Ante-and postnatal evaluation of the Dandy-Walker syndrome.

In three cases an antenatal diagnosis of isolated Dandy-Walker cyst was made at 22-28 weeks of gestation by ultrasound examination. Biparietal growth and the relative severity of the anomaly remained constant, so that all cases could be safely delivered at term. Postnatally, the diagnosis was confirmed during the first days of life by ultrasound and computed tomography (CT). Early neonatal shunting procedures were performed. Dual shunts were inserted in all three cases, and mental and physical development were observed to be normal during a follow-up of from 1.5 to 4.5 years. Early antenatal diagnosis of Dandy-Walker cyst may improve the prognosis and reduce the mortality, which has been reported to be 30%-48%. Dual shunting of both the cyst in the posterior fossa and the lateral ventricles has proved to be a safe and reliable method during the neonatal period.