Fig. 1

Cortical disorganization in TSC cortical tubers. a Normal control cortex with classic 6-layered lamination. b, c Normally shaped neuronal cells of supra- and infragranular layers. d Deep white matter in a control patient. e Normal appearing cortex in a perilesional sample. f Cortical dyslamination of FCD type IIb in a patient with difficult-to-treat frontal lobe epilepsy. g Dysorganization of the cortex in a cortical tuber of a patient with genetically proven TSC. h, i Dysmorphic neurons (arrows) are present throughout the whole cortex. Scale bar in g equals 500 μm and applies also to a, e, and f. Scale bar in i equals 200 μm and applies also to b–d. j Loss of neurons throughout all cortical layers in TSC cortical tubers and FCD type IIb. k Significant increase in heterotopic neurons in the deep white matter in patients who underwent surgery for FCD Type IIb or cortical tuber resection. l A larger amount of dysmorphic neurons can be detected in FCD type IIb compared to TSC cortical tubers. SG supragranular layers, IG infragranular layers, WM white matter, Co control, PLx perilesional cortex, Tb cortical tuber, IIb FCD type IIb