Page 151 - Demo

Augmentedrealityguidedcondylectomy1499INTRODUCTIONUnilateralcondylarhyperplasia(UCH)isararedisorderofprogressivenatureandischaracterizedbyalterationstofacialfunctionandaesthetics12UCHiscausedbyanoveractivegrowthactivityinoneofthemandibularcondylesbutitsaetiologyisstilluncertainandisprobablymultifactorial3ProportionalcondylectomyisincreasinglybeingusedasaninitialtreatmentinUCH4andisaimedtoenhancethesymmetryofthemandibleandocclusalplanebylocatingtheheightoftheosteotomylineinsuchawaythattheramusheightoftheaffectedsidematchesthenon-affectedside ThekeyinproportionalcondylectomyistobeabletoplacetheosteotomyplaneatthedesiredlocationTheoptimalheightandpositionofthecondylarosteotomylinecanbeplannedbyusinga3Dreconstructedvirtualskullmodelbasedonaconebeamcomputedtomography(CBCT)scanClinicallyitremainschallengingtotransferavirtuallyplannedcondylectomyplanetothepatient during surgery Thelimited surgical access the axiallocation of the condylarheadandtheseatingofcondyleinthefossaoftenrestrictsacompleteoverviewofthecondylarheadandhamperstheuseofsurgicalguides Theimplementationofaugmentedreality(AR)canaidsurgicalinterventionsbypresentingimagesof3Dvirtualsurgicalplanningontheoperationfield5 WepresentanovelAR-guidedworkflowforcondylectomyMATERIAL&METHODA38-year-oldfemalepresentedatourdepartmentwithaprogressivechinpointdeviationtotherightbasedonanunilateralcondylarhyperplasiaAproportionalcondylectomyoftheleftcondylewasproposedA threshold-based segmentation inIPS CaseDesigner (KLS Martin Group TuttlingenGermany)wasusedtocreatea3DmodelofthemandiblefromanextendedheightCBCTscan(FOV16×22cm;scanningtime2×20s;voxelsize04mm;3DImagingSystemImagingSciencesInternationalIncHatfieldPAUSA)Theosteotomyplanewasvirtuallyplannedtoresolvethediscrepancybetweentheleftandrightramalheight