Anterior Cerebral ArteryInfarction, Anterior Cerebral ArteryCerebral ArteriesIntracranial AneurysmCerebral AngiographyAneurysm, RupturedMiddle Cerebral ArteryCircle of WillisVertebral ArterySubarachnoid HemorrhageBasilar ArteryArteriesCerebral InfarctionCerebral Arterial DiseasesInfarction, Middle Cerebral ArteryCerebrovascular CirculationCerebellumTomography, X-Ray ComputedCerebellar DiseasesEmbolization, TherapeuticPosterior Cerebral ArteryMagnetic Resonance AngiographyCarotid Artery, InternalCerebral RevascularizationUltrasonography, Doppler, TranscranialLateral Medullary SyndromeCarotid ArteriesVertebrobasilar InsufficiencyAngiography, Digital SubtractionIntracranial Arteriovenous MalformationsNeurosurgical ProceduresBrain IschemiaCraniotomyAneurysm, DissectingAkinetic MutismBlood Flow VelocityMagnetic Resonance ImagingBrain Stem InfarctionsIntracranial Embolism and ThrombosisEchoencephalographyVasospasm, IntracranialArterial Occlusive DiseasesSurgical InstrumentsIschemic Attack, TransientPulmonary ArteryHemifacial SpasmBrainVertebral Artery DissectionRupture, SpontaneousBrain Hemorrhage, TraumaticDominance, CerebralTreatment OutcomeIntracranial ArteriosclerosisCerebrovascular DisordersMoyamoya DiseaseRenal ArteryFemoral ArteryMesenteric ArteriesCerebral HemorrhageTrigeminal NeuralgiaUltrasonography, DopplerCaloric TestsCarotid Artery DiseasesRegional Blood FlowVertigoBrain InfarctionCarotid StenosisStrokeCerebellopontine AngleIliac ArteryCoronary Artery BypassRetrospective StudiesCollateral CirculationHematomaRadial ArteryUltrasonographyFacial Nerve DiseasesMicrosurgeryMammary ArteriesFollow-Up StudiesFrontal LobeSubclavian ArteryTemporal ArteriesImaging, Three-DimensionalNerve Compression SyndromesElectronystagmographyCarotid Artery, CommonCerebral PalsyBrachial ArterySplenic ArteryUmbilical ArteriesVasoconstrictionTime FactorsCranial Fossa, PosteriorCranial Nerve DiseasesHepatic ArteryCoronary VesselsOphthalmic ArteryPostoperative ComplicationsCentral Nervous System Vascular Malformations