Nearly symmetrical large areas of diffusion restriction is seen involving bilateral parietooccipital, frontal lobes, corpus callosum, external capsules, posterior limbs of both internal capsules, bilateral thalami and lateral aspects of cerebral peduncles.
The splenium of the corpus callosum is affected, producing the so-called boomerang sign.
Prominence of bilateral internal cerebral and deep medullary veins is seen on GRE images, likely due to venous congestion.