Hepatic encephalopathy with corticospinal tract involvement demonstrated by diffusion tensor tractography.

A 50-year-old man with liver cirrhosis and esophageal varix for 3 years was diagnosed with hematemesis and treated for a bleeding varix. However, bleeding recurred 11 days later, and he developed drowsiness with left hemiparesis. His left upper and lower extremity muscle strengths based on the manual muscle test at the onset were grade 2/5 and 1/5, respectively. The Babinski sign was positive. His serum ammonia level was elevated to 129.9 µg/dL (normal, 20-80 µg/dL). Magnetic resonance imaging revealed restriction on diffusion and T2-hyperintensities with decreased apparent diffusion coefficient values in the bilateral frontoparietooccipital cortex. The effect was more severe in the right hemisphere and right parietooccipital cortices, which were compatible with hepatic encephalopathy. Although the patient's mental status recovered, significant left-sided weakness and sensory deficit persisted even after 6 months. Diffusion tensor tractography (DTT) performed 3 months post-onset showed decreased volume of the right corticospinal tract. We reported a patient with hepatic encephalopathy involving the corticospinal tract by DTT.