Posterior Cerebral ArteryInfarction, Posterior Cerebral ArteryBasilar ArteryCerebral ArteriesVertebrobasilar InsufficiencyCerebral AngiographyVertebral ArteryCircle of WillisCerebral InfarctionIntracranial AneurysmCerebrovascular CirculationMiddle Cerebral ArteryAnterior Cerebral ArteryCerebral Arterial DiseasesMagnetic Resonance AngiographyHemianopsiaUltrasonography, Doppler, TranscranialArteriesAneurysm, RupturedInfarction, Middle Cerebral ArterySubarachnoid HemorrhageEmbolization, TherapeuticTomography, X-Ray ComputedBrain IschemiaMoyamoya DiseaseMagnetic Resonance ImagingCarotid Artery, InternalIntracranial ArteriosclerosisArterial Occlusive DiseasesBrain Stem InfarctionsBrainAngiography, Digital SubtractionOccipital LobeBrain InfarctionBlood Flow VelocityStrokeCerebrovascular DisordersCerebral RevascularizationDyslexia, AcquiredIschemic Attack, TransientPulmonary ArteryOphthalmoplegic MigraineCarotid ArteriesTreatment OutcomeVasoconstrictionCollateral CirculationTonic PupilEchoencephalographyIntracranial Arteriovenous MalformationsAmobarbitalAnisocoriaOculomotor Nerve DiseasesRetrospective StudiesVasodilationVertebral Artery DissectionMesenteric ArteriesFemoral ArteryEclampsiaRenal ArteryFollow-Up StudiesMuscle, Smooth, VascularHemiplegiaIntracranial Embolism and ThrombosisDominance, CerebralConstriction, PathologicRegional Blood FlowIntracranial EmbolismAngiographyCranial Fossa, PosteriorVasospasm, IntracranialCarotid StenosisBlood PressureAcute DiseaseCoronary Artery BypassIliac ArteryCarotid Artery DiseasesRadial ArteryImage Processing, Computer-AssistedMammary ArteriesAneurysm, DissectingTime FactorsSubclavian ArteryThalamusProspective StudiesTemporal ArteriesTemporal LobeStentsDogsVasodilator AgentsReference ValuesCarotid Artery, CommonUmbilical ArteriesCoronary VesselsCerebral PalsyBrachial ArterySplenic ArteryRats, Sprague-DawleyOphthalmic ArteryCerebellumInfarction, Anterior Cerebral Artery