Malformations of cortical development.

Malformations of Cortical Development (CDM)

Cortical developmental malformations represent a broad group of brain structural abnormalities caused by disruption of the biological processes of cell proliferation, neuronal migration, or cortical organization during embryogenesis.

Classification by Affected Stage

• Proliferation/Differentiation Anomalies: Microcephaly, megalencephaly, focal cortical dysplasia type II.
• Neuronal Migration Anomalies: Lissencephaly (smooth cortex), periventricular or subcortical nodular heterotopias.
• Cortical Organization Anomalies: Polymicrogyria (multiple small gyri) and schizencephaly (transmental clefts).