Anterior Cerebral ArteryInfarction, Anterior Cerebral ArteryIntracranial AneurysmCerebral ArteriesCerebral AngiographyVertebral ArteryAneurysm, RupturedCerebellumCerebellar DiseasesSubarachnoid HemorrhageLateral Medullary SyndromeBasilar ArteryArteriesMiddle Cerebral ArteryPosterior Cerebral ArteryBrain Stem InfarctionsCerebral InfarctionVertebrobasilar InsufficiencyCircle of WillisEmbolization, TherapeuticTomography, X-Ray ComputedHemifacial SpasmVertebral Artery DissectionCerebral RevascularizationCerebral Arterial DiseasesMagnetic Resonance AngiographyInfarction, Middle Cerebral ArteryCerebrovascular CirculationAneurysm, DissectingRupture, SpontaneousCraniotomyAngiography, Digital SubtractionCaloric TestsIntracranial Arteriovenous MalformationsNeurosurgical ProceduresMagnetic Resonance ImagingVertigoCarotid Artery, InternalCerebellopontine AngleUltrasonography, Doppler, TranscranialFacial Nerve DiseasesCarotid ArteriesTrigeminal NeuralgiaMicrosurgeryBrain IschemiaAkinetic MutismBlood Flow VelocityBrain InfarctionCranial Fossa, PosteriorIntracranial Embolism and ThrombosisEchoencephalographyTreatment OutcomeArterial Occlusive DiseasesVasospasm, IntracranialSurgical InstrumentsIschemic Attack, TransientCentral Nervous System Vascular MalformationsBrainNerve Compression SyndromesPulmonary ArteryBrain Hemorrhage, TraumaticDominance, CerebralIntracranial ArteriosclerosisCerebrovascular DisordersRenal ArteryMoyamoya DiseaseFemoral ArteryMesenteric ArteriesCerebral HemorrhageUltrasonography, DopplerVena Cava, InferiorCarotid Artery DiseasesRegional Blood FlowMedulla OblongataCarotid StenosisRetrospective StudiesStrokeIliac ArteryFrontal LobeCoronary Artery BypassCollateral CirculationHematomaUltrasonographyRadial ArteryFollow-Up StudiesMammary ArteriesImaging, Three-DimensionalInferior ColliculiSubclavian ArteryTemporal ArteriesTime FactorsElectronystagmographyCarotid Artery, CommonSplenic ArteryCerebral PalsyUmbilical ArteriesBrachial ArteryVasoconstrictionCranial Nerve DiseasesPostoperative Complications