Focal cortical dysplasia type IIb

Description

Cortical lamination is frequently disrupted with the exception of Layer 1. The myelin content may also be altered in underlying subcortical white matter. Other cortical layer abnormalities are frequently encountered and should not be separately classified, including abnormal isocortical layer organization adjacent to the main lesion, as well as heterotopic neurons in Layer 1 or white matter. Histopathologically similar lesions are observed in cortical tubers and other gross MCDs, i.e. hemimegalencephaly or schizencephaly.; A subtype of focal cortical dysplasia type II that is characterized by dysmorphic neurons (significantly enlarged with accumulation of neurofilament proteins) and balloon cells.