Case 23 Answer

Perhaps I missed the mark on this one. The goal was to notice the the swollen hypodense gyral pattern in the posterior left frontal lobe/parietal lobe. On top of that are some serpentine hyperdensities that conform to the gyri.

Answer: cortical laminar necrosis.

It is variable on when and how it shows up/progresses, but the key to remember is that it is not hemorrhage and should not be mistaken for hemorrhagic conversion (Often these are seen on f/u exams, which is the point of the history here). 

Here is a good series progression: https://radiopaedia.org/cases/evolution-of-cerebral-infarction-oedema-to-laminar-necrosis-and-haemorrhagic-transformation-then-to-atrophy

better write up than me: https://radiopaedia.org/articles/cortical-laminar-necrosis