[Malformations of cortical development: what's new?]

Malformations of cortical development (MCDs) are structural abnormalities that disrupt the normal process of cortical development in utero. MCDs include microcephaly with simplified gyral pattern/microlyssencephaly, hemimegalencephaly, focal cortical dysplasia, lissencephaly, heterotopia, polymicrogyria, and schizencephaly. The debut of MCD can be with pharmacoresistant epilepsy, developmental delay, neurologic deficits, or cognitive impairment. The diagnostic pathway for MCDs is complex owing to wide variations in presentation and etiology. Although the definitive diagnosis of MCD depends on histopathology, neuroimages have an important role in this process. Furthermore, knowing the disturbance of the molecular pathway involved is important. Increased understanding of the molecular biology and recent advances in genetic testing have caused rapid growth in the knowledge of the genetic causes of MCDs, allowing for information on prognosis, recurrence risk, and prediction of treatment outcomes.