14TheHearingJournalJune2015CliniCalConsultationA6-year-oldpatienthashadhearinglossononesidesincebirth,failingnewbornhearingscreeningontherightsideandpassingontheleft,thepatient’smothersaid.Thechildhadnoissuesinspeechandlanguagedevelopment,sothemotherdidnotfollowupfur-ther.Thepatientnowistostartschool,however,andarecenthearingscreeningrevealedanearmaximumconductivehearinglossontherightside,withnormalhearingontheleft.Theexaminationofthechildshowsaverynarrowearcanalimpactedwithcerumen.Thecanalappearsasaslitfilledwithdebris.Symptom:UnilateralHearingLossByHamidR.Djalilian,MDDr.DjalilianisdirectorofneurotologyandskullbasesurgeryandassociateprofessorofotolaryngologyandbiomedicalengineeringattheUniversityofCalifornia,Irvine.Whatisyourdiagnosis?Seep.16.Thisistheaudiogramforour6-year-oldpatient,whohashadunilateralhearinglosssincebirth.1252505001K2K4K8K–100102030405060708090100110120HearingLeveldB-ANSIS3.6-20047501.5K3K6KFrequency–Hzaudstudent.com4/23/1511:05PM16TheHearingJournalJune2015CliniCalConsultationwhohavecongenitalstenosisthaninthosewithcompleteatresia.Treatmentofchildrenwithcongenitalstenosisoftheexter-nalauditorycanalcanincludeamplificationorsurgery,de-pendingontheparents’preference.Whileair-conductionhearingaidscanbeattemptedinthesepatients,theverysmallnatureoftheearcanalpre-cludesobtainingapropermold,makingtheoptionlesssuc-cessful.Traditionalbone-conductionhearingaidscanbeused,thoughthesedeviceshavegivenwaytosoftbandbone-conductiondevices.Softbandbone-conductiondevices,suchasSo-phono,Ponto,orBaha,canlaterbeemployedforrehabilitationiftheparentsoptforabone-conductionContinuedfromp.14Inachild,unilateralhearinglosscancausedifficultiesinschoolperformance.Theconditionleadstoproblemswithspeechunderstandinginnoisyenvironments,suchasclassroomdiscussions,aswellaslocalizationofsound.Consequently,theidentificationandmanagementofpatientswithunilateralhearinglossisofsignificantimpor-tance.Mostcommonly,unilateralconductivehearinglossinchil-drenisduetomiddleeareffusionafteranupperrespiratorytractinfectionoracuteotitismedia.However,significantcon-ductivehearingloss(greaterthana30-dbair-bonegapinthepure-toneaverage)wouldberarefromjustmiddleeareffu-sion.Therefore,inthepresenceofsignificantconductivehearingloss,furtherfollow-upisnecessarytoevaluatehear-ingafterresolutionofthemiddleeareffusion.Largeconductivehearinglossisseeninchildrenwithos-sicularfixation,densecerumenimpaction,tympanicmem-braneperforation,congenitalatresiaoftheearcanal,andcongenitalstenosisoftheexternalauditorycanal,amongotherconditions.aMPliFiCationVssuRGERYOurpatienthadcongenitalstenosisoftheexternalauditorycanal.Theexternalauditorycanaldevelopsinthe18thweekofgestation,longafterthedevelopmentoftheinnerearstruc-tures,whichstartsinthefourthweek.Asaresult,congenitalabnormalitiesoftheearcanalareveryrarelyassociatedwithamalformationoftheinnerear.Congenitalatresiaoftheearcanalisacompleteblockageoftheexternalauditorycanal,whilecongenitalstenosisisasignificantnarrowingofthecanal.Generally,anearcanalisconsideredstenoticifitsdiameterislessthan4mm.Patientswithcongenitalstenosisoftheearcanalhavevaryingmiddleearabnormalities,suchasahypoplastictym-panicmembrane,tympanicmembranenotconnectedtotheossicularchain,fixedossicularchain,andfusedmalleus–incuscomplex.Thestapesgenerallyisnormal,asitisembryologi-callyderivedfromthesecondbr...
