Abnormalities of the neonatal cerebral ventricles.

High-resolution ultrasonography allows accurate assessment of ventricular size and contour in the infant, so that conditions such as hydrocephalus, holoprosencephaly, and agenesis of the corpus callosum can be diagnosed. Ventricular shunt catheter placement can be guided, and some of the complications of cerebrospinal fluid shunt systems can be identified. Infection of the ventricular fluid causes striking findings, including increased echogenicity and septation within the lumen.