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Objective:Toinvestigate theimpactofSSF-anovelvendor-specificmotion-correctionalgorithmonimagequalityofcoronary arteryincardiacphantomundergoingcoronaryCTangiography,withassessmentoftheinfluenceofheartrate,contrastagent concentration,tubevoltageandAsiRratio. Materials and methods:Acardiacbeatingphantomfilledwith3differentconcentrationcontrastagent(650HU,450HU,250HU) wasunderwentcoronaryCTangiographywith16cm-detectorCTscanner,applyingdifferenttubevoltages(70kV, 80kV,100kV,120kV)andheartrate(60-130bpm).ThescanwasECG-gatedandprospectivelytriggered.Allimagesacquiredwith 80bpm,120kV,375mAwerereconstructedusingdifferentAsiRratio(0%,30%,50%,70%).Additionally,theaverageCTvalueof phantomventricleandthesurroundingliquidwasrecordandcalculated.Thesignaltonoiseratio(SNR)andnoiseofimages reconstructedwithdifferentAsiRratioswerecompared.Manymimicalrightcoronaryarterieswithsmalldiameter(1mm)andtwo leftcoronaryarterieswithlargediameter(4mm)onthephantomwereanalyzed.Theimagequalityofcoronaryarterywas definedaccordingtothefour-scoreclassificationsystem(1,excellentwithoutartifactsrelatedtomotion;2,minorartifact;3, considerableartifactsbutmaintainedvisualizationofarteriallumen;4,non-diagnosticduetoseveremotionartifacts).The proximalanddistalsegmentsofphantomwerevisuallyscoredbyaradiologistwithrichexperience.Theinfluenceofheartrate, contrastagentconcentration,tubevoltageandAsiRratioonSSFtoimagequalitywasassessedbytendencychart. Results:Forthemimicalrightcoronaryarteries,theSSFalgorithmimprovestheimagequalityirrespectiveoftheheartratefrom 60-130bpmandcontrastagentconcentration(650HU,450HU,250HU).While,theimagequalityofmimicalleftarterywith relativelargediameteronlyimproveinthecaseofHR60-70bpmandcontrastagentconcentration650HU.TheSNRandnoise haveapositiveandnegativerelationshipwithAsiRratiorespectively,irrespectiveoftheheartrate(60-90bpm)andcontrastagent concentration(650HU,450HU,250HU).TheAsiRratiohascontributedtotheimprovementofimagequalitybySSFinthecaseof higherheartrate(80-90bpm)andlowercontrastagentconcentrationforbothrightandleftcoronary.Highertubevoltagehasno contributiontotheimprovementofcoronaryarteryimagequalityamongthreedifferentcontrastagentconcentrationgroups. Conclusion:Formimicalrightcoronarywithrelativesmalldiameter(about1mm),highcontrastagentconcentrationandhighAsiR ratiowillaidSSFtoacquirebetterimagequalityofcoronaryartery,especiallyinthosewithhigherheartrate(90-130bpm).