Isolated mild fetal cerebral ventriculomegaly: a retrospective analysis of 26 cases.

We retrospectively studied 26 fetuses with isolated mild cerebral ventriculomegaly diagnosed between 1992 and 1998 and defined by a lateral ventricular atrial diameter of 10-15 mm without any other cerebral anomaly. Our objectives were to determine maternal risk factors, to evaluate complementary investigations, to assess developmental prognosis and to propose possible management. During pregnancy 10/26 patients had regressive ventriculomegalies, ten remained borderline at birth and six were confirmed postnatally. No maternal risk factors were identified. Prenatal investigations were carried out in 69% of cases but in only a few cases supplied any information. Postnatal examinations revealed one case of Down syndrome and one of porencephaly. Four children were lost to follow-up. In the 22 other cases, four had developmental delay. Early and unexplained mild ventriculomegaly appears to have a good prognosis. If ventriculomegaly is persistent, prenatal management should be carried out to investigate chromosomal abnormalities, viral infection, and fetal cerebral parenchymal damage. A long postnatal clinical follow-up is required.