Perinatal and neurodevelopmental outcomes of fetal isolated ventriculomegaly: a systematic review and meta-analysis.

Background: Isolated fetal ventriculomegaly can have a range of consequences, ranging from mild neurodevelopmental delay to perinatal death; the extent of these consequences often depend on the severity of ventriculomegaly. This systematic review and meta-analysis aims to investigate the impact of the degree of ventricular dilatation on the risk of neurodevelopmental delay and adverse perinatal outcomes in fetuses diagnosed with isolated fetal ventriculomegaly from gestational week 15 onwards. Methods: PubMed, Embase, Scopus and the Cochrane Library were searched electronically to identify studies investigating the prognosis of mild and/or severe isolated fetal ventriculomegaly. Articles were included if they reported neurodevelopmental or perinatal outcomes in fetuses prenatally diagnosed with isolated fetal ventriculomegaly from week 15 of gestation and onwards. Studies were excluded if they reported on non-isolated ventriculomegaly (IVM), failed to specify the degree of ventriculomegaly, were non-English papers, animal studies or published outside of the 21-year period of interest. Study quality was assessed by two independent reviewers using a modified version of the Newcastle-Ottawa Quality Assessment Scale. Ventriculomegaly was defined as either mild or severe when ventricular diameter measured as 10-15 or >15 mm, respectively. Meta-analyses were conducted for adverse neurodevelopmental outcome, intrauterine fetal demise and infant mortality. Results: Following the removal of duplicates, the search yielded 2,452 citations, of which 23 studies were included and 8 were eligible for meta-analysis. There were 767 and 347 cases of mild and severe isolated fetal ventriculomegaly, respectively. Adverse outcomes were consistently reported at a higher rate in severe cases than mild. The relative risks of adverse neurodevelopmental outcome, intrauterine fetal demise and infant mortality were 4.24 [95% confidence interval (CI): 2.46-7.30], 4.46 (95% CI: 1.64-12.11) and 6.02 (95% CI: 1.73-21.00), respectively, upon comparison of mild versus severe cases of isolated fetal ventriculomegaly. Conclusions: The likelihood of adverse neurodevelopmental and perinatal outcomes, including intrauterine and infant mortality, is increased in severe isolated fetal ventriculomegaly compared to mild isolated fetal ventriculomegaly.