Anterior Cerebral ArteryInfarction, Anterior Cerebral ArteryMeningesCerebral ArteriesTuberculosis, MeningealIntracranial AneurysmCerebral AngiographyAneurysm, RupturedMiddle Cerebral ArteryMagnetic Resonance ImagingCircle of WillisVertebral ArterySubarachnoid HemorrhageBasilar ArteryArteriesCerebral InfarctionCerebral Arterial DiseasesInfarction, Middle Cerebral ArteryCerebrovascular CirculationTomography, X-Ray ComputedCerebellumCerebellar DiseasesEmbolization, TherapeuticPosterior Cerebral ArteryMagnetic Resonance AngiographyCarotid Artery, InternalCerebral RevascularizationUltrasonography, Doppler, TranscranialLateral Medullary SyndromeCarotid ArteriesVertebrobasilar InsufficiencyAngiography, Digital SubtractionIntracranial Arteriovenous MalformationsNeurosurgical ProceduresBrain IschemiaCraniotomyAneurysm, DissectingAkinetic MutismBlood Flow VelocityBrain Stem InfarctionsIntracranial Embolism and ThrombosisEchoencephalographyVasospasm, IntracranialArterial Occlusive DiseasesSurgical InstrumentsIschemic Attack, TransientBrainPulmonary ArteryHemifacial SpasmVertebral Artery DissectionRupture, SpontaneousBrain Hemorrhage, TraumaticTreatment OutcomeDominance, CerebralIntracranial ArteriosclerosisCerebrovascular DisordersMoyamoya DiseaseRenal ArteryFemoral ArteryMesenteric ArteriesCerebral HemorrhageTrigeminal NeuralgiaUltrasonography, DopplerCaloric TestsCarotid Artery DiseasesRegional Blood FlowVertigoCarotid StenosisBrain InfarctionStrokeCerebellopontine AngleRetrospective StudiesIliac ArteryCoronary Artery BypassCollateral CirculationHematomaUltrasonographyRadial ArteryFacial Nerve DiseasesMicrosurgeryFollow-Up StudiesMammary ArteriesFrontal LobeImaging, Three-DimensionalSubclavian ArteryTemporal ArteriesNerve Compression SyndromesTime FactorsElectronystagmographyCarotid Artery, CommonCerebral PalsyVasoconstrictionBrachial ArterySplenic ArteryUmbilical ArteriesCranial Nerve DiseasesCranial Fossa, PosteriorHepatic ArteryCoronary VesselsPostoperative Complications