An unusual presentation of de novo RAC3 variation in prenatal diagnosis

Pathogenic variants in RAC3 cause a neurodevelopmental disorder with brain malformations and craniofacial dysmorphism, called NEDBAF. This gene encodes a small GTPase, which plays a critical role in neurogenesis and neuronal migration. We report a 31 weeks of gestation fetus with triventricular dilatation, and temporal and perisylvian polymicrogyria, without cerebellar, brainstem, or callosal anomalies. Trio whole exome sequencing identified a RAC3 (NM_005052.3, GRCh38) probably pathogenic de novo variant c.276 T>A p.(Asn92Lys). Eighteen patients harboring 13 different and essentially de novo missense RAC3 variants were previously reported. All the patients presented with corpus callosum malformations. Gyration disorders, ventriculomegaly (VM), and brainstem and cerebellar malformations have frequently been described. The only previous prenatal case associated with RAC3 variant presented with complex brain malformations, mainly consisting of midline and posterior fossa anomalies. We report the second prenatal case of NEDBAF presenting an undescribed pattern of cerebral anomalies, including VM and polymicrogyria, without callosal, cerebellar, or brainstem malformations. All neuroimaging data were reviewed to clarify the spectrum of cerebral malformations.

Prenatal imaging of the normal and abnormal spinal cord: recommendations from the Fetal Task Force of the European Society of Paediatric Radiology (ESPR) and the European Society of Neuroradiology (ESNR) Pediatric Neuroradiology Committee

Spinal dysraphisms are amenable to diagnosis in utero. The prognosis and the neonatal management of these conditions differ significantly depending on their types, mainly on the distinction between open and closed defects. A detailed evaluation not only of the fetal spine, but also of the brain, skull, and lower limbs is essential in allowing for the right diagnosis. In this article, recommendations from the Fetal Task Force of the European Society of Paediatric Radiology (ESPR) and the European Society of Neuroradiology (ESNR) Pediatric Neuroradiology Committee will be presented. The aim of this paper is to review the imaging features of the normal and abnormal fetal spinal cord, to clarify the prenatal classification of congenital spinal cord anomalies and to provide guidance in their reporting.

Reversed cortico-medullary differentiation in the fetal and neonatal kidneys: an indicator of poor prognosis?

BACKGROUND

Bilateral reversed cortico-medullary differentiation is rarely observed on fetal or neonatal renal ultrasound and is therefore a diagnostic challenge.

OBJECTIVE

Our purpose was to widen the differential diagnoses of fetal and neonatal nephropathies introducing reversed cortico-medullary differentiation as a clue either on obstetric US or during follow-up of hyperechoic kidneys in order to improve the management of such rare clinical situations.

MATERIALS AND METHODS

We retrospectively reviewed the US images of 11 patients showing bilateral reversed cortico-medullary differentiation on prenatal examination or in which this pattern developed postnatally in the follow-up of fetal hyperechoic kidneys. For each patient, a precise diagnosis was established either on clinical assessment or, when available, on histological or genetic findings.

RESULTS

Six fetuses displayed bilateral reversed cortico-medullary differentiation on obstetric examination, and the pattern persisted throughout pregnancy. In the five other fetuses, the kidneys appeared initially homogeneously hyperechoic; this evolved into reversed cortico-medullary differentiation during the third trimester in two cases and shortly after birth in three cases. Two pregnancies were terminated because of estimated poor prognosis. In the nine surviving neonates, four died of renal failure in the post-natal period. The clinical evolution was more favorable in the remaining five newborns.

CONCLUSIONS

Six different diagnoses were established in patients presenting with a reversed cortico-medullary differentiation renal pattern. This finding was associated with poor outcome in six cases. An acute prenatal diagnosis of reversed cortico-medullary differentiation improves pre- and postnatal work-up and guides counseling and genetic testing.

Fetal uropathies: pre- and postnatal imaging, management and follow-up

Congenital uropathies are the most common fetal anomalies. They include a wide spectrum of anomalies ranging from mild pelvis dilation to complex urinary tract malformations. Prenatal imaging not only allows for their diagnosis but, in experienced hands, it can differentiate obstructive from refluxing or malformative uropathies. Such precise prenatal information allows for intervention before birth in select cases or for adapting the postnatal workup to provide a better long-term outcome. For the different types of congenital uropathies, we describe their prenatal presentations on US and the complementary role of fetal MRI where indicated. We correlate these findings with postnatal workup and summarize the updated neonatal diagnostic and clinical/surgical management.

Exploration of the fetal skeleton by ultra-low-dose computed tomography: guidelines from the Fetal Imaging Task Force of the European Society of Paediatric Radiology

Skeletal anomalies are rare, requiring a systematic ultrasound (US) examination of each skeletal part when there is suspicion of a skeletal dysplasia. Although US examination can provide good evaluation of the fetal bones and cartilage, ultra-low-dose three-dimensional (3-D) multi-detector computed tomography (CT) is a useful complementary tool that can significantly improve prenatal diagnostic accuracy in select cases. Given that ultra-low-dose fetal CT remains an irradiating technique, indications should result from a multidisciplinary consensus, acquisition protocols should be optimized and the reporting standardized. In this paper we discuss guidelines from the Fetal Imaging Task Force of the European Society of Paediatric Radiology for indications, protocols and reporting of ultra-low-dose fetal CT.

Indications for magnetic resonance imaging of the fetal body (extra-central nervous system): recommendations from the European Society of Paediatric Radiology Fetal Task Force

The indications for fetal body MRI are amplifying because of the expanding possibilities of fetal and perinatal therapy. However, huge heterogeneity regarding the indications for fetal body MRI is seen among different European countries that is mostly related to local use of US, but also to local fetal MRI expertise and legislation on pregnancy termination. The purpose of this article is to summarize the precise indications for fetal MRI, excluding the central nervous system. MRI indications arise from the sonographic findings, based on the operator's experience and the various practices in the countries and institutions represented on the European Society of Paediatric Radiology Fetal Task Force. We also highlight the strengths and weaknesses of fetal US and MRI of the fetal body.

Fetal magnetic resonance imaging at 3 Tesla - the European experience

BACKGROUND

The Fetal Imaging Taskforce was established in 2018 by the European Society of Paediatric Radiology. The first survey on European practice of fetal imaging published in 2020 revealed that 30% of fetal magnetic resonance imaging (MRI) is performed at 3 tesla (T). The purpose of this second survey was to identify the impact of 3-T fetal MRI with an emphasis on image quality, diagnostic yield, and technical challenges and artifacts at higher field strengths.

OBJECTIVE

To describe the prenatal imaging practice at 3-T MRI units in various centres in Europe and to prepare recommendations on behalf of the Fetal Imaging Taskforce.

MATERIALS AND METHODS

A survey was sent to all members performing 3-T fetal MRI. Questions included practitioner experience, magnet brand, protocols, counselling, artifacts and benefits of imaging at higher field strengths.

RESULTS

Twenty-seven centres replied and reported improved spatial resolution and improved signal-to-noise ratio when performing fetal MRI at 3 T. Shading and banding artifacts and susceptibility to motion artifacts were common problems identified by practitioners at the higher field strength. For all neurological indications, practitioners reported a benefit of imaging at 3 T, most marked for posterior fossa evaluation and parenchymal lesions.

CONCLUSION

The use of 3-T magnets in fetal MRI has improved the availability and quality of advanced imaging sequences and allowed for better anatomical evaluation. There remain significant challenges to minimize the impact of artifacts on image quality. This paper includes guidelines for clinical practice and imaging at 3 T.

A prenatal case of lissencephaly with cerebellar hypoplasia: New mutation in RELN gene

Reelinopathies cause a distinctive lissencephaly type associated with cerebellar hypoplasia. To help further management, we wanted to report here the first prenatal diagnosis due to a homozygous inherited reelinopathy.

Implementation of fetal clinical exome sequencing: Comparing prospective and retrospective cohorts

PURPOSE

We compared the diagnostic yield of fetal clinical exome sequencing (fCES) in prospective and retrospective cohorts of pregnancies presenting with anomalies detected using ultrasound. We evaluated factors that led to a higher diagnostic efficiency, such as phenotypic category, clinical characterization, and variant analysis strategy.

METHODS

fCES was performed for 303 fetuses (183 ongoing and 120 ended pregnancies, in which chromosomal abnormalities had been excluded) using a trio/duo-based approach and a multistep variant analysis strategy.

RESULTS

fCES identified the underlying genetic cause in 13% (24/183) of prospective and 29% (35/120) of retrospective cases. In both cohorts, recessive heterozygous compound genotypes were not rare, and trio and simplex variant analysis strategies were complementary to achieve the highest possible diagnostic rate. Limited prenatal phenotypic information led to interpretation challenges. In 2 prospective cases, in-depth analysis allowed expansion of the spectrum of prenatal presentations for genetic syndromes associated with the SLC17A5 and CHAMP1 genes.

CONCLUSION

fCES is diagnostically efficient in fetuses presenting with cerebral, skeletal, urinary, or multiple anomalies. The comparison between the 2 cohorts highlights the importance of providing detailed phenotypic information for better interpretation and prenatal reporting of genetic variants.

Indications for magnetic resonance imaging of the fetal central nervous system: recommendations from the European Society of Paediatric Radiology Fetal Task Force

Fetal central nervous system MRI is a well-established method to complement a high-quality fetal ultrasound and to clarify sonographically detected abnormalities in complex pregnancies. However, there is still worldwide heterogeneity and confusion regarding the indications of fetal central nervous system MRI, which has roots in differences among countries regarding the performance of ultrasound examinations and legislation on pregnancy termination. The purpose of this article is to clarify the indications for fetal central nervous system MRI by focusing on the ultrasound findings that guide further investigation with MRI and highlight the strengths and the weaknesses of each modality on imaging the fetal central nervous system.

Spontaneous resolution of nonimmune hydrops fetalis in a fetus with TP63 gene mutation and LZTR1 gene variants

In cases of fetal hydrops, searching for an etiology is essential to evaluate the fetal prognosis and propose the most appropriate management.

TrkA mediates effect of novel KIDINS220 mutation in human brain ventriculomegaly

Congenital hydrocephalus is a potentially devastating, highly heterogeneous condition whose genetic subset remains incompletely known. We here report a consanguineous family where three fetuses presented with brain ventriculomegaly and limb contractures and shared a very rare homozygous variant of KIDINS220, consisting of an in-frame deletion of three amino acids adjacent to the fourth transmembrane domain. Fetal brain imaging and autopsy showed major ventriculomegaly, reduced brain mass, and with no histomorphologic abnormalities. We demonstrate that the binding of KIDINS220 to TrkA is diminished by the deletion mutation. This family is the second that associates a KIDINS220 genetic variant with human ventriculomegaly and limb contractures, validating causality of the gene and indicating TrkA as a likely mediator of the phenotype.

Middle interhemispheric variant of holoprosencephaly: First prenatal report of a ZIC2 missense mutation

We present a case of a middle interhemispheric variant of antenatal discovery associated with a de novo missense variant (NM_007129.5: c.1109G>A p.(Cys370Tyr)) in the ZIC2 gene. Our case represents the first prenatal description of a ZIC2 missense mutation found in association with syntelencephaly.

Heterogeneous colonic content: A prenatal sonographic manifestation of lysinuric protein intolerance

We report a fetus with heterogeneous colonic content, an isolated sonographic prenatal sign of lysinuric protein intolerance, a very rare metabolic disease. Familial genetic enquiries confirmed heterozygote mutation in the implicated gene in parents. The prenatal diagnosis led to neonatal dietary adaptation and avoided acute complications.

Severe congenital non-syndromic ichthyosis: ultrasound diagnosis of a prenatal case

Background

Prenatal diagnosis of congenital ichthyosis is still a challenge and very few cases of sonographic diagnosis have been described in the literature. Diagnosis by fetal ultrasound is made from the late second trimester and prenatal genetic diagnosis can be possible only if a proband is known.

Case presentation

We report the case of a prenatal diagnosis of severe non-syndromic ichthyosis in a primigravida woman with no personal or family history for this pathology.

Conclusion

Our case outlines prenatal sonographic signs suggestive of ichthyosis orienting genetic diagnosis.

Agenesis of olfactory bulbs: A forgotten diagnostic indicator of acampomelic campomelic dysplasia

Campomelic dysplasia (CD) and its variant acampomelic campomelic dysplasia (ACD) are caused by SOX9 haploinsufficiency. This gene encodes a transcription factor crucial for embryogenesis and primarily expressed in the olfactory bulbs. The detection of agenesis of olfactory bulbs could help establish a prenatal diagnosis of CD or ACD, although prevalence of this sign remains unknown.

Prenatal ultrasonography of autosomal dominant polycystic kidney disease mimicking recessive type: case series

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited renal disease. This pathology has been increasingly diagnosed in utero and several sonographic patterns are well described in the literature.

OBJECTIVE

To present a series of fetuses with an unusual imaging pattern of ADPKD, mimicking autosomal recessive polycystic kidney disease (ARPKD).

MATERIALS AND METHODS

We retrospectively reviewed second-line ultrasound (US) scans performed for suspicion of fetal kidney pathology between 2006 and 2018. Inclusion criteria were (1) proven ADPKD on the basis of a known family history and/or of genetic testing and (2) US features suggestive of ARPKD. We recorded the clinical, imaging, genetic and pathological findings in cases with pregnancy termination.

RESULTS

Three out of 12 patients with proven ADPKD diagnosed in utero presented with US features suggestive of ARPKD. Furthermore, an additional patient observed at another institution was added to the series. History of familial ADPKD was present in three cases. US showed enlarged kidneys with increased cortical echogenicity, decreased corticomedullary differentiation, multiple medullary cysts and decreased amniotic fluid in all four cases. Pregnancy was terminated in two cases (histology confirmed features in keeping with ADPKD), one premature neonate died (histology in progress) and one child is alive. Genetic testing showed a homozygous mutation of the PKD1 gene in two patients, a heterozygous mutation of the PKD1 gene in one patient and was not performed in the remaining patient.

CONCLUSION

This series describes an unusual sonographic prenatal presentation of ADPKD, not yet well described in the radiologic literature, mimicking ARPKD.

Prenatal Evaluation and Postnatal Follow-Up of Ureteral Ectopic Insertion in Multicystic Dysplastic Kidneys

OBJECTIVE

To emphasize the need for analyzing the pelvis when a unilateral multicystic dysplastic kidney (MCDK) is observed at prenatal ultrasonography (US) because of possible associated ectopic ureteral insertion.

METHODS

We performed a retrospective study including prenatal US diagnosis of unilateral MCDK and retrovesical cyst. The following data were recorded: pre- and postnatal US, magnetic resonance imaging (MRI), and voiding cystourethrography (VCUG) findings. The shape of the pelvic cyst was analyzed as well as the visibility of the ureteral insertion into the cyst.

RESULTS

Fourteen patients were included (7 females). At prenatal US, the cyst wall was smooth in 8 cases (6 females) and lobulated in 5 cases (4 males). In 1 case it protruded into the bladder. Ectopic ureteral insertion was observed in 2 cases. Prenatal MRI (n = 6) depicted ureteral insertion in 2 more cases. Postnatal US (n = 14) showed the same cyst patterns as prenatally, ectopic ureteral insertion (n = 8), and duplicated uterus (n = 4). Postnatal MRI (n = 7) always depicted the ureteral ectopic insertion into the cyst. VCUG (n = 5) showed indirect findings of ectopic ureteral insertion (n = 3).

CONCLUSION

Unilateral MCDK should lead to search for a retrovesical cyst corresponding most commonly to a distended hemivagina or a seminal vesicle. Early diagnosis of this condition leads to better clinical management.

Unusual association of brain hemorrhage and digestive tract occlusion: about two prenatal cases

We report two prenatal cases of an exceptional association of digestive tract atresia or perforation with brain hemorrhage. This combination worsens the prognosis leading to termination of pregnancy in one case. We outline the importance of a careful fetal brain examination on imaging in cases of prenatal “acute” abdominal insults.

Kasabach-Merritt phenomenon and prenatal counseling: a case series

Kasabach–Merritt phenomenon can be encountered in the perinatal period. No consensus exists regarding prenatal management. We report one prenatal case leading to therapeutic abortion and one neonatal case, successfully treated by a multimodal therapy. Prenatal counseling should include the possibility of neonatal multimodal treatment that can lead to favorable outcomes.

[Diastematomyelia diagnosed prenatally]

We report a case of a 32-week-old foetus affected by diastematomyelia. A third trimester echography suggested a spine abnormality. Further investigations by CT-scanner and MRI were performed to precise the anomaly and to better counsel the couple on the prognosis. We performed a review of the literature about embryological hypotheses, clinical presentations, antenatal investigations and prognosis of such a rare spinal malformation.

An unusual case of congenital cardiac cyst of the interventricular septum

We present a very rare case of a neonatal multiple haemangiomatosis with a cystic interventricular cardiac haemangioma. An anechoic cyst of 10 mm of diameter, located in the superior third of the interventricular septum was found by foetal echocardiography at 30 weeks of pregnancy. The baby was born at 39 weeks of pregnancy and the skin was covered with multiple purple cutaneous haemangiomas. As neonatal haemangiomatosis may be associated with visceral haemangiomas, the diagnosis of cardiac haemangioma was considered and transthoracic echocardiography revealed a translucent cyst consistent with this diagnosis. At 6 months of age, the cardiac mass was barely visible and most cutaneous lesions had regressed without treatment. Cardiac haemangiomas must be considered in the diagnosis of cystic masses, and the present case emphasizes the tendency towards spontaneous regression of these lesions.

[Postnatal evaluation and management of fetal pyelectasis on prenatal ultrasound]

Fetal pyelectasis is the most frequently encountered anomaly on prenatal ultrasound. The ultrasound diagnostic criteria are well established: nature of dilated structures, degree of dilatation, ultrasound appearance of the kidneys, volume of amniotic fluid. Ultrasound can also determine if the anomaly is isolated or not, which is important for the management and prognosis of the pregnancy. Ultrasound is the initial postnatal study to evaluate the urinary tract. Further management will be based on suspected diagnosis. In cases of suspected vesico-ureteral reflux, VCUG is performed. In cases of obstructive uropathy or complex malformation (duplications), MRI is performed at 6 months of age to further define the anatomy of the urinary tract. Radionuclide renogram, performed in most cases, allows evaluation of split renal function. Follow-up ultrasound is important to monitor renal development, urinary tract dilatation and appearance of the renal parenchyma. Functional follow-up is assured by radionucline renography. This comprehensive follow-up is recommended to prevent complications and progressive loss of renal function.

Antenatal embolization of a large chorioangioma by percutaneous Glubran 2 injection

We describe a case of a large chorioangioma diagnosed at 18 weeks' gestation. Because of advanced fetal heart failure at 23 weeks' gestation, embolization of the chorioangioma's vessels was performed by percutaneous injection of Glubran 2 surgical glue. There was no immediate secondary effect of treatment. Devascularization was complete and durable. Signs of fetal cardiac failure normalized after 1 month and a healthy infant was delivered at 38 weeks. To our knowledge this is the first reported case of perinatal survival after successful embolization of a chorioangioma using tissue glue.

[Imaging of urinary tract infection in children]

Urinary tract infection is very common in children. Its diagnosis, management and treatment have led to abundant literature and many controversies. The main challenges are to identify patients at risk of infection and those at risk of complicated infections. Long-term complications include reflux nephropathy, renal hypertension and stage renal disease. Imaging has a triple role: to confirm the diagnosis in patients with equivocal clinical symptoms; to determine patients at risk of recurrence; prevention of infection by detecting already in utero patients with congenital malformation. During the acute phase, Ultrasound has an important role in detecting favouring conditions such as urinary tract dilatation. The use of color Doppler increases the sensibility and specificity of ultrasound. To date, DMSA scan is the key examination for demonstrating the parenchymal lesions. CT-scan and MRI are rarely used in this acute phase. Retrograde voiding cystography (RVC) will be used whenever vesico-ureteric reflux is suspected. A decision algorithm can be proposed bases on US and DMSA; RVC will be performed whenever one of them is positive. CT or MRI will be used to look for abscesses complicating the UTI. DMSA scan is the gold standard for detecting renal scanning, sequellae of the infection. In the future, the role of MRI will surely increase for the demonstration of uropathy acute and sequelae of the renal involvement.

Fetal gastrointestinal MRI: all that glitters in T1 is not necessarily colon

BACKGROUND

It has been described that both the colon and distal ileum present with a physiological hypersignal on T1-weighted sequences during the second and third trimesters of pregnancy because of their protein-rich meconium content, it was unclear whether the normal characteristics that have been described on fetal MRI can be applied to gastrointestinal (GI) obstructions.

OBJECTIVE

To analyse the localisation value of T1 hypersignal within dilated bowel loops in fetuses with gastrointestinal tract obstruction.

MATERIALS AND METHODS

A retrospective 4-year multicentre study analysing cases of fetal GI obstruction in which MRI demonstrated T1 hypersignal content in the dilated loops. Data collected included gestational age (GA) at diagnosis, bowel appearance on US, CFTR gene mutations and amniotic levels of gastrointestinal enzymes. The suggested prenatal diagnosis was eventually compared to postnatal imaging and surgery.

RESULTS

Eleven patients were included. The median GA at US diagnosis was 23 weeks (range 13-32). In eight cases there was a single dilated loop, while several segments were affected in three. The median GA at MRI was 29 weeks (range 23-35). One case presented with cystic fibrosis mutations. Final prenatally suspected diagnoses were distal ileal atresia or colon in nine cases and proximal atresia in two. Postnatal findings were proximal jejunal atresia in nine cases and meconium ileus in two. In five cases the surgical findings demonstrated short bowel syndrome.

CONCLUSION

In cases of fetal occlusion, T1 hypersignal should not be considered as a sign of distal ileal or colonic occlusion. The obstruction may be proximal, implying a risk of small bowel syndrome, which requires adequate parental counselling.

Magnetic resonance imaging in the prenatal diagnosis of congenital diarrhea

OBJECTIVE

Congenital diarrhea is very rare, and postnatal diagnosis is often made once the condition has caused potentially lethal fluid loss and electrolyte disorders. Prenatal detection is important to improve the immediate neonatal prognosis. We aimed to describe the prenatal ultrasound and magnetic resonance (MRI) imaging findings in fetuses with congenital diarrhea.

METHODS

The study reports the pre- and postnatal findings in four fetuses that presented with generalized bowel dilatation and polyhydramnios. We analyzed the fetal ultrasound and MRI examinations jointly, then compared our provisional diagnosis with the amniotic fluid biochemistry and subsequently with the neonatal stool characteristics.

RESULTS

In each of the four cases an ultrasound examination between 22 and 30 weeks' gestation showed moderate generalized bowel dilatation and polyhydramnios suggesting intestinal obstruction. MRI examinations performed between 24 and 32 weeks' gestation confirmed that the dilatation was of gastrointestinal (GI) origin, with a signal indicating intraluminal water visible throughout the small bowel and colon. The expected hypersignal on T1-weighted sequences characteristic of physiological meconium was absent in the colon and rectum. This suggested that the meconium had been completely diluted and flushed out by the water content of the bowel. The constellation of MRI findings enabled a prenatal diagnosis of congenital diarrhea. The perinatal lab test findings revealed two cases of chloride diarrhea and two of sodium diarrhea.

CONCLUSION

Congenital diarrhea may be misdiagnosed as intestinal obstruction on prenatal ultrasound but has characteristic findings on prenatal MRI enabling accurate diagnosis; this is important for optimal neonatal management.

Neonatal hemochromatosis and Martinez-Frias syndrome of intestinal atresia and diabetes mellitus in a consanguineous newborn

Neonatal hemochromatosis is a heterogeneous disorder of iron metabolism characterized by hepatic failure and marked iron accumulation in liver and extrahepatic tissues. Autosomal recessive transmission is found in most cases. Neonatal hemochromatosis shares cellular features with the adult disease but is clinically and genetically distinct, the causal gene(s) being presently unknown. We report on a newborn from consanguineous parents who presented with multiple congenital anomalies and neonatal hemochromatosis. The syndrome consisted of intra-uterine growth retardation, intestinal atresia, gallbladder aplasia and diabetes mellitus, and fitted with the diagnosis of Martinez-Frias syndrome, a very rare autosomal recessive phenotype, the gene of which remains to be identified. We suggest that neonatal hemochromatosis may be part of the Martinez-Frias syndrome. Molecular analyses in this and other reported patients with the Martinez-Frias syndrome should shed light on gut development and iron metabolism.

An unusual presentation of a cystic duplication of the sigmoid colon entirely lined with squamous epithelium

Alimentary tract duplications are rare congenital malformations that occur most commonly in the jejunoileal part of the gastrointestinal tract. Management of this pathologic condition is usually drawn up. We report a case of descending colonic communicating duplication in which clinical presentation and anatomopathologic results were unexpected. A slightly echogenic abdominal mass reaching 72 x 36 mm in the left flank was diagnosed in a female fetus during the third trimester ultrasound examination. At birth, volume of the mass rapidly evolved, and despite no intestinal obstruction was observed by compression of the adjacent gastrointestinal tract, abdomen was distended. Abdominal plain film showed a large air collection, and the barium enema demonstrated a slight leak of contrast in the aerated mass, suggesting a communication with the sigmoid colon. No other abnormalities were seen. The patient underwent surgery in emergency. The mass was then totally excised through an antimesenteric resection of the tubular tract joining cystic mass and sigmoid colon. A lateral suture of the colon was subsequently performed. The wall of the duplication is usually composed of a smooth muscle layer covered by an epithelium, mostly of intestinal type. Herein, we describe a descending colonic duplication completely lined with nonkeratinizing squamous epithelium. Therefore, the association of a colonic mucosa (of endodermic origin) and a squamous epithelium (derived from the ectoderm) in our case is an interesting finding and is not explained by the various theories. Furthermore, the clinical characteristics, diagnosis, and treatment of intestinal duplications are discussed with regard to literature.

Primary microcephaly with ASPM mutation shows simplified cortical gyration with antero-posterior gradient pre- and post-natally

Primary microcephaly is a disorder of brain development characterized by a congenitally small but normally formed brain, and non-progressive mild-to-moderate mental retardation. Most cases are inherited in an autosomal recessive pattern, with genetic heterogeneity, the ASPM locus being most common. Postnatal imaging data are scarce and prenatal imaging unreported. Microcephaly with simplified gyral pattern shares features with primary microcephaly, but it is not clear whether these disorders are part of a phenotypic continuum. We examined a consanguineous family with a daughter affected with primary microcephaly and an ongoing pregnancy. We performed prenatal and postnatal brain magnetic resonance imaging and genetic analyses in the course of genetic evaluation. The affected daughter and the fetus were homozygous for polymorphic markers linked to the ASPM locus, and we identified a novel, truncating ASPM mutation by direct sequencing of the gene. Imaging at 30 and 35 gestational weeks showed microcephaly with simplified gyration, more severe anteriorly. The antero-posterior gradient of gyration persisted 1 week after birth. Brain imaging in the affected sister also showed some degree of a predominantly anterior simplification of gyration. Our data suggest that one form of autosomal recessive microcephaly is allelic to at least a subset of microcephaly with simplified gyral pattern, and that the neuronal depletion associated with the ASPM defect predominantly affects the anterior cortex.

Fetal intracranial tumors: a review of 27 cases

Fetal intracranial tumors are rare. The diagnosis is generally made on histology after birth. The aim of this study was to analyze clinical and imaging data in a series of fetal intracranial tumors and emphasize the findings that may help approach the diagnosis antenatally. We retrospectively analyzed imaging and clinical findings in 27 cases of fetal intracranial tumors assessed by ultrasound (27/27) and MR imaging (24/27). A histological diagnosis was always obtained. Main diagnoses included 15 germinal tumors (13 teratomas), 4 glial tumors, 2 craniopharyngiomas and 3 hamartomas. Average gestational age at diagnosis was 27 weeks for teratomas, 21 weeks for hamartomas and 34 weeks for glial tumors. All tumors but one were supra tentorial, and the lesion extended in the posterior fossa in two teratomas. A heterogeneous pattern, which was more frequently seen in teratomas, was better visualized by MR than US imaging. In addition, in two cases of teratomas, MR imaging better assessed the extension of the tumor. Teratomas and gliomas are the most frequent brain tumors in the fetus. US and MR imagings appear complementary in the prenatal assessment of these lesions.

Management of congenital and posttraumatic splenic cysts in children

Splenic cysts are rarely observed in young patients. We report three cases of splenic cysts. The management and the surgical procedure, if needed, are discussed. If the splenic cyst is symptomatic or if its size reaches a diameter of 4-6cm, it requires surgical management. This treatment would be performed by laparoscopic approach and is intended to spare splenic tissue as much as possible. A prophylactic anti-pneumococcal vaccination is recommended before surgical treatment.

In utero urinary bladder rupture: a case report

We report a case of foetal urinary bladder rupture due to posterior urethral valves. A megacystis was diagnosed in a male foetus during routine second trimester ultrasound examination. The diagnosis of bladder rupture was made as, one week later, the bladder became undetectable with the appearance of ascites. During the follow-up, no oligohydramnios developed and intercurrent ascites resolved spontaneously. There are three described mechanisms releasing bladder hyperpressure: bladder diverticles, unilateral vesicoureteral reflux and bladder rupture. In this case, another mechanism might be involved: a patent urachus. The urethral valves were resected and no other surgical treatment was needed. The renal function remained normal. No long-term vesical follow-up of this pathology is available in the literature.

Contribution of three-dimensional computed tomography in the assessment of fetal skeletal dysplasia

OBJECTIVE

To compare the diagnostic accuracy of two-dimensional (2D) ultrasound and three-dimensional (3D) computed tomography (CT) for the diagnosis of fetal skeletal anomalies.

METHODS

Eleven pregnant women underwent 2D ultrasound and 3D-CT. Ten fetuses presented skeletal anomalies on 2D ultrasound and one fetus had a normal ultrasound exam but a familial history of osteopetrosis. We compared retrospectively the diagnoses established on 2D ultrasound and 3D-CT with the neonatal and/or postmortem work-up, which were used as the gold standard.

RESULTS

2D ultrasound provided the correct diagnosis in only two of the 11 cases. CT yielded the correct diagnosis in eight; in six of these, 2D ultrasound had been inconclusive. 3D-CT was more accurate than was 2D ultrasound in visualizing vertebral anomalies (abnormal shape of the vertebral bodies, abnormal interpedicular distance), pelvic bone malformations (delayed ossification of the pubic bones, abnormal acetabular shape) and enlarged metaphysis or synostoses in long bones. In three cases, neither 2D ultrasound nor CT provided the correct diagnosis.

CONCLUSION

In this series, which included a variety of skeletal dysplasias, 3D-CT had a better diagnostic yield than did 2D ultrasound. Both imaging techniques are useful in the management of fetal dysplasia; 2D ultrasound is a useful screening test and 3D-CT is a valuable complementary diagnostic tool.

Perineal lipoma in a newborn boy--a case report

We report the case of a newborn presenting with a pediculated mass arising from the anal margin. Antenatal sonogram and magnetic resonance imaging were unable to diagnose the precise nature of the lesion. Sacrococcygeal teratoma, an enterogenous cyst, a polyp, a prolapse or other perineal tumors were all proposed as possible entities. At birth, no other anatomic anomaly than this homogenous 2 cm para-anal lesion was seen. Excision of the mass was performed under general anesthesia. The postoperative histological exam showed mature fat cells. Reviewing the literature, there have been few previously reported cases of congenital perineal lipoma. It is a rare, benign and easy-to-treat condition that can be evocated by morphological sonography or magnetic resonance imaging (MRI).

Differential diagnosis of fetal hyperechogenic cystic kidneys unrelated to renal tract anomalies: A multicenter study

OBJECTIVES

To identify important factors in the differential diagnosis of renal cysts associated with hyperechogenic kidneys.

METHODS

This was a retrospective multicenter study. We identified 93 fetuses presenting between 1990 and 2002 with hyperechogenic kidneys and which had a diagnosis of nephropathy confirmed later. We analyzed retrospectively the prenatal ultrasound findings of those fetuses which were found sonographically to have renal cysts.

RESULTS

Of the 93 fetuses presenting with hyperechogenic kidneys and with a later diagnosis of nephropathy, there were 28 with autosomal dominant polycystic kidney disease (ADPKD), 31 with autosomal recessive polycystic kidney disease (ARPKD), 11 with Bardet-Biedl syndrome, nine with Meckel-Gruber syndrome, six with Ivemark II syndrome, one with Jarcho-Levin syndrome, one with Beemer syndrome and one with Meckel-like syndrome. One third of the fetuses (30/93) had renal cysts. Cystic characteristics (size, location, number) were not very useful for diagnosis; more useful was diagnosis of an associated malformation. Three (11%) of the fetuses with ADPKD had cysts, as did nine (29%) of those with ARPKD, three (27%) of those with Bardet-Biedl syndrome, all (100%) of those with Meckel-Gruber syndrome, three (50%) of those with Ivemark II syndrome, and each of the three cases with other syndromes (Jarcho-Levin, Beemer and Meckel-like syndromes). None of the cases with trisomy 13 had cysts. There were no associated malformations in the 12 cases with renal cysts and polycystic kidney disease; the other 18 cases with renal cysts were associated with malformations that were often specific, such as polydactyly in Bardet-Biedl and Beemer syndromes, occipital defect and Dandy-Walker malformation in Meckel-Gruber or Meckel-Gruber-like syndromes, and thoracic and/or vertebral abnormalities in Jarcho-Levin and Beemer syndromes.

CONCLUSION

Renal cysts associated with hyperechogenic kidneys are not rare. The clue to diagnosis is the demonstration of an associated malformation. If no malformation is found, the main diagnosis remains polycystic kidney disease, i.e. ARPKD or ADPKD.

Evolution of fetal ultrasonography

The authors wish to highlight the evolution that has occurred in fetal ultrasound in recent years. A first significant evolution lies in the increasing contribution of first trimester ultrasound for the detection of fetal anomalies. Malformations of several organs and systems have been diagnosed during the first trimester. Furthermore the systematic measurement of the fetal neck translucency has led to increasing rate of detection of aneuploidies and heart malformations. For several years now, three-dimensional (3D) and 4D ultrasound (US) have been used as a complementary tool to 2D US for the evaluation of fetal morphology. This brings an improved morphologic assessment of the fetus. Applications of the techniques are increasing, especially for the fetal face, heart and extremities. The third field where fetal US is continuously providing important information is the knowledge of the natural history of diseases. This has brought significant improvement in the postnatal management of several diseases, especially urinary tract dilatation and broncho-pulmonary malformation.

Perinatal assessment of hereditary cystic renal diseases: the contribution of sonography

The aims of this review article were to clarify the steps that may lead to a proper diagnosis of fetal and neonatal renal cystic diseases. All the hereditary cystic diseases are reviewed and a classification is proposed. The various sonographic patterns that can be used to ascertain the diagnosis are also reviewed. Finally, tables with differential diagnoses are presented to help the reader in the work-up of such pathologies.

Sonographic prenatal diagnosis of malpositioned stomach as a feature of uncomplicated intestinal malrotation

Intestinal malrotation is a developmental anomaly affecting the position and peritoneal attachments of the small and large intestines during fetal life. Most often the diagnosis is established in the first year of life on the basis of abdominal pain and bile-stained vomiting secondary to bowel obstruction. The antenatal diagnosis can be suggested by identification of the complications such as bowel dilatation, ascites or meconium peritonitis. We describe two cases of isolated antenatal gastric malposition without any other associated anomaly that were confirmed after birth to be due to intestinal malrotation. We suggest that such an antenatal finding should alert the paediatrician to close clinical follow-up and prompt the diagnosis and surgical treatment in case of abdominal pain and/or bilious vomiting.