Focal cortical dysplasia. A T2-FLAIR MRI in the coronal plane in a patient with seizures. Deep in the white matter, adjacent to the lateral ventricles, are multifocal heterotopic aggregates of gray matter, more apparent in the left hemisphere.

Source: Ropper AH, Samuels MA, Klein JP, Prasad S. Adams and Victor's Principles of Neurology, 11e; 2019.