The many faces of PRES





Not always posterior, not always reversible, not always associated with encephalopathy. To give you the actual numbers, 75% of cases have frontal and temporal involvement, and a third affect the brainstem. 20% of patients have lasting deficits, whether focal, cognitive, or epileptic in nature. And encephalopathy, a hallmark of the disorder, occurs in about half of cases. So there you have it. For more details, check out the latest podcast on BrainWaves where we discuss these and other atypical features of PRES:

Because this episode talks about all the interesting features of PRES, we will be using this blog to show them to you.


PRES with sulcal subarachnoid hemorrhage in a 67-year-old woman with ARDS, ventilator-dependent respiratory failure, and multifocal pneumonia with persistent obtundation. Axial CT scan (left) with subarachnoid hemorrhage and axial T2 (right) with posterior-predominant hyperintense signal concerning for PRES.



PRES mimicking a right PCA infarction in a 45-year-old woman s/p renal transplant on tacrolimus with seizure and a left homonymous hemianopsia. Axial FLAIR sequence (left) and DWI (right) demonstrating restricted diffusion with surrounding vasogenic edema. Repeat imaging 3 months later was normal.


Patient with PRES associated with bevacizumab use. Slide courtesy of Amy Pruitt.


PRES associated with calcineurin inhibitor use. Slide courtesy of Amy Pruitt.


PRES mimicking laminar necrosis. Slide courtesy of Amy Pruitt.


PRES with associated fourth ventricular compromise and obstructive hydrocephalus.


PRES mimicking osmotic demyelination. Slide courtesy of Amy Pruitt.


PRES mimicking multiple sclerosis lesions in a patient with tacrolimus toxicity. Slide courtesy of Amy Pruitt.



Axial T2-weighted thoracic spine MRI (left) and axial FLAIR MRI of the brain (right) in a young man with decompression sickness and PRES of the brain and spinal cord.


[Jim Siegler]

The content in this episode was vetted and approved by Amy Pruitt. Several images are also courtesy of Amy Pruitt.


Hinchey J, Chaves C, Appignani B, Breen J, Pao L, Wang A, Pessin MS, Lamy C, Mas JL and Caplan LR. A reversible posterior leukoencephalopathy syndrome. The New England journal of medicine. 1996;334:494-500.

Casey SO, Sampaio RC, Michel E and Truwit CL. Posterior reversible encephalopathy syndrome: utility of fluid-attenuated inversion recovery MR imaging in the detection of cortical and subcortical lesions. AJNR American journal of neuroradiology. 2000;21:1199-206.

Fugate JE and Rabinstein AA. Posterior reversible encephalopathy syndrome: clinical and radiological manifestations, pathophysiology, and outstanding questions. The Lancet Neurology. 2015;14:914-25.

Bartynski WS. Posterior reversible encephalopathy syndrome, part 2: controversies surrounding pathophysiology of vasogenic edema. AJNR American journal of neuroradiology. 2008;29:1043-9.

Bartynski WS. Posterior reversible encephalopathy syndrome, part 1: fundamental imaging and clinical features. AJNR American journal of neuroradiology. 2008;29:1036-42.

Hefzy HM, Bartynski WS, Boardman JF and Lacomis D. Hemorrhage in posterior reversible encephalopathy syndrome: imaging and clinical features. AJNR American journal of neuroradiology. 2009;30:1371-9.

You may also like...

Leave a Reply

Your email address will not be published. Required fields are marked *