Neuro_MR_Brain: 52 M, ESRD, LOC during dialysis

CLINICAL HISTORY: 52-year-old man with stage renal disease, acute stroke transfer, loss of consciousness during dialysis.
Parenchyma, ventricles, and extra-axial spaces: There is extensive restricted diffusion throughout the entire left cerebral hemisphere involving the cortex and white matter, with relative sparing of the deep gray nuclei. Additionally there is cortical restricted diffusion in the right cerebral hemisphere, as well as restricted diffusion in the bilateral hippocampisuperior cerebellar hemispheres right greater than left, and in the pons. Findings most compatible with acute infarction. No mass effect. Area of low GRE signal over the left temporal convexity which may represent vessel, calcification, or hemorrhage. Punctate focus of low GRE signal in the region of the left sylvian fissure, may be vascular or represent punctate hemorrhage.
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.

(Global cerebral infarction, absent intracranial flow)

Accession: CL27388337

Study description: MR BRAIN