Magnetic Resonance AngiographyMagnetic Resonance ImagingAngiography, Digital SubtractionContrast MediaSensitivity and SpecificityAngiographyImaging, Three-DimensionalCerebral AngiographyGadoliniumCoronary AngiographyGadolinium DTPAReproducibility of ResultsImage EnhancementPredictive Value of TestsTomography, X-Ray ComputedMagnetic Resonance SpectroscopyROC CurveObserver VariationImage Interpretation, Computer-AssistedCircle of WillisUltrasonography, Doppler, DuplexCarotid StenosisIntracranial AneurysmArtifactsArterial Occlusive DiseasesCarotid Artery, InternalProspective StudiesImage Processing, Computer-AssistedConstriction, PathologicCerebral Arterial DiseasesMagnetic Resonance Imaging, CineRenal Artery ObstructionVertebral ArteryVertebrobasilar InsufficiencyCerebral ArteriesMeglumineOrganometallic CompoundsRetrospective StudiesDiagnostic ImagingAnterior Cerebral ArteryPosterior Cerebral ArteryRadiographic Image EnhancementSeverity of Illness IndexPreoperative CareUltrasonography, Doppler, ColorIntracranial Arteriovenous MalformationsPulmonary VeinsIntracranial Arterial DiseasesRenal ArteryTime FactorsBrainFeasibility StudiesUltrasonography, DopplerCerebrovascular CirculationEndarterectomy, CarotidCarotid ArteriesTreatment OutcomeAlgorithmsIntracranial ArteriosclerosisFalse Positive ReactionsCoronary VesselsCollateral CirculationCoronary Artery DiseaseUltrasonography, Doppler, TranscranialInfarction, Posterior Cerebral ArteryFollow-Up StudiesMultidetector Computed TomographyPeripheral Vascular DiseasesBlood Flow VelocityTibial ArteriesAneurysm, RupturedScimitar SyndromeVertebral Artery DissectionEmbolization, TherapeuticPortographySingle-Blind MethodCerebrovascular DisordersBasilar ArteryMoyamoya DiseaseVascular MalformationsCarotid Artery DiseasesFluorescein AngiographyLegUltrasonographyStentsFibromuscular DysplasiaPhlebographyLateral Medullary SyndromeStrokeCarotid Artery, ExternalAortographyEcho-Planar ImagingIncidental FindingsIliac ArteryDiagnostic ErrorsCerebral VeinsCeliac ArteryBrain IschemiaArea Under CurveReagent Kits, Diagnostic