Basilar ArterySubarachnoid HemorrhageVasospasm, IntracranialSubarachnoid SpaceIntracranial AneurysmArteriesVertebrobasilar InsufficiencyCerebral ArteriesCerebral AngiographyAneurysm, RupturedCerebral HemorrhageVertebral ArteryHemorrhageTomography, X-Ray ComputedBrain Stem InfarctionsCarotid ArteriesPulmonary ArteryCerebrovascular CirculationIschemic Attack, TransientVasoconstrictionCisterna MagnaIntracranial HemorrhagesAngiography, Digital SubtractionRupture, SpontaneousCarotid Artery, InternalEmbolization, TherapeuticMesenteric ArteriesHydrocephalusVasodilationRenal ArterySubarachnoid Hemorrhage, TraumaticFemoral ArteryBrain IschemiaTreatment OutcomeNimodipineSpinal PunctureCerebral InfarctionMiddle Cerebral ArteryGlasgow Outcome ScaleMuscle, Smooth, VascularDogsMagnetic Resonance AngiographyUltrasonography, Doppler, TranscranialVasodilator AgentsPapaverineTime FactorsCarotid Artery DiseasesIliac ArteryArterial Occlusive DiseasesCerebrovascular DisordersIntracranial PressureSerotoninVertebral Artery DissectionCircle of WillisCoronary Artery BypassProspective StudiesAngiographyGlasgow Coma ScaleSurgical InstrumentsPosterior Cerebral ArteryBrainRadial ArteryRabbitsMammary ArteriesNeurosurgical ProceduresMagnetic Resonance ImagingRetinal HemorrhageRetrospective StudiesVentriculostomyComaDisease Models, AnimalSubclavian ArteryAneurysmPotassium ChlorideVasoconstrictor AgentsStrokeFollow-Up StudiesIntracranial Embolism and ThrombosisPonsHematoma, SubduralVitreous HemorrhageHeadacheSplenic ArteryMuscle ContractionIntracranial ThrombosisBrachial ArteryEndothelium, VascularCraniotomyCoronary VesselsFatal OutcomeHepatic ArteryRisk FactorsIntracranial ArteriosclerosisRats, Sprague-DawleyIntracranial Arteriovenous MalformationsInjections, Intra-ArterialCarotid Artery, CommonInfusions, Intra-ArterialPostpartum HemorrhageAcute Disease