Fetal cerebral ventriculomegaly: What do we tell the prospective parents?

Abstract

Fetal cerebral ventriculomegaly is a relatively common finding, observed during approximately 1% of obstetric ultrasounds. In the second and third trimester, mild (≥10 mm) and severe ventriculomegaly (≥15 mm) are defined according to the measurement of distal lateral ventricles that is included in the routine sonographic examination of central nervous system. A detailed neurosonography and anatomy ultrasound should be performed to detect other associated anomalies in the central nervous system and in other systems, respectively. Fetal MRI might be useful when neurosonography is unavailable or suboptimal. The risk of chromosomal and non‐chromosomal genetic disorders associated with ventriculomegaly is high, therefore invasive genetic testing, including microarray, is recommended. Screening for prenatal infections, in particular cytomegalovirus and toxoplasmosis, should also be carried out at diagnosis. The prognosis is determined by the severity of ventriculomegaly and/or by the presence of co‐existing abnormalities. Fetal ventriculoamniotic shunting in progressive isolated severe ventriculomegaly is an experimental procedure. After delivery, ventricular‐peritoneal shunting or ventriculostomy are the two available options to treat hydrocephalus in specific conditions with similar long‐term outcomes. A multidisciplinary fetal neurology team, including perinatologists, geneticists, pediatric neurologists, neuroradiologists and neurosurgeons, can provide parents with the most thorough prenatal counseling. This review outlines the latest evidence on diagnosis and management of pregnancies complicated by fetal cerebral ventriculomegaly.

Molecular Diagnostic Yield of Exome Sequencing in Patients With Congenital Hydrocephalus

“…To limit nonspecific and benign cases, we included cases with severe ventriculomegaly and excluded cases denoted as mild, moderate, or ungraded and unspecified. We excluded fetal cases with mild or moderate ventriculomegaly because the majority (>90% of mild cases) of these have been shown to be associated with typical neurodevelopmental outcomes and are nonspecific to CH …”

“…We excluded fetal cases with mild or moderate ventriculomegaly because the majority (>90% of mild cases) of these have been shown to be associated with typical neurodevelopmental outcomes and are nonspecific to CH. 21 The inclusion of ventriculomegaly cases in this CH meta-analysis raises certain concerns.…”

Counseling in fetal medicine: update on mild and moderate fetal ventriculomegaly

“…Occurrence of associated anomalies represents another risk factor for adverse outcome in fetuses with isolated VM at the time of diagnosis. Additional anomalies not diagnosed at the first scan can occur in up to 12% of fetuses with VM, although this figure is extrapolated from old series 7,10,41 . In a more recent study of fetuses with normal karyotype undergoing neurosonography, associated anomalies occurred after birth in 3.9% of cases, and mainly constituted migration disorders, such as polymicrogyria 33 .…”

“…On this basis, the definition of isolated VM before birth is presumptive. Despite that, in view of the very low risk of adverse neurodevelopmental outcome in fetuses with isolated findings, negative genetic and infectious workup and no additional anomalies at follow‐up, some authors suggest that ventricular dilatation less than 12 mm in the third trimester of pregnancy can be considered a normal variant 41 .…”

Addressing expectations of therapeutic options for children with hydrocephalus—A comment on “Fetal Cerebral Ventriculomegaly. What do we tell the prospective parents?”

“…What do we tell the prospective parents?” by Giorgione et al. recently published in this journal 1 . We congratulate the authors on providing thoughtful and practical suggestions on diagnostic workup and prenatal counseling for future parents when a fetal cerebral ventriculomegaly is diagnosed on obstetric ultrasound examination.…”