Spinal Cord Vascular DiseasesInfarctionAnterior Spinal Artery SyndromeBasilar ArteryPonsSpinal CordSpinal FusionVertebral ArteryArteriesScoliosisSpineOrthopedic Fixation DevicesKyphosisThoracic VertebraeAngiographyHypesthesiaSubarachnoid HemorrhageMagnetic Resonance ImagingVertebrobasilar InsufficiencyCerebral ArteriesSpinal DiseasesBone ScrewsLaminectomyInternal FixatorsSpinal Cord DiseasesPulmonary ArteryVertebral Artery DissectionLumbar VertebraeParaplegiaCarotid ArteriesAneurysm, RupturedSpinal Cord InjuriesLongitudinal LigamentsFemoral ArteryRenal ArteryMesenteric ArteriesCervical VertebraeRetrospective StudiesTreatment OutcomeBrain Stem InfarctionsCarotid Artery, InternalIliac ArterySpinal FracturesCoronary Artery BypassPostoperative ComplicationsCerebral AngiographyRadial ArteryMammary ArteriesSubclavian ArteryVasodilation