60 year old with bilateral lung transplants presents with new seizures

FLAIR

DWI

T1 post Gad

Findings:

Edema-like high T2, negative DWI, foci with patchy enhancement predominately within white matter but also with deep grey and posterior grey matter involvement

DDX:

Encephalitis, Sarcoid, Lymphoma, atypical ischemic injury, PRES

Diagnosis:

PRES (Posterior Reversible Encephalopathy Syndrome) secondary to tacrolymus (drug to reduce transplant rejection)

Discussion:

Although classically occipital/parietal, PRES can often involve the anterior cortex as well as the deep grey nuclei and posterior fossa. It can often be distinguished from infarct by the lack of restricted diffusion althought in advanced cases hemorrhage and restricted diffusion can be seen.

Submitted by Farrah Jabeen, MD, UW Neuroradiology Fellow