Figure 3-4.

MRI curvilinear reconstruction (A, C, and E) in a patient with frontal lobe seizures and previous MRIs considered as normal. Panel D shows an axial T1-weighted image at the level of the abnormality. Note the area with abnormal gyri (H, I, red arrows), a deep sulcus, and a depression on the overlying surface of the brain (G-I, blue arrows) with increased CSF space that is better observed in the curvilinear reconstructions in the right frontal lobe (A-C, E, F). These abnormalities and the focal cortical-subcortical blurring become obvious in the curvilinear reconstructions in layers going from 4 mm (A) to 12 mm (F) below the surface of the brain. The T2-weighted and fluid-attenuated inversion recovery (FLAIR) images (not shown) did not show abnormal signal. The patient, a 36-year-old woman, underwent a right frontal resection under electrocorticography and has been seizure free for 4 years. Histopathology showed focal cortical dysplasia type IIA.