www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
ORIGINAL
ARTICLE
Cochlear
implant
revision
surgeries
in
children
夽
Maria
Stella
Arantes
do
Amaral
a,∗,
Ana
Cláudia
Mirândola
B.
Reis
b,
Eduardo
T.
Massuda
b,
Miguel
Angelo
Hyppolito
baUniversidadedeSãoPaulo(USP),PósGraduac¸ão,FaculdadedeMedicinadeRibeirãoPreto,HospitaldasClínicas,Divisãode
Otorrinolaringologia,RibeirãoPreto,SP,Brazil
bUniversidadedeSãoPaulo(USP),FaculdadedeMedicinadeRibeirãoPreto,DepartamentodeOftalmologia,
OtorrinolaringologiaeCirurgiadeCabec¸aePescoc¸o,RibeirãoPreto,SP,Brazil
Received6April2017;accepted29January2018 Availableonline16February2018
KEYWORDS Cochlearimplant; Sensorineuralhearing loss; Hearingloss Abstract
Introduction:Thesurgeryduringwhichthecochlearimplantinternaldeviceisimplantedisnot entirelyfreeofrisksandmayproduceproblemsthatwillrequirerevisionsurgeries.
Objective:Toverifytheindicationsforcochlearimplantationrevisionsurgeryforthecochlear implantinternaldevice,itseffectivenessanditscorrelationwithcertainvariablesrelatedto languageandhearing.
Methods:Aretrospectivestudyofpatientsunder18yearssubmittedtocochlearimplantsurgery from2004to2015inapublichospitalinBrazil.Datacollectedwere:ageatthetimeof implan-tation,gender,etiologyofthehearingloss,audiologicalandorallanguagecharacteristicsof eachpatientbeforeandaftercochlearimplantsurgeryandanyneedforsurgicalrevisionand thereasonforit.
Results:Twohundredandsixty-fivesurgerieswereperformedin236patients.Eightpatients received abilateral cochlear implantand 10 patients required revision surgery. Thirty-two surgeries were necessary for these10 children (1 bilateral cochlearimplant), of which 21 wererevisionsurgeries.In2children,cochlearimplantremovalwasnecessary,without reim-plantation,onewith cochlearmalformationduetoincompletepartitiontype Iandanother dueto trauma. With respectto thecause for revisionsurgery,ofthe 8children who were
夽 Pleasecitethisarticle as:AmaralMS,Reis AC,MassudaET,HyppolitoMA. Cochlearimplant revisionsurgeriesin children.Braz J
Otorhinolaryngol.2019;85:290---6.
∗Correspondingauthor.
E-mail:[email protected](M.S.Amaral).
PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.
https://doi.org/10.1016/j.bjorl.2018.01.003
1808-8694/©2018Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen
successfully reimplanted, fourhad cochlearcalcificationfollowing meningitis, onefollowed trauma,oneexhibitedafacialnervemalformation,oneexperiencedafailureofthecochlear implant internaldevice andone revisionsurgery was necessary becausethe electrodewas twisted.
Conclusion: Theincidenceofthecochlearimplantrevisionsurgerywas4.23%.Theperiod fol-lowingtherevisionsurgeriesrevealedanimprovementinthesubject’shearingandlanguage performance,indicatingthatthesesurgeriesarevalidinmostcases.
© 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; Perdaauditiva neurossensorial; Surdez
Cirurgiasrevisionaisdeimplantecoclearemcrianc¸as Resumo
Introduc¸ão: A cirurgiapara aimplantac¸ão dodispositivo internodo implantecoclearnãoé inteiramentelivrederiscosepodeapresentarproblemasqueexigemcirurgiasrevisionais.
Objetivo: Verificaraincidênciadasindicac¸õesdecirurgiasrevisionaisparaaimplantac¸ãodo dispositivointernodoimplantecoclear,suaefetividadeecorrelacionaràsvariáveisrelacionadas àscategoriasdelinguagemeaudic¸ão.
Método: Estudo retrospectivo de pacientes menores de 18 anos submetidos à cirurgia de implantecoclearde2004a2015emumhospitalpúbliconoBrasil.Osdadoscoletadosforam: idadenomomentodaimplantac¸ão,sexo,etiologiadasurdez,característicasaudiológicaseda linguagemoraldecadapacientenopréepós-operatório,necessidadederevisãocirúrgicae razãoparaela.
Resultados: Foramfeitas265cirurgiasem236pacientes.Oitopacientesforamsubmetidosao implantecoclearbilaterale10necessitaramdecirurgiaderevisão.Foramnecessárias32 cirur-giaspara essas10crianc¸as(umimplantecoclearbilateral),dasquais21 foramcirurgiasde revisão.Emduascrianc¸as,aremoc¸ãodoimplantecoclearfoinecessária,semrealizac¸ãode reimplante;sendoqueumadelasapresentavamalformac¸ãococlear,porpartic¸ãoincompleta tipoI;ea outra,devidoatrauma.Quantoàcausadanecessidadedacirurgiarevisional,dasoito crianc¸asquepermaneceramcomimplantecoclear,quatroapresentaramcalcificac¸ãococlear apósmeningite,seguidadetrauma(1),malformac¸ãodonervofacial(1),falhadodispositivo internodaIC(1)etorc¸ãodofeixedeeletrodos(1).
Conclusão:A incidênciade cirurgiasrevisionaisfoi de4,23%.Opós-operatório dascirurgias revisionaispermiteumamelhorianodesempenhodeaudic¸ãoenalinguagemdospacientes, indicandoqueessascirurgiassãoválidasnamaioriadoscasos.
© 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
Profoundsensorineuralhearinglossimpairstheindividual’s
ability to adequately communicate withthe environment
andcanhaveasignificantimpactonthelifestyleand per-sonalitydevelopmentofindividualswiththisdeficiency.1
Conventionalhearingaidsareeffectiveintreatingmost
hearingimpairments,butsomepatientscannotattainword
andsentencerecognition,evenwithapowerfulhearingaid. TheCochlearImplant(CI)isthecurrentalternativeforthese patients.2
TheCIisanauditorysensoryprosthesisthatallows indi-vidualswithsevereorprofoundsensorineuralhearinglossto
havethesensationof hearingandrecognizethesoundsof
speechthroughelectricalstimulationoftheauditorynerve fibers.Itconsistsofanexternalandaninternalunit,with
thelatterbeinginsertedsurgically. Theinternal CIdevice implantationsurgeryisnotcompletelyfreeofrisksandmay presentproblemsthatwillrequirerevisionsurgeries.3,4
The first report of a CI revision surgery occurred in
1985, by Hochmair-Desoyer and Burian.5 Sincethen,
sev-eralreports have addressed the safetyof this procedure,
including the preservation or increase of speech
percep-tionperformance, although there have also been reports
ofdecreasesinelectrodeactivation,decreasedspeech per-ceptionandintracochleartrauma,suggestingthatcochlear
reimplantationmayhavenegativefunctionalconsequences
in some patients, requiring careful consideration of the
expectedindicationsandbenefits.6---8
Indications for reimplantation follow the classification
proposed by Zeitler. It includes hardware and software
placement,surgical woundor skinflapcomplications,and
improvedcochlearimplanttechnology.Hardwarefailureis
definedasthecompleteinterruptionofauditoryinputwith
interrupted communication between internal and
exter-nal components. It is diagnosed by a failure in the CI
integrity test. Software failure is suspected in patients
withprogressiveorintermittentperformancefailureorwith non-auditorycomplaintssuchasearache,facialnerve stim-ulation,vertigo, or tinnitus.Device infection may appear asrednessandlossofintegrityoftheskinover the recep-torstimulatororanulceratedwound.Onceaninfectionor deviceexposureissuspected,antibioticsshouldbestarted immediately.Iftheinfectionpersists,deviceexplantationis
recommended,andreimplantationsurgerycanbeplanned
atthreetofourmonthsaftertheevent.Extrusionof
elec-trodes accompanied by decreased auditory performance
also requires reimplantation surgery. Factors related to
the CI internal unit extrusion may be classified as
intra-cochlear,suchasneo-ossificationthatmaypushthebundle ofelectrodesoutofthecochlea,orextracochlear,suchas
adhesionsandfibroticbands withinthe mastoidthatmay
pulltheelectrodebundle.
Especiallyin children, skullgrowth andother extrinsic factors,suchastraumaorinfection,cancausemigrationof theCIinternalunit.Currently,CIrevisionsurgeryisnot
indi-catedtoupdatethecochlearimplantationtechnology,but
itis expectedthatthenumberofreimplantationsurgeries willmarkedlyincreaseinthefutureforthisreason.9,10
Due to the need to advise surgeons on the expected
failurerateandauditoryperformanceafterreimplantation surgery,reports of revision surgeriesarerequired.
There-fore, it is highly recommended to have updated studies
that can clarify these problems and to analyze whether
theresultsvaryover time,withtheimprovementof
elec-trode technology and more modern surgical implantation
techniques.10
Additionally,suchreportscanhelptopatientseducation whoarecandidatesforCIsurgeryontherisksand possibili-tiesofsurgicalreinterventions.
Therefore,theaimofthisstudywastoidentifythe inci-denceofCIrevisionsurgeriesinapublicservicelocatedin thecountrysideofthestateofSãoPaulo,Brazil,accredited bytheMinistryofHealthtoperformthistypeofsurgery,its effectivenessandcorrelatethemtothevariablesrelatedto thedevelopmentofauditoryabilitiesandorallanguage.
Methods
Aretrospectivestudywascarriedoutbyreviewingthe medi-calrecordsofpatientsunder18yearsofagewithsevereand
profoundbilateral hearingloss whounderwentCIsurgery,
who had used the device for at least one year, and had
undergoneCIrevisionsurgerybetween2004and2015.
Data collection began after approval of the Research
Ethics Committee of the institution, under number CAAE
65067317.4.00005440.
Therefore,thefollowingdatawereobtained:ageatthe
timeofimplantation;gender;etiologyofthehearingloss; categoriesofauditory perception(Geers,1984)11 andoral language(Bevilacquaetal.,1996)12ofeachpatient,inthe
pre-andpost-CIphase;CIbrand;needforsurgical reinter-ventionandthereasonthatledtotherevisionsurgery.
The results for quantitative variables are shown as
mean and standard deviation (mean±SD) and
categori-cal variables as frequency/percentages. The comparisons
for independent samples were performed using the
Mann---Whitney test and, for the dependent samples, the
Wilcoxon rank-sum test. Correlations were assessed using
Spearman’stestandthecategoricalvariablesusingthe
Chi-Squaretest. Allanalysisprocedureswere performedusing
JMP® 10.0software(SASInstituteInc,Cary,NC,USA). Sig-nificancewassetatp<0.05.
Results
During thestudy period from2004 to2015, 265 surgeries
wereperformedin236patientswhowereyoungerthan18
yearsofage.Ofthese265operations,eightweresequential bilateralCIimplantation(3.39%).
Ofthe236patientssubmittedtoCIsurgery,10patients requiredrevisionsurgery(4.23%).Thirty-twosurgerieswere necessary inthese10children: thefirst10surgerieswere performedfordeviceimplantation,onebilateralsequential implantationand21(7.92%)revisionsurgeries(Table1).
Ofthe10children submittedtorevisionsurgeries,five
werefemalesandfivemales,withameanageof5.1yearsat thefirstCIsurgery.Themeanageatthetimeoftherevision surgerywas6.5years.
Initially, in these 10 children, five surgeries were
per-formed on the left side, four on the right side, and the
sequential bilateral implantation was performed in one
child.
At the time of the revision surgery, only one child
required change of the reimplantation side (Subject 2)
(Table2),andthischangewasperformedafterthreerevision surgeriesontherightsideand,therefore,thefourthsurgery wasperformedontheleftside,duetotraumaattheCIsite, followedbyexposureoftheelectrodes(Table3).
Regardingthe hearing loss etiology, of the 10 children
who required revision surgery, four lost hearing due to
meningitis,threearestillunderinvestigation(idiopathic),
Table1 Samplecharacterization by numberofsurgeries performedfrom2004to2015andbyindividual.
N % Perpatient Numberofpatients submittedtoCIsurgery 236 100 Numberofpatients submittedtoBilateralCI surgery 8 3.39 Numberofpatients submittedtoàCIrevision surgery 10 4.23 Persurgeries
TotalnumberofCIsurgeries 265 100 NumberofCIrevision
surgeries
21 7.92
Table2 Datarelatedtoage,genderandimplantedearoftheindividualssubmittedtorevisionsurgery.
Subject Gender AgeatCIsurgery(years) Ageatrevisionsurgery Implantedside Re-implantedside
1 F 5.4 5.6 L L 2 F 3.2 7.4 R L 3 F 3.8 7.0 R R 4 M 4.7 8.0 L L 5 F 8.6 9.5 R R 6 M 3.5 4.2 L L 7 M 1.2 1.2 L L 8 F 6.5 6.5 R R 9 M 1.8 3.3 RandL RandL 10 M 12.3 12.3 L L
CI,cochlearimplant;F,female;M,male;L,left;R,right.
Table3 Datafrompatientssubmittedtorevisionsurgery. Subject Numberof CIsurgeries Numberof revision surgeries Currently hasCI Etiologyofhearing loss
Causeofrevisionsurgery
1 2 1 Yes Idiopathic Twistingoftheelectrode
2 5 4 Yes Idiopathic Trauma
3 5 4 No Genetic---cochlear malformation
Genetic---cochlearmalformation
4 2 1 Yes Idiopathic Genetic---facialnervemalformation 5 2 1 Yes Autoimmune CIfailure
6 5 4 No Ototoxicity Trauma
7 3 2 Yes Meningitis Post-meningitiscalcification---extrusionof theelectrodes
8 2 1 Yes Meningitis Post-meningitiscalcification---false trajectory
9 4 2 Yes Meningitis Post-meningitiscalcification---CIextrusion 10 2 1 Yes Meningitis Post-meningitiscalcification---false
trajectory
CI,CochlearImplant.
onehadanautoimmunepathology,onehadhearinglossdue toototoxicity,andinonehearinglosswasduetocochlear malformation(incompletecochlearpartitionTypeI).Itwas necessary toremovethecochlear implantinternal unitin two children, without reimplantation (Subjects 3 and 6). For Subject 3, who had cochlear malformation, the rea-son forthe removalwasrepetitivemeningitis, which first manifested more than 2years after theinitial CI implan-tation. For Subject 6, the reason was external trauma to the CI region, followed by unresolved skin infection and extrusion of the device despite four revisionsurgical interventions.
Regarding the reason for the revision surgery, of the eightchildrenwhoweresuccessfullyreimplanted,fourhad cochlear calcification after meningitis (two children had extrusionoftheelectrodesandtheCIwasplacedinafalse trajectoryintwoofthem),followedbytraumainonechild. Inanotherchild,thefacialnervepositionnearthecochlea caused facial contraction. The CI internal device failure occurred in one child and in another it was necessary to perform the surgical revision, due tothe twisting of the electrodebundle(Table3).
Seven subjects initially received a Cochlear® CI, one
childreceivedan adaptedbilateral CI,andthreechildren receivedtheMed-el®brandofCI.Itwasnecessarytochange
theCI,maintainingthesamebrand,infourchildren (Sub-jects1,2,7and9).Intwoofthem,theCIbrand(Subjects 4and5)waschanged,sothatultimatelyallimplantswere
replacedby a Cochlear® device.It waselected tochange
fromthefull-bandelectrodetothehalf-bandperimodiolar deviceduetothedesiretopositiontheelectrodescloseto themodiolus,inordertoallowintracochlearstimulationby theelectricfieldthatwasmorelocalizedthanthefull-band electrodes(Table4).
Dataregardingthepatients’hearingandlanguage
cate-gorieswerecollectedinthepre-andpost-CIsurgeryphases withaninterval ofat least oneyear after theCIrevision surgery.Ofthe10childrensubmittedtotherevisionsurgery, eighthadprelingualdeafnessandtwohadpost-lingual deaf-ness(Subjects5and10)(Tables5and6).
Oftheeightchildrenwhoweresuccessfullyreimplanted,
onlyonechild didnotshowimprovementin auditory
per-ception (Subject 4). When we compared results related
Table4 CharacterizationofdevicesinthephasesofCIandrevisionsurgeries,perpatient(n=10).
Subject Brandof1stCI ChangedtheCI Brandof2ndCI Comment
1 Cochlear® Yes Cochlear®
2 Cochlear® Yes Cochlear®
3 Cochlear® No CIremoved
4 Med-el® Yes Cochlear®
5 Med-el® Yes Cochlear®
6 Cochlear® No CIremoved
7 Cochlear® Yes Cochlear®
8 Cochlear® No
9 BilateralCochlear® Yes--- Yes BilateralCochlear®
10 Med-el® No
CI,cochlearimplant.
Table5 Distributionoftheresults,relatedtothehearingcategory,11inthepre-CIandpost-revisionsurgeryphasesandgender,
perpatient(n=10).
Subject Gender Pre-CI Post-CI Improvement Comment
1 F 0 1 Y 2 F 1 6 Y 3 F 1 0 N CIremoved 4 M 1 1 N 5 F 2 6 Y 6 M 0 0 N CIremoved 7 M 1 3 Y 8 F 1 3 Y 9 M 0 3 Y 10 M 2 6 Y Mann---Whitneyp=0.83 Wilcoxon p=0.0234
CI,cochlearimplant;F,female;M,male;Y,yes;N,no.
Table6 Distributionofresultsrelatedtolanguagecategory,12inthepre-CIandpost-revisionsurgeryphasesandgender,per
patient(n=10).
Subject Gender Pre-CI Post-CI Improvement Comment
1 F 1 1 N 2 F 1 5 Y 3 F 1 1 N CIremoved 4 M 1 1 N 5 F 4 5 Y 6 M 1 1 N CIremoved 7 M 1 2 Y 8 F 1 2 Y 9 M 1 3 Y 10 M 2 5 Y Mann---Whitneyp=0.91 Wilcoxon p=0.0313
CI,cochlearimplant;F,female;M,male;Y,yes;N,no.
surgeryphases,asignificantdifferencewasobservedafter therevisionsurgery(WilcoxonSignedRanktest,p=0.0234) (Table5).
There was no correlation between the results of the
Hearing Category, obtained in the two studied phases,
whenconsidering theage variable(Spearman’srho=0.13;
p=0.723); nor there was any association with gender
(Mann---Whitney test, p=0.83). A weak correlation was
observedwhenanalyzingtheHearingCategoryperformance
inthepre-CIandpost-revisionsurgeryphaseswiththe sub-ject’sageatthetimeoftheCIrevisionsurgery(Spearman’s rho=0.31,p=0.38).
Theresults ofthe subjects’Language performanceare
reimplanted,twodidnotshowimprovementintheLanguage Categories12(Subjects1and4)(Table6).
When comparing the results related to the Language
Category12inthepre-CIandpost-revisionsurgeryphases,a statisticallysignificantimprovement(WilcoxonSignedRank Test,p=0.0313)wasobservedinsixofthesubjects,witha changeinatleastonecategory(Table6).
There wasno correlation between the Language
Cate-goryresultsinthetwoassessedphasesbytheagevariable (Spearman’srho=0.044,p=0.903)andtherewasno associa-tionwiththegendervariable(Mann---Whitneytest;p=0.91).
Therewasnocorrelation between theLanguage Category
performanceinthepre-CIandpost-revisionsurgeryphases andthesubject’sageatthetimeoftheCIrevisionsurgery (Spearman’srho=0.203;p=0.574).
Discussion
The indication for CIinternal device implantation surgery shouldconsiderthepossible needfor arevision operation ifclinicaltreatmentisnoteffective.Inthisstudy,thedata showedthat4.3%,ofthepatientsrequiredrevisionsurgery which is comparableto data from the literature (Lasig ---3.2%,Cote---5.4%, Battmer---3.8%).13---15 Ina comparative
study between adults and children, Brown et al.(2009)16
found a mean rate of 5.5%; 7.5% in children and 3.8% in
adults. Cullen et al. (2008)17 found a higher percentage
(11.2%)whenstudyingtwolargeCIservices,with approxi-mately1000childrenreceivingCIsduringthe14-yearperiod.
We observed that the etiology that most frequently
required revision surgery wasmeningitis, withfour of 10
children(40%)requiringthisprocedure.Therefore,patients withthisetiologywhoarecandidatesforCIsurgery,should
definitelyreceive informationabout thepossibleneed for
revision, as it is known that the chance of the need for
surgical revision is higher withthis pathology, due to the possibilityofcochlear calcificationaftermeningitis,which wasnotedinfourchildreninthisstudy.Thisincidence dif-fersfromthatfoundbyManrique-Huarteetal.(2016)10(1of 26patientsyoungerthan18years),maybeduetothehigher incidenceofmeningitisinourregion.
Coteetal.(2007)14reportedtheneedforsurgical
rein-tervention in 13.3% of the procedures performed in their
service,mostfrequentlysecondarytotrauma,ina popula-tionof adultsand children;a traumaticetiologyoccurred onlyinchildren.Thesedatacorroboratethefindingsofour study,sincein2(20%)ofthe10childrensubmittedto sur-gicalrevision,traumawasthecauseofthereintervention
andonechildhadtheinternaldeviceremovedandnot
re-implanted.
Studies indicate that revision surgery in the pediatric
population is more common, both because of surgical
complicationsandthegreaterlikelihoodoftraumainvolving theimplantedunit.17
Thus,we emphasisthattheinvolved professionalteam
theimportancetoadvisepatientsandfamiliesabout avoid-ingtraumatotheimplantbothbeforeCIsurgeryandlater duringtheirfollow-up.
A geneticetiologywasfound intwoof the10children
(20%)whorequiredrevisionsurgery,corroboratingthedata
reportedbyManrique-Huarteetal.(2016),10whofoundthis etiologyin19.2%ofpatientsyoungerthan18years.
Comparedwiththeinternaldevicefailureratespublished intheliterature,thepresentstudyshows afailureratein only10%ofcases(onechild),whichwasremediedby replac-ingtheCI,whichisdifferentthanthepercentageshownby Manrique-Huarteetal.(2016),10whichwas65.39%,thatis, 17of26childrenandadultpatientssubmittedtosurgeryat theirCenter.Thatstudyalsoreportedaninadequate elec-trodeinitialplacement,in5of26patients(19.2%),whereas itwas10%inthepresentstudysample.
Weobservedsignificantimprovementinhearingand
lan-guage whenwe comparedthe pre- and post-CI testing in
both the results of the hearing (p=0.0234) and language
(p=0.0313) categories, similartothat presented byRivas etal.(2008),6whoobservedhearingperformance improve-mentinthepostoperativeperiodin73% oftheirpatients. Cullenetal.(2008)17consideredthatthechildren’s
perfor-mance after the revision surgery was probably the same
or better than that before the procedure. However, this
improvement may requireseveral monthsor even a year
aftertherevisionsurgery,whichshouldalsobepartofthe informationprovidedtothefamily.
Another important factor to be considered is for CI
providers is to analyze and record the revision surgeries
regardless of the age group. The results of this analysis
shouldsupportactionstoimprovethequalityofguidelines, indicationsandinterventionsinpatientswhoarecandidates forCIsurgeryorCIusersand,thus,reducetheincidenceof reimplantationintheseservices.
Thisstudysuggeststhat,inadequatelyselectedpatients,
thebenefitofrevisionsurgerymayoutweigh theinherent
surgical risks. In the pediatric population, the
par-ents/guardiansshouldbeadvisedabout revisionsurgeries, theirmostfrequentcauses,risksandtheperformanceofthe childrenaftertheprocedure.
Conclusion
The incidence of revision surgeries was4.23%. The
post-operativeperiodoftherevisionsurgeriesdemonstratedan
improvementinthesubjects’hearingandlanguage
perfor-mance,showingthatthesurgicalindicationisvalidinthese cases.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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