[Fetal cerebral ventriculomegaly. Etiology and outcome, report of 141 cases].

OBJECTIVE: To present the different etiologies of fetal cerebral ventriculomegaly (VA) and try to evaluate prognosis. MATERIALS AND METHODS: A retrospective analysis was made in 141 cases of fetal cerebral ventriculomegaly diagnosed in our obstetrics department between January 1988 and December 1996. RESULTS: Mean gestational age at diagnosis was 24.8 weeks. Myelomeningoceles were the most frequent etiology (50 cases, 36%), usually diagnosed late in pregnancy (25 weeks gestation). Termination of pregnancy was the most frequent outcome. Agenesis of the corpus callosum (ACC) was observed in 16 cases (11%), 8 of them being diagnosed before birth. This etiology has been an important diagnostic problem until recent years. The advent of improved imaging techniques has facilitated diagnostic procedures. Thus in 1996, the 4 ACC were all diagnosed by prenatal ultrasound. The 8 live infants presented developmental retardation. Termination of pregnancy has been performed more and more frequently in accordance with parent wishes. In 6 cases (4%), the etiology was congenital infection. When a chromosome anomaly was found (7%), ventriculomegaly was always associated with other ultrasonographic anomalies. Ventriculomegaly was associated with other malformations in 23% of the cases but only 17% were discovered prenatally; all the live infants but one had severe neurological impairment. Ventriculomegaly was considered to be the unique anomaly in 37% of the prenatal cases and was truly unique in 24%, an etiology being found in 6%. No explanation was found in 18%. The outcome of live infants is known in 139 cases (2 children lost to follow-up) after a 6 month to 6 year follow-up. Overall prognosis was severe as among the 42 infants (30%), 14 (10%) are well including 12 who had ventriculomegaly alone. CONCLUSION: Prenatal diagnosis of ventriculomegaly implies a severe prognosis. Only children presenting limited ventriculomegaly alone have normal neurological development. In case of ventriculomegaly, clinicians must search carefully for other anomalies, always associated with poor prognosis.