Stroke Duplicated Vertebral Artery Dissection

by Drs. Erez Nossek and Cen Zhang

Anatomy knowledge matters.  Here is an acute completed PCA infarct

Angio — look at transition in vertebral artery caliber. Why?

Selective vert injection

What is this?  Answer is knowledge of anatomy.  There is a variant of proximal “duplicated” vert — where direct aortic origin vert and “classic” subclavian origin vert origins co-exist, usually fusing somewhere in the lower cervical segment into a single vessel.  Below is a different case of this anatomical disposition.  See Vertebral Artery page for much more on this, including key to the arrows

Knowledge of this prompts us to look for another vert origin — and here it is — direct origin off aortic arch — with the associated occlusion. Also note branch to the anterior neck

This is not just anatomical satisfaction — it establishes stroke etiology as artery-to-artery embolism due to dissection.  Mystery solved

Cranial view of PCA occlusion

Retrospective review of CTA shows the same — direct origin vert = solid arrows; subclavian origin vert = dashed arrows; larger caliber vert distal to fusion of the two origin verts = arrowhead;

MIP coronal CTA — image on left shows nicely the dissected segment of the direct origin vert