A clinical algorithm of prenatal diagnosis of Radial Ray Defects with two and three dimensional ultrasound

Fetal Hands: A Comprehensive Review of Prenatal Assessment and Diagnosis Over the Past 40 Years

Fetal skeletal dysplasias involving limbs and hands are rare congenital malformations. Prenatal two-dimensional ultrasound diagnosis of fetal limb defects has a sensitivity of about 30%; however, an increased detection rate may be obtained using three-dimensional (3-D) ultrasound in the rendering mode. 3-D ultrasound may be used as a complementary method providing additional information. Currently, magnetic resonance imaging (MRI), with the emergence of ultrafast imaging techniques and new sequences, allows for better diagnosis of several fetal skeletal dysplasias such as limb reduction defects and neuromuscular disorders. 3-D volumetric images from ultrasound or MRI scan data allow 3-D ultrasound reconstructions of virtual/physical models, and virtual reality can help researchers to improve our understanding of both normal and abnormal fetal limb/hand anatomy. In this article, we review the embryological development of fetal hands and their main anomalies including prenatal diagnostic methods, genetic counseling, the role of orthopedic and plastic surgery reconstruction, and new perspectives in fetal surgery.

Implementation of Exome Sequencing in Prenatal Diagnostics: Chances and Challenges

Whole exome sequencing (WES) has become part of the postnatal diagnostic work-up of both pediatric and adult patients with a range of disorders. In the last years, WES is slowly being implemented in the prenatal setting as well, although some hurdles remain, such as quantity and quality of input material, minimizing turn-around times, and ensuring consistent interpretation and reporting of variants. We present the results of 1 year of prenatal WES in a single genetic center. Twenty-eight fetus-parent trios were analyzed, of which seven (25%) showed a pathogenic or likely pathogenic variant that explained the fetal phenotype. Autosomal recessive (4), de novo (2) and dominantly inherited (1) mutations were detected. Prenatal rapid WES allows for a timely decision-making in the current pregnancy, adequate counseling with the possibility of preimplantation or prenatal genetic testing in future pregnancies and screening of the extended family. With a diagnostic yield in selected cases of 25% and a turn-around time under 4 weeks, rapid WES shows promise for becoming part of pregnancy care in fetuses with ultrasound anomalies in whom chromosomal microarray did not uncover the cause.

Upper limb phocomelia: A prenatal case of thrombocytopenia-absent radius (TAR) syndrome illustrating the importance of chromosomal microarray in limb reduction defects

OBJECTIVE

To describe the ultrasonographic, pathologic and molecular findings in a fetus with TAR syndrome, and to illustrate the contribution of chromosomal microarray analysis (CMA) to the etiological investigation of fetal upper limb reduction defects.

CASE REPORT

A 35-year-old woman was referred for Genetic Counseling after pregnancy termination for severe upper limb bilateral phocomelia detected in the second trimester. Fetal autopsy showed severe shortening of the arms and forearms. The fetal skeletal survey confirmed the absence of the radii, ulnae and humeri. CMA revealed an interstitial deletion in 1q21 including the RBM8A gene. Subsequent Sanger sequencing of this gene identified a hypomorphic mutant allele, c.-21G > A, confirming the diagnosis of TAR syndrome.

CONCLUSION

The differential diagnosis of upper limb defects is broad. Identification of their cause is essential for adequate genetic counseling including prognosis and recurrence risk estimation. CMA should be considered in fetuses with upper limb reduction defects, especially when the thumbs are present.

Prenatal diagnosis of radial ray defects by ultrasound: A report of 6 cases

OBJECTIVE

All of the medical records of fetuses with the sonographic finding of radial ray defects (RRDs) between 2008 and 2015 were retrieved. The associated sonographic findings, cytogenetic results, and necropsy findings were correlated.

CASE REPORT

There were 6 cases of RRD. Three cases were bilateral and the other 3 cases were unilateral. The gestational ages at diagnosis were between 12 and 24 weeks gestation. All women carrying fetuses with RRDs opted to terminate the pregnancy. There were 2 cases of trisomy 18, one case of thrombocytopenia-absent radius syndrome, and 2 cases of isolated RRD. Both cases of trisomy 18 had other sonographic abnormalities.

CONCLUSION

RRD should be considered if a short radius and abnormal angulation of the wrist or thumb is noted. The use of 3-D ultrasound facilitates the diagnosis of RRD, even at early gestation, by providing a better surface appearance, panoramic views, and spatial orientation.

Heterogeneous Diagnoses Underlying Radial Ray Anomalies

OBJECTIVE

To review perinatal Radial Ray Anomaly (RRA) cases born at the National Institute of Perinatology, Mexico, and to reveal the heterogeneous diagnoses of these patients.

METHODS

All patients with RRA over a 18 mo period were included; 4/15 were detected prenatally and 11/15 postnatally. Karyotype was performed for all patients with bilateral RRA; and chromosomal breakage analysis, when the karyotype was normal.

RESULTS

Fifteen RRA patients were identified: one with trisomy 18, three with an isolated defect, six with monogenic disease, four with a genetic association and one with diabetic embryopathy. Five were stillborn and two died during the early neonatal period; all of whom presented with multiple defects. Three of the live born patients and one stillborn with multiple defects had Fanconi anemia. RRAs carry a high perinatal mortality rate (47%) when they occur in association with other defects.

CONCLUSIONS

The assessment of these patients needs to involve the combined use of ultrasound, clinical, genetic, cytogenetic and molecular testing. The present results indicate that the chromosome breakage test should always be performed to rule out Fanconi anemia in this group.

Prenatal sonographic diagnosis of fetal valproate syndrome: a case report

BACKGROUND

Prenatal exposure of mother to valproate (VPA) causes teratogenic effects in the fetus, namely fetal valproate syndrome (FVS). We report a case of fetal valproate syndrome rarely diagnosed by prenatal sonographic examination.

CASE PRESENTATION

Our patient was a female infant who was born to a 27-year-old nulliparous Japanese woman with epilepsy. The mother was diagnosed with infantile epilepsy at 1 year of age and had been using three antiepileptic drugs, including valproate, but preconceptional counseling was not performed. At 25 weeks of gestation, contracture of the fetal right wrist joint suggestive of a radial ray defect was observed by transabdominal ultrasonography. The fetus demonstrated growth retardation starting from 32 weeks of gestation. In addition, saddle nose as a facial anomaly was detected by three-dimensional ultrasound at 37 weeks of gestation. Accordingly, we suspected that the fetus had fetal valproate syndrome. At 39 weeks of gestation, the mother delivered an infant weighing 2056 g. The neonate had characteristic features of fetal valproate syndrome, such as facial configuration, slight muscular hypotonia of the whole body, breathing problems, right-hand articular contracture accompanied by radial ray defect, and cardiovascular malformation.

CONCLUSIONS

When obstetricians manage epileptic pregnant women without enough preconceptional counseling or adjustment for antiepileptic drugs, careful sonographic observation of the fetus is mandatory.

Role of Genetic Factors in the Pathogenesis of Radial Deficiencies in Humans

Radial deficiencies (RDs), defined as under/abnormal development or absence of any of the structures of the forearm, radial carpal bones and thumb, occur with a live birth incidence ranging from 1 out of 30,000 to 1 out 6,000 newborns and represent about one third/one fourth of all the congenital upper limb anomalies. About half of radial disorders have a mendelian cause and pattern of inheritance, whereas the remaining half appears sporadic with no known gene involved. In sporadic forms certain anomalies, such as thumb or radial hypoplasia, may occur either alone or in association with systemic conditions, like vertebral abnormalities or renal defects. All the cases with a mendelian inheritance are syndromic forms, which include cardiac defects (in Holt-Oram syndrome), bone marrow failure (in Fanconi anemia), platelet deficiency (in thrombocytopenia-absent-radius syndrome), ocular motility impairment (in Okihiro syndrome). The genetics of radial deficiencies is complex, characterized by genetic heterogeneity and high inter- and intra-familial clinical variability: this review will analyze the etiopathogenesis and the genotype/phenotype correlations of the main radial deficiency disorders in humans.

Prenatal Detection of Upper Limb Differences With Obstetric Ultrasound

PURPOSE

To determine the sensitivity, specificity, and predictive values of prenatal ultrasound detection of fetal upper extremity anomalies at a single tertiary care center in a large patient cohort. Our secondary purpose was to assess factors affecting prenatal detection including the presence of associated anomalies.

METHODS

We performed a retrospective review of prenatal ultrasound and postnatal clinical records from each pregnancy evaluated with a prenatal ultrasound at the Washington University Department of Obstetrics and Gynecology over a 20-year period. We searched for upper extremity anomaly diagnosis codes pre- and postnatally and correlated with clinical postnatal follow-up to determine prevalence, sensitivity, specificity, predictive values, and associated conditions.

RESULTS

A total of 100,856 pregnancies were evaluated by prenatal ultrasound, which included 843 fetuses diagnosed with a musculoskeletal anomaly (prevalence, 1 of 120) and 642 with an upper extremity anomaly (prevalence, 1 of 157). The postnatally confirmed sensitivity for prenatal ultrasound detection of an upper extremity anomaly was 42%. Sensitivity was lower in cases isolated to the upper extremity (25% vs 55%). Sensitivity was highest for conditions affecting the entire upper extremity (70%-100%) and lowest for those affecting the digits alone (4%-19%). Fetuses with limb reduction defects, radial longitudinal deficiency, phocomelia, arthrogryposis, abnormal hand positioning, and cleft hand had a higher likelihood of having an associated anomaly.

CONCLUSIONS

At our tertiary referral center, there was a notable prevalence of upper extremity anomalies; however, the overall sensitivity for detecting them with prenatal ultrasound was low. This was disappointing given the value of prenatal identification of anomalies for parental counseling. Prenatal diagnosis of anomalies affecting the entire upper limb was more reliable than diagnosis of more distal anomalies.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

The utility of ultrasound for the detection of fetal limb abnormalities--a 20-year single-center experience

Objective

The standard obstetric ultrasound examination includes documentation of arms and legs. The purpose of this study is to review the efficacy of ultrasound for the detection of limb anomalies, the type and incidence of associated malformations and pregnancy outcomes.

Method

All cases of polydactyly (POD), abnormal hand position (AHP), limb reduction defects (LRD) and arthrogryposis (ART) scanned in our Unit between 1990 and 2010 were identified. Cases were categorized as isolated (ISO) or non-isolated (NISO). The accuracy of prenatal diagnosis, type and incidence of associated malformations and aneuploidy and pregnancy outcomes were determined.

Results

Most cases were NISO. The sensitivity of ultrasound was 19.1% for POD, 76.0% for AHP, 76.0% for LRD involving the long bones and 81.3% for ART. Cardiothoracic and facial defects were the most common accompanying malformations. The risk for aneuploidy ranged from 3.6% for POD to 47.2% for AHP. The live birth rate ranged from 85.5% for POD to 24.5% for AHP.

Conclusion

While imaging of the arms and legs allows detection of most cases of AHP, LRD involving the limbs and ART, a probable minimum of 20% to 25% of cases will escape prenatal diagnosis. Identification of these defects should prompt an extended anatomic survey and consideration of invasive testing for aneuploidy. © 2014 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd.

The utility of prenatal ultrasound as a screening tool for upper extremity congenital anomalies

PURPOSE

To quantify the detection rate and accuracy of prenatal ultrasound in patients with congenital upper extremity anomalies.

METHODS

A total of 100 patients with congenital upper extremity reduction or duplication anomalies were enrolled prospectively in this investigation at the initial visit to our congenital hand clinic. Demographic and pregnancy-related data were collected along with prenatal diagnoses. We recorded all ultrasound-identified upper extremity anomalies as reported by the parents. Finally, we compared the prenatal diagnosis with the final congenital hand clinic diagnosis.

RESULTS

The first ultrasound was performed at a mean 11 weeks' gestation, and patients underwent an average of 8 prenatal ultrasounds (range, 1-40 prenatal ultrasounds). Sixty patients underwent standard ultrasound and 40 had a 3-dimensional ultrasound as well. Of the 100 patients, 31 had an upper extremity anomaly by ultrasound. Of the 31 prenatal ultrasound diagnoses, 18 were confirmed as accurate during evaluation in the congenital hand clinic. Three-dimensional ultrasound was more sensitive for the detection of upper extremity anomalies.

CONCLUSIONS

The overall detection rate and accuracy of ultrasonography for upper extremity anomalies were low despite advancements in imaging technology.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

A pictorial guide for the second trimester ultrasound

Introduction: The second trimester ultrasound remains an important screening tool for detecting fetal abnormalities. This pictorial guide for the second trimester ultrasound is designed to assist practitioners to produce a high quality diagnostic survey of the fetus by demonstrating and describing recommended images. Methods: Each image is discussed in detail and has an associated drawn line diagram to aid in the identification of the important features of that image. There is a description of the salient landmarks and relevant measurements. Result: The authors hope this article may act as a useful guide to all practitioners performing second trimester ultrasounds.

Prenatal diagnosis of bilateral ectrodactyly and radial agenesis associated with trisomy 10 mosaicism

Ectrodactyly or split hand and foot malformations (SHFMs) are rare malformations of the limbs, characterized by median clefts of the hands and feet, syndactyly, and aplasia and/or hypoplasia of the phalanges. They represent a clinically and genetically heterogeneous disorder, with both sporadic and familial cases. Most of the genomic rearrangements identified to date in some forms of SHFM are autosomal dominant traits, involving various chromosome regions. Bilateral radial ray defects comprise also a large heterogenous group of disorders, including trisomy 18, Fanconi anemia, and thrombocytopenia-absent-radius syndrome, not commonly associated with ectrodactyly. The present paper describes a case of ectrodactyly associated with bilateral radial ray defects, diagnosed in the first trimester of pregnancy, in a fetus affected by trisomy 10. Only four cases of sporadic and isolated ectrodactyly, diagnosed by ultrasonography between 14 and 22 weeks' gestation, have been reported. To our knowledge, the present case is the first report of mosaic trisomy 10 associated with SHFM and radial aplasia. Trisomy 10 is a rare lethal chromosomal abnormality, most frequently found in abortion products. Only six liveborn mosaic trisomy 10 infants, with severe malformations, dead in early infancy, have been reported. A severe clinical syndrome can be defined, comprising ear abnormalities, cleft lip/palate, malformations of eyes, heart, and kidneys, and deformity of hands and feet and most often associated with death neonatally or in early infancy.

Identification of a prenatal profile of Cornelia de Lange syndrome (CdLS): a review of 53 CdLS pregnancies

Cornelia de Lange Syndrome (CdLS) is a multisystem developmental disorder characterized by growth retardation, cognitive impairment, external and internal structural malformations, and characteristic facial features. Currently, there are no definitive prenatal screening measures that lead to the diagnosis of CdLS. In this study, documented prenatal findings in CdLS syndrome were analyzed towards the development of a prenatal profile predictive of CdLS. We reviewed 53 cases of CdLS (29 previously reported and 24 unreported) in which prenatal observations/findings were available. The review of these cases revealed a pattern of sonographic findings, including obvious associated structural defects, growth restriction, as well as a more subtle, but strikingly characteristic, facial profile, and suggestive of a recognizable prenatal ultrasonographic profile for CdLS. In addition, the maternal serum marker, PAPP-A, may be reduced and fetal nuchal translucency (NT) may be increased in some pregnancies when measured at an appropriate gestational age. In conclusion, CdLS can be prenatally diagnosed or readily ruled out in a family with a known mutation in a CdLS gene. The characteristic ultrasonographic profile may allow for prenatal diagnosis of CdLS in (1) subsequent pregnancies to a couple with a prior child with CdLS in whom a mutation has not been identified or (2) when there are unexplained pregnancy signs of fetal abnormality, such as oligo- or polyhydramnios, a low maternal serum PAPP-A level and/or increased NT, fetal growth retardation, or structural anomalies consistent with CdLS.