Neuronal migration disorder presenting with epilepsy: a report of five illustrative cases.

Neuronal migration disorders are an uncommon but well-recognised cause of medically intractable epilepsy. The increasing availability of magnetic resonance imaging of the brain has made it possible to diagnose this condition ante-mortem. There are several types of migration disorders, each with different radiological and clinical features. A case each of focal cortical dysplasia, focal subcortical heterotopia, double cortex syndrome, periventricular nodular heterotopia and closed lip schizencephaly is presented to highlight the distinctive features of each entity.