This is the MRI brain and neck angiogram of a brain dead patient. Notice there is the good blood flow everywhere except the brain.
It started with a large cerebellar infarct, possibly due to a hypoxic event, which led to extensive swelling of the cerebellum causing effacement of the basal cisterns and the 4th ventricule, and hydrocephalus as seen later in the video. All these lead to increased resistant in the arteries and eventually blood supply to the brain stops.
Comparison with a normal brain is shows. Notice how spacious the ventricles, cisterns and sulci are.
Link to youtube: https://youtu.be/_OS7mbbh1RI
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