简介：Applicationofsurgicalendoscope,usedaloneorincombinationwiththesurgicalmicroscope,fortheoperativemanagementofearandtemporalboneconditionsmayallowimprovedaccessandclearanceofdisease.Preservationofnormalstructuresmayalsobeimproved.Astheuseofthistoolisincreasing,theneedforbetterunderstandingoftheanatomyoftheearisbecomingevident.Thisisparticularlysoforendoscopicsurgeryaimingatremovaloflesionsinvolvingtheinfra-cochlearcorridorand/orpetrousapex.Humantemporalbone-derivedlabyrinthcasts(molds),originallymadeforendolymphaticductandsacanalysiswhichgenuinelyrepresentthemembranouslabyrinthanditsadjacentsofttissues,weremorphometricallyanalyzedintermsoftheanatomicrelationsbetweenstructuresinandaroundtheinfra-cochlearcorridor.Thedistancebetweenthepetrouscarotidartery(PCA)andthebasalturnofthecochlea,thedistancebetweenPCAandinfra-cochlearvein(ICV)/cochlearaqueduct(CA),andthedistancebetweenthelowersurfaceofbasalcochlearturnandthepointwherethecarotidarteryandjugularvein(JV)meetclosetothejugularforamen,weremeasuredtobearound1.3mm,6mmand8mmrespectively,thusconstitutinganapproximate68mm2infra-cochlearcorridor.Thisanalysisandfurtherstudywithlargersamplesmightbehelpfulforoperationviathiscorridorledtothepetrousapexwherecholesterolgranuloma,cholesteatomaandotherlesionsarenotuncommon.