Angiography, Digital SubtractionSubtraction TechniqueMagnetic Resonance AngiographyCerebral AngiographyAngiographyIntracranial AneurysmRadiographic Image EnhancementCoronary AngiographyImage Processing, Computer-AssistedImaging, Three-DimensionalContrast MediaTomography, X-Ray ComputedIntracranial Arteriovenous MalformationsSensitivity and SpecificityEmbolization, TherapeuticCarotid Artery, InternalAneurysm, RupturedReproducibility of ResultsRadiographic Image Interpretation, Computer-AssistedCentral Nervous System Vascular MalformationsArterial Occlusive DiseasesTomography, Spiral ComputedCarotid StenosisSubarachnoid HemorrhageCerebral VeinsIohexolObserver VariationSalivary Gland CalculiFluorescein AngiographyIopamidolUltrasonography, Doppler, DuplexUltrasonography, Doppler, ColorConstriction, PathologicX-Ray Intensifying ScreensImage Interpretation, Computer-AssistedRadiography, Dental, DigitalGadolinium DTPAArteriovenous MalformationsCerebral ArteriesVertebrobasilar InsufficiencyPredictive Value of TestsArtifactsCarotid Artery DiseasesAnterior Cerebral ArteryRetrospective StudiesTriiodobenzoic AcidsMagnetic Resonance ImagingProspective StudiesVertebral ArteryCarotid-Cavernous Sinus FistulaSurgical InstrumentsTibial ArteriesCerebrovascular DisordersRadiography, InterventionalCranial SinusesVasospasm, IntracranialBasilar ArteryUltrasonography, Doppler, TranscranialInjections, Intra-ArterialImage EnhancementArteriovenous FistulaAneurysmTreatment OutcomeSialographyAlgorithmsMyelographyFeasibility StudiesCerebrovascular CirculationCircle of WillisCarotid ArteriesNeurosurgical ProceduresCerebral RevascularizationRenal ArteryIothalamate MeglumineIntracranial ArteriosclerosisSalivary Gland DiseasesBlood Flow VelocityRadiography, BitewingRadiation DosageUltrasonographyFollow-Up StudiesCarotid Artery, ExternalMoyamoya DiseaseGadoliniumTime FactorsRadionuclide AngiographyVascular PatencyStentsEquipment DesignAortographyCollateral CirculationPhantoms, ImagingAngioplasty, BalloonSialadenitisUltrasonography, DopplerIschemic Attack, TransientImmediate Dental Implant LoadingFluoroscopyPopliteal ArterySeverity of Illness Index