Male, 63 years old, with lethargy, weakness, failure to thrive. CT with possible evidence of PRES. No evidence of restricted diffusion is seen. However, there is extensive confluent periventricular T2 hyperintensity, particularly in the periatrial regions, with patchy hyperintensity in the subcortical white matter and in the pons. No edema or mass effect is detected. There are no findings to suggest acute intracranial hemorrhage or any abnormal extra axial fluid collections. The ventricles and sulci are slightly prominent compatible with underlying volume loss.
Fairly extensive periventricular and subcortical hyperintensity is seen without evidence of restricted diffusion, edema or mass effect. The pattern of these lesions is not particularly suggestive of PRES or any other specific underlying etiology. Statistically, chronic small vessel ischemic disease would be most likely.