Pediatric and Adolescent Medicine

Cortical development malformations (CDM) and specifically disorders of neuronal migration are a group of congenital malformations of the central nervous system (CNS) that are linked to some of the neurodevelopment disorders frequently described in children, such as mental retardation, autism, schizophrenia and epilepsy, among others. CDM are classified into three groups: Group I for alterations in proliferation and/or glial and neuronal apoptosis; Group II for neuronal migration disorders; and group III for secondary malformations due to postmigrational alterations of development. Neocortical neurons migration occurs preferentially from the fifth week of gestation until the twenty-second gestational week. Neuronal migration disorders are classified into four groups: II. A lissencephaly, II. B periventricular heterotopia, II. C subcortical heterotopia and II. D sublobar dysplasia and "cobblestone" malformations.