Fig. 12.

A 53 year old male with chronic hepatic failure presented with acute confusion from acute hepatic/hyperammonemic encephalopathy (AHE). The patient had an elevated serum level of NH₄⁺ 101 ug/dl (normal: <20-40 ug/dl). 12A-D: bilateral symmetric PVWM involvement of the centrum semiovale is present on DWI (A) and FLAIR (B), also with involvement of the thalami (D arrows); involvement of the internal capsules’ posterior limbs (D dotted arrows) is noted on the ADC map (C) and FLAIR (D), being characteristic of AHE.