A computed tomographic study of hypertensive encephalopathy

A computerized tomographic scan in a 47-year-old male with hypertensive encephalopathy showed a diffuse, symmetric, well-demarcated, low-density area involving the white matter, the basal ganglia, the midbrain, the pons, and the cerebellum with expansions. Although these structures failed to demonstrate any visible contrast enhancement on the CT-image, the postcontrast attenuation values of these structures were higher than the precontrast values. The cerebral gray matter showed little change between the pre- and postcontrast attenuation values. The abnormalities were completely resolved within one month of the institution of treatment. The total protein and IgG contents in lumbar CSF correlated well with the CT changes: higher contents on the day of an abnormal CT, lower contents on the day of a normal CT. We suggest that the lowdensity areas are vasogenic edema with a collection of edema fluid extravasated through small vessels compromised by the raised arterial pressure. (author)