Hyperdense vessel sign (right vertebral artery)

Wedge-shaped hypoattenuation in the inferior aspect of the right cerebellar hemisphere with loss of grey-white matter differentiation, consistent with a PICA territory infarct. Dense vessel sign in the right vertebral artery at the foramen magnum. No tonsillar herniation or fourth ventricular effacement.

Occlusion throughout the partially imaged cervical and intracranial portions of the right vertebral artery with a small amount filling distally. No right PICA opacification.

The imaged left vertebral artery and basilar arteries are patent. The circle of Willis and major branches are otherwise patent. Incidental ACA trifurcation (normal variant).

Confirmed acute right cerebellar hemisphere infarct in the PICA territory. Additional acute infarct focus in the left corona radiata.