typical imaging findings in posterior reversible encephalopathy syndrome (pres)
TRANSCRIPT
Letter to the Editor
Typical Imaging Findings in Posterior Reversible EncephalopathySyndrome (PRES)
Christian Roth, MD, Andreas Ferbert, MD, PhDFrom the Department of Neurology, Klinikum Kassel, Germany (CR, AF).
Keywords: RPLS, MRI, encephalopa-thy, PRES.
Acceptance: Received August 5, 2010.Accepted for publication September 19,2010.
Correspondence: Address corre-spondence to Christian Roth, MD,Department of Neurology, Klinikum Kas-sel, Moenchebergstraße 41-43, D-34125Kassel, Germany, E-mail: [email protected].
J Neuroimaging 2010;XX:1-2.DOI: 10.1111/j.1552-6569.2010.00540.x
Posterior Reversible Encephalopathy Syndrome (PRES) hasattracted increased interest in recent years. There are manypublications on the topic, especially case reports and papersdiscussing radiological chances. Recently, a Chinese group pub-lished a retrospective series of 24 patients with PRES.1 Clinicalstudies with more than only a few cases are rare. Therefore,it is interesting to read a study focused on the clinical andneuroradiological features of PRES.1 It seems obvious; there-fore, that PRES occurs not only just in the Western world, butworldwide.
The authors found an atypical involvement of the frontallobe in 54.2% and of the basal ganglia gray matter in 12.5%.Lesion of the parietal and occipital lobe occurred in 87.5%and 83.3%. The authors, consequently, have concluded thata large proportion of PRES-patients probably show atypicalimaging abnormalities. These findings are comparable to otherpublications2 and to our own studies.3,4 We found an involve-ment of the basal ganglia, brainstem, or cerebellum in aboutone-third of cases studied. But, such an occurrence never ap-peared isolated (Fig 1). The main MRI lesions are located par-ticularly in the parieto-occipital regions (90-95%).2,3 All ourpatients showed a bilateral affection, frequently asymmetri-cally. This suggests that PRES shows a typical MRI patternon fluid-attenuated inversion recovery (FLAIR)-weighted imag-ing in PRES patients that makes the following diagnoses morelikely:
– The predominant affected region is parieto-occipital.– Both hemispheres are affected, sometimes asymmetrically– The subcortical white matter is always affected, but an involve-
ment of cortex is also very common
– Isolated atypical lesions, for example, of the basal ganglia orcerebellum are rare, and one should probably reconsider thediagnosis.
References1. Ni J, Zhou LX, Hao HL, et al. The Clinical and radiological spectrum
of posterior reversible encephalopathy syndrome: a retrospectiveseries of 24 patients. J Neuroimaging 2010;20:20-28.
2. McKinney AM, Short J, Truwit CL, et al. Posterior reversible en-cephalopathy syndrome: incidence of atypical regions of involve-ment and imaging findings. AJR Am J Roentgenol 2007;189:904-912.
3. Roth C, Ferbert A. Posterior reversible encephalopathy syndrome:long-term follow-up. J Neurol Neurosurg Psychiatry 2010;81:773-777.
4. Roth C, Ferbert A. Posterior reversible encephalopathy syndrome:is there a difference between pregnant and non-pregnant patients?Eur Neurol 2009;62:142-148.
Copyright ◦C 2010 by the American Society of Neuroimaging 1
Fig 1. Thirty-four-year-old patient with PRES and pheochromocytoma. MRI (FLAIR) shows atypical involvement of the basal ganglia graymatter and of the cerebellum. Furthermore, there are typical patterns with subcortical parieotooccipital lesions. DWI (not shown here) iscompletely normal.
2 Journal of Neuroimaging Vol XX No XX 2010