The outcome of fetal ventriculomegaly

Over a 5 year period 38 cases of fetal ventriculomegaly were diagnosed at Queen's Medical Centre, Nottingham. There were 12 cases of spina bifida and all patients opted for a termination of pregnancy. There were 15 cases of isolated ventriculomegaly comprising seven cases of aqueduct stenosis, four abnormalities of the corpus callosum, one cavum septum pellucidum cyst, one case of porencephaly and two cases of mild lateral ventricular dilatation. The fetuses in this group had a relatively good outcome with five babies showing normal development, three with mild development delay and one with moderate developmental delay. There was one stillbirth and five patients opted for a termination of pregnancy. Associated abnormalities were seen in seven cases and these carried a poor prognosis with one fetus stillborn, one neonatal death, and three patients opted for a termination of pregnancy. Two babies were liveborn, one has severe developmental delay and the other one is normal. The four remaining cases included two Dandy Walker syndrome, one brain tumour and one case of subdural haemorrhage. There were three terminations of pregnancy and one stillbirth in this group. The outcome of fetal ventriculomegaly depends on the presence of associated abnormalities which carry a poor prognosis. It also depends on the timing of the diagnosis as most patients will opt for a termination of pregnancy if the diagnosis is made before 24 weeks gestation. A review of the literature reveals that, excluding terminations, fetuses with isolated ventriculomegaly have an 80% chance of survival and a 50% chance of normal development.