Joyce HO, Eugene WONG, Narinder SINGH

Department of Otolaryngology Head and Neck Surgery, Westmead Hospital, Sydney, Australia

Background

•  Chronicmaxillaryatelectasis(CMA)isanunderdiagnosedconditionthatcanoccurbilaterallyandmayleadtosignificantcomplications.

•  Itsaetiologyhasnotbeenestablished.•  Accessorymaxillaryostium(AMO)isadefectinthefontanelleandisassociatedwithmaxillarysinuspathology.•  IthasnotbeenestablishedwhetherAMOisacongenitaloranacquiredstructure.•  WepresentacaseofbilateralCMAinthepresenceofaunilateral(left)AMO.

CasePresentation

•  47-year-oldmalewithalonghistoryofnasalobstructionthatwasworseontheright.

•  Associatedright-sidedmalarandperiorbitalfacialpainandfrontalheadaches.

•  Flexiblenasendoscopydemonstratedarightanteriorseptaldeviationandmarkedlateralisationofbothuncinateprocesses.

•  CTofparanasalsinuses(Figure1)demonstratedfindingsconsistentwithadiagnosisofbilateralstageIICMA.AnAMOcouldalsobeidentifiedontheleft.

•  Patientunderwentseptoplasty,bilateralinferiorturbinoplasty,bilateraluncinectomiesandmaxillaryantrostomies.•  Intraoperatively,theleft-sidedAMOwasidentifiedintheposteriorfontanelle(Figure2)andincorporatedintotheantrostomy.•  At6weeksfollow-up,therewascompleteresolutionofsymptoms.

Discussion

Figure2.Intraoperativeendoscopicviewofleftmiddlemeatusshowinglateralisationofuncinateprocessandaccessorymaxillaryostium.

POSTERNUMBER

P-160

Figure 1. CoronalsliceoftheCTparanasalsinusesdemonstratingseptaldeviationtotheright,bilaterallateralisationofuncinateprocesses(arrows),alargeleftconchabullosa,bowingofthesuperiorosseouswalls(rightmorepronouncedthanleft),opacificationoftherightmaxillarysinusandanearlyretentioncystintheleftmaxillarysinus.

•  CMAhastraditionallybeendescribedasaunilateralcondition.•  Multiplereportsofbilateralpathologyintheliteraturehave

challengedthistraditionaldefinition.•  Maintheoryregardingitsaetiology:

•  Sustainedobstructionatostiomeatalcomplexàmucosalresorptionofsinusgasàdevelopmentofnegativepressurewithinmaxillarysinusesàtriggersprocessofremodellingandinwardbowingofthemaxillarysinuswalls.

•  StudyonrabbitmodelssuggeststhatAMOcanbeacquiredasaresultofapathologicalsituation

•  OurpatienthadbilateralstageIICMAbutonlyhadmaxillarysinusopacificationandsymptomsontherightside.

•  Presenceofacongenital,patentAMOwouldhavelikelypreventedtheinitialbuild-upofnegativeintra-sinuspressure.

•  Therefore,wepostulatethatthepatientinitiallydevelopedCMAbilaterallyfromobstructionoftheostiomeatalcomplex.ThepatientsubsequentlydevelopedleftAMO,orhadapre-existingobstructedorsmallAMOthatbecamepatent,whichthenhaltedtheprogressionofthediseaseontheleftsidebyequalisingthenegativepressuredifferential.•  ThissupportsthatideathatsomeAMOmaybeacquiredanomalies

secondarytosinuspathology.

Conclusion

•  Chronicmaxillaryatelectasiscanoccurbilaterallyandcausesignificantsinonasalsymptoms.•  ThiscasesuggeststhatsomeAMOareacquireddefectsandsupportsthenotionthatCMAiscausedbynegativeintra-

sinuspressures.•  FurtherresearchisrequiredtoestablishthepreciseaetiologyofCMA.