Angiography, Digital SubtractionSubtraction TechniqueMagnetic Resonance AngiographyCerebral AngiographyAngiographyIntracranial AneurysmCoronary AngiographyRadiographic Image EnhancementImaging, Three-DimensionalContrast MediaIntracranial Arteriovenous MalformationsTomography, X-Ray ComputedSensitivity and SpecificityEmbolization, TherapeuticCarotid Artery, InternalImage Processing, Computer-AssistedReproducibility of ResultsAneurysm, RupturedCentral Nervous System Vascular MalformationsArterial Occlusive DiseasesCarotid StenosisSubarachnoid HemorrhageTomography, Spiral ComputedCerebral VeinsObserver VariationIohexolSalivary Gland CalculiFluorescein AngiographyIopamidolUltrasonography, Doppler, DuplexRadiographic Image Interpretation, Computer-AssistedUltrasonography, Doppler, ColorConstriction, PathologicRadiography, Dental, DigitalPredictive Value of TestsArteriovenous MalformationsCerebral ArteriesArtifactsX-Ray Intensifying ScreensVertebrobasilar InsufficiencyProspective StudiesGadolinium DTPACarotid Artery DiseasesMagnetic Resonance ImagingRetrospective StudiesAnterior Cerebral ArteryTreatment OutcomeTriiodobenzoic AcidsCarotid-Cavernous Sinus FistulaVertebral ArteryImage EnhancementTibial ArteriesSurgical InstrumentsCerebrovascular DisordersCranial SinusesUltrasonography, Doppler, TranscranialVasospasm, IntracranialRadiography, InterventionalBasilar ArteryInjections, Intra-ArterialArteriovenous FistulaAneurysmSialographyCerebrovascular CirculationMyelographyFeasibility StudiesFollow-Up StudiesCircle of WillisCarotid ArteriesRenal ArteryBlood Flow VelocityCerebral RevascularizationTime FactorsNeurosurgical ProceduresRadiation DosageIothalamate MeglumineIntracranial ArteriosclerosisSeverity of Illness IndexSalivary Gland DiseasesRisk AssessmentRadiography, BitewingCarotid Artery, ExternalUltrasonographyRadionuclide AngiographyPhantoms, ImagingMoyamoya DiseaseVascular PatencyStentsCollateral CirculationAortographyUltrasonography, DopplerGadoliniumAngioplasty, BalloonPreoperative CareSialadenitisIschemic Attack, TransientImmediate Dental Implant LoadingCoronary Artery DiseasePopliteal ArteryBrain Ischemia