DSA (left vertebral artery injection) shows well-opacified extradural left vertebral artery (arrows) and multiple areas of narrowing of the intracranial vertebral, basilar, and posterior cerebral arteries (arrowheads) (A). High-resolution, contrast-enhanced vessel wall MR image shows wall of the basilar artery uniformly thickened and without enhancement, consistent with vasoconstriction (B and inset).
RCVS: reversible cerebral vasoconstriction syndrome; DSA: digital subtraction angiography; MR: magnetic resonance.