Carotid Artery, InternalVertebral ArteryCarotid ArteriesCarotid Artery DiseasesCarotid StenosisVertebral Artery DissectionCerebral AngiographyCarotid Artery, ExternalCarotid Artery, CommonCarotid Artery, Internal, DissectionCircle of WillisCarotid Artery ThrombosisEndarterectomy, CarotidVertebrobasilar InsufficiencyArteriesCerebral ArteriesMagnetic Resonance AngiographyAngiography, Digital SubtractionArterial Occlusive DiseasesIntracranial AneurysmBasilar ArteryCerebrovascular CirculationAngiographyTomography, X-Ray ComputedUltrasonography, Doppler, DuplexIschemic Attack, TransientCerebral RevascularizationSubclavian ArteryCollateral CirculationCerebrovascular DisordersAneurysmStentsUltrasonography, Doppler, TranscranialEmbolization, TherapeuticCerebral InfarctionBlood Flow VelocityIntracranial Embolism and ThrombosisCavernous SinusEndarterectomyIntracranial ArteriosclerosisBrain IschemiaOphthalmic ArteryFibromuscular DysplasiaCarotid Artery InjuriesUltrasonography, Doppler, ColorPulmonary ArteryMiddle Cerebral ArteryAneurysm, RupturedUltrasonographySubarachnoid HemorrhageStrokeMoyamoya DiseaseAngioplasty, BalloonAneurysm, DissectingTreatment OutcomeCarotid-Cavernous Sinus FistulaTunica IntimaFemoral ArterySubclavian Steal SyndromeDoppler EffectBalloon OcclusionIntracranial EmbolismAneurysm, FalseAngioplastyConstriction, PathologicNeck InjuriesTunica MediaRegional Blood FlowRenal ArteryTemporal ArteriesMagnetic Resonance ImagingArteriosclerosisMesenteric ArteriesEpistaxisPetrous BoneFollow-Up StudiesCranial Nerve DiseasesUltrasonography, DopplerSphenoid BoneCatheterizationCerebral Arterial DiseasesCarotid BodyProspective StudiesTime FactorsAmaurosis FugaxInjections, Intra-ArterialBrainMammary ArteriesRetrospective StudiesRadial ArteryHorner SyndromeLateral Medullary SyndromeCarotid SinusRisk FactorsEchoencephalographyCoronary Artery BypassAnterior Cerebral ArteryIliac ArterySensitivity and SpecificityCarotid Intima-Media Thickness