Fetal eye ultrasound: Normal anatomy, abnormal findings, and clinical impact. / Ultraschall des fetalen Auges: Normale Anatomie, abnorme Befunde und klinische Bedeutung.

Until now, ultrasound examination of the fetal eyes has not played an important role in prenatal diagnosis. National and international guidelines are generally confined to documentation of the presence of the orbits and the lenses. However, in recent years, with the advent of high-resolution ultrasound technology and increasing knowledge of prenatal medicine and genetics, careful examination of the fetal eye has enabled the detection of many ocular malformations before birth. This article provides an overview of the anatomy related to the development of the fetal eye and covers the following conditions: hypertelorism, hypotelorism, exophthalmos, microphthalmos, coloboma, cataract, persistent hyperplastic primary vitreous, retinal detachment, dacryocystocele, and septooptic dysplasia, etc. It is designed to illustrate the spectrum of ocular malformations and their appearance on prenatal ultrasound and to discuss their clinical impact and association with various syndromes.

Synapsin autoantibodies during pregnancy are associated with fetal abnormalities.

Anti-neuronal autoantibodies can be transplacentally transferred during pregnancy and may cause detrimental effects on fetal development. It is unclear whether autoantibodies against synapsin-I, one of the most abundant synaptic proteins, are associated with developmental abnormalities in humans. We recruited a cohort of 263 pregnant women and detected serum synapsin-I IgG autoantibodies in 13.3% using cell-based assays. Seropositivity was strongly associated with abnormalities of fetal development including structural defects, intrauterine growth retardation, amniotic fluid disorders and neuropsychiatric developmental diseases in previous children (odds ratios of 3-6.5). Autoantibodies reached the fetal circulation and were mainly of IgG1/IgG3 subclasses. They bound to conformational and linear synapsin-I epitopes, five distinct epitopes were identified using peptide microarrays. The findings indicate that synapsin-I autoantibodies may be clinically useful biomarkers or even directly participate in the disease process of neurodevelopmental disorders, thus being potentially amenable to antibody-targeting interventional strategies in the future.

Ultrasound Diagnosis of Malformations of the Fetal Kidneys and Urinary System. / Die Ultraschalldiagnostik von Fehlbildungen der fetalen Nieren und des harnableitenden Systems.

Malformations of the fetal kidneys and urinary system are common and easily visualized and diagnosed on ultrasound. This article presents the typical sonographic findings of these abnormalities during the various stages of pregnancy. Because malformations of the urogenital tract often have an association with genetic diseases/ciliopathies, these are also discussed. To complete the article, we provide a brief overview of the normal anatomy of the kidneys and urinary system. The normal anatomy and malformations of the genitalia will not be discussed in this article due to their complexity.

WAPM-World Association of Perinatal Medicine Practice Guidelines: Fetal central nervous system examination.

These practice guidelines follow the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the ultrasound assessment of the fetal Central Nervous System (CNS) anatomy. In fact, this document provides further guidance for healthcare practitioners for the evaluation of the fetal CNS during the mid-trimester ultrasound scan with the aim to increase the ability in evaluating normal fetal anatomy. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world, and serves as a guideline for use in clinical practice.

A novel mutation in NEB causing foetal nemaline myopathy with arthrogryposis during early gestation.

Nemaline myopathies are a clinically and genetically heterogeneous group of congenital myopathies, mainly characterized by muscle weakness, hypotonia and respiratory insufficiency. Here, we report a male foetus of consanguineous parents with a severe congenital syndrome characterized by arthrogryposis detected at 13 weeks of gestation. We describe severe complex dysmorphic facial and musculoskeletal features by post mortem fetal examination confirming the prenatal diagnosis. Histomorphological and ultrastructural studies of skeletal muscle reveal mini-rods in myotubes caused by a novel homozygous splice-site mutation in NEB (NM_001164508, chr2:g.152,417,623C>A GRCh37.p11 | c.19,102-1G>T ENST00000397345.3). No rods were seen in the myocardium. We discuss the relevance of this mutation in the context of nemaline myopathies associated with early developmental musculoskeletal disorders.

Recent Development in Three and Four Dimension Fetal Echocardiography.

Since its introduction >15 years ago, the use of spatial and temporal image correlation (STIC) technology has contributed substantially to fetal echocardiography. Moreover, significant advances have occurred in 3- and 4-dimensional (3D/4D) echocardiography over the past several years including the matrix probe along with advances in gray scale and color Doppler post processing, resulting in improved display of ultrasound images. In this article, we provide examples to show these recent developments including the use of color Doppler with STIC in the glass-body mode and the matrix probe thus enabling the demonstration of cardiac anomalies of the 4-chamber-view and great arteries. The use of the matrix probe allows the examination of cardiac structures in 2 orthogonal planes simultaneously, which can help in display of anatomy side by side (Biplane mode). In addition, the rapid image reconstruction of the matrix probe allows for the display of live 4D and the rapid acquisition of a STIC volume. The display of multiplanar images of the heart in 3D/4D has also been used to automate the display of ultrasound images, resulting in standardization of the image display and thus minimizing the operation dependency of the ultrasound examination. Future addition of image recognition software can also provide assistance in image review.

Exome sequencing of fetal anomaly syndromes: novel phenotype-genotype discoveries.

The monogenic etiology of most severe fetal anomaly syndromes is poorly understood. Our objective was to use exome sequencing (ES) to increase our knowledge on causal variants and novel candidate genes associated with specific fetal phenotypes. We employed ES in a cohort of 19 families with one or more fetuses presenting with a distinctive anomaly pattern and/or phenotype recurrence at increased risk for lethal outcomes. Candidate variants were identified in 12 families (63%); in 6 of them a definite diagnosis was achieved including known or novel variants in recognized disease genes (MKS1, OTX2, FGFR2, and RYR1) and variants in novel disease genes describing new fetal phenotypes (CENPF, KIF14). We identified variants likely causal after clinical and functional review (SMAD3, KIF4A, and PIGW) and propose novel candidate genes (PTK7, DNHD1, and TTC28) for early human developmental disease supported by functional and cross-species phenotyping evidence. We describe rare and novel fetal anomaly syndromes and highlight the diagnostic utility of ES, but also its contribution to discovery. The diagnostic yield of the future application of prenatal ES will depend on our ability to increase our knowledge on the specific phenotype-genotype correlations during fetal development.

Further evidence for complex inheritance of holoprosencephaly: Lessons learned from pre- and postnatal diagnostic testing in Germany.

Holoprosencephaly (HPE) has been defined as a distinct clinical entity with characteristic facial gestalt, which may-or may not-be associated with the true brain malformation observed postmortem in autopsy or in pre- or postnatal imaging. Affected families mainly show autosomal dominant inheritance with markedly reduced penetrance and extremely broad clinical variability even between mutation carriers within the same families. We here present advances in prenatal imaging over the last years, increasing the proportion of individuals with HPE identified prenatally including milder HPE forms and more frequently allowing to detect more severe forms already in early gestation. We report the results of diagnostic genetic testing of 344 unrelated patients for HPE at our lab in Germany since the year 2000, which currently with the application of next generation sequencing (NGS) panel sequencing identifies causal mutations for about 31% (12/38) of unrelated individuals with normal chromosomes when compared to about 15% (46/306) using conventional Sanger sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA). More comprehensive genetic testing by our in house NGS panel sequencing of 10 HPE associated genes (MiSeq™ and NextSeq™500, Illumina, Inc., San Diego, CA) not only allowed to include genes with smaller contribution to the phenotype, but may also unravel additional low frequency or more common genetic variants potentially contributing to the observed large intrafamiliar variability and may ultimately guide our understanding of the individual clinical manifestation of this complex developmental disorder.

Relationship Between Cavum Septi Pellucidi Measurements and Fetal Hypoplastic Left Heart Syndrome or Dextro-Transposition of the Great Arteries.

OBJECTIVES: The aim of this study was to compare the size and position of the cavum septi pellucidi (CSP) in fetuses with hypoplastic left heart syndrome (HLHS) or dextro-transposition of the great arteries (d-TGA) with healthy fetuses. METHODS: The CSP length, CSP width, and frontal lobe length were measured in 185 healthy fetuses (404 scans), 11 fetuses with HLHS (16 scans), and 11 fetuses with d-TGA (12 scans) between January 2005 and April 2016. Each measurement was compared between healthy fetuses and those with HLHS or d-TGA, controlling for the biparietal diameter. RESULTS: Positive correlations were noted between biparietal diameter and CSP length, CSP width, and frontal lobe length (adjusted R2 = 0.811, 0.821, and 0.878, respectively). An increased CSP length was found in both fetuses with HLHS and those with d-TGA (P < .0001). The CSP width was only increased in fetuses with d-TGA (P = .0466). No difference in the frontal lobe length was noted. CONCLUSIONS: In fetuses with HLHS, the CSP is increased in length. In fetuses with d-TGA, the CSP is increased in both length and width.

Bovine aortic arch: clinical significance and hemodynamic evaluation.

OBJECTIVE: The most common aortic arch branching variation described in literature is the common origin of the brachiocephalic trunk and left common carotid artery ("bovine arch" / type II aortic arch), with an incidence of 7.2-21.1%. The first aim of this study was to investigate the prevalence of bovine arch in the fetuses. The second aim was the hemodynamic evaluation of the epiaortic vessels. METHODS: In two years we examined 742 pregnant women and it was possible to obtain a good hemodynamic evaluation in 39 patients. Among the 39 fetuses, we found 6 with bovine arch. The blood flow of all epiaortic vessels and of MCA was evaluated. RESULTS: Among the 742 fetuses examined, the bovine aortic arch was identified in 45 patients (6.06%). The hemodynamic evaluation of the epiaortic vessels showed statistically significant differences between the bovine arch and normal aortic arch. CONCLUSION: The presence of bovine aortic arch in the fetus is characterized by some hemodynamical differences. They could have a possible relationship with the incidence of some pathologies in adult life. Prenatal knowledge of anatomic variants of the aortic arch can bring benefits to the individual's health for future possible cardiovascular investigations.

Detection of Spina Bifida by First Trimester Screening - Results of the Prospective Multicenter Berlin IT-Study.

Purpose To evaluate the potential of routine assessment of intracranial translucency (IT) and other posterior brain parameters in the early detection of open spina bifida during the 11 - 14 weeks screening examination. Materials and Methods This prospective, multicenter longitudinal study was conducted with the participation of 20 certified DEGUM II or III experts in Berlin, Germany, between June 2010 and October 2013. All pregnant women undergoing a first trimester screening were included in the study and in every patient were the IT, brain stem (BS), cisterna magna (CM), BS to occipital bone distance (BSOB) and BS/BSOB ratio measured. All patients with continuing pregnancy underwent a second trimester scan. Our data was used to develop our own reference ranges. The primary outcome parameter was the presence of open spina bifida. Results A total of 15 526 women with 16 164 fetuses were examined. Median of the IT was 2.1 mm, of the CM 1.6 mm, of the BS 2.7 mm, of the BSOB 5.5 mm, and of the BS/BSOB ratio 0.49. There were 11 cases with open spina bifida (incidence of 6.8/10 000). The detection rate was 100 % and in all cases of spina bifida, the anomaly was detected either at the first examination (n = 8) or considered suspicious and the lesion then detected a few weeks later (n = 3). Considering individual measurements, however, the detection rate was 18 % with the complete absence of the IT and 45 % with cut-off values. For the CM measurement, the detection rate was 64 % with the absence of the CM and 73 % with cut-off values. The other parameters proved not to be predictive of open spina bifida. Conclusion In the hands of an expert, open spina bifida can be reliably diagnosed early in gestation during the 11 - 14 weeks screening. The measurement of different parameters of the posterior brain, especially the CM and the use of cut-off values are of tremendous benefit in achieving a high sensitivity in the detection rate.

Dilated cavum septi pellucidi in fetuses with microdeletion 22q11.

OBJECTIVES: The cavum septi pellucidi (CSP) is an easily recognizable landmark in the fetal brain. CSP disappears after birth to form the septum pellucidum. Children with microdeletion 22q11 (del. 22q11) were, however, reported to have a persistent dilated CSP. This study was designed to examine whether the CSP is dilated in fetuses with del.22q11. METHODS: This was a case-control study where the CSP width was measured in normal fetuses from 16 to 34 weeks and in fetuses with del. 22q11. CSP width was correlated to the biparietal diameter (BPD). Reference curves were constructed, and z-scores calculated. RESULTS: Cavum septi pellucidi width in 260 normal fetuses showed a linear correlation with BPD. The study group consisted of 37 fetuses with del. 22q11. In 25/37 (67.5%) of fetuses with del. 22q11, the CSP was enlarged with a mean z-score of 2.64 (p < 0.0001). Fetuses with a BPD > 50 mm (>22 weeks of gestation) had a dilated CSP in 85.7% (24/28). CONCLUSIONS: The CSP is a structure routinely evaluated in screening ultrasound. A wide CSP is found in second trimester fetuses with del. 22q11. A dilated CSP may be an important sonographic marker for the presence of del. 22q11 along with conotruncal malformations and thymic hypoplasia. © 2016 John Wiley & Sons, Ltd.

Fluid area measurements in the posterior fossa at 11-13 weeks in normal fetuses and fetuses with open spina bifida.

OBJECTIVES: To measure the area of the intracranial translucency (IT) (syn: 4th ventricle) and the future cisterna magna (CM) in normal fetuses and to compare with fetuses with open spina bifida. PATIENTS: In the midsagittal plane of the face of 220 fetuses between 11 and 13 weeks' gestation, the areas of the IT and CM were measured and the sum, defined as the posterior fossa fluid (PFF) area was calculated. Reference ranges were constructed in relation to the crown-rump length. The study group consisted of 21 fetuses with open spina bifida and showed in all cases a single pocket of fluid in the posterior fossa. Fetuses with no fluid in the fossa were excluded. This PFF-area was measured and compared with the reference range of the IT-area and the PFF-area of normal fetuses and Z-scores were calculated. RESULTS: In normal fetuses, a significant increase of the IT-, the CM- and the PFF-area was found as a sign of the expanding posterior fossa. The mean PFF-area increased from 8.55 to 29.72 mm(2) in the observation period. Fetuses with open spina bifida had reduced fluid in the posterior fossa with values ranging between 2.39 and 5.08 mm(2) and significantly lower Z-scores. CONCLUSIONS: Fetuses with open spina bifida have an abnormally small posterior fossa at 11-13 weeks' and in cases where the cerebrospinal fluid is still present, the fluid area in the midsagittal plane is reduced when compared to normal fetuses. Area fluid assessment can be an additional useful measurement in suspicious cases for open spina bifida in early gestation.

Fetal cardiac axis and congenital heart defects in early gestation.

OBJECTIVE: To investigate the association between cardiac axis and fetal congenital heart defects to demonstrate the potential clinical applicability of cardiac axis measurement for detection of congenital heart defect in early gestation. METHODS: This case-control study was undertaken in three tertiary centers with expertise in fetal imaging in early gestation. Fetal cardiac axis was evaluated between 11 0/7 and 14 6/7 weeks of gestation in 197 fetuses with confirmed congenital heart defects. A control group was selected by matching each fetus with a congenital heart defect with two fetuses in the control group with similar crown-rump length (± 5 mm) and date of study (± 2 months). Cardiac axis was measured on the four-chamber view as the angle between the line that traces the long axis of the heart and the line that bisects the thorax in an anteroposterior direction. RESULTS: In the control group, mean cardiac axis was 44.5 ± 7.4°. The cardiac axis did not significantly change in early pregnancy. In the congenital heart defect group, 25.9% of fetuses had cardiac axis measurements within normal limits. In 74.1%, the cardiac axis was abnormal including 110 fetuses in the case group with left deviation (cardiac axis > 97.5th percentile), 19 fetuses in the case group with right deviation (cardiac axis < 2.5th percentile), and 17 fetuses in the case group with nonidentifiable cardiac axis. The performance of cardiac axis measurement in detection of major congenital heart defect was significantly better than enlarged nuchal translucency, tricuspid regurgitation, or reversed A-wave in ductus venosus used alone or in combination. CONCLUSION: Abnormal cardiac axis is present in two-thirds of fetuses with congenital heart defect in early gestation. Adding cardiac axis assessment to the nuchal translucency measurement is helpful in defining a population at risk for fetal congenital heart defect.