Perfurações traumáticas da membrana timpânica: recuperação clínica imediata com o uso de fragmento de celulose bacteriana

www.bjorl.org

Brazilian

Journal

of

OTORHINOLARYNGOLOGY

ORIGINAL

ARTICLE

Traumatic

perforations

of

the

tympanic

membrane:

immediate

clinical

recovery

with

the

use

of

bacterial

cellulose

film

夽

Ana

Mariana

de

Moraes

Rebello

Pinho

_,

_Carolina

_Christofani

_Sian

_Kencis

_,

Dino

Rafael

Pérez

Miranda

_,

_Osmar

_Mesquita

_de

_Sousa

_Neto

a_{SantaCasadeMisericordiadeSãoPaulo,SãoPaulo,SP,Brazil}

b_{SantaCasadeMisericordiadeSãoPaulo,FaculdadedeCienciasMédicas,SãoPaulo,SP,Brazil}

Received12September2018;accepted11May2019 Availableonline11June2019

KEYWORDS Perforationofthe tympanicmembrane; Bacterialcellulose; Audiometry Abstract

Introduction:Perforation of the tympanic membraneis a reasonably frequent diagnosis in otorhinolaryngologists’offices.Theexpectantmanagementistowaitforspontaneoushealing, whichusuallyoccursinalmostallcasesinafewweeks.However,whilewaitingforhealingto becompleted,thepatientsmayexperienceuncomfortablesymptoms.Althoughsomeresearch suggeststheuseofvariousmaterialstoaidintherecoveryofthetympanicmembrane,none presentedrobustevidenceofimprovementinthecicatricialprocess.Nevertheless,the occlu-sionoftheperforationwithsomematerialofspecifictextureandresistancecanalleviatethe patients’symptomsandacceleratethehealingprocess.

Objective: Toevaluatetheclinical(symptomaticandfunctional)improvementafterthe place-mentofbacterialcellulosefilm(Bionext®)ontympanicmembraneperforations(traumatic). Methods:Weevaluated24patients,victimsoftraumaticperforationsofthetympanic mem-brane,whowereevaluatedintheOtorhinolaryngologyEmergencyRoom.Followingotoscopy andaudiometricexaminationwasperformed,beforeandaftertheuseofcellulosefilm occlud-ingthetympanicmembraneperforation.

Results:Twenty-four patients wereincluded, whosedegreeofoverall discomfortcausedby thetympanicmembraneperforationandthepresenceofsymptomsofautophonia,earfullness andtinnituswereinvestigated.Themeanscoreattributedtotheoverallannoyancecausedby tympanicmembraneperforation was7.79,decreasingtoameanvalueof2.25afterthefilm

夽 _{Pleasecitethisarticleas:PinhoAM,KencisCC,MirandaDR,NetoOM.Traumaticperforationsofthetympanicmembrane:immediate}

clinicalrecoverywiththeuseofbacterialcellulosefilm.BrazJOtorhinolaryngol.2020;86:727---33.

∗_{Correspondingauthor.}

E-mail:anampinho@hotmail.com(A.M.Pinho).

PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial. https://doi.org/10.1016/j.bjorl.2019.05.001

1808-8694/©2019Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen accessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).

application.Symptom evaluationalsoshowed improvementafter usingthefilm:autophonia decreasedfromameanvalueof6.25to2.08,tinnitusfrom7to1.92andearfullnessfrom7.29 to1.96.Theauditoryanalysisshowedmeanthresholdvaluesstillwithinthenormalrangeat lowandmediumfrequencies,withslighthearinglossatacutefrequencies,butwithsignificant improvementatallfrequencies,withtheexceptionof8000Hz,afterfilmuse.

Conclusion:Theuseofbacterialcellulosefilmfragmentontraumaticperforationsofthe tym-panicmembranepromotedimmediatefunctionalandsymptomaticrecovery intheassessed patients.

© 2019 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 Perfurac¸ãoda membranatimpânica; Celulosebacteriana; Audiometria

Perfurac¸õestraumáticasdamembranatimpânica:recuperac¸ãoclínicaimediatacomo usodefragmentodecelulosebacteriana

Resumo

Introduc¸ão: Aperfurac¸ãodamembranatimpânicaéumacondic¸ãoclínicarelativamente fre-quente em consultórios de otorrinolaringologistas. A conduta é quase sempre expectante, aguardandocicatrizac¸ãoespontânea,quecostumaocorrernaquasetotalidadedoscasosem algumas semanas. No entanto, enquanto não se completa, os pacientes mantêm sintomas desconfortáveis.Emboraalgumaspesquisassugiramousodemateriaisdiversosparaauxiliar na recuperac¸ão da membrana timpânica, nenhuma apresentou evidência substancial de melhorianoprocesso cicatricial.Por outrolado,aoclusãodaperfurac¸ãocomalguns mate-riaisdetexturaeresistênciaespecíficas poderiaaliviarossintomasdospacientesduranteo processocicatricial.

Objetivo:Avaliaramelhoriaclínica(sintomáticaefuncional)apósacolocac¸ãodepelículade celulosebacteriana(Bionext®)sobreaperfurac¸ãodamembranatimpânica(traumática). Método: Foramavaliadospacientescomperfurac¸õestraumáticasdamembranatimpânicaque deramentradanopronto-socorrodeotorrinolaringologia.Elesforamavaliadosemrelac¸ãoa suasqueixaseexameaudiométrico,anteseapósaaplicac¸ãodepelículadecelulosequeoclui aperfurac¸ãodamembranatimpânica.

Resultados: Foramincluídos 24pacientes, nosquais forampesquisadosograudeincômodo globalcausadopelaperfurac¸ãodamembranatimpânicaeapresenc¸adesintomasdeautofonia, plenitude auriculare tinnitus.A médiada nota atribuídaao incômodoglobal causado pela perfurac¸ãofoide7,79;caiuparavalormédiode2,25apósaaplicac¸ãodapelícula.Aavaliac¸ão dossintomastambémapresentoumelhoriaapósusodapelícula,autofoniacaiudevalormédio de6,25para2,08;zumbidode7para1,92eplenitudeauricularde7,29para1,96.Aanálise auditivaapresentouumvalormédiodelimiaresaindadentrodanormalidadeemfrequências baixase médias,com perdade audic¸ão leve em frequências agudas,porém com melhoria significanteemtodasasfrequências,comexcec¸ãode8000Hz,apósacolocac¸ãodapelícula. Conclusão:A aplicac¸ão de fragmento depelícula de celulosebacteriana sobre perfurac¸ões traumáticasdamembranatimpânicapromoveurecuperac¸ãofuncionalesintomáticaimediata nospacientesestudados.

© 2019 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

Perforationofthe tympanicmembrane(TM) isa frequent occurrencetoday, most often caused by trauma. In cases oftraumaticperforation,themaincauseisassociatedwith violencesufferedbythepatientcausedbyanotherperson orbyoneself,duringthemanipulationof sharpobjectsin theexternalauditorymeatus.

Asaconsequenceofthisperforation,theremaybe hear-ing loss, usually of the conductivetype, accompanied by symptomssuchasearfullness,tinnitus,autophonyand mid-dleearinfections.1_{Thehearinglossperceivedbythepatient}

becomesmoreintensethegreatertheperforationis,being worseatlowerfrequencies.2

TraumaticperforationoftheTMcanhealspontaneously in 70---90% of cases, but the duration of the process

until the complete closure may be long and sometimes take onemonth or longer.3 _{Surgical management,suchas}

tympanoplastyormyringoplastytoclosethetympanic perfo-rationismoreinvasiveandcostlyand,therefore,isanoption reservedforcasesinwhichtherewasnospontaneous reso-lutionofthecondition.Thus,forthesereasons,theprimary treatmentisaconservativeone.4,5

The process of tympanic membrane healing occurs throughthemigratoryproliferationofthekeratinized squa-mousepithelium,itsoutermostlayer,whichadvancesinto the connective tissue,and the permanence of the perfo-ration occurswhen this growth continuesinto the border ofitsmargin, towardthemiddleear.6_Inorderto

acceler-atetheclosureofthisperforation,severaltechniqueshave beenemployed,andnumerousstudieshaveusedbiological materialsassupportorgrafts.

The earliestattempts toclosethetympanicmembrane with heterologousmaterials appeared in the seventeenth century. Banzer in 1640 used a pig bladder fragment for thispurpose.Inaddition,Toynbeeappliedarubber-like sub-stance in 1853, while Blakeused a paperdisk in 1887.7,8

Sincethen,severalothermaterialshavebeenemployedin thesearchforanidealmaterial.

The paper graft, introduced byBlake, is stillthemost widelyusedmaterial.CamnitzandBostin19859_appliedthe

paperpatchundertopicalanesthesiain50patients, demon-stratingtheefficacyofthismethod,withrecoveryratesof 92%andhealingin2---3weeks.Theuseofbiological mate-rialshasalsobeenemployed.Sayinetal.10 _usedagraftof

hyaluronicacidester(Epifilm®)andcompareditwith spon-taneoushealing.Atotalof155patientswerefollowedfor months and, although there wasno significant difference between the efficiencyof the twomethods, the use of a hyaluronicacidpatchshowedafastertympanicmembrane closureprocess.

Thevastmajorityofstudieshavenotshownasignificant differencebetweenthesenewtechniquesandtheprocess ofspontaneoushealinginrelationtofasterormorefrequent recovery.However,oneimportantobservationisthatsuch attemptsdidnotshowanyharmtothehealingprocessor tympanicmembrane.11

Consideringtheexpectantbehaviorinthemanagement oftraumatic perforationofthe TMandthepersistenceof patients’ uncomfortable symptomsuntil complete healing oftheTM,thisstudyproposestheplacementofabacterial cellulosefilm(Bionext®)fragmentonthetympanicdamaged area,aimingatofferingimmediatefunctionalrecoveryand thuspromotesymptomandfunctionalrelief.Whereasmost literature studies describe the placement of autologous or heterologousmaterial withthe objectiveof evaluating thehealingvelocityofthetympanicmembrane,thisstudy has the advantage of proposing the evaluation of clinical improvement(symptomaticandfunctional)afterthe place-mentofBionext® filmfragment.

Cellulose

film

---

Bionext

Bionext®filmoriginatesfromthefermentationofthe Aceto-bacterxylinumbacteria.Thecellulosesynthesizedbythese bacteriamaypresentasaflexible,semitransparentfilmor a gelatinous sheet, approximately 0.5-cm thick. After its

processing, it contains noadditives, being pure cellulose consistingofbiodegradable,non-toxic,non-pyrogenic,and sterilepolysaccharides.Itisaninertsubstance,very resis-tantandinsolubleinalltheorganicsolvents;ithasspecific physicalcharacteristics,suchas:definedpermeabilityto flu-idsandgases,tensileandelongationstrength.Itiscurrently usedasatemporaryskingraftandisusefulforthedressing ofburn injuries, dermabrasion or skin donorareas.12---14 _It

hasalsobeenusedasasubstituteformeninges,asa coat-ingmaterialforintravascularstentsandvaricoseulcersof limbs.15

Katoetal.16_{evaluatedtheresponseoftheTMepithelium}

andtympaniccavitymucosaofguineapigsexperimentally submittedtotraumaticperforationafterreceivingimplants ofthecellulosefilmproducedbytheAcetobacterxylinum

bacteria,showingthatthehealingprocesswhenusingthis materialoccursinasimilarwaytothespontaneoushealing, without any tissue damage, including functional recovery assessedbyotoacousticemissions.Theyconcludedthatthe histologicalparametersofacuteinflammation(neutrophils, fibrin and vascular neoformation) and chronic inflamma-tion (fibroblasts, mononuclear cells --- lymphocytes and macrophages),ingeneral,behavesimilarlyinthepresence ornotofthecellulosefilm.Thisbehaviorisalsoobservedin thelong-termevaluation.

ConsideringtheconclusionofthestudybyKatoetal.16

andseveralotherstudiesthathavealreadyusedthis mate-rialinguineapigsorhumans,itcanbeobservedthatitposes minimalrisk,asitisabiologicalandinertmaterial.Asan observation,theremaybeaninflammatoryallergicreaction ifthepatientisallergictothecellulosecompoundofwhich Bionext® ismade.

Material

and

methods

The study is a prospective clinical trial, which included patientswithtraumaticperforationsofthetympanic mem-brane, over 18 years of age, whowere evaluated in the Otorhinolaryngology Emergency Department between May 2015andSeptember2016.The studywasapprovedinthe Ethics Committee of the institution Santa Casa de Mis-ericórdia de São Paulo under opinion number 912.218 ---12/14/2014.

Patientswhohadeitherotorrheaorwereunabletogive arelevanthistoryatthefirstconsultationortocollaborate withthephysical examination and/or thebacterial cellu-losefilmplacementprocedureonthetraumatizedTMwere excludedfromthestudy.

Once the inclusion criteria had been met, patients answeredaquestionnaire inwhichtheygraded the inten-sityofoverallannoyancecaused bythecondition,usinga scalefrom0(zero)to10(ten),withzerobeingno annoy-anceand10themaximumdegreeofannoyance.Theyalso reported whether they noted tinnitus, autophonia or ear fullness, and classified these symptoms by the degree of annoyance,using the same scale from 0 to10. Then the patientunderwentatonalandvocalaudiometrytestto iden-tifyauditorythresholds, whichcouldcharacterize hearing impairment.

The bacterial cellulose film fragment was then placed over the tympanic perforation, in a lateral position to

the TM, under direct visualization with the aid of a sur-gical microscope. The DF Vasconcelos microscope, model M900,wasused,andthemagnificationvariedaccordingto theneed and thecomfortof the examiner.The design of thiscellulose fragment was carriedout with acalculated size to be slightly larger than the area of the perfora-tion so as to completely cover it and remain supported by the remaining TM. For greater adhesion to the outer layeroftheTM,asmallamount(approximately1---2drops) of saline solution, was placed directly on the bacterial cellulose film. The procedure was performed without the need for local anesthesia and was well tolerated by all patients.

Oncethe Bionext® filmfragmentwasplaced,thesame questionnairequestionswererepeated,andanewtonaland vocal audiometrytest wasperformed. Thus, we obtained elementstoobjectivelyandsubjectivelyevaluatewhether theclinical (symptomatic andfunctional) recovery of the patientoccurred,withthepatientsbeingtheirowncontrols.

Fig. 1 depicts the video-otoscopy image of two patients beforeandaftertheplacementoftheBionext® film.

All patients whounderwent Bionext® placementhad a return consultation scheduled for 30 days after the first consultationfor thereassessmentofotoscopy andclinical status,reportingwhethertheauditorysymptomspersisted inrelationtothelastconsultation.Duringthisperiodthey wereadvisedtoprotecttheaffectedearfromcontactwith water,beingalsoprohibitedfromimmersioninaswimming pool or the sea. The patients were advised to return at anymomentiftherewasanycomplaintassociatedwiththe affectedear.

The Wilcoxon test was used for non-parametric varia-bles and Pearson’s correlation coefficient for comparison betweenquantitativevariables.

Results

Overall, 24 patients met the inclusion criteria and were selected for the study. Among them, 45.8% (n=11) were malesand54.2%(n=13)females.The agerangedfrom19 to58years,withameanof34±10.4years.Table1 summa-rizesthemainepidemiologicaldataofpatientsthatmetthe inclusioncriteria.Italsoshowsdataonthetimebetweenthe traumaandthefirstconsultation,thesideaffectedbythe perforation and theareaof the tympanicmembrane that wasaffectedbytheperforation.

Regardingtheetiology,themostcommonwasviolence, in 62.5% (n=15) of the cases, which included victims of

Table1 Epidemiologicaldata. Gender Male 11(45.8%) Female 13(54.2%) Affectedside Right 6(25%) Left 18(75%)

Age 34±10.4yearsold

Elapsedtime 8.6±4.9days

PerforationArea 25%±14%

Table2 Questionnairedata---meanscoresassignedtoeachcomplaint.

Overallannoyance Autophony Tinnitus Earfullness

Initialevaluation 7.79±2.6 6.25±3.1 7±3.37 7.29±1.96 Afterfilmplacement 2.25±2.1 2.08±2.2 1.92±1.97 1.96±2.03 p-Value <0.001 <0.001 <0.001 <0.001 Wilcoxontest. 9 8 7 6 5 4 3

Mean of assigned score

2 1 Annoyance Autophony Tinnitus Ear fullness

Initial evaluation After film placement 0

Figure2 Comparisonbetweenthemeanoftheinitialvalues andafterthefilmplacement.

aggression such as punches and slaps, and perforations causedbysportsinjuries.The secondmostcommoncause wastheintroductionofapointedobjectintotheexternal auditorymeatus,in 33.3%(n=8)of thecases,and finally, onlyonepatient(4.5%)hadaperforationduetoanabrupt Valsalvamaneuver,whileattemptingtopreventasneeze.

The questionnaire data, related to the scoring of the symptomsinascalefrom0to10,aresummarizedinTable2. Itshowsthemeanvaluesforeachcomplaintatthetimeof the first evaluation and after the cellulose film fragment placement.Allpatientsreportedearfullnessandtinnitus, while autophony waspresent in 91% (n=22).All reported adecreaseintheannoyanceafterthefilmplacement,with significantdifferenceforallanalyzedvariables.Fig.2shows thecomparisonbetweenthevaluesatthefirstandthe sec-ondmomentsforeachsymptom.

Table3showsthemeanvaluesfoundforeachfrequency inthetonalaudiometry,beforeandafterthecellulosefilm placement,whileFig.3showsthisexamatbothmoments. The difference between the values showed a significant

-10 250 500 750 1k 1,5k 2k 3k 4k 6k 8k 0 10 20 30 40 50 60 70 80 90 100

Figure3 Tonalaudiometryimage,comparingthemeans of theinitialvaluesinred,andafterthefilmplacement,inblue.

improvement(p<0.005)forallfrequencies,exceptforthe 8000Hzfrequency(p=0.124).

The vocal audiometryincluded onlythe Speech Recog-nition Threshold (SRT) analysis. The initial SRT was 21.25dBHL±8.50,whereas itwas13.13dBHL±7.49after the film placement. This difference was also significant (p<0.005).

We investigated whether there was any association between the perforation area and the score attributed to each complaint, and no correlation was found. Simi-larly, thesize of the perforation area and the magnitude of the improvement demonstrated by the patient (the difference between the first and second moments) were compared, and no significant relationship was identified. ThiscomparisonwasperformedusingPearson’scorrelation coefficient.

Only50%(n=12)ofthepatientscamebackforthe sched-uled return consultation after one month, and of these,

Table3 Meanvaluesforeachtonethresholdobtainedatthetimeofthefirstevaluationandafterfilmplacement.

Initialmoment Afterfilmplacement p-Value

250Hz 23.13dBHL±12.92 15.21dBHL±8.6 <0.001 500Hz 18.54dBHL_±10.05 12.08dBHL_±7.21 <0.001 1000Hz 19.38dBHL±9.36 12.08dBHL±8.57 0.001 2000Hz 23.33dBHL_±16.8 9.65dBHL_±18.59 0.001 4000Hz 24.79dBHL±20 18.54dBHL±21.23 <0.001 8000Hz 27.50dBHL±19.9 25dBHL±20.43 0.124 Wilcoxontest.

16.6% (n=2) did not have a fully healed tympanic mem-brane yet. These two patients showed, at the moment ofthefollow-upconsultation,thepresence ofgranulation tissuenexttocellulosefilmandotorrheaandweretreated withtopical antibiotic therapy. A new return was sched-uledfortwomonthslater,whenallreturningpatientswere asymptomatic.

Discussion

Traumaticperforationofthetympanicmembraneisknown tohave a goodprognosis andspontaneousrecovery, even withouttreatment.2_{However,whileawaitingthehealingof}

themembrane,thepatienthastolivewiththesymptoms causedbytheperforation.Severalstudieshavebeencarried outwiththeobjectiveofcomparingthehealingvelocityof TMin experimentsusing differenttechniques and materi-als,however,noneofthemassessedthepatient’sdegreeof annoyancecausedbythehearinglossortinnitus.Theaim ofthesestudieswasnottodetermineor characterizethe annoyanceexperiencedbypatients.

Theuseofbacterialcellulosefilm(Bionext®)inpatients, coveringthetraumatic perforation ofthe tympanic mem-brane,seemstobeanalternativetreatmenttominimizethis annoyance;ithasshown tobequiteeffective inreducing symptoms.

Alltheevaluatedsymptomsoccurredwithsignificant fre-quencyandintensity,sincesymptomsshowedmeanscores alwayscloseto7; afterthecellulose filmplacement,the improvement of the score given to each symptom was significant, decreasing to mean values close to 2. This improvementconfirmstheefficacyofthismethodtorelieve theannoyancecausedbyperforation.

Thisimprovementofthesubjectiveparameters,assessed bythesymptomscores,wasconfirmedbythemeasurement ofthetonalandwordrecognitionthresholds.Althoughthese audiometricprocedurescanalsobeconsideredsubjective, theirdegreeofsubjectivityislower.

Theauditoryassessmentshowedinitialthresholds rang-ing from 18.54 to 23.33dBHL for low and medium frequencies (250Hz, 500Hz, 1000Hz and 2000Hz), and 24.79---27.50dBHL for high frequencies (4000Hz and 8000Hz).Althoughtheexpectedresultincasesoftympanic membraneperforationisamoreintenselossofconduction at low frequencies,2,8 _{our evaluation of tonal thresholds}

showed a greater loss at high frequencies. One possible explanation is that such patients have suffered, in addi-tiontothetympanicperforation,anacoustictrauma,which couldexplainthealterationatthebaseofthecochlea.

Afterthefilmplacement,animmediateandsignificant improvementin the tonalthresholds wasobserved for all frequencies, except for 8000Hz, showing a recovery of the TM function. This result is similar to that found in the literature. Spandow17 _{and Silverstein}8 _{also evaluated}

thepresence of auditory thresholdalteration after paper patchplacement.Bothfoundmarkedimprovement atlow andmediumfrequencieswithoutsignificantimprovementat highfrequencies(4000Hz).

Somevariablescouldbedeterminantandinterferewith theresultsrelatedtosymptomsandaudiometry,suchasthe sizeoftheperforation.

Thisstudysampleworkwasrelativelyhomogeneous,with perforationsthataffectedonaverage25%oftheTM,withno caseofperforationgreaterthan50%.Asobserved,boththe symptomsandtheirimprovementareunrelatedtothesize oftheperforation,andtreatmentwiththefilmapplication foranyperforation,regardlessofitssize,isindicated.The annoyancecausedbytheseperforationsseemstobemore relatedtothesimplepresenceofTMdiscontinuityandnotto amoreintenseimpairmentofthemiddleearamplification mechanisms(inthiscase,catenaryandhydraulic).

Duringthestudyperiodwehadaconsiderablenumberof patientswhofailedtoreturn,butthisfactdidnotinterfere withthefinalresults, sinceourobjectivewastoevaluate theimmediateresponsetothefilmplacementandnotits evolution in the medium or long term. Despite this fail-ure,ourexperienceshowedthattheprocedureis safe,as onlytwocaseshadcomplications(humidityandgranulations in thetympanicmembrane),whichwere easilycontrolled withafurther30-dayfollow-up.Itcanbeassumedthatthe characteristics ofthe cellulosefilm,such asitsthickness, malleabilityandpermeability,wereadequate for the pro-posed objectivesand contributedtothe patients’clinical recovery.

Generally,theapplicationofbacterialcellulosefilmhas showntobeaninnocuousprocedure,withalow complica-tion rate, well tolerated by the patient and with a clear improvement of the auditory symptoms and thresholds, beingthereforeagoodalternativefortheclinicaltreatment whilewaitingforthetympanicmembranetoheal.

Conclusion

Theuseofabacterialcellulosefilmfragmentontraumatic perforations of the tympanic membrane promoted imme-diatefunctionalandsymptomaticrecoveryintheassessed patients.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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