Fetal schizencephaly: pre- and postnatal imaging with a review of the clinical manifestations.

Schizencephaly is a rare malformation of the central nervous system. Prenatal ultrasound (US) allows diagnosis of schizencephaly, although prenatal magnetic resonance (MR) imaging is even more specific in detection of gray matter lining the defect, communication with the ventricle, and other associated structural abnormalities. Six cases of schizencephaly were evaluated at one institution; prenatal US was performed in all cases, and fetal MR imaging was performed in three cases. As with many malformations, more severe cases of schizencephaly often manifest in utero. All of the cases studied were of the open-lip variety; three cases were bilateral, and three were unilateral. The cleft was not appreciated at initial US in only one case, which consisted of a small unilateral defect, with the diagnosis made at subsequent MR imaging. A survey of the clinical literature on schizencephaly shows that the severity of the motor and mental impairments is directly related to the extent of the anatomic defect. The differential diagnosis for a cerebrospinal fluid-containing abnormality of the fetal brain includes both developmental and destructive lesions. Prenatal detection of schizencephaly can assist in management of the pregnancy.