Imaging Findings in Neonatal and Pediatric Posterior Reversible Encephalopathy Syndrome (PRES) Differ From Adults

Posterior reversible encephalopathy syndrome (PRES) is classically a reversible clinical radiographic syndrome associated with predominantly posterior leukoencephalopathy on neuroimaging. Magnetic resonance imaging (MRI) in adults demonstrates almost universally reversible parietal-occipital disease. We aimed to demonstrate in a cohort of children that "atypical" distribution is expected, acutely and on follow-up.A retrospective review of children diagnosed with PRES from 2010 to 2018 at our children's hospital was performed. All had MRI at diagnoses, with over half having follow-up MRIs. Images were reviewed by a neuroradiology-trained pediatric radiologist for confirmation of findings consistent with PRES/identification of involved regions.Nineteen patients (aged zero to 18 years, 53% female) were included. Notably, two were infants. Nearly all had seizures; all had altered mental status and hypertension. Fifteen (84%) had MRI described as "atypical." Distribution of MRI findings was anatomically widespread, including nine with frontal findings. Twelve (63%) had follow-up imaging, of which approximately half remained abnormal.Pediatric PRES MRI findings were more often atypical at time of diagnosis. Vasogenic edema related to the acute phases of PRES typically resolved; however, follow-up imaging identified new volume loss in the areas affected. Two of our subjects were younger than 13 months, younger than typically described. Our series demonstrates that imaging distribution in children with PRES does not mirror the classical posterior, reversible distribution described in adults and continues the recent trend of identifying PRES in infants.