Differential diagnosis and treatment of small subdural effusion in children.

Twenty infants with peripheral low density areas over the frontal lobes in CT scans that resembled cortical atrophy or early communicating hydrocephalus are reported. Most cases presented minimal developmental retardation and a slightly bulging fon tanelle. In many cases, peripheral hypodensity over the frontal lobes disappeared and the infants' development eventually reached normal levels without operations. The lesion might be called "infantile benign subdural effusion" and should be treated conservatively. Two illustrative cases are presented and the differential diagnosis is discussed.