MRI Findings in Childhood PRES: What is Different than the Adults?

Posterior reversible encephalopathy syndrome (PRES) is a clinical scenario with convulsion, vision abnormalities, altered mental status, and headaches in the presence of an underlying etiology, and the diagnosis can be made by support of radiological studies. In this study, we evaluated the magnetic resonance imaging (MRI) findings of PRES in children and compared our findings with that of the known features in adults, and reviewed the possible pathophysiological reasons that may cause the difference.

A total of 29 children (13 male, 16 female, aged 1-17 years, mean age: 10 years) diagnosed as having PRES were retrospectively reviewed. Clinical records were analyzed for the clinical symptoms and the underlying etiology. MR images were evaluated for the distribution of lesions, contrast enhancement, diffusion restriction, and hemorrhage.

Presenting symptoms and underlying etiologies were variable. Frontal lobe (66 %) edema was almost as common as parietal and occipital involvement. Cerebellar involvement was present in almost half of the patients (48 %), which was more frequent than in the adult patients. Contrast enhancement is another finding that was found to be more common in children than in the adults (39 %). Four patients had diffusion restriction (15 %) and four patients had hemorrhage (%15), which are almost the same frequency as in the adults.

The increased incidence of cerebellar involvement may show that the posterior circulation in children is more vulnerable than the adults. The contrast enhancement in children, which is seen more commonly than in the adults, may show that the pathophysiology in children may be more commonly related to blood-brain barrier breakdown, which can support the theory of the toxic endothelial injury.