The utility of infection screening in isolated mild ventriculomegaly: an observational retrospective study on 141 fetuses

[Research Progress in Magnetic Resonance Imaging of Fetal Ventriculomegaly]

Fetal ventriculomegaly is a central nervous system disorder commonly seen in prenatal imaging, and the prognosis ranges from normal health to severe dysfunction. Currently, fetal predictive markers associated with postpartum individual neurodevelopmental function are still not available, which increases the difficulty of prenatal diagnosis and clinical management. Constant advancements in magnetic resonance imaging (MRI) technology have brought better accuracy and reliability of MRI applied in the diagnosis, prognosis assessment, and etiology investigation of ventriculomegaly. MRI plays a critical role in prognostic management and prenatal consultation. Nevertheless, due to the potential safety hazards and economic and technical constraints of MRI, it is not the first choice for prenatal imaging diagnosis. Moreover, there are different opinions regarding the measurement results and grading criteria of ultrasound and MRI. At present, it is accepted that three-dimensional volume may provide reliable information for prognosis. However, accurate segmentation and measurement of brain structure remain serious challenges, and no consensus on the MRI measurement of lateral ventricle volume has been reached. In this paper, based on the latest research reports from China and around the world, we reviewed the progress in applying MRI in the prenatal diagnosis and treatment of ventriculomegaly. This review offers a theoretical foundation for further exploration of the role of lateral ventricle volume measurement in disease diagnosis and management. We suggest that researchers combine two-dimensional width with three-dimensional volume in the future to identify the optimal cutoff value for prognostic prediction of fetal ventriculomegaly.

Prenatal detection of mild fetal ventriculomegaly - a systematic review of the modern literature

INTRODUCTION

While mild fetal ventriculomegaly is frequently observed as an incidental and benign finding, it is also known to be linked with structural, genetic, and neurodevelopmental abnormalities. The objective of this study was to conduct a systematic review of the existing literature in order to evaluate the association between apparently isolated fetal mild ventriculomegaly with the presence of additional structural defects detected by fetal brain MRI, chromosomal or other genetic anomalies, and neurodevelopmental delay.

METHODS

This systematic review was designed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Modern literature was searched from January 1, 2011, to July 31, 2023.

RESULTS

23 studies were included, comprising a total of 2590 patients. Nine studies assessed the association between fetal mild ventriculomegaly and neurodevelopmental impairment, including 536 cases, with normal neurodevelopmental outcomes ranging from 64% to 96.5%. Ten studies evaluated the additive value of fetal MRI, including 1266 fetuses, with the detection rate of additional brain defects that eventually altered the clinical management ranging from 0% to 19.5%. Seven studies investigated the association of mild ventriculomegaly with the presence of underlying chromosomal or genetic conditions, including 747 cases, with the rate ranging from 1.1% to 15.4%.

CONCLUSION

The prevalence of aneuploidy and genetic abnormalities in ventriculomegaly, especially in isolated cases, is reported to be quite low and the incidence of neurodevelopmental delay appears to be similar to that of the general population in cases that are apparently and truly isolated.

Follow-up outcome analysis of 324 cases of early-onset and late-onset mild fetal ventriculomegaly: a retrospective cohort study

BACKGROUND

Mild fetal ventriculomegaly (VM) is a nonspecific finding common to several pathologies with varying prognosis and is, therefore, a challenge in fetal consultation. We aimed to perform a constant, detailed analysis of prenatal findings and postnatal outcomes in fetuses with early-onset and late-onset mild ventriculomegaly, and provide a new evidence basis and new perspective for prenatal counseling.

METHODS

This is a retrospective cohort study of women with a diagnosis of mild fetal VM between January 2018 and October 2020. The population was divided into two groups according to the gestational ages (GAs) at initial diagnosis: the early-onset group (diagnosed at/before 24+6 weeks) and the late-onset group (diagnosed after 24+6 weeks). Clinical data and pregnancy outcomes were obtained from hospital records. The children's neurodevelopment status was assessed using the Ages and Stages Questionnaire, Third Edition (ASQ-3) and telephone interviews.

RESULTS

Our study cohort comprised 324 fetuses, out of which 94 (29%) were classified as early-onset group and 230 (71%) late-onset group. Early-onset group was more likely to have concurrent additional abnormalities, whereas in the late-onset group, isolated enlargement was more common (P = 0.01). Unilateral enlargement was more common in the late-onset group (P = 0.05), and symmetrical enlargement in the early-onset group (P < 0.01). In addition, early-onset mild VM cases were more likely to have intrauterine progression (P = 0.03), and many had a higher proportion of complex multisystem abnormalities. Compared with the late-onset group, the early-onset group was more often associated with congenital brain structure malformations. Approximately 11% of fetuses with mild VM had postnatal neurodevelopmental delay/disorders, and the risk was higher in the early-onset group (19.4% vs. 7.4%). Regression analysis showed that the GA at first diagnosis, non-isolated, and intrauterine progression significantly correlated with neurodevelopmental abnormalities.

CONCLUSIONS

Early-onset and late-onset mild VM had significantly different ultrasound features and outcomes. Early-onset mild VM may have more complex potential abnormalities and are more likely to predict poor prognosis than the late-onset.

Percutaneous fetal endoscopic third ventriculostomy for severe isolated cerebral ventriculomegaly

OBJECTIVE

To demonstrate the feasibility and preliminary results of percutaneous fetal endoscopic third ventriculostomy (ETV) in human fetuses (pfETV) with isolated progressive and/or severe bilateral cerebral ventriculomegaly (IPSBV).

METHODS

The initial results of pfETV for IPSBV were described. Perioperative, perinatal and postnatal variables were described. The Ages and Stages Questionnaire (ASQ-3), 3rd edition (ASQ-3) was used for follow-up of all infants.

RESULTS

Successful pfETV was performed in 10/11 (91%) fetuses, at a median gestational age (GA) of 28.7 weeks (25.3-30.7). There were no perioperative complications. After pfETV, 70% (7/10) of the fetuses had a decreased or stabilized lateral ventricle atria|lateral ventricle's atria. The median GA at delivery was 38.2 weeks (35.9-39.3). There were no perinatal complications. The postnatal ventriculoperitoneal shunt rate was 80% (8/10). Among neonates/infants who had prenatal stabilization or a decrease in the LVAs, 4 (4/7: 57.1%) had abnormal scores on the ASQ-3. Among neonates/infants that experienced prenatal increases in the LVAs, all of them (3/3: 100%) had abnormal scores on the ASQ-3.

CONCLUSION

Percutaneous ETV is feasible in human fetuses with progressive and/or severe cerebral ventriculomegaly and seems to be a safe procedure for both the mother and the fetus.

Automatic Ventriculomegaly Detection in Fetal Brain MRI: A Step-by-Step Deep Learning Model for Novel 2D-3D Linear Measurements

In this study, we developed an automated workflow using a deep learning model (DL) to measure the lateral ventricle linearly in fetal brain MRI, which are subsequently classified into normal or ventriculomegaly, defined as a diameter wider than 10 mm at the level of the thalamus and choroid plexus. To accomplish this, we first trained a UNet-based deep learning model to segment the brain of a fetus into seven different tissue categories using a public dataset (FeTA 2022) consisting of fetal T2-weighted images. Then, an automatic workflow was developed to perform lateral ventricle measurement at the level of the thalamus and choroid plexus. The test dataset included 22 cases of normal and abnormal T2-weighted fetal brain MRIs. Measurements performed by our AI model were compared with manual measurements performed by a general radiologist and a neuroradiologist. The AI model correctly classified 95% of fetal brain MRI cases into normal or ventriculomegaly. It could measure the lateral ventricle diameter in 95% of cases with less than a 1.7 mm error. The average difference between measurements was 0.90 mm in AI vs. general radiologists and 0.82 mm in AI vs. neuroradiologists, which are comparable to the difference between the two radiologists, 0.51 mm. In addition, the AI model also enabled the researchers to create 3D-reconstructed images, which better represent real anatomy than 2D images. When a manual measurement is performed, it could also provide both the right and left ventricles in just one cut, instead of two. The measurement difference between the general radiologist and the algorithm (p = 0.9827), and between the neuroradiologist and the algorithm (p = 0.2378), was not statistically significant. In contrast, the difference between general radiologists vs. neuroradiologists was statistically significant (p = 0.0043). To the best of our knowledge, this is the first study that performs 2D linear measurement of ventriculomegaly with a 3D model based on an artificial intelligence approach. The paper presents a step-by-step approach for designing an AI model based on several radiological criteria. Overall, this study showed that AI can automatically calculate the lateral ventricle in fetal brain MRIs and accurately classify them as abnormal or normal.

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

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.

Ultrasound Findings of Fetal Infections: Current Knowledge

Infectious diseases during pregnancy are still a major cause of fetal mortality and morbidity worldwide. The most common teratogenic pathogens are cytomegalovirus (CMV), varicella-zoster virus (VZV), rubeovirus, parvovirus B19, herpes simplex virus (HSV), Toxoplasma gondii, Treponema pallidum and the emergent Zika virus (ZIKV). Ultrasound findings include cerebral anomalies, orbital defects, micrognathia, cardiac defects, hepatosplenomegaly, liver calcifications, abdominal anomalies, skin and limb anomalies, edema, placental and amniotic fluid anomalies and altered Doppler analyses. The classification of ultrasound markers of congenital infections by anatomical region is reported to guide differential diagnosis and prenatal care.

Prenatal work-up, associated anomalies and postnatal outcomes of foetuses with 9-9.9 mm cerebral ventricular atria width

OBJECTIVE

To analyse prenatal work-up, associated anomalies and postnatal outcomes of foetuses with cerebral lateral ventricular width 9-9.9 mm.

METHOD

This retrospective, observational, case-control study included 121 foetuses with initial presentation of isolated cerebral lateral ventricular width 9-9.9 mm detected during routine ultrasound scans, 21-24 weeks' gestation, in a tertiary referral centre, January 2001-December 2018. Controls included 123 foetuses with lateral ventricular width <9 mm measured under the same parameters. Clinical characteristics, obstetrical history, ultrasound findings, prenatal work-up and pregnancy outcomes were collected from medical records. Information about postnatal functional and neurodevelopmental sequelae were obtained from telephone-based questionnaires.

RESULTS

The study group had more males (82/116 (70.6%) versus 65/123 (52.8%), p = 0.004), more prenatal testing, including brain magnetic resonance imaging (28/116 (24.1%) versus 0/123 (0%), p < 0.001), echocardiography (46/116 (39.7%) versus 15/123 (12.2%), p < 0.001) and targeted anomaly scans (102/116 (87.9%) versus 1/123 (0.008%), p < 0.001). Long-term follow-up did not reveal more neurodevelopmental sequelae compared to controls. Gender-based analysis found more males with ventricular dilatation 9-9.9 mm treated for developmental delay compared to females with similar findings (15/82 (18.2%) versus 1/34 (2.9%), p = 0.010).

CONCLUSION

Foetuses with 9-9.9 mm cerebral lateral ventricular width versus <9 mm underwent more prenatal testing but had similar rates of neurodevelopmental sequelae.

A systematic review of maternal TORCH serology as a screen for suspected fetal infection

BACKGROUND

The acronym 'TORCH' refers to well-recognised causes of perinatal infections: toxoplasmosis, rubella, cytomegalovirus (CMV) and herpes simplex virus (HSV). A TORCH serology panel is often used to test for maternal primary infection following detection of ultrasound abnormalities in pregnancy.

AIM

This review aims to estimate the diagnostic yield of maternal TORCH serology in pregnancy following fetal ultrasound abnormalities.

MATERIALS AND METHODS

Primary studies published since 2000 that assessed maternal TORCH serology for suspected fetal infection and included information on indications for testing, definition of positive TORCH serology results, and perinatal outcomes were included.

RESULTS

Eight studies with a total of 2538 pregnancies were included. The main indications for testing were polyhydramnios, fetal growth restriction and hyperechogenic bowel. There were 26 confirmed cases of congenital CMV, of which 15 had multiple ultrasound abnormalities. There were no cases of congenital toxoplasmosis, rubella or HSV confirmed in any of the eight studies.

CONCLUSIONS

The clinical utility of TORCH serology for non-specific ultrasound abnormalities such as isolated fetal growth restriction or isolated polyhydramnios is low. It is time to retire the TORCH acronym and the reflex ordering of 'TORCH' panels, as their continued use obscures, rather than illuminates, appropriate investigation for fetal ultrasound abnormalities.

Diagnosis, management, and neurodevelopmental outcomes of fetal hydrocephalus: an observational prospective study

The etiology of fetal hydrocephalus is complex, and the outcome of fetal neurodevelopment after birth is also different. The purpose of this study is to conduct anti-infection of hydrocephalus fetuses with non-specific infection, and observe their neurodevelopment after birth, so as to provide clinical basis for further guidance and management of fetal hydrocephalus. Eighteen single pregnant women with fetal hydrocephalus confirmed by intrapartum ultrasonography in the Second Xiangya Hospital between July 1, 2019, and December 1, 2020, were included. Pelvis MRI, NITP, amniotic fluid/umbilical cord blood puncture, infection index, TORCH, and other examinations were completed during pregnancy. If the patient's infection index is elevated, the second-generation cephalosporin will be used for anti-infection therapy, and the development of fetal hydrocephalus, growth, and neurodevelopment after birth will be observed. Fetal hydrocephalus subsided in 3 cases (25%, 95% CI [0%, 53.7%]) remained stable in 6 cases (50%, 95% CI [16.8%, 83.2%]), progressed in 2 cases (16.7%, 95% CI [0%, 41.4%]), and terminated pregnancy in 1 case (8.7% [0%, 26.7%]). Of the 6 untreated patients, pregnancy was terminated in 3 (50%), hydrocephalus remained stable in 2 (33.3%), and spontaneous resolution in 1 case (16.7%). Fourteen patients delivered successfully, including 11 children with no obvious abnormalities in growth and development, 1 with mild growth retardation and 2 with moderate growth retardation. Anti-infective therapy in the case of non-specific infection or maternal infection can partially prevent the progression of hydrocephalus.

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.

Prognostic Analysis and Risk Factors Associated with Fetal Ventriculomegaly

BACKGROUND

This study aimed to investigate the clinical outcome and related risk factors of fetal lateral ventriculomegaly (VM).

METHODS

A retrospective analysis was performed on 255 cases diagnosed as fetal VM. Prenatal imaging examination was carried out. The pregnancy outcomes were investigated through follow-up. According to the prognosis of children, they were divided into case group and control group. Multivariate logistic regression was used to analyze the factors influencing the prognosis of hydrocephalus.

RESULTS

After excluding the cases with either loss of follow-up or incomplete information, 102 cases were followed up. Twelve cases with poor prognosis were set as the case group. According to the maternal age, gestational age, gender of children, and follow-up time, 3 cases were selected from the other 90 cases for each child in the case group, respectively, and selected as the control group. Paired comparative analysis was performed on 48 cases. Using prognosis as a dependent variable, multivariate logistic regression analysis of the statistically significant factors indicated that the change speed of width ratio (CSWR) and maximum lateral ventricular width (MW) were associated with fetal prognosis.

CONCLUSIONS

Our results suggested that CSWR and MW may have the value of predicting fetal prognosis.

Outcomes of Isolated Fetal Ventriculomegaly That Resolve In Utero

OBJECTIVE

Isolated fetal ventriculomegaly is often an incidental finding on antenatal ultrasound. It is benign in up to 90% of cases, although it can be associated with genetic, structural, and neurocognitive disorders. The literature suggests that over 40% of isolated mild ventriculomegaly will resolve in utero, but it is unclear if resolution decreases the associated risks.The aim of this study is to compare the fetal and neonatal genetic outcomes of ventriculomegaly that persists or resolves on subsequent ultrasound.

STUDY DESIGN

This is a retrospective cohort study of women diagnosed with isolated ventriculomegaly via fetal ultrasound at a tertiary referral center between 2011 and 2019. Patients were excluded if other structural anomalies were identified on ultrasound.

RESULTS

A total of 49 patients were included in the study, 19 in the resolved ventriculomegaly group and 30 in the persistent ventriculomegaly group. Women in the resolved ventriculomegaly group were more likely to be diagnosed earlier (24 vs. 28 weeks, p = 0.007). Additionally, they were more likely to have mild ventriculomegaly (63 vs. 84%, p = 0.15), and less likely to have structural neurological abnormalities diagnosed on postnatal imaging (5 vs. 17%, p = 0.384), although these were not statistically significant. Aneuploidy risk for resolved compared with persistent ventriculomegaly was similar (5 vs. 7%, p = 0.999).

CONCLUSION

This study suggests that resolution of isolated ventriculomegaly in utero may not eliminate the risk of genetic or chromosomal abnormalities in this population and may warrant inclusion as part of the counselling of these at-risk patients. Larger prospective studies are needed to confirm these findings.

KEY POINTS

· Ventriculomegaly is known to be associated with genetic and chromosomal abnormalities.. · Resolution of the ventriculomegaly in utero may not eliminate those risks.. · Patients with resolved ventriculomegaly should be offered aneuploidy screening or testing..

Correlation between mild fetal ventriculomegaly, chromosomal abnormalities, and copy number variations

BACKGROUND

Lateral ventriculomegaly is the most common abnormality of the fetal nervous system. This study investigated the incidence of chromosomal abnormalities and copy number variations (CNVs) in fetuses with mild ventriculomegaly (MV) based on various ultrasonic manifestations, identifying their corresponding features via ultrasound examination.

METHODS

A retrospective analysis was performed on ultrasound and neurosonogram (NSG) manifestations and genetic profiles of 334 cases with MV and invasive prenatal diagnosis.

RESULTS

Three hundred thirty-four cases with fetal MV were assessed via karyotyping. Further chromosomal microarray analysis (CMA) was performed in 182 cases with normal chromosome karyotypes; pathogenic chromosomal copy number variations (CNVs) were found in eight cases with a prevalence of 4.4% (8/182). In this study, the incidence rate of pathogenic abnormalities of chromosomes and CNVs was 5.7% (19/334). Based on whether lateral ventriculomegaly was complicated with other ultrasonic features, the 334 patients were divided into two groups: (1) 175 cases exhibited isolated ventriculomegaly (IVM; 52.4%, 175/334 group A) including two (1.1%, 2/175) with pathogenic chromosomal karyotype abnormalities-both trisomy 21; (2) 159 cases exhibited non-isolated ventriculomegaly (N-IVM; 47.6%, 159/334) with pathogenic chromosomal abnormalities and CNVs detected in17 cases (10.7%, 17/159). The N-IVM group was further divided into two groups: 105 cases exhibited MV with undetermined ultrasonic abnormalities (31.4%, 105/334, group B) with pathogenic chromosomal abnormalities and CNVs detected in eight cases (7.6%, 8/105); 54 cases exhibited MV with structural malformations (16.2%, 54/334, group C) of which nine cases (16.7%, 9/54) presented both pathogenic chromosomal abnormalities and CNVs, and five cases (55.6%, 5/9) were diagnosed with various cortical malformations. The pathogenicity rates of the IVM and N-IVM groups were statistically different (χ ²=14.159, p = 0.000). There were significant differences (χ²=7.992, p = 0.005) among groups A, B, and C.

CONCLUSIONS

Combinations of various ultrasonic abnormalities significantly affect the risk of pathogenic chromosomal abnormalities and CNVs in fetuses with MV. Cases involving cortical malformations require particular attention to the occurrence of pathogenic genetic abnormalities. When fetal MV is detected, a comprehensive ultrasound examination focusing on undetermined ultrasonic abnormalities is critical. Fetal NSG should be conducted to detect potential cerebral cortical malformation easily missed by routine ultrasound.

Prenatal diagnosis of chromosomal aberrations by chromosomal microarray analysis in foetuses with ventriculomegaly

Ventriculomegaly is considered to be linked to abnormal neurodevelopment outcome. The aim of this retrospective study was to investigate the current applications of chromosomal microarray analysis (CMA) in foetuses with ventriculomegaly. A total of 548 foetuses with ventriculomegaly detected by prenatal ultrasound underwent single nucleotide polymorphism (SNP) array testing and were subjected to long-term follow-up. The overall prevalence of chromosomal aberrations was 7.30% (40/548), including 4.20% (23/548) with pathogenic/likely pathogenic copy number variants. The incidence of chromosomal aberrations was significantly higher in foetuses with bilateral ventriculomegaly than in those with unilateral ventriculomegaly (10.56% vs. 5.71%, P = 0.040), in foetuses with non-isolated ventriculomegaly than in those with isolated ventriculomegaly (12.99% vs. 2.38%, P < 0.0001), and in foetuses with severe ventriculomegaly than in those with mild-to-moderate ventriculomegaly (23.08% vs. 6.51%, P = 0.005). The outcome in foetuses with mild ventriculomegaly was significantly better than in those with moderate ventriculomegaly (95.60% vs. 84.00%, P = 0.003). Thus, CMA should be regarded as the first-tier test for prenatal diagnosis of foetal ventriculomegaly, especially in foetuses with bilateral or non-isolated ventriculomegaly. The outcome of foetuses with mild ventriculomegaly is favourable; however, there is an increased risk of neurodevelopmental disabilities in foetuses with moderate ventriculomegaly.

Significance of isolated borderline ventriculomegaly

PURPOSE

Foetal ventriculomegaly (VM) is one of the most commonly diagnosed brain abnormalities. The aims of this study were to assess cases with isolated VM, describe the prenatal course and assess short- and long-term follow-up at the age of 2 years.

METHODS

We performed a retrospective analysis from our prenatal data base and included all children that were prenatally diagnosed with VM in our unit between 2008 and 2013 (n = 250). Prenatal management, postnatal outcome and neurologic development at the age of 2 years were evaluated.

RESULTS

A total of 106 children were born at our institution and were diagnosed prenatally with isolated borderline VM. A total of 1.9% (n = 2/106) was transferred to the neonatal unit. A total of 0.9% (n = 1/106) showed abnormal findings in postnatal brain ultrasound. A total of 1.9% (n = 2/106) showed mild neurologic abnormalities after birth, but none had to be seen by a neuropediatrician. At the follow-up at 2 years, 2.5% (n = 1/40) had an insertion of a shunt.

CONCLUSION

Based on our analysis, the majority of isolated borderline VM do not show short- or long-term neurological abnormalities. However, all cases of VM should be referred to a detailed prenatal ultrasound exam by a specialist.

Neurodevelopmental disorder in children believed to have isolated mild ventriculomegaly prenatally

OBJECTIVE

To estimate the prevalence of specific neurodevelopmental disorders in children believed to have isolated mild ventriculomegaly (IMV) prenatally in the second trimester of pregnancy, in order to optimize the counseling process.

METHODS

This was a nationwide registry-based study including all singleton pregnancies that had first- and second-trimester ultrasound scans in the period 1^st January 2008 to 1^st October 2014, identified in the Danish Fetal Medicine Database and local clinical databases in Denmark. All fetuses diagnosed prenatally with IMV (measurement of the atrium of the lateral ventricles, 10.0-15.0 mm) between 18 and 22 weeks' gestation were followed up in national patient registers until the age of 2-7 years. Information was obtained on the diagnoses of intellectual disability, cerebral palsy, autism spectrum disorder, epilepsy and impaired psychomotor development. Neurodevelopmental disorders were compared between those with postnatally confirmed IMV and a reference population of children in the same age range.

RESULTS

Of a cohort of 292 046 fetuses, 133 were found to have apparent IMV on the second-trimester scan for fetal malformations. In 11 cases, long-term follow-up was not possible owing to termination of pregnancy, spontaneous miscarriage, neonatal death or loss to follow-up. Of the 122 liveborn children followed up until 2-7 years, 15 were identified as having an additional abnormality while 107 were confirmed postnatally to have IMV. Of these 107 children, the diagnosis of a neurodevelopmental disorder was registered in six (5.6%), corresponding to an odds ratio of 2.64 (95% CI, 1.16-6.02), as compared with the reference population. The diagnoses were autism spectrum disorder, epilepsy and impaired psychomotor development. None of these 107 children was diagnosed with intellectual disability or cerebral palsy.

CONCLUSIONS

Our results show that a confirmed diagnosis of IMV was associated with an increased risk of a neurodevelopmental disorder, as compared with the reference population, but the absolute risk was low and there were no cases of intellectual disability or cerebral palsy. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Role of magnetic resonance imaging in fetuses with mild or moderate ventriculomegaly in the era of fetal neurosonography: systematic review and meta-analysis

OBJECTIVES

To report the rate of additional central nervous system (CNS) anomalies detected exclusively on prenatal magnetic resonance imaging (MRI) in fetuses diagnosed with isolated mild or moderate ventriculomegaly (VM) on ultrasound, according to the type of ultrasound protocol adopted (dedicated neurosonography vs standard assessment of the fetal brain), and to explore whether the diagnostic performance of fetal MRI in detecting such anomalies is affected by gestational age at examination and laterality and degree of ventricular dilatation.

METHODS

MEDLINE, EMBASE, CINAHL and Clinicaltrials.gov were searched for studies reporting on the prenatal MRI assessment of fetuses diagnosed with isolated mild or moderate VM (ventricular dilatation of 10-15 mm) on ultrasound. Additional anomalies detected only on MRI were classified as callosal, septal, posterior fossa, white matter, intraventricular hemorrhage, cortical, periventricular heterotopia, periventricular cysts or complex malformations. The rate of additional anomalies was compared between fetuses diagnosed on dedicated neurosonography, defined as a detailed assessment of the fetal brain, according to the International Society of Ultrasound in Obstetrics and Gynecology guidelines, and those diagnosed on standard fetal brain assessment. The rate of additional CNS anomalies missed on prenatal MRI and detected only at birth was calculated and compared between fetuses that had early (at or before 24 weeks' gestation) and those that had late (after 24 weeks) MRI. Subanalysis was performed according to the laterality (uni- vs bilateral) and degree (mild vs moderate, defined as ventricular dilatation of 10-12 and 13-15 mm, respectively) of ventricular dilatation. Whether MRI assessment led to a significant change in prenatal management was explored. Random-effects meta-analysis of proportions was used.

RESULTS

Sixteen studies (1159 fetuses) were included in the systematic review. Overall, MRI detected an anomaly not identified on ultrasound in 10.0% (95% CI, 6.2-14.5%) of fetuses. However, when stratifying the analysis according to the type of ultrasound assessment, the rate of associated anomalies detected only on MRI was 5.0% (95% CI, 3.0-7.0%) when dedicated neurosonography was performed compared with 16.8% (95% CI, 8.3-27.6%) in cases that underwent a standard assessment of the fetal brain in the axial plane. The overall rate of an additional anomaly detected only at birth and missed on prenatal MRI was 0.9% (95% CI, 0.04-1.5%) (I² , 0%). There was no difference in the rate of an associated anomaly detected only after birth when fetal MRI was carried out before, compared with after, 24 weeks of gestation (P = 0.265). The risk of detecting an associated CNS abnormality on MRI was higher in fetuses with moderate than in those with mild VM (odds ratio, 8.1 (95% CI, 2.3-29.0); P = 0.001), while there was no difference in those presenting with bilateral, compared with unilateral, dilatation (P = 0.333). Finally, a significant change in perinatal management, mainly termination of pregnancy owing to parental request, following MRI detection of an associated anomaly, was observed in 2.9% (95% CI, 0.01-9.8%) of fetuses undergoing dedicated neurosonography compared with 5.1% (95% CI, 3.2-7.5%) of those having standard assessment.

CONCLUSIONS

In fetuses undergoing dedicated neurosonography, the rate of a CNS anomaly detected exclusively on MRI is lower than that reported previously. Early MRI has an excellent diagnostic performance in identifying additional CNS anomalies, although the findings from this review suggest that MRI performed in the third trimester may be associated with a better detection rate for some types of anomaly, such as cortical, white matter and intracranial hemorrhagic anomalies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Current Controversies in Prenatal Diagnosis 1: Should MRI be performed on all fetuses with mild ventriculomegaly?

A ventricular diameter of 10 mm correlates with more than two standard deviations of the normal and hence is qualified as ventriculomegaly. The relevance of this is dependent on whether there are associated infectious, genetic, or structural problems. The chance for neurodevelopmental delay in isolated ventriculomegaly less than 15 mm is 7.9% (4.7-11.1), and less if it is unilateral. It can be further divided in mild (10-12) or moderate (13-15), though this is not widely accepted. As part of the workup, structural assessment today may include ultrasound or magnetic resonance imaging, or both. Discussants agreed that the diagnostic performance of both methods is as good as the expertise with which the images are acquired and interpreted. Discussants agreed that when the initial neurosonogram is normal, the likelihood of finding significant findings on MRI is low. Nevertheless, some anomalies may only be picked up or better worked out by fetal MRI. In utero follow-up is advocated, as progression may indicate a poorer outcome, and some conditions are only obvious late in pregnancy. Most benefit for future patients is expected from appropriate training in prenatal neuroimaging.

Mild ventriculomegaly from fetal consultation to neurodevelopmental assessment: A single center experience and review of the literature

OBJECTIVE

The aim of our study was to determine the outcome of fetuses with isolated mild ventriculomegaly, with prenatal imaging work-up, prenatal consultation, delivery and clinical follow-up performed in a single tertiary referring center.

METHODS

Fetuses with isolated and non-progressive mild ventriculomegaly (10-15 mm) were included in the study. Inclusion criteria were as follows: singleton pregnancies, normal chromosomal analysis, normal serological evaluation of TORCH, fetal ultrasound and MRI excluding additional CNS or extra-CNS malformations. The prenatal consultation consisted in discussing the prognosis of ventriculomegaly, according to the literature. The postnatal follow-up protocol included a neuroradiological investigation (cranial ultrasound or MRI), neurological and pediatric examinations. The Griffiths Scales were used to assess the neurodevelopmental outcome.

RESULTS

Thirty newborns were included in follow-up. The postnatal neuroradiological investigations confirmed the ventriculomegaly as an isolated finding in all cases except one. Nineteen children were available for formal neurodevelopmental testing. In our case series, 93.3% of the children had a favorable outcome or mild anomalies. Two children (6.6%) with mild ventriculomegaly were diagnosed as having rare genetic conditions. The Griffiths developmental quotients were normal (mean General Quotient 98.3) at the latest assessment (mean age 20.8 months) in all but one case.

DISCUSSION

Most children in our case series had a favorable outcome, as described in the literature. Even though a large quantity of data is now available on ventriculomegaly, fetal consultation remains challenging and requires caution. The diagnostic work-up of pregnancies diagnosed with mild ventriculomegaly must be very meticulous and include TORCH evaluation, microarray, serial ultrasounds to exclude progression, and a fetal MRI. However, despite accurate screening, there are more complex conditions in which ventriculomegaly can be the only non-specific finding in fetal life, making postnatal follow up mandatory.

Mild fetal ventriculomegaly: diagnosis, evaluation, and management

Ventriculomegaly is defined as dilation of the fetal cerebral ventricles and is a relatively common finding on prenatal ultrasound. The purpose of this document is to review the diagnosis, evaluation, and management of mild fetal ventriculomegaly. When enlargement of the lateral ventricles (≥10 mm) is identified, a thorough evaluation should be performed, including detailed sonographic evaluation of fetal anatomy, amniocentesis for karyotype and chromosomal microarray analysis, and a workup for fetal infection. In some cases, fetal magnetic resonance imaging may identify other central nervous system abnormalities and should be considered when this technology as well as expert interpretation is available. Follow-up ultrasound examination should be performed to assess for progression of the ventricular dilation. In the setting of isolated ventriculomegaly of 10-12 mm, the likelihood of survival with normal neurodevelopment is >90%. With moderate ventriculomegaly (13-15 mm), the likelihood of normal neurodevelopment is 75-93%. The following are Society for Maternal-Fetal Medicine recommendations: We suggest that ventriculomegaly be characterized as mild (10-12 mm), moderate (13-15 mm), or severe (>15 mm) for the purposes of patient counseling, given that the chance of an adverse outcome and potential for other abnormalities are higher when the ventricles measure 13-15 mm vs 10-12 mm (GRADE 2B); we recommend that diagnostic testing (amniocentesis) with chromosomal microarray analysis should be offered when ventriculomegaly is detected (GRADE 1B); we recommend testing for cytomegalovirus and toxoplasmosis when ventriculomegaly is detected, regardless of known exposure or symptoms (GRADE 1B); we suggest that magnetic resonance imaging be considered in cases of mild or moderate fetal ventriculomegaly when this modality and expert radiologic interpretation are available; magnetic resonance imaging is likely to be of less value if the patient has had a detailed ultrasound performed by an individual with specific experience and expertise in sonographic imaging of the fetal brain (GRADE 2B); we recommend that timing and mode of delivery be based on standard obstetric indications (GRADE 1C); we recommend that with isolated mild ventriculomegaly of 10-12 mm, after a complete evaluation, women be counseled that the outcome is favorable, and the infant is likely to be normal (GRADE 1B); we recommend that with isolated moderate ventriculomegaly of 13-15 mm, after a complete evaluation, women be counseled that the outcome is likely to be favorable but that there is an increased risk of neurodevelopmental disabilities (GRADE 1B).

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.