Cerebral AngiographyAngiographyMagnetic Resonance AngiographyAngiography, Digital SubtractionCoronary AngiographyCerebral ArteriesIntracranial AneurysmCerebral InfarctionSubarachnoid HemorrhageIntracranial Arteriovenous MalformationsTomography, X-Ray ComputedCerebrovascular CirculationCerebral VeinsCranial SinusesVertebral ArteryMoyamoya DiseaseCarotid Artery, InternalCerebral HemorrhagePosterior Cerebral ArteryIschemic Attack, TransientCircle of WillisCentral Nervous System Vascular MalformationsCerebrovascular DisordersMiddle Cerebral ArteryAneurysm, RupturedBrain IschemiaFluorescein AngiographyMagnetic Resonance ImagingIntracranial Embolism and ThrombosisCerebral RevascularizationVasospasm, IntracranialBasilar ArteryEmbolization, TherapeuticArterial Occlusive DiseasesCerebral Arterial DiseasesAnterior Cerebral ArteryCerebral PalsyVasculitis, Central Nervous SystemCarotid Artery DiseasesBrainContrast MediaCarotid StenosisVertebrobasilar InsufficiencySinus Thrombosis, IntracranialIntracranial ArteriosclerosisBlindness, CorticalCraniotomyArteriovenous FistulaEpilepsy, Tonic-ClonicEndarterectomyCollateral CirculationArteriovenous MalformationsBlood Flow VelocityCarotid ArteriesIntracranial EmbolismNeurologic ExaminationNeurosurgical ProceduresHematoma, SubduralCranial Fossa, AnteriorInfarction, Middle Cerebral ArterySensitivity and SpecificityConstriction, PathologicProspective StudiesCarotid-Cavernous Sinus FistulaCavernous SinusTreatment OutcomeVertebral Artery DissectionMalaria, CerebralSurgical InstrumentsTemporal ArteriesHematoma, Subdural, IntracranialComaLateral Medullary SyndromeHeadacheFollow-Up StudiesRetrospective StudiesRadionuclide AngiographyIntracranial HemorrhagesAneurysm, InfectedTime FactorsHematomaRemission, SpontaneousCatheterizationRupture, SpontaneousUltrasonography, Doppler, TranscranialCarotid Artery ThrombosisDura MaterRadial ArteryImaging, Three-DimensionalUltrasonographyStrokeCoronary Artery DiseasePneumonia, AspirationEndarterectomy, CarotidAneurysm, DissectingCoronary StenosisRisk FactorsTomography, Spiral ComputedRecurrencePredictive Value of Tests