FIG 1. Normal variations, which can complicate assessment of pathologic cortical hyperintensity on FLAIR and DWI.

A, Axial FLAIR (TR/TE/TI = 10000/140/2200) image shows insular cortex slightly hyperintense (arrows) to neocortex.

B, More superior axial FLAIR image shows relative hyperintensity in cingulate cortex (arrows).

C, Axial DWI (TR/TE = 8000/minimal, b = 1000 s/mm², same level as A) shows hyperintensity in bilateral insular cortex (arrows).

D, More superior DWI (same level as B) shows relative hyperintensity cingulate cortex (arrows), accentuated by frontal magnetic susceptibility artifact.