechprocessorwerenotcomputedforthestandard
procedure.
Dataanalysis
Followingthevaluesproposedbythecochlearimplant
man-ufacturer,theimpedancetelemetryresultswereclassified
as9(Fig.2):
Normal:values between0.565kOhms(k)and 30kOhms
(k)
Highimpedances(HI):values>30kOhms(k) Shortcircuit(SC):values<0.565kOhms(k)
AfterimportingthedatafromtheCR220® totheCustom
Sound®software,thevalueswerecollectedandastatistical comparisonoftheimpedancevaluesofelectrodesE22,E16,
E11,E6andE1,expressedinkOhms,wasperformedbetween
Table1 Demographicdataofthestudiedpopulationwithhearinglossetiologyandmodelofthecochlearimplantinternalunit inthestudypopulation.
Adults N(%) Children N(%) Total N(%) Etiology Idiopathic 8(9.5) 22(26.2) 30(35.7) Progressiveidiopathic 15(17.8) 2(2.4) 17(20.2) Meningitis 3(3.6) 3(3.6) 6(7.1) Genetic 0 4(4.8) 4(4.8) Cytomegalovirus 1(1.2) 3(3.6) 4(4.8) Syndromes 3(3.6) 1(1.2) 4(4.8) Congenital 0 3(3.6) 3(3.6) Rubella 2(2.4) 1(1.2) 3(3.6)
VIIInervehypoplasia 0 3(3.6) 3(3.6)
Otosclerosis 2(2.4) 0 2(2.4) Hypoxia 0 2(2.4) 2(2.4) Pretermbirth 0 2(2.4) 2(2.4) Traumatic 1(1.2) 0 1(1.2) Ototoxicity 0 1(1.2) 1(1.2) Toxoplasmosis 0 1(1.2) 1(1.2) Mumps 1(1.2) 0 1(1.2)
Internalunitmodel
CI24RECA 17(20.2) 22(26.2) 39(46.4)
CI422 19(22.6) 26(30.9) 45(53.6)
Total 36(42.8) 48(57.1) 84(100)
Figure1 (A)RemotecontrolunitcalledCR220®.(B)Setconstitutedbythesoftwareandprogramminginterfacewascarriedout bycable.
Thepresenceorabsenceofneuralresponsesinall elec-trodes was evaluated in both procedures and the neural responsethresholdvalues,expressedascurrentunits(cu), werecomparedbetweenthecollectionprocedureson elec-trodes E22, E16, E11, E6 and E1. Additionally, the tests’ measurement/performancetimethroughCR220® and Cus-tomSound® EPwererecordedandcompared.
Thepairedt-testwithp>0.05wasusedtocomparethe impedancelevels; Pearson’scorrelation test wasusedfor thecomparisonbetweenECAPthresholdsandthepaired
t-testwithp>0.01wasusedtocomparetherecordingtime oftheprocedures.
Results
Electrodeimpedance
Considering all 22 electrodes, the number of records obtained in the Impedance Telemetry test totaled 3690, of which 1845 were obtained through CR220® and 1845, throughCSEP®.Due tothepartialinsertion, three extra-cochlearelectrodeswereevaluated,whichdidnotgenerate validtelemetrymeasurements. Thus,outof3696 records, three measures of each condition (through CR220® and throughCSEP®)were excluded,totaling 3690records.Of
Table2 Description oftheelectrodestatus, representedby theimpedance valuesrecorded by CustomSound® (standard procedure)andbytheCR220® (remoteassistant).
CustomSound®n(%) CR220® n(%) Total n(%)
Normal 1837(99.40%) 1837(99.40%) 3674(99.40%)
Highimpedance(HI) 7
(0.19%) Coincident 3(0.16%) 3(0.16%) Discordant 1(0.05%) 0(0%) Lowimpedance(SC) 9 (0.24%) Coincident 4(0.22%) 4(0.22%) Discordant 0(0%) 1(0.05%)
Extracochlearelectrodes(partialinsertion) 3(0.16%) 3(0.16%) 6(0.16%)
Total 1848(100%) 1848(100%) 3696(100%) SC,shortcircuit. Electrode color codes Not tested Impedance OK Open circuit Short circuit
Figure2 Informationavailablefortheremoteassistantafter evaluating the impedance andinformation on the electrode status.
the3690records,99.4%(3674records)showedimpedance valueswithinthe normallimits. Regardingthe 16 records considered to be abnormal, 9 electrode SCrecords were obtained,astheyshowedimpedancevaluesbelowthe nor-malrange.
Asfortheotherabnormalrecords,7HIelectroderecords wereobtained,astheyshowedimpedancevaluesabovethe normalrange. Table2 shows the distributionof the
mod-ified impedance records per subject asa function of the
measurementobtainedthroughCR220® andthroughCSEP®.
Regardingtheabnormalimpedancerecords,therewasa
discrepancyinthedetectionofahighimpedancedetected
onlythrough CSEP®, anda low impedancedetected only
throughCR220®.
Regarding the impedance values measured in kOhms,
there was no statistically significant difference between
the values obtained through CR220® and through CS EP®
(Table3).
AutoNRT
The neural response thresholds obtained in 5 electrodes
wereanalyzed.Tenrecordscorrespondingtotwopatients
couldnotbeanalyzedduetolossofdataduringthetransfer
Table 3 Comparison of the impedance values (kOhms) recorded by Custom Sound® (standard procedure) and CR220® (remoteassistant). CustomSound® Mean(SD) CR220® Mean(SD) p E1 8.70(3.73) 8.34(3.69) 0.562 E6 8.64(3.88) 8.32(3.75) 0.590 E11 8.81(3.80) 8.56(3.54) 0.695 E16 9.36(3.88) 9.23(3.46) 0.864 E22 12.38(4.76) 11.67(4.05) 0.336 SD,standarddeviation. p>0.05(pairedt-test).
Table4 Comparisonof thepresence ofneural response recorded by Custom Sound® (standard procedure) and by CR220® (remoteassistant). CustomSound® N(%) CR220® N(%) Presence 361(88.69) 351(86.24) Absence 46(11.31) 56(13.76)
fromtheCR220® tothecomputerandthreeelectrodes of thesame patientwerenotmeasured becauseofa partial insertion,totaling814records,with407ofthemobtained duringeachprocedure.
In the measurements obtained through CR220®, there wereECAPresponsesin351records,whereasintheCSEP®, therewereECAPresponsesin361records(Tables4and5).
RegardingtheECAPthresholds,therewasamoderateto
strongcorrelationbetweenthethresholdsobtainedthrough
CR220® and CSEP® for the assessedelectrodes E22, E16,
E11,E6andE1(Fig.3).
Testperformancetime
The meandurationoftheprocedures(impedance
teleme-try and neural response telemetry) through CR220® was
260 240 220 200 180 160 140 120 100 120 140 160 180 200 220 240 260 EP CR Pearson’s correlation E6 E1 E11 E16 E22 0.91 0.90 0.83 0.82 0.79
Figure3 CorrelationbetweenECAPthresholdsmeasuredthroughCR220® andCustomSound®EPonallcollectedelectrodes.
Table5 Comparisonoftheneuralresponsethresholds(in current units---cu) recordedby Custom Sound® (standard procedure)andbyCR220® (remoteassistant).
CustomSound® Mean(SD) CR220® Mean(SD) p E1 196.01(21.88) 193.30(19.54) 0.028 E6 196.68(17.67) 194.99(16.88) 0.016 E11 192.79(14.01) 193.38(14.68) 0.235 E16 184.65(19.57) 184.34(18.18) 0.249 E22 182.19(20.74) 179.21(15.39) 0.191 SD,standarddeviation.
Table6 Meantime(inminutes)toperformtheprocedures throughCR220® andCSEP®forthetwoelectrodemodels(CI 422andCI24RECA).
CR220® CSEP®
Mean(SD)(inminutes)
CI422 5.20±1.39a 7.75±4.00
CI24RECA 5.68±3.00a 6.98±2.65
Total 5.42±2.28a 7.39±3.44
SD,standarddeviation.
a p<0.001---statisticallysignificant(pairedttest).
7.39min. This differencewasstatistically significant. The analysisobtainedbydevicemodelalsoshowedastatistically
significantdifferenceregardingtheprocedureperformance
time.ForbothNucleus422andNucleusFreedom(CI24RE
CA),proceduredurationwassignificantlyshorterwhenusing CR220® (Table6).
Discussion
Ofthe84participantsinthissample,somehadhearingloss
caused by etiologies that could lead to cochlear
ossifica-tionand,perhaps becauseofthis,threeelectrodesof the samepatientwerenotmeasuredbecausetherewasapartial insertion,whichreducedthenumberofrecordsobtainedin
AutoNRT.
Anotherfactorofresultexclusioninthissamplewasthe non-utilizationofrecordsoftwopatientsduetolossofdata
tobeanalyzedintheCR220® whentransferredtothe com-puter.AlthoughtheCR220® isadevicethatiseasytohandle andcarry,itshouldbeemphasizedthatitdoesnotalloweasy numericalvisualizationofdata,whichdictatestheneedto exportthedataforlateranalysisinacomputer.
Whenanalyzing theimpedancetelemetry,itwasnoted
thattherewasnostatisticallysignificantdifferencebetween
thevalues obtained through CR220® and throughCS EP®,
when considering the impedance values of the
elec-trodesmeasuredinkOhms.However,somesubjectsshowed
electrodes in high impedance (HI) or short circuit (SC)
and generally, in these situations, the altered electrodes
detected through CR220® were also detected through CS
EP®,corroboratingtheconceptofsimilaroperationofthe
twodevices regardingimpedancetelemetryperformance.
The reasonfor randomizationof the order of evaluations
intheintraoperativemomentwasbecauseimpedance
val-uestendtodecreaseaftertheconstantpassageofcurrent
through the electrode.10 The discrepancy found in high
impedance detection may be due to an air bubble that
dissipated at retest with the second procedure.5
How-ever,anelectrodewithalteredimpedancedoesnotaffect
the course or conduct at the intraoperative momentand
may be clinically circumvented at the speech processor
programming.
Regardingthe ECAPthresholds,ingeneral, amoderate
to strong correlation was found between the thresholds
obtained through CR220® and CS EP® for the evaluated
electrodes.The differencesfound for the RE CAwere: in
electrodes E1 and E6, they are not clinically
representa-tive,butthesedifferences canbecreditedtodifferences inthealgorithmsusedfortheAutoNRT(expertsystem)in CSEP® and in theCR220® (decision tree). Astudy of 130
subjects using the same devices (CR220® and CS EP®) to
obtainECAPshowedastrongcorrelation(r=0.90and0.97, respectively)betweentheresults.11 Thehighernumberof
absent responses with the remote control could suggest
that, in these situations, it would be necessary to
con-firm the neural response through the standard procedure
that allows the use of advanced stimulation parameters,
such asincrease in pulse width or the number of events
averaged.
Whenanalyzingtherecordingtime,themeandurationof
theprocedures(impedancetelemetryandneuralresponse
telemetry) using the CR220® was 5.42min and, for the
difference.The analysisobtained perdevicemodel,when
comparingthe testsin patientsimplantedwithNucleusCI
422andwithNucleusFreedom(CI24RECA),theduration
ofthe procedureswasshorterwhen usingCR220®,witha
statisticallysignificantdifferenceinthetimeofthe proce-dures.
Both technologies have been previously studied by
Tavartkiladzeetal.8tomeasureintraoperativeECAPdata.
The authorscollected the measures from81 childrenand
foundthat themeantimetomeasurethe ECAPthreshold
usingthe CustomSound® software was 6.2min (SD±1.0)
vs.4.8min(SD±0.7)fortheremotedevice(CR120®).The
ECAPthresholdsmeasuredwithCustomSound®softwareand
CR120® hada Pearsonproduct-momentcorrelation
coeffi-cientforallelectrodesof0.92(p<0.01);withanabsolute differencemeanof6currentunits(SD±6).Theyconcluded thatthereisasignificantreductioninthetimetomeasure ECAPthresholdswiththeuseoftheremotedevice(CR120®).
Moreover,thethresholdvaluesmeasuredwiththeCR120®
andtheconventionalsoftware(CustomSound®)were equiv-alent.
In a study carried out with 12 patients12 the authors
obtainedsuccessfulanduneventfulrecords,withtest dura-tionofapproximately4min.Inasampleof130patients13the
meantimeduringthe procedurescorresponded to7.4min
(SD=1.9) and 5.4min (SD=1.0) for CS EP® and CR220®,
respectively.ThesedatashowthatCR220® provideda22%
decrease in intraoperative time when compared to the
conventional method(p<0.001). In ourstudy, we didnot
evaluate the time of transference tothe surgical center,
orthewaitingtime,onlythemeasurementtime.However,
Tavartkiladzeetal.11 evaluatedfromthetimeoftransfer,
equipmentpreparation,waiting,measures,equipment
stor-ageandwaitingtime.Fortheauthors,ifweconsideraclinic with100surgeriesperyear,thetimetheaudiologistsaved byutilizingtheintraoperativetestcorrespondstothetime occupiedduring2monthsintheclinic,insteadofthegoing to,comingfromandtheunproductivewaitintheoperating room.
Humphriesetal.12 andOlusesietal.13 alsopointedout
thattheremotecontrolcanbeeasilyusedbysurgeonsand assistantswithouttheneedfortheaudiologisttobepresent
intheoperatingroom.
The evaluationof the impedancesand neuralresponse
thresholds are not the most important, but they are the
only possible teststo beperformed duringthe
intraoper-ativemoment.6,14---17Therefore,theresultsofthisstudydo
notsupportthereplacementoftheCustomSound®EPbythe CR220®,buttheydemonstrateaneffectiveandfast alterna-tivefortheperformanceofbasictestsduringtheCochlear Implantsurgery,insituationswhereitisnotpossibletohave anaudiologistintheoperatingroom.
Conclusion
The use of the CR220® provided successful records
for impedance telemetry and automatic neural response
telemetry.
Therewasnostatisticallysignificantdifferencebetween
theimpedancevaluesobtainedthroughCR220® andCSEP®
4.2.
RegardingtheAutoNRT,therewasamoderatedtostrong
correlationbetweentheECAPthresholdsobtainedthrough
CR220® and throughCS EP®. A higher number of records
showingthe absenceof ECAPwerefound forthe CR220®.
ThemeantimetoperformtheproceduresusingtheCR220®
wassignificantlylowerthanwithCustomSound® EP.
Conflicts
of
interest
The authorsdeclare noconflictsofinterest andthatthey
have not received any monetary bonuses, aid or fees
involvedwiththestudy.
Authors Valeria Oyanguren, Herbert Mauch and Marcia
Kimurahaveanemploymentrelationshipwiththecochlear
implantcompanyresponsibleforthetechnologyusedinthe
study.Author MariaValéria Schmidt Goffi-Gomez provides
technicalconsultingservicestothesamecompany.
Acknowledgement
The authors would liketo thankMs. FlaviaCintra for the
carefulstatisticalanalysisofthedata.
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