Basilar ArteryIntracranial AneurysmAneurysmAneurysm, InfectedArteriesVertebrobasilar InsufficiencyAortic AneurysmCerebral AngiographyAortic Aneurysm, ThoracicHeart AneurysmSubarachnoid HemorrhageVertebral ArteryAneurysm, DissectingCerebral ArteriesEmbolization, TherapeuticIliac AneurysmTomography, X-Ray ComputedCoronary AneurysmPulmonary ArteryCarotid ArteriesBlood Vessel Prosthesis ImplantationRenal ArteryAngiography, Digital SubtractionAneurysm, FalseBrain Stem InfarctionsCarotid Artery, InternalFemoral ArteryVasospasm, IntracranialAortic RuptureIliac ArteryTreatment OutcomeBlood Vessel ProsthesisMesenteric ArteriesEndovascular ProceduresAorta, AbdominalCarotid Artery DiseasesStentsVasodilationAortographyAngiographyVascular Surgical ProceduresSplenic ArteryVasoconstrictionSubclavian ArteryMuscle, Smooth, VascularArterial Occlusive DiseasesCoronary Artery BypassCircle of WillisCeliac ArteryCerebrovascular CirculationRadial ArteryDogsMiddle Cerebral ArteryMesenteric Artery, SuperiorMammary ArteriesFollow-Up StudiesSurgical InstrumentsCarotid Artery, CommonVasodilator AgentsRetrospective StudiesMagnetic Resonance AngiographyPosterior Cerebral ArteryHepatic ArteryTime FactorsSerotoninPostoperative ComplicationsDilatation, PathologicAnterior Cerebral ArteryBrachial ArteryOphthalmic ArteryPopliteal ArteryCoronary VesselsRabbitsPapaverinePotassium ChlorideIntracranial Embolism and ThrombosisVasoconstrictor AgentsMuscle ContractionIntracranial ThrombosisTemporal ArteriesPicolinesIschemic Attack, TransientEndothelium, VascularProsthesis DesignMechanical ThrombolysisUltrasonography, Doppler, TranscranialSumatriptanIntracranial ArteriosclerosisNeurosurgical ProceduresVertebral Artery DissectionAcetylcholineRenal Artery ObstructionThoracic ArteriesBronchial ArteriesAneurysm, RupturedAngioplastyUlnar ArteryCerebral InfarctionRetreatmentVascular Patency