Perinatal characteristics of fetuses with borderline ventriculomegaly detected by routine ultrasonographic screening of low-risk populations

Comprehensive Assessment of Fetal Bilateral Ventriculomegaly Based on Genetic Disorders, Cytomegalovirus Infection, Extra Prenatal Imaging and Pregnancy Outcomes in a Tertiary Referral Center

Objective

This retrospective study aimed to systematically evaluate the genetic disorders, cytomegalovirus (CMV) infection, extra ultrasound findings and outcomes of fetuses with bilateral ventriculomegaly (BVM).

Methods

Data from pregnancies with fetal BVM were obtained between 2014 and 2020. The cases were divided into groups of isolated bilateral ventriculomegaly (IBVM) and non-isolated bilateral ventriculomegaly (NIBVM) according to the presence of extra prenatal imaging. Subgroups of mild, moderate, and severe were determined according to lateral ventricle widths. The NIBVM group was further classified into pregnancies with soft markers, non-structural abnormalities, and structural abnormalities.

Results

A total of 353 pregnancies were enrolled, including 153 cases of IBVM and 200 cases of NIBVM. Conventional karyotyping was performed on 192 samples, and 15 cases of numerical abnormalities and 3 cases of unbalanced structural abnormalities were identified. Chromosomal microarray analysis (CMA) was concurrently performed on 108 of them and revealed additional 5 cases (4.7%) of copy number variants with clinical significance. CMV DNA testing was performed on 154 of the 192 cases that underwent invasive prenatal diagnosis, and a positive result was found in 2 (1.3%) cases. In the IBVM group, the percentage of favorable prognosis in the mild, moderate and severe pregnancies were 94.4%, 79.2%, and 4.8%, respectively, and the termination of pregnancy (TOP) rates were 4.6%, 20.8%, and 85.7%, respectively. In both the mild and moderate NIBVM, the TOP rates progressively increased and the favorable prognosis survival rates progressively decreased relative to the soft markers, non-structural abnormalities, and structural abnormalities, respectively. Approximately 94.1% of severe NIBVM ended in termination.

Conclusion

Genetic disorders and fetal infection are important etiology of BVM. CMA is highly recommended for genetic disorders’ evaluation. Pregnancies with severe BVM always ended in TOP, while in mild-to-moderate NIBVM, prenatal imaging by ultrasound and/or MRI plays important roles in the pregnancy outcomes.

Early elective delivery for fetal ventriculomegaly: are neurosurgical and medical complications mitigated by this practice?

PURPOSE

Antenatally diagnosed ventriculomegaly (VM) requires the balance of risks of neurological injury with premature delivery. The purpose of this study was to evaluate outcomes related to early elective delivery due to fetal VM at our institution.

METHODS

We retrospectively assessed 120 babies (2008-2012) with antenatally diagnosed fetal VM. Inclusion criteria for ("early") cohort were (1) elective delivery occurred for expedited neurosurgical intervention between 32 and 36 weeks EGA and (2) fetal VM noted on official antenatal ultrasound. The comparative "near term" cohort differed only in that delivery occurred at 37+ weeks EGA. Statistical significance for comparative analyses set a priori at p < 0.05.

RESULTS

Babies electively delivered early had a lower birthweight (p < 0.0001), greater ventricle width (p < 0.0001), and underwent initial CSF diversion sooner (p = 0.014). The early cohort (n = 22), compared to near term (n = 50), had a lower birthweight (p < 0.0001), greater ventricle width (p < 0.0001), and underwent initial CSF diversion sooner (p = 0.014). The early cohort required more repeat procedures: (45 vs. 22% p = 0.021), and VPS removals after VPS infections (41 vs. 12%, p = 0.010). Additionally, newborn respiratory failure (32 vs. 6%, p = 0.037) was more common. Finally, of four babies who died in the early cohort, 2/4 died for prematurity-associated pulmonary hypoplasia.

CONCLUSIONS

While early elective delivery for fetal VM expedites intervention for rapidly expanding ventricles, few benefits were identified. Our study concluded those infants that were delivered earlier had increased VPS infections, repeat neurosurgical procedures, and medical co-morbidities. A multi-institutional prospective observational study would be needed in order to confirm the clinical implications of such practice.

Perinatal and long-term outcomes in fetuses diagnosed with isolated unilateral ventriculomegaly: systematic review and meta-analysis

OBJECTIVES

The majority of studies on fetal ventriculomegaly have focused on the perinatal and long-term outcomes in fetuses with an antenatal diagnosis of bilateral ventriculomegaly. The aim of this study was to undertake a systematic review and meta-analysis to quantify the perinatal and long-term outcomes in fetuses diagnosed in the second or third trimester of pregnancy with isolated unilateral ventriculomegaly.

METHODS

MEDLINE, EMBASE and The Cochrane Library were searched electronically. Outcomes investigated included incidence of aneuploidy, congenital infection, progression of ventriculomegaly, associated brain and extracerebral abnormalities in the apparently isolated cases and neurodevelopmental delay in both apparently and truly isolated cases. Sensitivity analysis was performed according to whether the ventriculomegaly was mild/moderate (atrial width < 15 mm) or severe (atrial width ≥ 15 mm). Reference lists within relevant articles and reviews were hand-searched for additional reports. Cohort and case-control studies were included. Meta-analysis of proportions was used, and between-study heterogeneity was assessed using the I² test.

RESULTS

The search yielded 2053 citations. The full text was retrieved for 202, and 11 studies were included in the systematic review. In fetuses with apparently isolated unilateral ventriculomegaly, no chromosomal abnormalities were identified and the pooled prevalence of congenital infection was 8.2% (95% CI, 3.6-14.5%). The pooled prevalence of additional brain abnormalities detected prenatally and postnatally by magnetic resonance imaging was 5.1% (95% CI, 0.2-16.1%) and 6.4% (95% CI, 0.3-19.4%), respectively. The pooled prevalence of abnormal neurodevelopment was 5.9% (95% CI, 2.2-11.2%) in apparently isolated cases with an atrial width of < 15 mm, and it was 7.0% (95% CI, 3.2-12.2%) in fetuses with truly isolated unilateral ventriculomegaly. Most cases with apparently isolated ventriculomegaly were classified as mild/moderate (93.5%) and therefore the outcomes in this group were similar to those in the whole cohort of apparently isolated ventriculomegaly.

CONCLUSIONS

The prevalence of aneuploidy, congenital infection and neurodevelopmental delay in fetuses with a prenatal diagnosis of isolated unilateral ventriculomegaly is likely to be low. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.