fig 4.

Case 11: 48-year-old man being treated with CSA who presented with generalized seizures shortly before imaging.

A and B, Proton density–weighted (A) and axial T2-weighted (B) sections reveal a nonspecific punctate white matter hyperintensity (arrow) in the left parietal lobe.

C, Corresponding turbo-FLAIR image shows biparietal increased signal within the cortex (white arrows) and subcortical white matter (black arrow), representing edema and suggesting the radiologic diagnosis of PRES.

D and E, Adjacent proton density–weighted (D) and T2-weighted (E) images, one level superiorly, show increased cortical (white arrows) and subcortical white matter signal due to edema.

F, Turbo-FLAIR image at same level again reveals the cortical-based hyperintensities that are difficult to appreciate on standard dual-echo sequences, owing to the adjacent bright CSF. FLAIR unmasks this abnormality by suppressing CSF signal. This case was assigned a moderate severity score on the basis of the FLAIR imaging findings, although on the basis of proton density–or T2-weighted images it would have been considered mild.