Bones, orbits, visualized paranasal sinuses, mastoid air cells:
Suboptimally evaluated on limited to stroke sequences, no gross
Additional comment: Near absent ASL signal to the cerebral hemispheres, with slight sparing of the right hemisphere.
Given extremely limited intracranial flow on initial MR angiography, series 5, MR imaging was repeated and showed better flow related enhancement, however confirmed majority of this severely diminished flow related enhancement to not be artifactual. There is substantial slab artifact, flow related enhancement is seen within the distal cervical segments of both internal carotid arteries however this tapers to absent enhancement in the petrous and cavernous segments. There is reconstitution of flow related enhancement in the right supraclinoid internal carotid artery, which may be due to retrograde flow across patent right posterior to indicating artery, small amount of flow related enhancement is seen in right M2 and M3 branches. Small amount of flow related enhancement is also seen in the bilateral V4 segments, and left PICA. No supratentorial left-sided arterial flow related enhancement is seen intracranially.
1. Large cortical and subcortical infarct involving the entire left cerebral hemisphere, and extensive cortical infarct of the right cerebral hemisphere, as well as bilateral superior cerebellar
territory cortical infarcts and punctate pontine infarct. Minimal intracranial arterial flow related enhancement, some sparing of the posterior circulation and right anterior circulation, and absent
arterial flow related enhancement to the left cerebral hemisphere. Given large volume of infarct, and limited intracranial arterial flow, findings may be explained by prior chronic carotid or vertebral occlusions with new acute arterial occlusion to vessel which was
previously sole supply to the brain. Alternatively, findings could be due to severe hypoperfusion state.