Angiography, Digital SubtractionSubtraction TechniqueMagnetic Resonance AngiographyCerebral AngiographyAngiographyIntracranial AneurysmCoronary AngiographyRadiographic Image EnhancementImaging, Three-DimensionalContrast MediaIntracranial Arteriovenous MalformationsTomography, X-Ray ComputedEmbolization, TherapeuticSensitivity and SpecificityCarotid Artery, InternalImage Processing, Computer-AssistedAneurysm, RupturedCentral Nervous System Vascular MalformationsArterial Occlusive DiseasesCarotid StenosisSubarachnoid HemorrhageTomography, Spiral ComputedCerebral VeinsIohexolSalivary Gland CalculiReproducibility of ResultsFluorescein AngiographyIopamidolUltrasonography, Doppler, DuplexObserver VariationConstriction, PathologicUltrasonography, Doppler, ColorRadiographic Image Interpretation, Computer-AssistedRadiography, Dental, DigitalArteriovenous MalformationsCerebral ArteriesVertebrobasilar InsufficiencyX-Ray Intensifying ScreensArtifactsCarotid Artery DiseasesPredictive Value of TestsGadolinium DTPAAnterior Cerebral ArteryMagnetic Resonance ImagingTriiodobenzoic AcidsCarotid-Cavernous Sinus FistulaVertebral ArteryTibial ArteriesRetrospective StudiesSurgical InstrumentsProspective StudiesCranial SinusesVasospasm, IntracranialCerebrovascular DisordersImage EnhancementBasilar ArteryRadiography, InterventionalUltrasonography, Doppler, TranscranialInjections, Intra-ArterialArteriovenous FistulaAneurysmSialographyTreatment OutcomeMyelographyCerebrovascular CirculationCircle of WillisCerebral RevascularizationRenal ArteryIothalamate MeglumineCarotid ArteriesIntracranial ArteriosclerosisNeurosurgical ProceduresSalivary Gland DiseasesRadiation DosageFeasibility StudiesBlood Flow VelocityRadiography, BitewingCarotid Artery, ExternalFollow-Up StudiesMoyamoya DiseaseRadionuclide AngiographyVascular PatencyPhantoms, ImagingStentsCollateral CirculationAortographyUltrasonographyAngioplasty, BalloonGadoliniumSialadenitisImmediate Dental Implant LoadingIschemic Attack, TransientUltrasonography, DopplerTime FactorsPopliteal ArteryCerebrospinal Fluid RhinorrheaEndarterectomyBrain IschemiaSeverity of Illness IndexCeliac Artery