Fig 4.

Negative MR imaging findings with minor sulcal abnormalities. Coronal T2WI (A), FLAIR (B), and T1WI (C) in a 36-year-old man with right nocturnal frontal lobe epilepsy, onset at 20 years of age. None of the 6 criteria were found. A minor sulcal abnormality is perceptible in the right superior frontal area, with an unusually large and deep sulcus (arrow). D and E, Cortical specimen. Deep part of the pathologic sulcus with typical type 2a FCD features: cortical disorganization and the presence of giant neurons (arrowhead) without balloon cells. Note that the good delineation of the gray-white matter interface (double arrow) is correlated with the absence of blurring on MR imaging (Klüver-Barrera, original magnification ×5 [D]; ×15 [E]).