Vertebral Artery Ostial Stenosis: Prevalence by Digital Subtraction Angiography, MR Angiography, and CT Angiography

Abstract

The prevalence of VOS as determined by DSA is low and increases with patient age and correlates with factors such as anterior infarct (18.4%), posterior infarct (33.3%), carotid atherosclerosis (30.8%), and vertebrobasilar insufficiency (33%). Patients being evaluated for reasons less closely correlated with atherosclerotic disease, such as arteriovenous malformation (AVM) or hemorrhage showed a lower prevalence of VA stenosis (brain aneurysm or AVM 5/121, 4.1%, brain hemorrhage 5/153, 3.3%). Routine clinical MRA significantly overestimates VOS prevalence, and findings suggest that CTA underestimates the degree and prevalence of VOS.