Post on 06-Nov-2019
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.