Cerebral ventricular size in children: a two-dimensional ultrasonic study.

The width of the bodies of both lateral ventricles was studied in 833 children using B-mode echography. It could be accurately measured in 99.9% of those under the age of 2, 94% of these 2 to 5, and 65% of those 6 to 12. The normal lateral ventricular ratio or LVR (width of body of LV/0.5 X internal skull diameter) was 0.24-0.36, but there was a borderline area and the upper part of this range (0.34-0.36) included some cases of early hydrocephalus. In 72% of the children with a head circumference greater than the 98th percentile, the LVR was 0.24-0.36. The greatest transverse diameter of the atrium of the normal lateral ventricle in children appears to be 10 mm, that of the normal third ventricle 5 mm. A water-delay system is described as being superior to a contact system for B-mode echoencephalography.