Imaging of posterior reversible encephalopathy syndrome

Introduction. Posterior reversible encephalopathy syndrome (PRES) is a rare recently-described clinical-radiological entity characterized by the combination of neurological symptoms and usually reversible neuro-images of bilateral posterior cerebral edema. The differential diagnosis with cerebral infarction can be a challenge. Methods. A retrospective study was conducted from January 2006 to September 2010 including all cases of PRES observed in intensive care unit patients with varying predisposing conditions. Imaging findings, cerebral location and difficulty encountered with differential diagnosis were examined. Results. The study cohort included four women and one man, mean age 30 years (range 23-44) with various predisposing conditions: cesarean section with spinal anesthesia in a context of prematurity (n = 2); cesarean section for intrauterine fetal death (n = 1); lupus nephritis (n = 1); (hypertension (n = 1). The brain computed tomography scan was unremarkable for the first two patients and showed lesions in favor of subsequent infarction in the others. Magnetic resonance imaging (MRI) was the key diagnostic element for PRES showing signal abnormalities on T2, FLAIR and diffusion sequences, with a typical parieto-occipital localization. Conclusion/Discussion. PRES is a little-known disease. Prognosis is good with early diagnosis and proper management; imaging with MRI is the key to diagnosis. (c) 2013 Elsevier Masson SAS. All rights reserved.