The evolution of neonatal herpes encephalitis as demonstrated by cranial ultrasound with CT correlation.

Three neonates with herpes encephalitis had serial cranial ultrasound and CT studies performed during their hospitalization. Initially, subtle changes of diffuse brain edema were present but with no ventricular compression. A second phase revealed progressive brain edema with ventricular compression. A third phase with enlarging ventricles indicates developing encephalomalacia. Occasionally cyst formation may be noted within the cerebral white matter, a phenomenon initially more readily evident by ultrasound.