A 2 year-old girl presented with seizures and developmental delay.

Schizencephaly is a rare disorder of neuronal migration. Similar to porencephaly, there is a cerebrospinal fluid–filled cleft, but in contrast to porencephaly, the cleft is lined by gray matter. The cleft typically extends from the ventricle to the surface of the brain. Schizencephaly is commonly divided into types I and II. In type I, the clefts are fused (so called fused lips), whereas in type II, the clefts are open (so-called open lips). In this case, there is one large open cleft, and would be considered type II schizencephaly. Similar to porencephaly, patients present in infancy with seizures, developmental delay or focal neurological deficits.