Fig. 2.

Brain imaging findings. a–c Axial T2-weighted images at different levels (a, b) and sagittal volumetric acquisition T1-weighted 3D-MPR thin slice image (c) of a normal 25-year-old individual. Note normal dense gyral pattern and normal cortical thickness (around 3 mm) in comparison with the following images. d–f Axial T2-weighted image (d), sagittal volumetric acquisition T1-weighted 3D-IR thin slice image (e), and coronal T1 FLAIR (fluid attenuated inversion recovery) image (f) in patient VIII/9, FIN-14 at the age of 2 years 8 months demonstrates symmetric pachygyria (broad and shallow sulci) with mild cortical thickening up to 8 mm. The frontotemporal predilection of both pachygyria and cortical thickening is nicely depicted in figure e, whereas the occipitoparietal regions show much milder changes. g–i Axial T2-weighted images at different levels (g, h) and coronal T1-FLAIR image (i) in patient III/4, FIN-9 at the age 9 years 6 months show similar findings as in figures d–f. A small temporal arachnoid cyst is marked by an asterisk and prominent perivascular space by an arrow. j–l Axial (j) and coronal (k) T2-weighted images in patient IX/4, FIN-5 at the age of 43 years demonstrate a bit less pronounced although evident pachygyria and mild cortical thickening of 6–7 mm. Prominent perivascular spaces (arrow) are also evident on both sides (k). T1-weighted sagittal image shows normal midline structures (l). m–o Good-quality thin-slice computer tomography (CT) scan shows pachygyria and mild cortical thickening almost as good as MRI in an elderly male (IX/10, FIN-6). Multiplanar reconstruction (MPR) CT-images in axial (m, n) and coronal (o) planes