Review Note

A 72 yr old man has had poorly controlled HTN for 20 years. Over the past day he has had a severe headache with nausea, followed by confusion then convulsions. On exam he is afebrile, but his blood pressure is now 260/150 mm Hg. There is b/l papilledema. What pathologic lesion most likely developed in his brain during the past day? 

Arteriolar fibrinoid necrosis.