Girl aged 11 years and 10 months. Normal female karyotype, normal gestation and delivery. Brain magnetic resonance imaging (MRI) shows agenesis of the corpus callosum together with extensive neuronal migration abnormalities. This patient presents with epilepsy in infancy with the first seizure episodes at 2 years of age. Electroencephalographic (EEG) recordings demonstrate an asymmetrical hypsarrhythmia. Funduscopic examination shows a complete papilla in the right eye, peripapillary pigment and areas of peripapillary hypopigmented chorioretinal lacunae extending into the retinal vascular arcades. However, there is no macular involvement. The left fundus shows a colobomatous optic disc and small chorioretinal hypopigmented areas. There are no other renal or vertebral malformations. The patient is characterised by a long survival, with a current age of 11 years and 10 months, but presenting a very severe psychomotor retardation.