Fetal cerebral ventriculomegaly: outcome in 176 cases

Expanding the phenotypic spectrum of LIG4 pathogenic variations: neuro-histopathological description of 4 fetuses with stenosis of the aqueduct

Severe ventriculomegaly is a rare congenital brain defect, usually detected in utero, of poor neurodevelopmental prognosis. This ventricular enlargement can be the consequence of different mechanisms: either by a disruption of the cerebrospinal fluid circulation or abnormalities of its production/absorption. The aqueduct stenosis is one of the most frequent causes of obstructive ventriculomegaly, however, fewer than 10 genes have been linked to this condition and molecular bases remain often unknown. We report here 4 fetuses from 2 unrelated families presenting with ventriculomegaly at prenatal ultra-sonography as well as an aqueduct stenosis and skeletal abnormalities as revealed by fetal autopsy. Genome sequencing identified biallelic pathogenic variations in LIG4, a DNA-repair gene responsible for the LIG4 syndrome which associates a wide range of clinical manifestations including developmental delay, microcephaly, short stature, radiation hypersensitivity and immunodeficiency. Thus, not only this report expands the phenotype spectrum of LIG4-related disorders, adding ventriculomegaly due to aqueduct stenosis, but we also provide the first neuropathological description of fetuses carrying LIG4 pathogenic biallelic variations.

White matter changes in fetal brains with ventriculomegaly

Introduction

Ventriculomegaly (VM) is a fetal brain malformation which may present independently (isolated form) or in association with different cerebral malformations, genetic syndromes or other pathologies (non-isolated form).

Methods

This paper aims to study the effect of ventriculomegaly on the internal tridimensional architecture of fetal brains by way of Klingler's dissection. Ventriculomegaly was diagnosed using fetal ultrasonography during pregnancy and subsequently confirmed by necropsy. Taking into consideration the diameter of the lateral ventricle (measured at the level of the atrium), the brains were divided into two groups: moderate ventriculomegaly (with atrial diameter between 13 and 15 mm) and severe ventriculomegaly (with atrial diameter above 15 mm).

Results and discussion

The results of each dissection were described and illustrated, then compared with age-matched reference brains. In the pathological brains, fascicles in direct contact with the enlarged ventricles were found to be thinner and displaced inferiorly, the opening of the uncinate fasciculus was wider, the fornix was no longer in contact with the corpus callosum and the convexity of the corpus callosum was inverted. We have studied the prevalence of neurodevelopmental delay in children born with ventriculomegaly in the literature and discovered that a normal developmental outcome was found in over 90% of the mild VM cases, approximately 75% of the moderate and 60% in severe VM, with the correlated neurological impairments ranging from attention deficits to psychiatric disorders.

Characterisation of ASD traits among a cohort of children with isolated fetal ventriculomegaly

Fetal ventriculomegaly is the most common antenatally-diagnosed brain abnormality. Imaging studies in antenatal isolated ventriculomegaly demonstrate enlarged ventricles and cortical overgrowth which are also present in children with autism-spectrum disorder/condition (ASD). We investigate the presence of ASD traits in a cohort of children (n = 24 [20 males/4 females]) with isolated fetal ventriculomegaly, compared with 10 controls (n = 10 [6 males/4 females]). Neurodevelopmental outcome at school age included IQ, ASD traits (ADOS-2), sustained attention, neurological functioning, behaviour, executive function, sensory processing, co-ordination, and adaptive behaviours. Pre-school language development was assessed at 2 years. 37.5% of children, all male, in the ventriculomegaly cohort scored above threshold for autism/ASD classification. Pre-school language delay predicted an ADOS-2 autism/ASD classification with 73.3% specificity/66.7% sensitivity. Greater pre-school language delay was associated with more ASD symptoms. In this study, the neurodevelopment of children with isolated fetal ventriculomegaly, associated with altered cortical development, includes ASD traits, difficulties in sustained attention, working memory and sensation-seeking behaviours.

Comprehensive quantitative analyses of fetal magnetic resonance imaging in isolated cerebral ventriculomegaly

Isolated cerebral ventriculomegaly (IVM) is the most common prenatally diagnosed brain anomaly occurs in 0.2-1 % of pregnancies. However, knowledge of fetal brain development in IVM is limited. There is no prenatal predictor for IVM to estimate individual risk of neurodevelopmental disability occurs in 10 % of children. To characterize brain development in fetuses with IVM and delineate their individual neuroanatomical variances, we performed comprehensive post-acquisition quantitative analysis of fetal magnetic resonance imaging (MRI). In volumetric analysis, brain MRI of fetuses with IVM (n = 20, 27.0 ± 4.6 weeks of gestation, mean ± SD) had revealed significantly increased volume in the whole brain, cortical plate, subcortical parenchyma, and cerebrum compared to the typically developing fetuses (controls, n = 28, 26.3 ± 5.0). In the cerebral sulcal developmental pattern analysis, fetuses with IVM had altered sulcal positional (both hemispheres) development and combined features of sulcal positional, depth, basin area, in both hemispheres compared to the controls. When comparing distribution of similarity index of individual fetuses, IVM group had shifted toward to lower values compared to the control. About 30 % of fetuses with IVM had no overlap with the distribution of control fetuses. This proof-of-concept study shows that quantitative analysis of fetal MRI can detect emerging subtle neuroanatomical abnormalities in fetuses with IVM and their individual variations.

Abnormal development of transient fetal zones in mild isolated fetal ventriculomegaly

Mild isolated fetal ventriculomegaly (iFVM) is the most common abnormality of the fetal central nervous system. It is characterized by enlargement of one or both of the lateral ventricles (defined as ventricular width greater than 10 mm, but less than 12 mm). Despite its high prevalence, the pathophysiology of iFVM during fetal brain development and the neurobiological substrate beyond ventricular enlargement remain unexplored. In this work, we aimed to establish the relationships between the structural development of transient fetal brain zones/compartments and increased cerebrospinal fluid volume. For this purpose, we used in vivo structural T2-weighted magnetic resonance imaging of 89 fetuses (48 controls and 41 cases with iFVM). Our results indicate abnormal development of transient zones/compartments belonging to both hemispheres (i.e. on the side with and also on the contralateral side without a dilated ventricle) in fetuses with iFVM. Specifically, compared to controls, we observed enlargement of proliferative zones and overgrowth of the cortical plate in iFVM with associated reduction of volumes of central structures, subplate, and fetal white matter. These results indicate that enlarged lateral ventricles might be linked to the development of transient fetal zones and that global brain development should be taken into consideration when evaluating iFVM.

Fetal Ultrasound and Magnetic Resonance Imaging Abnormalities in Congenital Cytomegalovirus Infection Associated with and without Fetal Growth Restriction

Congenital cytomegalovirus infection (cCMV) can cause fetal growth restriction (FGR) and severe sequelae in affected infants. Clinicians generally suspect cCMV based on multiple ultrasound (US) findings associated with cCMV. However, no studies have assessed the diagnostic accuracy of fetal US for cCMV-associated abnormalities in FGR. Eight FGR and 10 non-FGR fetuses prenatally diagnosed with cCMV were examined by undergoing periodic detailed US examinations, as well as postnatal physical and imaging examinations. The diagnostic accuracy of prenatal US for cCMV-associated abnormalities was compared between FGR and non-FGR fetuses with cCMV. The diagnostic sensitivity rates of fetal US for cCMV-related abnormalities in FGR vs. non-FGR fetuses were as follows: ventriculomegaly, 66.7% vs. 88.9%; intracranial calcification, 20.0% vs. 20.0%; cysts and pseudocysts in the brain, 0% vs. 0%; ascites, 100.0% vs. 100.0%; hepatomegaly, 40.0% vs. 100.0%; splenomegaly, 0% vs. 0%. The diagnostic sensitivity of fetal US for hepatomegaly and ventriculomegaly in FGR fetuses with cCMV was lower than that in non-FGR fetuses with cCMV. The prevalence of severe long-term sequelae (e.g., bilateral hearing impairment, epilepsy, cerebral palsy, and severe developmental delay) in the CMV-infected fetuses with FGR was higher, albeit non-significantly. Clinicians should keep in mind the possibility of overlooking the symptoms of cCMV in assessing fetuses with FGR.

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.

Prenatal findings and associated survival rates in fetal ventriculomegaly: A prospective observational study

OBJECTIVES

Fetal ventriculomegaly is associated with varying degrees of genetic and structural abnormalities. The objective was to present the experience of fetal ventriculomegaly in a large European center in relation to: 1. grade of ventriculomegaly; 2. additional chromosomal/structural abnormalities; and 3. perinatal survival rates.

METHODS

This was a prospective observational study of patients referred with fetal ventriculomegaly from January 2011 to July 2020. Data were obtained from the hospital database and analyzed to determine the rate of isolated ventriculomegaly, associated structural abnormalities, chromosomal/genetic abnormalities, and survival rates. Data were stratified into three groups; mild (Vp = 10-12 mm), moderate (Vp = 13-15 mm) and severe (Vp > 15 mm) ventriculomegaly.

RESULTS

There were 213 fetuses included for analysis. Of these 42.7% had mild ventriculomegaly, 44.6% severe and 12.7% had moderate ventriculomegaly. Initial ultrasound assessment reported isolated ventriculomegaly in 45.5% fetuses, with additional structural abnormalities in 54.5%. The rate of chromosomal/genetic abnormalities was high,16.4%. After all investigations, the true rate of isolated VM was 36.1%. The overall survival was 85.6%. Survival was higher for those with isolated VM across all groups (P < 0.05).

CONCLUSION

Ventriculomegaly is a complex condition and patients should be counselled that even with apparently isolated VM, there remains the possibility of additional genetic and/or structural problems being diagnosed in up to 10% of fetuses.

Assessment of foetal ventriculomegaly from prenatal to early postnatal period: a single-centre retrospective cohort study

The aim of this study was to evaluate the early neonatal outcomes of cases with foetal ventriculomegaly (VM) and to investigate the aetiological and prognostic factors according to the degree of VM in a single tertiary referring centre. The medical records of 87 foetuses diagnosed with VM (≥10 mm) within 6 years were evaluated. Postnatal evaluation and early neonatal prognosis were determined in 39 cases divided into two groups as mild (10-15 mm, 30 cases) and severe (>15 mm, 9 cases) according to the ventricular size. The mean gestational age at which foetal VM was detected was 22 + 3 weeks. In terms of severity, severe cases of VM were more frequent in terminated pregnancies. There was no difference in gestational age, birth weight, fifth minute Apgar scores, or cord blood gases between mild and severe cases at delivery. Isolated VM was detected in 63% of mild and 22% of severe cases. In severe cases, the need for intensive care and surgery was higher than in mild cases. Antenatal VM regressed in 50% of mild cases and 22% of severe cases. Increasing knowledge about neonatal prognosis, the factors involved in aetiology, and the degree of VM will guide the management of foetal VM.IMPACT STATEMENTWhat is already known in this subject? Some cases of foetal VM resolve spontaneously, and postnatal ultrasonography can detect normal ventricle sizes. While 74.6% of isolated VM cases show spontaneous regression, this rate is 52.1% in nonisolated cases. The gestational week at the time of diagnosis, the degree and cause of VM, intrauterine progression and the presence of any genetic, infectious, cerebral, or extracerebral disorders all influence the prognosis.What do the results of this study add? Antenatal VM regressed in 50% of mild cases and 22% of severe cases. In severe cases, the need for intensive care and surgery was higher than in mild cases. The higher frequency of accompanying cerebral findings in severe cases was striking.What are the implications of these findings for clinical practice and/or further research? The current study revealed that isolated VM with ventricular diameter less than 15 mm, after excluding out chromosomal abnormalities and prenatal infections, and no prior history of VM, has a favourable neonatal prognosis in terms of mortality and morbidity. In cases of foetal VM, increased knowledge of neonatal prognosis will guide pregnancy care and postnatal follow-up planning. Prospective multicentre studies on the neonatal period are required to bridge the gap between foetal VM and long-term consequences.

Incidence, follow-up, and postnatal clinical progress of children with central nervous system anomalies on fetal MRI

OBJECTIVE

MRI is increasingly employed to assess intrauterine fetal anomalies. Central nervous system (CNS) anomalies are common structural conditions that warrant evaluation with fetal MRI and subsequent prenatal consultation with a pediatric neurosurgeon. As the use of fetal MRI increases, there is greater impetus to understand the most common CNS structural anomalies diagnosed in utero, as well as their natural histories.

METHODS

The authors performed a single-center retrospective review of fetal MRI evaluations performed between January 2012 and December 2020. Children who underwent both prenatal and postnatal neurosurgical evaluations of CNS anomalies were included. Specific CNS anomalies on fetal MRI, associated extra-CNS findings, and suspicion for genetic abnormality or syndromes were noted. Postnatal clinical status and interventions were assessed.

RESULTS

Between January 2012 and December 2020, a total of 469 fetal MRI evaluations were performed; of these, 114 maternal-fetal pairs had CNS anomalies that warranted prenatal consultation and postnatal pediatric neurosurgical follow-up. This cohort included 67 male infants (59%), with a mean ± SD follow-up of 29.8 ± 25.0 months after birth. Fetal MRI was performed at 27.3 ± 5.8 weeks of gestational age. The most frequently reported CNS abnormalities were ventriculomegaly (57%), agenesis or thinning of the corpus callosum (33%), Dandy-Walker complex (DWC) (21%), neuronal migration disorders (18%), and abnormalities of the septum pellucidum (17%). Twenty-one children (18%) required neurosurgical intervention at a mean age of 2.4 ± 3.7 months. The most common surgical conditions included myelomeningocele, moderate to severe ventriculomegaly, encephalocele, and arachnoid cyst. Corpus callosum agenesis or thinning was associated with developmental delay (p = 0.02) and systemic anomalies (p = 0.05). The majority of prenatal patients referred for DWC had Dandy-Walker variants that did not require surgical intervention.

CONCLUSIONS

The most common conditions for prenatal neurosurgical assessment were ventriculomegaly, corpus callosum anomaly, and DWC, whereas the most common surgical conditions were myelomeningocele, hydrocephalus, and arachnoid cyst. Only 18% of prenatal neurosurgical consultations resulted in surgical intervention during infancy. The majority of referrals for prenatal mild ventriculomegaly and DWC were not associated with developmental or surgical sequelae. Patients with corpus callosum abnormalities should be concurrently referred to a neurologist for developmental assessments.

Fetal periventricular pseudocysts: is MRI evaluation needed? What is the long-term neurodevelopmental outcome? Systematic review and meta-analysis

OBJECTIVE

To explore the value of magnetic resonance imaging (MRI) in fetuses with periventricular pseudocysts (PVPC) and the neurodevelopmental outcomes of these fetuses via meta-analysis.

METHODS

MEDLINE and EMBASE database were searched for studies reporting on the MRI assessment of fetuses diagnosed with PVPC on neurosonography. The neurosonography was conducted according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) guidelines or standard axial, coronal and sagittal planes for advanced central nervous system (CNS) assessment. Single-shot fast spin-echo T2-weighted sequences of MRI technique in three orthogonal planes were necessarily performed. The pooled proportion of CNS anomalies missed on neurosonography and detected only at prenatal MRI was calculated. Subanalysis was performed according to the types of intracranial anomalies. The pregnancy outcomes (including normal, abnormal, termination of pregnancy, and perinatal death) of PVPC fetuses were also analyzed.

RESULTS

Five studies comprising 136 fetuses were included in this meta-analysis. Mean gestational age was 29.8 weeks (16-38 weeks) at ultrasonography and 31.5 weeks (25-37 weeks) at MRI. Overall, MRI detected exclusively CNS anomalies in 25.2% (95% CI 15.9-35.8%) of cases. Among them, the highest incidence was white matter abnormalities with the pooled proportion of 16.3% (95% CI 9.7-24.2%). When getting rid of white matter abnormalities, the risk of associated CNS anomalies only detected on MRI was reduced to 9.1% (95% CI 1.8-21.4%). Meanwhile, 130 cases were studied to assess the pregnancy outcomes with the scope of 1 month to 10 years. The pooled proportion of normal outcomes in isolated PVPC fetuses was as high as 95.0% (95% CI 83.9-99.8%). When analyzing the neurodevelopmental outcomes in non-isolated PVPC fetuses, the incidence of normal neurodevelopmental outcomes was about 22.1% (95% CI 5.6-45.5%) with mild and single additional abnormalities, the rate of abnormal neurodevelopmental outcomes was 19.5% (95% CI 11.0-29.7%) with apparent and/or multiple abnormalities. Besides, 53.6% (95% CI 35.4-71.3%) of non-isolated PVPC cases were terminated mainly due to infections, genetic anomalies, metabolic disorders and hemorrhage.

CONCLUSIONS

MRI assessment of PVPC fetuses is recommended to detect associated intracranial anomalies that may be missed on dedicated neurosonography. White matter abnormalities on MRI account for the majority of additional anomalies, which might to be the clue of CMV infection, aminoacidopathy or white matter disease. Moreover, the neurodevelopmental outcome of isolated PVPC fetuses remains favorable, while the neurodevelopmental outcomes of non-isolated PVPC fetuses depend on the accompanying anomaly.

Value of pre- and postnatal magnetic resonance imaging in the evaluation of congenital central nervous system anomalies

Fetal MRI and neonatal MRI of the central nervous system (CNS) are complementary tools that can help to accurately counsel and direct the management of children with anomalies of the central nervous system. Postnatal MRI can add to fetal MRI by allowing for monitoring of changes in the severity of disease, better delineation of a suspected prenatal anomaly, evaluation for secondary pathologies related to the primary diagnosis, and surgical management direction. In this review we discuss the roles of fetal and neonatal MRI in the diagnosis and treatment of congenital anomalies of the CNS through a series of case examples and how both are important in patient management.

Severe fetal ventriculomegaly: Fetal morbidity and mortality, caesarean delivery rates and obstetrical challenges in a large prospective cohort

INTRODUCTION

Severe fetal ventriculomegaly (VM) is defined as an enlargement of the atria of the lateral cerebral ventricles (Vp) of greater than 15 mm. While it is well established that it confers significant risk of morbidity and mortality to the neonate, there is limited information pertaining to the caesarean delivery rates and the obstetric management of these complex cases. The aim of this study was twofold: firstly, to determine survival rates in fetuses with severe VM, and secondly to determine the caesarean delivery rates in continuing pregnancies. We explore the obstetric challenges associated with these difficult cases.

METHODS

This was a prospective observational study of patients with antenatal severe VM, attending the Department of Fetal Medicine, National Maternity Hospital, Dublin, Ireland, from 1st January 2011 to 31st July 2020. Data were obtained from the hospital database and those with severe VM (Vp > 15 mm) were identified. The rates of chromosomal abnormalities, the survival rates and the caesarean delivery (CD) rates for the overall group were then determined. The data were then further sub-divided into two groups: 1. Vp < 20 mm and 2. Vp > 20 mm, and the results compared. Statistical analysis was performed using the Chi-Square test.

RESULTS

A total of N = 95 pregnancies with severe VM were included for analysis, of which additional structural abnormalities on ultrasound were apparent in 67/95 (70.5%) and 28/95 (29.5%) had isolated severe VM. Chromosomal abnormalities were diagnosed in 15/95 (15.8%) of cases, with (2/28) 7.1% in the isolated SVM group versus (13/67) 19.4% in the non-isolated SVM group. The overall survival rate (excluding TOP) was 53/74 (71.6%), with 20/23 (86.9%) in the isolated SVM group. The overall CD rate was 47/72 (65.3%), which was significantly higher than the CD for the hospital during the same time period of 25.4% (P < 0.01). The data were subdivided into Vp < 20 and Vp > 20 and those with a Vp > 20 had higher rates of additional intracranial findings on ultrasound (Vp < 20 13/41 (31.7%) versus Vp > 20 32/54 (59.3%) (P < 0.05)) and macrocrania (Vp < 20 14/41 (34.1%) versus Vp > 20 35/54 (64.8%) (P < 0.05)). No significant difference was observed in the overall survival or CD rates between the two groups.

CONCLUSION

In conclusion this study reports significant fetal morbidity and mortality with severe VM with high CD rates observed in this cohort. Significant challenges exist in relation to the obstetric management and counseling of parents regarding an often uncertain neonatal prognosis. In continuing pregnancies with significant macrocrania delivery plans should be individualized to improve neonatal outcomes where possible and minimize harm to the mother.

Neurological and clinical outcomes in infants and children with a fetal diagnosis of asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum

OBJECTIVE

Advances in prenatal imaging have facilitated improvements in the fetal diagnosis of congenital anomalies. Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID) is a constellation of congenital anomalies reported in fetal imaging. However, few data are available regarding postnatal outcomes of infants and children with a fetal diagnosis of AVID. The authors sought to report the neurodevelopmental outcomes of patients diagnosed with AVID before birth at a single institution.

METHODS

An institutional fetal imaging database was queried to identify cases with ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum over a 10-year study period from 2000 to 2019. Overall, 41 maternal-infant dyads who met imaging criteria for AVID were identified; medical records were reviewed for prenatal variables including gestational age at birth, perinatal complications including fetal demise, and postnatal variables including demographics, mortality, hydrocephalus diagnosis and management, epilepsy, and neurodevelopmental outcomes at 2 years or the last follow-up.

RESULTS

Among 41 patients, 25 (61%) were male. A slight majority of patients (55%) were born before 36 weeks of gestational age, and 27 patients (68%) were delivered via cesarean section because their head size precluded vaginal delivery. There were 8 incidences of fetal demise, 1 pregnancy was terminated, and 32 patients were born alive. Neonatal or early infant death occurred in 5 patients. Two children died during follow-up after the neonatal period (ages 7 months and 7 years). Twenty-six children survived to at least the 2-year follow-up, all of whom required treatment for hydrocephalus. Of those 26 children, 12 (46%) had a diagnosis of epilepsy, 14 (54%) could sit independently, 4 (16%) were in mainstream school, 16 (62%) had expressive language, and 7 (28%) had near-normal development without seizures.

CONCLUSIONS

Among 41 maternal-fetal dyads with AVID, a majority of children survived to the 2-year follow-up, although all developed hydrocephalus. Many continued to have seizures, but expressive language use, attendance at mainstream school, and near-normal development without seizures were not infrequent. These data are critical for prenatal counseling and to establish the natural history of a diagnosis with limited outcome data.

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.

Prenatal Ventriculomegaly - Diagnosis, Prognostication and Management

Fetal ventriculomegaly (VM) refers to the abnormal enlargement of one or more ventricles of the brain in-utero. The enlargement may or may not be related to ventricular obstruction and increased intracranial pressure; therefore, the term "hydrocephalus" is not used. VM is diagnosed usually in the mid-trimester when the atrial diameter (AD) of the lateral ventricle is more than 10 mm on one or both sides. A thorough workup is then required to identify the cause as the etiology is diverse. Fetal magnetic resonance imaging (MRI) may yield additional information. Serial ultrasound follow-up would be required to assess its progression with advancing gestation. The prognosis and long-term outcomes greatly depend upon the etiology, the severity at diagnosis, progression, and associations. This article reviews the definitions, diagnosis, and workup of fetal VM, discusses follow-up protocols and prognosis, and examines the role of fetal therapy, including fetoscopic surgery in its prenatal management.

Chromosomal microarray analysis vs. karyotyping for fetal ventriculomegaly: a meta-analysis

BACKGROUND

Chromosomal abnormalities are important causes of ventriculomegaly (VM). In mild and isolated cases of fetal VM, obstetricians rarely give clear indications for pregnancy termination. We aimed to calculate the incidence of chromosomal abnormalities and incremental yield of chromosomal microarray analysis (CMA) in VM, providing more information on genetic counseling and prognostic evaluation for fetuses with VM.

METHODS

The Chinese language databases Wanfang Data, China National Knowledge Infrastructure, and China Biomedical Literature Database (from January 1, 1991 to April 29, 2020) and English language databases PubMed, Embase, and Cochrane Library (from January 1, 1945 to April 29, 2020) were systematically searched for articles on fetal VM. Diagnostic criteria were based on ultrasonographic or magnetic resonance imaging (MRI) assessment of lateral ventricular atrium width: ≥10 to <15 mm for mild VM, and ≥15 mm for severe VM. Isolated VM was defined by the absence of structural abnormalities other than VM detected by ultrasonography or MRI. R software was used for the meta-analysis to determine the incidence of chromosomal abnormalities and incremental yield of CMA in VM, and the combined rate and 95% confidence interval (CI) were calculated.

RESULTS

Twenty-three articles involving 1635 patients were included. The incidence of chromosomal abnormalities in VM was 9% (95% CI: 5%-12%) and incremental yield of CMA in VM was 11% (95% CI: 7%-16%). The incidences of chromosomal abnormalities in mild, severe, isolated, and non-isolated VM were 9% (95% CI: 4%-16%), 5% (95% CI: 1%-11%), 3% (95% CI: 1%-6%), and 13% (95% CI: 4%-25%), respectively.

CONCLUSIONS

Applying CMA in VM improved the detection rate of abnormalities. When VM is confirmed by ultrasound or MRI, obstetricians should recommend fetal karyotype analysis to exclude chromosomal abnormalities. Moreover, CMA should be recommended preferentially in pregnant women with fetal VM who are undergoing invasive prenatal diagnosis. CMA cannot completely replace chromosome karyotype analysis.

Perinatal post-mortem magnetic resonance imaging (MRI) of the central nervous system (CNS): a pictorial review

Central nervous system (CNS) abnormalities cause approximately 32–37.7% of terminations of pregnancy (TOP). Autopsy is currently the gold standard for assessing dead foetuses and stillborn. However, it has limitations and is sometimes subject to parental rejection. Recent studies have described post-mortem foetal magnetic resonance imaging (MRI) as an alternative and even complementary to autopsy for CNS assessment. Radiologists now play a key role in the evaluation of perinatal deaths. Assessment of foetal CNS abnormalities is difficult, and interpretation of foetal studies requires familiarisation with normal and abnormal findings in post-mortem MRI studies as well as the strengths and limitations of the imaging studies. The purpose of this pictorial review is to report our experience in the post-mortem MRI evaluation of the CNS system, including a description of the protocol used, normal CNS findings related to post-mortem status, abnormal CNS findings in our sample, and the correlation of these findings with histopathological results.

Neurodevelopmental outcomes in mild and moderate isolated ventriculomegaly originating in utero

OBJECTIVE

To determine the differences in outcomes between mild and moderate isolated ventriculomegaly (IVM).

METHODS

We conducted a prospective cohort study on 94 fetuses with IVM and evaluated the neurodevelopmental outcomes at 12 months of age using the ASQ-3 and BSID-I neurodevelopmental assessment tools. Progression of VM was defined as an increase in the width of the ventricular by at least 3 mm during sequential ultrasound monitoring. The population was divided into two groups according to ventricular width: mild (10-12 mm) and moderate (12.1-15 mm), which were further evaluated for VM progression in utero separately.

RESULTS

Neurodevelopmental assessments at 12 months were the main form of evaluations. Neurodevelopmental impairment (NDI) was defined as a mental development index (MDI) or psychomotor development index (PDI) < 85. There were no significant differences in NDI values between the mild and moderate groups (p = .155). Compared with the non-in utero progression group (7.6%), the rate of NDI was significantly higher (p = .004) in the group with progression (33.3%). Using linear regression and correlation, no negative correlation was found between the maximum value of atrial diameter (AD) in utero and the PDI (r = -0.021, p = .914) or MDI (r = -0.073, p = .703) score. However, the maximum change in the AD in utero was negatively correlated with both PDI (r = -0.460, p = .011) and MDI (r=-0.422, p = .020) scores.

CONCLUSION

There were likely no differences in neurodevelopmental outcomes between mild and moderate IVM. In fetuses with mild to moderate VM, intrauterine progression may be a poor prognostic factor for neurodevelopmental outcomes.

The value of prenatal magnetic resonance imaging and postnatal follow-up using Gesell Developmental Schedules score for mild-to-moderate simple bilateral fetal ventriculomegaly

OBJECTIVE

To investigate the relationship of mild-to-moderate simple bilateral fetal ventriculomegaly with postnatal neurological development.

METHODS

Cases of simple lateral ventricular dilatation (273) were divided into bilateral mild dilatation (10.0-12.0 mm, 62), bilateral moderate dilatation (12.1-15.0 mm, 29), unilateral mild dilatation (133), and unilateral moderate dilatation (49) groups. The control group comprised 50 normal fetuses. Neurological development was assessed using Gesell Developmental Schedules (GDS) at postnatal 3, 6, 12, and 18 months.

RESULTS

At postnatal 6, 12, and 18 months, the GDS score was higher for bilateral than for unilateral dilatation (p < .05). At postnatal 3 and 6 months, the GDS score was higher for the bilateral dilatation groups than for the control group (p < .05). At postnatal 6, 12, and 18 months, the GDS score was higher for the bilateral moderate dilatation group than for the unilateral moderate dilatation group (p < .05). Further, at postnatal 3, 6, 12, and 18 months, the GDS score was higher for the bilateral moderate dilatation group than for the control group (p < .05).

CONCLUSION

At postnatal month 6, the GDS evaluation results of the bilateral dilatation groups were significantly inferior compared to those of the unilateral dilatation group.

Prenatal ventriculomegaly: natural course, survival, and neurodevelopmental status

OBJECTIVE

Prenatal ventriculomegaly is classified as mild, moderate, or severe based on the atrium diameter. The natural course and intrauterine progression of mild and moderate ventriculomegaly associated with the neurodevelopmental status of these children has been widely reported.

METHODS

One hundred twenty-two pregnancies with mild and moderate ventriculomegaly referred to the pediatric neurosurgery clinic of Children's Medical Center between 2010 and 2018 were retrospectively studied. The authors collected demographic and first and sequential ultrasonographic information, associated abnormalities, information about pregnancy outcomes, and the latest developmental status of these children according to Centers for Disease Control and Prevention criteria by calling parents at least 1 year after birth.

RESULTS

The mean gestational age at the time of diagnosis was 29.1 weeks, and 53% of fetuses were female. The width of the atrium was registered precisely in 106 cases, in which 61% had mild and 39% had moderate ventriculomegaly. Information on serial ultrasound scans was collected in 84 cases in which ventriculomegaly regressed in 5, remained stable in 67, and progressed in 12 patients. Fourteen cases (29.7%) in the mild ventriculomegaly group and 6 cases (16.2%) in the moderate group had associated abnormalities, with corpus callosum agenesis as the most frequent abnormality. The survival rate was 80% in mild and 89.4% in moderate ventriculomegaly. Considering survival to live birth and progression of the ventriculomegaly, the survival rate was 100% in regressed, 97% in stable, and 41.6% in progressed ventricular width groups (p < 0.001). Neurodevelopmental status was evaluated in 73 cases and found to be normal in 69.8% of the cases; 16.4% of children had mild delay, and 5.4% and 8.2% of cases were diagnosed with moderate and severe delays, respectively.

CONCLUSIONS

In spite of a high rate of missed data in our retrospective study, most patients with mild or moderate ventriculomegaly had a stable or regressed course. Most cases had near-normal developmental status. Prospective studies with a larger sample size and detailed developmental evaluation tests are needed to answer the questions related to the natural course, survival, and prognosis of prenatal ventriculomegaly.

Immunoglobulin fetal therapy and neonatal therapy with antiviral drugs improve neurological outcome of infants with symptomatic congenital cytomegalovirus infection

Infants with symptomatic congenital cytomegalovirus infection (cCMV) suffer from long-term sequelae. This study aimed at evaluating the efficacy of combining immunoglobulin (Ig) fetal therapy (FT) and neonatal therapy (NT) with antiviral drugs to improve neurological outcomes of affected infants. Women whose fetuses had symptomatic cCMV received Ig injection into the fetal peritoneal cavity and/or maternal blood as FT, while affected newborns received oral valganciclovir or intravenous ganciclovir as NT. We compared the neurological outcomes at ≥18 months old between infants receiving FT with or without NT (FT group) and those receiving NT only (NT group). From 2009-2019, 15 women whose fetuses had symptomatic cCMV received FT, while 19 newborns received NT only. In FT group, two newborns died, and two were <18 months old. Neurological outcomes of the remaining 11 infants in FT group were as follows: normal 45.5 %, mild impairments 36.4 %, and severe impairments 18.2 %. In NT group, one newborn died, one's parents refused the follow-up, one was <18 months old, and two had only chorioretinitis as symptoms. Neurological outcomes of the remaining 14 infants in NT group were as follows: normal 21.4 %, mild impairments 14.3 %, and severe impairments 64.3 %. The proportion of infants with severe impairments in FT group was significantly lower than that in NT group (18.2 % vs 64.3 %, p < 0.05). This is the first trial demonstrating that the combination of Ig FT and NT with antiviral drugs may be more effective in improving neurological outcomes of newborns with symptomatic cCMV as compared to NT only.

MRI in the diagnosis of fetal developmental brain abnormalities: the MERIDIAN diagnostic accuracy study

BACKGROUND

Ultrasonography has been the mainstay of antenatal screening programmes in the UK for many years. Technical factors and physical limitations may result in suboptimal images that can lead to incorrect diagnoses and inaccurate counselling and prognostic information being given to parents. Previous studies suggest that the addition of in utero magnetic resonance imaging (iuMRI) may improve diagnostic accuracy for fetal brain abnormalities. These studies have limitations, including a lack of an outcome reference diagnosis (ORD), which means that improvements could not be assessed accurately.

OBJECTIVES

To assess the diagnostic impact, acceptability and cost consequence of iuMRI among fetuses with a suspected fetal brain abnormality.

DESIGN

A pragmatic, prospective, multicentre, cohort study with a health economics analysis and a sociological substudy.

SETTING

Sixteen UK fetal medicine centres.

PARTICIPANTS

Pregnant women aged ≥ 16 years carrying a fetus (at least 18 weeks' gestation) with a suspected brain abnormality detected on ultrasonography.

INTERVENTIONS

Participants underwent iuMRI and the findings were reported to their referring fetal medicine clinician.

MAIN OUTCOME MEASURES

Pregnancy outcome was followed up and an ORD from postnatal imaging or postmortem autopsy/imaging collected when available. Developmental data from the Bayley Scales of Infant Development and questionnaires were collected from the surviving infants aged 2-3 years. Data on the management of the pregnancy before and after the iuMRI were collected to inform the economic evaluation. Two surveys collected data on patient acceptability of iuMRI and qualitative interviews with participants and health professionals were undertaken.

RESULTS

The primary analysis consisted of 570 fetuses. The absolute diagnostic accuracies of ultrasonography and iuMRI were 68% and 93%, respectively [a difference of 25%, 95% confidence interval (CI) 21% to 29%]. The difference between ultrasonography and iuMRI increased with gestational age. In the 18-23 weeks group, the figures were 70% for ultrasonography and 92% for iuMRI (difference of 23%, 95% CI 18% to 27%); in the ≥ 24 weeks group, the figures were 65% for ultrasonography and 94% for iuMRI (difference of 29%, 95% CI 23% to 36%). Patient acceptability was high, with at least 95% of respondents stating that they would have iuMRI again in a similar situation. Health professional interviews suggested that iuMRI was acceptable to clinicians and that iuMRI was useful as an adjunct to ultrasonography, but not as a replacement. Across a range of scenarios, iuMRI resulted in additional costs compared with ultrasonography alone. The additional cost was consistently < £600 per patient and the cost per management decision appropriately changed was always < £3000. There is potential for reporting bias from the referring clinicians on the diagnostic and prognostic outcomes. Lower than anticipated follow-up rates at 3 years of age were observed.

CONCLUSIONS

iuMRI as an adjunct to ultrasonography significantly improves the diagnostic accuracy and confidence for the detection of fetal brain abnormalities. An evaluation of the use of iuMRI for cases of isolated microcephaly and the diagnosis of fetal spine abnormalities is recommended. Longer-term follow-up studies of children diagnosed with fetal brain abnormalities are required to fully assess the functional significance of the diagnoses.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN27626961.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 49. See the NIHR Journals Library website for further project information.

Global and Regional Changes in Cortical Development Assessed by MRI in Fetuses with Isolated Nonsevere Ventriculomegaly Correlate with Neonatal Neurobehavior

BACKGROUND AND PURPOSE

Fetuses with isolated nonsevere ventriculomegaly (INSVM) are at risk of presenting neurodevelopmental delay. However, the currently used clinical parameters are insufficient to select cases with high risk and determine whether subtle changes in brain development are present and might be a risk factor. The aim of this study was to perform a comprehensive evaluation of cortical development in INSVM by magnetic resonance (MR) imaging and assess its association with neonatal neurobehavior.

MATERIALS AND METHODS

Thirty-two INSVM fetuses and 29 healthy controls between 26-28 weeks of gestation were evaluated using MR imaging. We compared sulci and fissure depth, cortical maturation grading of specific areas and sulci and volumes of different brain regions obtained from 3D brain reconstruction of cases and controls. Neonatal outcome was assessed by using the Neonatal Behavioral Assessment Scale at a mean of 4 ± 2 weeks after birth.

RESULTS

Fetuses with INSVM showed less profound and underdeveloped sulcation, including the Sylvian fissure (mean depth: controls 16.8 ± 1.9 mm, versus INSVM 16.0 ± 1.6 mm; P = .01), and reduced global cortical grading (mean score: controls 42.9 ± 10.2 mm, versus INSVM: 37.8 ± 9.9 mm; P = .01). Fetuses with isolated nonsevere ventriculomegaly showed a mean global increase of gray matter volume (controls, 276.8 ± 46.0 ×10 mm³, versus INSVM 277.5 ± 49.3 ×10 mm³, P = .01), but decreased mean cortical volume in the frontal lobe (left: controls, 53.2 ± 8.8 ×10 mm³, versus INSVM 52.4 ± 5.4 ×10 mm³; P = < .01). Sulcal depth and brain volumes were significantly associated with the Neonatal Behavioral Assessment Scale severity (P = .005, Nagelkerke R² = 0.732).

CONCLUSIONS

INSVM fetuses showed differences in cortical development, including regions far from the lateral ventricles, that are associated with neonatal neurobehavior. These results suggest the possible use of these parameters to identify cases at higher risk of altered neurodevelopment.

Brain abnormalities on neuroimaging in Children with Congenital Zika Syndrome in Salvador, Brazil, and its possible implications on neuropsychological development

OBJECTIVE

To characterize the spectrum of brain damages presented in children affected by Congenital Zika Syndrome (CZS), verify the existence of a co-occurrence pattern of these damages and discuss possible implications for the neuropsychological development.

METHODS

Descriptive, quantitative, individualized, and cross-sectional study using secondary sources. We selected 136 children with CZS from the database of the Center of Strategic Information on Health Vigilance of the Municipal Office of Salvador, Brazil. We conducted descriptive and multiple correspondence analyses.

RESULTS

Among the set of analyzed variables, microcephaly (51.5%), ventriculomegaly (57.4%), and brain calcifications (77.2%) were identified as the most frequent. The multiple correspondence analysis showed that the combination of these three variables (32.4%) was what better represented the spectrum of brain damages in the Central Nervous System.

INTERPRETATION

Damage in the sensory-motor, cognitive and language development, as well as neurodevelopmental disorders, are described in the literature as impairments associated, either isolated or combined, with these damages, and it is worth highlighting that, in combined brain damages, impairments tend to be more severe. The findings of this study may contribute to understanding the repercussions of CZS on the neuropsychological development of children affected by the epidemic.

Fetal Neuroimaging Update

OBJECTIVES

To review the current imaging techniques available for the evaluation of the fetal brain.

FINDINGS

Ultrasound remains the initial screening modality with routine scanning typically performed at 18-20 weeks gestation. When a central nervous system (CNS) abnormality is noted by ultrasound, MRI is increasingly being used to further clarify findings. Fetal MRI has the unique ability to provide high detailed anatomical information of the entire human fetus with high contrast resolution. This technique has grown due to the development of rapid single shot image acquisition sequences, improvement of motion correction strategies and optimizing shimming techniques.

CONCLUSIONS

The assessment of fetal CNS anomalies continues to improve. Advanced MRI techniques have allowed for further delineation of CNS anomalies and have become a cornerstone in the assessment of fetal brain well-being. Those interpreting fetal studies need to be familiar with the strengths and limitations of each exam and be sensitive to the impact discussing findings can have regarding perinatal care and delivery planning. Collaboration with neurologists, neurosurgeons, geneticists, counselors, and maternal fetal specialists are key in providing the best care to the families we treat.

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.

Acceleration and plateau: two patterns and outcomes of isolated severe fetal cerebral ventricular dilation

OBJECTIVES

We sought to characterize patterns of in utero dilation in isolated severe fetal ventriculomegaly (ISVM) and investigate their value in predicting obstetrical and postnatal outcomes.

METHODS

This is a retrospective cohort study. ISVM was defined as a sonographic cerebral ventricle atrial with width ≥15 mm in the absence of additional cerebral or other anatomic anomalies. The aim of this study was to characterize two ISVM groups using a receiver operator curve to evaluate the rate of ventricular progression versus need for ventriculoperitoneal (VP) shunt postnatally. Outcomes were compared between the groups using Pearson's chi-squared test, Student t-test, and descriptive statistics.

RESULTS

Based on the ROC analysis, ventricular growth of ≥3 mm/week versus <3 mm/week distinguished fetuses likely to require a postnatal VP shunt. Fetuses were characterized as accelerators if ventricle growth was ≥3 mm/week at any point and plateaus if <3 mm/week. Accelerators showed a greater average rate of ventricle progression than plateaus (4.1 vs. 1.0 mm/week, respectively, p = .031) and were more likely to be delivered at earlier gestational ages (34.7 vs. 37.1 weeks respectively, p = .02). Ninety percent of accelerators demonstrated a need for shunt placement compared with 18.8% of plateaus (p < .001). Significantly more plateaus (87.5%) underwent a trial of labor while accelerators were more likely to have planned cesareans (70%, p = .009).

CONCLUSIONS

This study characterizes ISVM into two distinct populations based upon the rate of ventricle expansion, differentiated by the need for postnatal shunting. Once a ventricular growth pattern is determined, these distinctions should prove useful in prenatal management and delivery planning.

Epidemiology of fetal cerebral ventriculomegaly and evaluation of chromosomal microarray analysis versus karyotyping for prenatal diagnosis in a Chinese hospital

Objective

To evaluate the efficiency and incremental value of chromosomal microarray analysis as compared with standard karyotyping for the identification of genomic abnormalities in fetal DNA.

Methods

This retrospective study enrolled female patients with ultrasonographically diagnosed fetal ventriculomegaly. The prevalence, associated anomalies and clinical outcomes of ventriculomegaly were evaluated based on data from a single maternal and child health hospital in southwest China.

Results

A total of 943 cases of ventriculomegaly were analysed in this study, which were diagnosed at a mean ± SD gestational age of 23.8 ± 8.2 weeks. Non-isolated ventriculomegaly cases had a significantly higher maternal age than isolated cases (29.6 ± 5.5 versus 27.9 ± 4.2 years, respectively) and were also associated with a larger proportion of bilateral (56.1% versus 46.7%, respectively) and severe (12.8% versus 3.7%, respectively) ventriculomegaly. There were 97 cases detected by both karyotyping and microarray analysis. All apparent chromosome abnormalities identified upon karyotyping were detected with the use of microarray analysis. Microarray analysis also reported genetic abnormalities in 20 additional cases not detected by karyotyping. Of these additional 20 cases, 9.3% of pregnancies reported standard genetic variants for clinically relevant information, whereas 11.3% reported uncertain genetic abnormalities.

Conclusion

Chromosomal microarray analysis is an efficient tool, significantly increasing the diagnostic power for prenatal diagnosis.

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.

Prognosis of fetuses with ventriculomegaly: An observational retrospective study

OBJECTIVE

To investigate the prognosis of fetuses with ventriculomegaly (VM).

METHODS

Clinical data were collected from 234 cases of fetal VM diagnosed by ultrasound between March 2010 and July 2016. VM progression was monitored, and karyotyping and infection screening performed. Magnetic resonance imaging (MRI) was performed where increasing ventricular diameter was noted. Neonatal behavioral neurological assessment (NBNA) was carried out after birth, and Bayley Scales of Infant Development assessment at 6 months.

RESULTS

The in utero outcomes of Group A were better than Group B in 173 pregnancies. Isolated VM (IVM) was associated with better prognosis than nonisolated VM (NIVM); the regression rates were 74.6% (59/79) and 52.1% (49/94), respectively (χ² = 10.222, .006). The NBNA scores were significantly higher in Group A than Group B (χ² = 4.231, .004), but not significantly different between IVM and NIVM. The composition ratios of both the psychomotor and mental developmental index (PDI and MDI) scores were not significantly different between Groups A and B (Z = 1.869, .062 and Z = 0.826, .409, respectively). Significant differences in in utero outcomes were observed between IVM and NIVM cases in Groups A and B.

CONCLUSIONS

Fetal VM prognosis is affected by the width of ventricle, chromosome abnormalities, coexisted abnormalities, and in utero progression.

Fetal aqueductal stenosis: Prenatal diagnosis and intervention

Fetal severe central nervous system ventriculomegaly is associated with poor neurologic outcomes, usually driven by a primary malformation, deformation, or disruption of brain parenchyma. In utero shunting of excess cerebrospinal fluid (CSF) in hopes of improving neurologic outcomes was attempted in the 1980s but was abandoned due to perceived lack of effect, likely due to technological limitations of the time that precluded proper patient selection. Little progress on the antenatal management of severe ventriculomegaly has been made in the intervening decades. A multidisciplinary, evidence-based reassessment of ventriculoamniotic shunting for isolated fetal aqueductal stenosis (FAS), a unique form of severe ventriculomegaly (supratentorial intracranial hypertension), is currently underway. An accurate diagnosis of FAS must precede in utero intervention. Magnetic resonance imaging (MRI) will be an excellent adjunct to high-resolution prenatal ultrasound and next-generation genetic testing to correctly diagnose FAS in a timely fashion while excluding other intracranial and extracranial anomalies. This manuscript will briefly discuss the history, current management, and future directions of the prenatal diagnosis and potential intervention for FAS.

Copy number variations and fetal ventriculomegaly

PURPOSE OF REVIEW

Ventriculomegaly is one of the most common abnormal sonographic findings, which is associated with congenital infection, chromosomal and additional structural abnormalities. Currently, karyotype analysis is the primary method to detect chromosomal abnormalities in fetuses with ventriculomegaly. Recently, with the introduction of chromosomal microarray analysis (CMA) in prenatal diagnosis, copy number variations (CNVs) have been identified in cases of ventriculomegaly. The purpose of this review is to summarize the current knowledge about the genetic cause of fetal ventriculomegaly, with particular attention to primary articles regarding the association between CNVs and fetal ventriculomegaly.

RECENT FINDINGS

Recent studies have disclosed that in addition to numerical chromosomal abnormalities and large chromosomal imbalances, pathogenic CNVs are another important genetic cause of fetal ventriculomegaly, which may be involved in the pathological process of fetal ventriculomegaly as well as postnatal neurodevelopmental disorders. Furthermore, it is reported that the incidences of pathogenic CNVs in fetuses with ventriculomegaly were associated with the presence of other structural anomalies, but were irrelevant to the severity of ventriculomegaly.

SUMMARY

CNVs are an important cause of fetal ventriculomegaly and CMA should be offered to all fetuses with ventriculomegaly, regardless of the degree of ventriculomegaly or whether combined with other structural anomalies.

Altered cortical development in fetuses with isolated nonsevere ventriculomegaly assessed by neurosonography

OBJECTIVES

To perform a comprehensive assessment of cortical development in fetuses with isolated nonsevere ventriculomegaly (INSVM) by neurosonography.

METHODS

We prospectively included 40 fetuses with INSVM and 40 controls. INSVM was defined as atrial width between 10.0 and 14.9 mm without associated malformation, infection, or chromosomal abnormality. Cortical development was assessed by neurosonography at 26 and 30 weeks of gestation measuring depth of selected sulci and applying a maturation scale from 0 (no appearance) to 5 (maximally developed) of main sulci and areas.

RESULTS

INSVM showed underdeveloped calcarine and parieto-occipital sulci. In addition, significant delayed maturation pattern was also observed in regions distant to ventricular system including Insula depth (controls 30.8 mm [SD 1.7] vs INSVM 31.7 mm [1.8]; P = .04), Sylvian fissure grading (>2 at 26 weeks: controls 87.5% vs INSVM 50%, P = .01), mesial area grading (>2 at 30 weeks: controls 95% vs INSVM 62.5%; P = .03), and cingulate sulcus grading (>2 at 30 weeks: controls 100% vs INSVM 80.5%; P = .01).

CONCLUSIONS

Fetuses with INSVM showed underdeveloped cortical maturation including also regions, where effect of ventricular dilatation is unlikely. These results suggest that in a proportion of fetuses with INSVM, ventricular dilation might be related with altered cortical architecture.

Clinical value of prenatal MRI for diagnosis of isolated ventriculomegaly and prediction of early postnatal developmental outcomes

OBJECTIVE

To investigate the relationship of ventriculomegaly (VM) with postnatal neurological development.

METHODS

Fetuses with isolated VM on MRI (n = 160; VM group) were separated into three subgroups according to lateral ventricle width: subgroup A (10.0-12.0 mm; n = 113), subgroup B (12.1-15.0 mm; n = 37), and subgroup C (>15.0 mm; n = 10). Fifty normal fetuses formed a control group. Post-delivery changes in ventricular width and neurological development were assessed with MRI/ultrasonography and the Gesell Development Schedules (GDS), respectively, at 3, 6, 12, and 18 months.

RESULTS

GDS scores of subgroup A and subgroup B did not differ from that of the controls at 3 and 6 months. Subgroup B scores differed significantly from the control scores at 12 and 18 months. Subgroup C scores differed from the control scores at all-time points (all P < 0.05). In the VM group, GDS scores at 12 and 18 months were significantly different from the scores at 3 months, and the score at 18 months was significantly different from the score at 6 months (P < 0.05 for all).

CONCLUSION

The milder the VM, the more likely it was to disappear or improve in the postnatal period. However, specific postnatal rehabilitation should be considered when fetal ventricular width is greater than 12.1 mm.

Clinical outcomes following prenatal diagnosis of asymmetric ventriculomegaly, interhemispheric cyst, and callosal dysgenesis (AVID)

OBJECTIVES

When identified prenatally, the imaging triad of asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID) can indicate a more serious congenital brain anomaly. In this follow-up series of 15 fetuses, we present the neurodevelopmental outcomes of a single institution cohort of children diagnosed prenatally with AVID.

METHODS

Our fetal ultrasound database was queried for cases of AVID between 2000 and 2016. All available fetal MR imaging studies were reviewed for the presence of (a) interhemispheric cysts or ventricular diverticula and (b) dysgenesis or agenesis of the corpus callosum. Clinical records were reviewed for perinatal management, postnatal surgical management, and neurodevelopmental outcomes.

RESULTS

Fifteen prenatal cases of AVID were identified. Twelve were live-born and three pregnancies were terminated. Of the 12 patients, 11 underwent neurosurgical intervention. Of the eight patients surviving past infancy, seven of eight have moderate to severe neurodevelopmental delays or disabilities, encompassing both motor and language skills, and all have variable visual abnormalities.

CONCLUSION

In our cohort of 15 prenatally diagnosed fetuses with AVID, eight survived past infancy and all have neurodevelopmental disabilities, including motor and language deficits, a wide range of visual defects, craniofacial abnormalities, and medical comorbidities.

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.

Prenatal aqueduct stenosis: Association with rhombencephalosynapsis and neonatal outcome

BACKGROUND AND PURPOSE

To examine prenatal MRI and postnatal imaging in fetuses with congenital aqueductal stenosis (CAS) to determine the frequency of association of rhombencephalosynapsis (RES) and how it may affect neonatal intensive care unit (NICU) course.

MATERIALS AND METHODS

A single center IRB-approved retrospective study of children with CAS was performed. Prenatal MRI, postnatal images, and clinical data were reviewed. Statistical analysis was performed with SAS statistical software package version 9.3.

RESULTS

Aqueduct obstruction was confirmed for all 30 participants. Hydrocephalus required shunting in all but one (97%). Fifteen neonates had CAS with rhomboencephalosynapsis (RES) (50%). Although neonatal course between the two groups was comparable, 53% of CAS with RES neonates required feeding assistance versus 20% in CAS only (P = 0.128). Shunting in the CAS with RES group occurred at average of 6 days of life versus CAS group at 55 days (P = 0.196). Biometry measurements showed a statistically significant decrease in pons antero-posterior diameter in both groups (CAS only P = 0.0049 and CAS with RES P = 0.0003) when compared with norms for gestational age.

CONCLUSION

CAS has a high association with RES. Feeding assistance in the NICU and earlier neurosurgical intervention may be required in patients with CAS who also have RES.

Outcome of Isolated Absent Septum Pellucidum Diagnosed by Fetal Magnetic Resonance Imaging (MRI) Scan

Improved fetal imaging has resulted in increased diagnosis of isolated absent septum pellucidum without other intracranial abnormalities. There is little literature regarding outcomes for these fetuses. This study hypothesized the majority of infants diagnosed by fetal magnetic resonance imaging (MRI) with isolated absent septum pellucidum would retain this diagnosis postnatally. Specifically, in the absence of postnatal endocrine or ophthalmologic abnormalities, postnatal imaging would find no additional related findings, and fetuses would be at low risk for developmental delay. Two of 8 subjects met postnatal criteria for septo-optic dysplasia; remaining subjects had normal postnatal endocrine and ophthalmologic evaluations and no significant related findings on postnatal MRI. One subject without septo-optic dysplasia had delays on developmental screening; all others had normal screening (range of follow-up 8-72 months). Our study questions the necessity of postnatal imaging for prenatally diagnosed isolated absent septum pellucidum. Majority of fetuses with isolated absent septum pellucidum retained this diagnosis postnatally.

Genomic detection of a familial 382 Kb 6q27 deletion in a fetus with isolated severe ventriculomegaly and her affected mother

Terminal deletions of the chromosome 6q27 region are rare genomic abnormalities, linked to specific brain malformations and other neurological phenotypes. Reported cases have variable sized genomic deletions that harbor several genes including the DLL1 and TBP. We report on an inherited 0.38 Mb terminal deletion of chromosome 6q27 in a 22-week fetus with isolated bilateral ventriculomegaly and her affected mother using microarray-based comparative genomic hybridization and fluorescent in situ hybridization (FISH). The deleted region harbors at least seven genes including DLL1 and TBP. The affected mother had a history of hydrocephalus, developmental delay, and seizures commonly associated with DLL1 and TBP 6q27 deletions. This deletion is one of the smallest reported isolated 6q27 terminal deletions. Our data provides additional evidence that haploinsufficiency of the DLL1 and TBP genes may be sufficient to cause the ventriculomegaly, seizures, and developmental delays associated with terminal 6q27 deletions, indicating a plausible role in the abnormal development of the central nervous system.

Evaluation of choroid plexus with fetal magnetic resonance imaging: What happens in ventriculomegaly?

OBJECTIVES

Diagnosis of ventriculomegaly (VM) and identification of choroid plexus (CP) can be challenging with fetal magnetic resonance imaging (MRI). Our aim is to create an adjunct method for supporting the diagnosis of VM by investigating the CP-ventricular wall separation distance in fetuses with and without VM (nV) with fetal MRI.

METHODS

T2-weighted fetal MRIs of 154 fetuses were retrospectively evaluated. The CP separation was defined as the distance between the medial wall of the dependent ventricle and distal tip of the CP glomus. The measurement was performed at the same plane with the dependent ventricle measurement by two blinded readers.

RESULTS

41 fetuses with VM (mean gestational age 27 (19-35 weeks), and 44 nV fetuses (mean gestational age 28 (20-39 weeks) were included. Interobserver reliability was excellent for ventricle diameters (R = 0.99, confidence interval (CI) 95%) and the separation of CP (R = 0.98, CI 95%). Mean distance of CP separation was 10.7 mm ± 4.2 mm and 3.0 ± 1.6 mm in VM and nV fetuses, respectively (p < 0.001). The distance of CP separation to differentiate VM cases was 6.5 mm (sensitivity: 0.98, specificity: 0.98). Separation of CP was correlated to ventricle diameter in cases with (R = 0.674) and without VM (R = 0.805). For the cut-off value >0.65 cm for the distance between the medial wall of the dependent ventricle and the medial border of choroid plexus sensitivity is 97.56, specificity 95.45, positive predictive value (PPV) 95.20, negative predictive value (NPV) 97.70, and likelihood ratio (LR) (+) is 21.46.

CONCLUSION

Fetal CP can be efficiently evaluated with MRI, and the increase of CP-ventricular wall separation distance in correlation with the ventricle diameter is a reliable sign in the diagnosis of fetal VM.

Outcome of fetuses with prenatal diagnosis of isolated severe bilateral ventriculomegaly: systematic review and meta-analysis

OBJECTIVE

To quantify from the published literature survival and neurodevelopmental outcome of fetuses with prenatally detected isolated severe bilateral ventriculomegaly.

METHODS

MEDLINE, EMBASE and the Cochrane Library were searched electronically. Only cases with a prenatal diagnosis of apparently isolated severe ventriculomegaly and postnatal neurodevelopmental assessment were selected and included. Severe ventriculomegaly was defined as enlargement of the ventricular atria, with a diameter of greater than 15 mm in the transventricular plane. All cases in which the investigators were unable to detect associated structural abnormality, chromosomal abnormality or fetal infection, and in which the ventriculomegaly was therefore regarded as apparently isolated, were included. Those for which the etiology was identified prenatally were excluded, whereas those with postnatal identification of the underlying cause were not excluded, since this information was not available prenatally. The quality of the included studies was assessed using the Newcastle-Ottawa Scale (NOS) for cohort studies. Pregnancy outcomes such as termination, stillbirth, neonatal survival and developmental outcome of the baby, were recorded. The degree of disability was classified as no, mild or severe disability. Statistical assessment was performed by meta-analysis of proportions to combine data, weighting the studies using the inverse variance method and a random-effects model. Proportions and CIs were reported.

RESULTS

Eleven studies including 137 fetuses were found. Twenty-seven pregnancies underwent termination and were excluded. The remaining 110 fetuses with apparently isolated severe ventriculomegaly for which continuation of pregnancy was intended, form the study population. Overall quality assessed using NOS for cohort studies was good. Survival was reported in 95/110 (pooled proportion 87.9% (95% CI, 75.6-96.2%)) cases. In 15/110 (pooled proportion 12.1% (95% CI, 3.8-24.4%)), either stillbirth or neonatal demise was reported. No disability was reported in 41/95 survivors (pooled proportion 42.2% (95% CI, 27.5-57.6%)). However, 17/95 showed mild/moderate disability (pooled proportion 18.6% (95% CI, 7.2-33.8%)) and 37/95 were reported to have severe disability (pooled proportion 39.6% (95% CI, 30.0-50.0%)).

CONCLUSIONS

Four-fifths of fetuses with severe ventriculomegaly survive and, of these, just over two-fifths show normal neurodevelopment. The overall survivors without disability account for more than one third of the total. Given that many cases undergo termination of pregnancy and require longer follow-up in order to detect subtle abnormalities, mortality and prevalence of developmental delay may be even higher than that reported in this paper. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Congenital aqueduct stenosis: Progressive brain findings in utero to birth in the presence of severe hydrocephalus

PURPOSE

To evaluate the effects of progressive hydrocephalus on the developing brain in a cohort of fetuses diagnosed with congenital aqueduct stenosis by comparing prenatal magnetic resonance imaging and postnatal imaging.

METHODS

This IRB approved single center retrospective review of prenatally diagnosed children with congenital aqueduct stenosis interrogated changes in the brain between prenatal and postnatal imaging and analyzed statistics using SAS software package version 9.3.

RESULTS

Thirty fetuses imaged at a mean gestational age of 26 weeks had aqueduct obstruction confirmed by postnatal imaging. Progressive hydrocephalus required shunting in all but one patient (97%). Those patients with increasing hydrocephalus showed increase in ventricular rupture (60%), loss of septal leaflets (47%), and reduction in white matter and corpus callosum volume (43%). Cerebellar ectopia developed in 27% with 6% meeting the criteria for Chiari I malformation.

CONCLUSION

Hydrocephalus in the fetus results in enlarging ventricular rupture, loss of the septum pellucidum leaflets, volume reduction of brain parenchyma including corpus callosum, and risk for Chiari I anomaly. Given advances in fetal surgery and imaging in the last 3 decades, there may be cause to revisit the idea of in utero cerebral spinal fluid diversion as a means to potentially ameliorate progressive loss of the developing brain.

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).

Neuroimaging perspectives on fetal motor behavior

We are entering a new era of understanding human development with the ability to perform studies at the earliest time points possible. There is a substantial body of evidence to support the concept that early motor behaviour originates from supraspinal motor centres, reflects neurological integrity, and that altered patterns of behaviour precede clinical manifestation of disease. Cine Magnetic Resonance Imaging (cineMRI) has established its value as a novel method to visualise motor behaviour in the human fetus, building on the wealth of knowledge gleaned from ultrasound based studies. This paper presents a state of the art review incorporating findings from human and preclinical models, the insights from which, we propose, can proceed a reconceptualisation of fetal motor behaviour using advanced imaging techniques. Foremost is the need to better understand the role of the intrauterine environment, and its inherent unique set of stimuli that activate sensorimotor pathways and shape early brain development. Finally, an improved model of early motor development, combined with multimodal imaging, will provide a novel source of in utero biomarkers predictive of neurodevelopmental disorders.