Braz. j. . vol.81 número2

BrazJOtorhinolaryngol.2015;81(2):226---227

www.bjorl.org

Brazilian

Journal

of

OTORHINOLARYNGOLOGY

CASE

REPORT

Rare

case

of

neurinoma

of

the

facial

nerve

夽

,

夽夽

Caso

raro

de

neurinoma

do

nervo

facial

Ivna

Mota

Passos

,

Eduardo

Tanaka

Massuda

,

Miguel

Angelo

Hyppolito

,

Benedicto

Oscar

Colli

_,

_Thiago

_Augusto

_Damico

a_{HospitaldasClínicasdaFaculdadedeMedicinadeRibeirãoPreto,UniversidadedeSãoPaulo(USP),RibeirãoPreto,SP,Brazil} b_{FaculdadedeMedicinadeRibeirãoPreto,UniversidadedeSãoPaulo(USP),RibeirãoPreto,SP,Brazil}

Received8September2014;accepted9December2014 Availableonline15January2015

Introduction

Facialnerveneurinomais arare entity,although of great interest, especially from the point of view of the differ-ential diagnosis of the causes of peripheral facial palsy.1

Neurinomasarebenigntumors,derivedfromSchwanncells. Theymanifestmainlyasperipheralfacialpalsy,whichcan beslow,graduallyaffectingseveralnervebranches,orwith asuddenonset.1,2_{Theyprogressivelyinvadethemiddleear}

andtheposteriorwalloftheexternalauditorycanal,causing lossofauditoryacuity.1,2

Facialnerveneurinomahasanincidenceof0.15---0.8%.2---4

Recentstudies suggest that themost common anatomical locationwouldbeinthetympanicandverticalnerve path-way,butmorerecentstudieshaveobserveditspresencein thegeniculateganglion.2,4

Advancedcurrent radiological techniques, mainly high-resolution computed tomography (CT) and magnetic

夽 _{Pleasecitethisarticleas:PassosIM,MassudaET,HyppolitoMA,}

ColliBO,DamicoTA.Rarecaseofneurinomaofthefacialnerve. BrazJOtorhinolaryngol.2015;81:226---7.

夽夽_{Institution:HospitaldasClínicasdaFaculdadedeMedicinade}

RibeirãoPreto,UniversidadedeSãoPaulo(USP),RibeirãoPreto,SP, Brazil.

∗_{Correspondingauthor.}

E-mail:ivnamota@hotmail.com(I.M.Passos).

resonance imaging (MRI),3 _{have provided an earlier}

diag-nosis. The advent of MRI had a significant impacton the diagnosis and management of neurinomas of the facial nerve,asinadditiontotheearlydiagnosis,thereisgreater accuracyregardingthelimitsandextentoflesions.3

Inthis reporttheaim wastoreport theoccurrence of a facial neurinoma located near the geniculate ganglion, althoughitwasunaffected.

Case

presentation

Amalepatient,28yearsold,reportedlabialdeviationtothe leftsincechildhood,progressinginthelasteightmonthsto palsyintheupperthirdoftheface,perceivedduring medi-cal assessment. He has had hearingloss and intermittent tinnitusontheleftfortwoyears.

Otorhinolaryngological assessment showed Grade II House-Brackmann(HB)facialpalsytotheleft.MRIshowed extensive formations in the topography of the left facial nervecanalnearthegeniculateganglion,withhyposignalon T1andhyperintenseonT2,suggestiveoffacialnerve neuri-noma.Treatmentoptionswerediscussedwiththepatient, whodecidedtoselectclinicalfollow-up.

Aftertwoyearsoffollow-uphedevelopedworseningof peripheral facial palsy, HB grade IV, and the MRI showed increasedvolumeofthelesionincomparisontotheprevious assessment, measuring 1.7×1.3cm (Fig. 1), compressing

thelowertemporalgyrus.

http://dx.doi.org/10.1016/j.bjorl.2014.12.008

Rarecaseofneurinomaofthefacialnerve 227

Figure1 AxialT1-weightedmagneticresonanceimagingwith contrastshowinglesionlocatednexttothegeniculateganglion andtympanicportionofthefacialnervetotheleft.

Thechoiceofsurgicalapproachwasdecided,considering thefindingsandneurosurgeryteamassessment.

Puretoneaudiometryshowedmoderateconductiveloss to the left and normal hearing to the right. Impedance audiometryresultedincurvetypeA,bilaterally. Electromyo-graphywascompatiblewithpartiallesionoftheleftfacial nerve,demonstratingsevereintensityandsignsofactivity withoutfibrillation.CTscanofthetemporalbonesshoweda massinthetympanicregionofthefacialnerve,compressing theossicles. Tegmenerosionwasobserved,withprobable maintenanceofduramater.

The patientunderwentsurgery,whichunveiledalesion intheprojectionofthegeniculateganglion inthepetrous portionofthetemporalbone,withextraduralextensionthat wassoft,poorlyvascularized,andextendingtothemastoid facialcanal.Presenceofviablefacialnervenearthe stylo-mastoidforamenwasobserved.Thelesionwasresectedand greaterauricularnervegraftingwasperformed.

ThepatientpersistedwithGradeIVparalysis postopera-tively.Histopathologicalexaminationdisclosedthepresence ofcellschwannoma,withgeniculateganglionfreeof neo-plasticinvolvement.

Discussion

Themanagementoffacialneurinomaisadelicateprocess. Therapeutic options include clinical observation, surgical resection,andradiotherapy.4

Currently,surgicalresectionisreservedforpatientswith poorfacialnervefunction,House-BrackmannIII,orworse. Inpatientswithgoodfunction,HBIorII,clinicalfollow-up canbe optedinitially, combinedwithimaging follow-up.4

Radiationtherapy isonlyindicatedforpatientswithHBIII orworse,withunfavorableclinicalconditionsforsurgery.4

In this case, the authors initially observed good facial nervefunction(HBII),andthus,clinicalandimaging follow-up were initially chosen. Due to the progression of the lesion, both in volumesize and clinical worsening of the facialnerve function (HB IV) during twoyears of follow-up,itwasdecidedtoperformsurgicalresectionandgreater auricularnervegrafting, withnervefunctionmaintenance (HBIV).

Final

comments

Earlysurgical intervention is recommendedin the follow-ingcases:intratemporaltumorsextending tothe parotid, tumors with multiple segments extending to the cere-bellopontine angle and middle fossa, rapidly growing lesions, or those showing compression of the temporal lobe.4

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

References

1.LopesOC,CastroNPJr,PialarissiPR.Neurinomadonervofacial. BrazJOtorhinolaryngol.1977;43:46---53.

2.ShernaJD, DagnewE,PensakML,vanLoverenHR,TewJMJr. Facialnerve neuromas: reportof 10cases and review ofthe literature.Neurosurgery.2002;50:450---6.

3.Kertesz TR, Shelton C, Wiggins RH, Salzman KL, Glaston-buryCM, HarnsbergerR. Intratemporal facialnerve neuroma: anatomical location and radiological features. Laryngoscope. 2001;111:1250---6.