Case 13 Answer: global hypoxia

Above is the a comparison with the same patient 4 days prior. As everyone saw, there is sulcal effacement and complete lack of gray-white differentiation, but notice the hypodensities in the caudate heads as well. I believe this was the result of a post-operative cardiac arrest with resultant global hypoxic-ischemic injury (or encephalopathy… it has a bunch of similar names).

short reference: http://radiopaedia.org/articles/hypoxic-ischemic-brain-damage

more than you ever wanted to know: http://radiographics.rsna.org/content/28/2/417.full