B-mode echoencephalography in the normal and high risk infant.

Commercially available high resolution, contact, gray scale imaging systems can now dependably visualize the normal and abnormal ventricular system as well as some other intracranial structures in all newborns. On 25 normal infants and 41 high risk infants, 135 B-mode echoencephalograms were performed. The technique for obtaining these scans is described. The normal lateral ventricle at the midbody in term infants is 0.9--1.3 cm wide (mean, 1.1 cm). Normal ratio of lateral ventricle to hemisphere is 28% (range, 24%--30%). High risk premature infants have a ratio of 31% (range, 24%--34%). The demonstration of hydrocephalus and cystic intracranial masses is reliable and the correlation with computed tomography is excellent. Postoperative or high risk infants can be repeatedly evaluated without radiation, at a lower cost, and more rapidly with ultrasound than with computed tomography. Ventricular size can be closely monitored and shunt failure detected at any early stage.