[Reversible posterior encephalopathy syndrome: case report].

The posterior reversible leukoencephalopathy syndrome (PRES) is a recently proposed cliniconeuroradiologic entity. The most common causes of PRES are hypertensive encephalopathy, eclampsia, cyclosporin A neurotoxicity and the uremic encephalopathies. Most patients are markedly hypertensive at presentation, although some have only mildly elevated or even normal blood pressure. Symptoms may include headache, nausea, vomiting, altered mental status, seizures,stupor, and visual disturbances. On CT and MR studies, edema has been reported in a relatively symmetrical pattern, typically in the subcortical white matter and occasionally in the cortex of the occipital and parietal lobes. These often striking imaging findings usually are resolved on follow-up studies obtained after appropriate therapy. Diffusion-weighted images would not show hyperintense signal because of the presence of interstitial rather than cytotoxic edema. We report a case of PRES due to hypertensive encephalopathy studied by CT and MRI.