Basilar ArteryPeriventricular Nodular HeterotopiaVertebrobasilar InsufficiencyLens SubluxationMagnetic Resonance ImagingPosterior Cerebral ArteryVertebral ArteryInfarction, Posterior Cerebral ArteryBrain MappingCerebral AngiographyIntracranial AneurysmBrain Stem InfarctionsCerebral ArteriesBrainImage Processing, Computer-AssistedArteriesCerebral CortexSubarachnoid HemorrhageMagnetic Resonance AngiographyCerebrovascular CirculationBrain InfarctionAneurysm, RupturedCerebral InfarctionIntracranial ArteriosclerosisEmbolization, TherapeuticMoyamoya DiseaseVertebral Artery DissectionStrokeCarotid Artery, InternalAnterior Cerebral ArteryTomography, X-Ray ComputedBrain IschemiaUltrasonography, Doppler, TranscranialPulmonary ArteryIschemic Attack, TransientIntracranial EmbolismAngiography, Digital SubtractionArterial Occlusive DiseasesCarotid ArteriesTreatment OutcomeAngiographyCerebrovascular DisordersAneurysm, DissectingCerebral RevascularizationRetrospective StudiesVasospasm, IntracranialConstriction, PathologicMesenteric ArteriesFemoral ArteryRenal ArteryVasodilationFollow-Up StudiesBlood CirculationAcute DiseaseVasoconstrictionCranial Fossa, PosteriorStentsCerebellumProspective StudiesMuscle, Smooth, VascularDogsRisk FactorsCoronary Artery BypassIliac ArteryRegistriesVasodilator AgentsRadial ArteryRecurrenceMammary ArteriesCarotid Artery DiseasesMiddle Cerebral ArterySerotoninPredictive Value of TestsSubclavian ArteryCircle of WillisPulmonary CirculationDiffusion Magnetic Resonance ImagingCoronary VesselsExtracorporeal CirculationRabbitsBrachial ArterySplenic ArteryCollateral CirculationVasoconstrictor AgentsPapaverineMuscle ContractionPotassium ChlorideEndothelium, VascularRegional Blood FlowHepatic ArteryCarotid Artery, CommonTime FactorsOphthalmic ArteryAcetylcholinePicolinesSumatriptanCoronary CirculationCeliac ArteryIntracranial Embolism and ThrombosisMesenteric Artery, Superior