Magnetic Resonance AngiographyMagnetic Resonance ImagingAngiography, Digital SubtractionContrast MediaAngiographyCerebral AngiographyImaging, Three-DimensionalGadoliniumCoronary AngiographyGadolinium DTPAMagnetic Resonance SpectroscopySensitivity and SpecificityImage EnhancementCircle of WillisTomography, X-Ray ComputedUltrasonography, Doppler, DuplexCarotid StenosisIntracranial AneurysmCarotid Artery, InternalArterial Occlusive DiseasesCerebral Arterial DiseasesConstriction, PathologicArtifactsImage Interpretation, Computer-AssistedRenal Artery ObstructionVertebral ArteryVertebrobasilar InsufficiencyPredictive Value of TestsObserver VariationCerebral ArteriesMagnetic Resonance Imaging, CineReproducibility of ResultsImage Processing, Computer-AssistedAnterior Cerebral ArteryPosterior Cerebral ArteryOrganometallic CompoundsProspective StudiesMeglumineIntracranial Arteriovenous MalformationsIntracranial Arterial DiseasesPulmonary VeinsRenal ArteryEndarterectomy, CarotidCerebrovascular CirculationPreoperative CareCarotid ArteriesIntracranial ArteriosclerosisUltrasonography, Doppler, ColorCollateral CirculationBrainRetrospective StudiesInfarction, Posterior Cerebral ArteryUltrasonography, Doppler, TranscranialSeverity of Illness IndexFeasibility StudiesTreatment OutcomeTibial ArteriesCoronary VesselsPeripheral Vascular DiseasesScimitar SyndromeAneurysm, RupturedBlood Flow VelocityVertebral Artery DissectionEmbolization, TherapeuticPortographyBasilar ArteryUltrasonography, DopplerMoyamoya DiseaseVascular MalformationsCerebrovascular DisordersCarotid Artery DiseasesFluorescein AngiographyFibromuscular DysplasiaStentsLegRadiographic Image EnhancementDiagnostic ImagingLateral Medullary SyndromeTime FactorsPhlebographyCarotid Artery, ExternalAortographyFollow-Up StudiesStrokeIliac ArteryEcho-Planar ImagingIncidental FindingsCerebral VeinsCeliac ArteryBrain IschemiaIschemic Attack, TransientVascular PatencyCoronary Artery DiseaseMiddle Cerebral ArteryHypertension, RenovascularVasculitis, Central Nervous SystemTakayasu ArteritisSingle-Blind MethodAortic Aneurysm, ThoracicCerebral Revascularization