Prenatal Imaging Studies Research Articles

First case report of caudal regression syndrome in a Syrian patient with unusual clinical presentation

Agenesis of the sacrum, lumbar and thoracic vertebrae, is a congenital malformation, associated with other complex genetic syndromes. Sacral agenesis is the partial, or total absence of lower vertebral bodies, can occur isolated or in association with other syndromes including spinal cord anomaly such as (VACTREL syndrome, and Currarino triad).1 The incidence of sacral agenesis is 1/50 000 in general population but is 200 times more frequent in infants of diabetic mothers.2 Usually, children with sacral agenesis have dysmorphic features; to note that around 20% of the cases are undetected until the age of 3- 4 years old and many are diagnosed after unsuccessful toilet training. One of the rarest congenital disorders is “Caudal regression syndrome” that affects the distal spinal segments and result in sequelae on the development of the spinal cord. This syndrome has a low incidence in general population, it is characterized by lower limbs deformities with sensory and motor loss, along with neurogenic bladder however, intelligence is conserved. The exact etiology is vague, yet there is an obvious relation with maternal diabetes. Also, the true cause is still unknown, some theories, state the role of genetic factors, hypoperfusion, and teratogens in the pathogenesis of this syndrome. Treatment is mostly supportive, and multidisciplinary. Prenatal imaging studies allow for consistent detection and diagnosis. The physical exam and the diagnostic test required in the newborn period help in the detection of probable complications and establishing a prognosis. We present a clinical case of a girl with a diagnosis of Caudal regression syndrome, describing the workup and management of this patient.

Absence of Ductus Venosus: A Comparison of 2 Distinctive Fetal Autopsy Cases and Embryologic Perspectives.

In fetal circulation, oxygenated blood from the placenta flows through the umbilical vein into the ductus venosus (DV), then enters the inferior vena cava, and subsequently reaches the right atrium of the heart. The DV serves as a shunt, allowing this oxygen-rich blood to bypass the liver. The absence of the DV (ADV), also known as agenesis of the DV, is a rare congenital anomaly. Without a DV, blood from the umbilical vein must follow alternative routes to the heart. In ADV cases, blood from the umbilical vein must follow 1 of 2 primary drainage patterns: either an extrahepatic shunt or an intrahepatic shunt. This report details the antenatal ultrasound and postmortem findings of 2 fetuses diagnosed with ADV by prenatal imaging studies. The first case involved a fetus with a persistent right umbilical vein connected directly to the suprahepatic IVC, accompanied by early obliteration of the left umbilical vein and true agenesis of the DV. This fetus also had additional congenital anomalies. In contrast, the second case involved a fetus with a normal left umbilical vein that entered the liver. However, despite an ultrasound diagnosis of "absence" of the DV, a DV was present, though markedly hypoplastic and probably minimally functional or non-functional. In this case, blood from the umbilical vein likely followed an alternate intrahepatic route through the portal and hepatic veins, before reaching the heart (intrahepatic shunt). These contrasting cases emphasize the heterogeneity of vascular anomalies and embryologic origins captured by the term "ADV." Additionally, the terminology of "absence" or "agenesis" may be misleading in some purported ADV cases. Specifically, in the second case, the DV was not absent; it was markedly hypoplastic instead. This also appears to be the first reported case of a hypoplastic DV in a fetus. Both cases underscore the importance of effective collaboration and clear communication between maternal-fetal medicine specialists and pathologists.

Prenatal radiographic evaluation of congenital transverse limb deficiencies: A scoping review.

Congenital transverse deficiencies are horizontal deficiencies of the long bones that occur with a reported incidence as high 0.38%. They can occur alone or represent a manifestation of a various clinical syndromes. Diagnosis has traditionally comprised of conventional radiography and prenatal imaging studies. There has been much advancement regarding prenatal imaging modalities to allow for early diagnosis and appropriate treatment. To summarize the current state of knowledge on congenital transverse limb deficiencies and to provide an update regarding the radiographic evaluation of congenital transverse limb deficiencies. This IRB-exempt scoping review followed the PRISMA-ScR checklist for scoping reviews strictly. Five search engines were searched for a total of 265 publications. Four authors reviewed these during the screening process. Of these, 51 studies were included in our article. Prenatal magnetic resonance imaging (MRI), 3D Ultrasound, and multidetector Computed tomography (CT) exist are emerging modalities that have the potential to improve diagnosis. Use of the appropriate classification system, three-dimensional ultrasonography with a maximum intensity projection, and appropriate use of prenatal MRI and prenatal CT can improve diagnosis and inter-provider communication. Further scholarly efforts are required to develop improve standardized guidelines regarding the pre-natal radiographic evaluation of congenital limb deficiencies.

Morphology and Histogenesis of Thymus as a Tool for Estimating Foetal Age: A Cross-sectional Study

Introduction: The thymus is located in the superior mediastinum and anterior part of the inferior mediastinum. It plays a crucial role in the development, differentiation, and clonal expansion of T lymphocytes. In forensic cases involving foetal death, accurate estimation of foetal age is essential. When the foetus is extensively damaged, other organs can be used to estimate age. The thymus, being retrosternal and well-protected, is easily accessible during dissection. Therefore, studying the gross features and histogenesis of the thymus can be helpful in estimating gestational age in cases of severely mutilated foetal specimens. Aim: To examine the morphological features and histogenesis of the thymus in aborted and stillborn foetuses from normal pregnancies. Materials and Methods: A pilot study was conducted using a cross-sectional design at the Department of Anatomy, BLDEDU’s Shri BM Patil Medical College, Vijayapura, Karnataka, India, from May 2016 to April 2018. The dimensions and histogenesis of the thymus were studied in a total of 50 human foetal thymus specimens, collected from normal pregnancies across different gestational age groups ranging from 12 to 40 weeks. The specimens were obtained from the Department of Pathology and the Department of Obstetrics and Gynaecology. The dimensions and weight of the thymus were recorded during autopsy. Slides were prepared, stained with Haematoxylin and Eosin (H&E), and examined under a compound microscope. The histogenesis of the thymus was studied to observe its maturation. Results: Foetal weight increased from 134.6±58.3 g at 12 weeks to 1942±598 g at 40 weeks. The weight of the thymus ranged from 0.2 g at 12 weeks to 5.9 g at 40 weeks. Crown rump length varied from 10.7 cm to 29.9 cm. The length of the thymus measured between 0.5 cm and 3.3 cm, breadth between 0.4 cm and 2.3 cm, and height between 0.2 cm and 0.9 cm from 12 to 40 weeks of gestation. Microscopic features observed in the present study at different gestational ages included a well-formed thick capsule at 17 weeks, lobulation starting at 19 weeks, cortico-medullary differentiation beginning at 17 weeks, appearance of epithelial cells around 19 weeks, and initial appearance of Hassal’s corpuscles at 17 weeks, with more numbers observed later on. Conclusion: The thymus can be used in forensic investigations to estimate the gestational age of mutilated foetuses. It exhibits varying features at different gestational ages, which can aid in thymectomy procedures. Additionally, these findings can be considered during prenatal imaging studies.

Autosomal recessive polycystic kidney disease (ARPKD) in fetus: Autopsy based approach

Polycystic kidney disease is a rare developmental anomaly inherited as Autosomal dominant or recessive. Autosomal recessive polycystic kidney disease (ARPKD) is an intractable cystic renal disease that results in chronic renal failure. It has a profound effect on growing fetus and result in serious implications if pregnancy is continued in the long run after being detected on sonography. Although prenatal imaging studies and clinical findings are suggestive of ARPKD it can be accurately diagnosed by histopathology if an autopsy is performed in cases of infant death. In this article we here in present the features of ARPKD diagnosed antenatally by USG in a 22 yr female, and was confirmed further by fetal autopsy.

Placenta Accreta Spectrum Prenatal Diagnosis Performance: Are Ultrasound False-positive Results Acceptable in Limited-resources Settings?

The immediate referral of patients with risk factors for placenta accreta spectrum (PAS) to specialized centers is recommended, thus favoring an early diagnosis and an interdisciplinary management. However, diagnostic errors are frequent, even in referral centers (RCs). We sought to evaluate the performance of the prenatal diagnosis for PAS in a Latin American hospital. A retrospective descriptive study including patients referred due to the suspicion of PAS was conducted. Data from the prenatal imaging studies were compared with the final diagnoses (intraoperative and/or histological). A total of 162 patients were included in the present study. The median gestational age at the time of the first PAS suspicious ultrasound was 29 weeks, but patients arrived at the PAS RC at 34 weeks. The frequency of false-positive results at referring hospitals was 68.5%. Sixty-nine patients underwent surgery based on the suspicion of PAS at 35 weeks, and there was a 28.9% false-positive rate at the RC. In 93 patients, the diagnosis of PAS was ruled out at the RC, with a 2.1% false-negative frequency. The prenatal diagnosis of PAS is better at the RC. However, even in these centers, false-positive results are common; therefore, the intraoperative confirmation of the diagnosis of PAS is essential.

Prenatal imaging for the diagnosis of congenital Zika syndrome

Abstract Introduction: We aim to synthesize the best available evidence on the accuracy of prenatal imaging for the diagnosis of congenital Zika syndrome due to maternal Zika virus (ZIKV) infection. Specifically, we explored the factors that may influence diagnosis accuracy, such as geographic area, endemicity of ZIKA, operator, gestational age, and type of reference standard used. Methods and analysis Study selection criteria: All types of observational studies were included, that examined pregnant women with ZIKV infection (positive real time polymerase chain reaction or immunoglobulin M (IgM) serological tests and plaque neutralization reduction test). The index tests included prenatal imaging studies (ultrasound and/or magnetic resonance imaging). The reference standard was defined as follows: 1) perinatal death, including stillbirth and neonatal death within the first 48 h of birth, 2) neonatal intensive care unit admission, and 3) composite adverse perinatal outcomes. Case reports will be excluded if they only included fewer than five case. Sources of information: PubMed, Scopus, ISI Web of Science, and Google Scholar will be search from inception to March 2021. Two researchers will independently screen study titles and abstracts for eligibility, followed by full-text assessment. Data extraction will include population, settings, timing, and use of the index test and reference standard used. We will assess the methodological quality of the included studies and a meta-analysis will be performed to estimate summary statistics. Bivariate and hierarchical summary receiver operating characteristic modeling will be used to evaluate the diagnostic performance. The quality of evidence will be assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) metholody. Sources: This systematic review is funded by Secretaria Nacional de Ciencia y Tecnología-Panama. Ethics and dissemination: Ethical approval will not be necessary. Results will be published in a peer review scientific journal. Systematic review registration number in Prospero: CRD42020162914

Fetal and neonatal brain lesions following laser ablation for twin‐to‐twin‐transfusion‐syndrome as detected by pre‐ and post‐natal brain imaging

To determine the rate of and risk factors for fetal and neonatal brain lesions following laser ablation for twin-to-twin transfusion syndrome (TTTS). A retrospective cohort study of 83 women with monochorionic twin pregnancies who underwent ablation for TTTS at a single tertiary hospital. Post-laser survivors were followed-up with fetal neurosonogram every 2weeks and fetal brain MRI at 28-32weeks of gestation; post-natal brain imaging included neurosonogram. Cases with pre- and post-natal brain lesions were compared to those without. 153 fetuses survived the immediate post-laser period and underwent brain imaging. Of these, 17 (11.11%) exhibited brain lesions on prenatal imaging studies, and 36 (32.4%) on post-natal ultrasound. Later gestational age (GA) at the time of ablation (23.0 vs. 21.4weeks, p=0.0244), post-laser twin-anemia-polycythemia-sequence (TAPS) (29.41% vs. 9.56%, p=0.035) and birthweight discordancy (30% vs. 9%, p=0.0025) were associated with prenatal brain lesions. Earlier GA at delivery (31.0weeks vs. 32.2, p=0.0002) and post-laser TAPS (25% vs. 9.33%, p=0.038) were associated with post-natal brain lesions. Survivors of ablation for TTTS are at risk for brain lesions, which can be detected prenatally. Incorporation of neurosonogram and fetal brain MRI into the routine surveillance of such pregnancies should be considered.

416 Prenatal diagnosis performance of the spectrum of placenta accreta, the cost of safety

The spectrum of placenta accreta (PAS) causes severe morbidity. Diagnosis errors in US and MRI are frequent, with false positives and negatives in a third of cases. We aim to describe the performance of prenatal images (at initial diagnosis center -IDC-) made before PAS patients arrived at a specialized hospital and the results of the reevaluation by a expert group in a referral center (RC) We conducted a retrospective, descriptive study, including referred patients with suspected PAS to a RC in Colombia, between December 2016 and July 2020. We evaluate prenatal imaging studies performed since the suspected diagnosis of PAS, before and after contact with the RC, and its results were compared with the final diagnosis (intraoperative and/or histological). 125 patients were included (Image 1), 56 patients were taken to surgery on suspicion of PAS at 35 weeks (Group 1), 44 of these patients had a repeated prenatal image. In group 1, 38 women had final diagnosis of PAS. In the remaining 18, the final diagnosis was placenta previa, normal placenta or uterine rupture; in 7 of these cases, it was not possible to perform prenatal imaging due to requiring emergent surgery. In 69 patients the diagnosis of PAS was ruled out by prenatal image at RC (Group 2). These pregnancies were ended in week 36, with a final diagnosis of PAS in 2 of them. The frequency of false positives (FP) comparing the initial diagnosis (at IDC) with RC diagnosis was 55.2%. Comparing the “working diagnosis” at the RC (the presumptive diagnosis with which the surgery begins) with the “final diagnosis”, 14.2% of the patients managed as affected by PAS had another diagnosis (RC FP) and 2.9% of the patients had an unsuspected intraoperative finding of PAS (RC false negatives) Prenatal screening for PAS has a better performance at RC. The occurrence of FP is an acceptable situation given the great burden of morbidity of an unsuspected PAS (it is the “cost of safety”).

Pathologist's role in identifying cardiac defects—a fetal autopsy series

AimsMajor cardiac abnormalities can lead to miscarriages and is also an important indication of medical termination of pregnancy. The present study aims: (1) To determine the spectrum of cardiac anomalies in fetal autopsies, (2) To correlate the autopsy findings with prenatal imaging studies. MethodsFetal autopsies with cardiac anomalies were retrospectively analyzed over a period of five years. Autopsy diagnoses were correlated with prenatal ultrasound and echocardiogram findings. ResultsOf the 177 fetal autopsies, 40 (22.5%) cases with cardiac defects were identified. Among these cases, 11 (27.5%) showed only cardiac defects and associated extracardiac malformations were seen in 29 cases (72.5%). Septal defects (45%) were the most frequent cardiac defect followed by left ventricular outflow tract obstruction. Agreement with prenatal imaging and autopsy findings was seen in 65% of cases. There was 100% concordance between autopsy and echocardiogram wherever available. ConclusionCardiac malformation forms a significant subset of fetal congenital anomalies. Meticulous examination and following sequential segmental analysis during autopsy are essential in identifying complex cardiac and additional extra cardiac defects in the fetuses. Fetal autopsy plays a vital role in confirming and/or refuting the imaging findings and could be the steppingstone in understanding the pathogenesis of cardiac abnormalities.

Correlation of Prenatal Diagnosis and Pathology Findings Following Dilation and Evacuation for Fetal Anomalies

-Despite increased use of dilation and evacuation in the setting of fetuses with developmental anomalies, the pathology examination of fragmented specimens obtained by this technique has been understudied. -To correlate pathologic findings in second-trimester fetal dilation and evacuation specimens with prenatal diagnoses established through ultrasound and/or chromosome studies to determine the value of pathology examination for supplementing or correcting clinical diagnoses. -In this retrospective study, clinical and pathology findings were correlated in 448 dilation and evacuation specimens performed for second-trimester termination of pregnancy for fetal anomalies discovered on ultrasound examination (278 cases) or chromosome analysis (170 cases). -In 109 of the 170 cases with chromosomal abnormalities (64%), pathologists identified at least 1 congenital defect associated with the respective karyotype. In 278 cases with ultrasound-detected anomalies, pathologists confirmed the major congenital defect in 116 fetal specimens (42%). Evaluating for congenital central nervous system and body wall/diaphragm pathologic findings proved challenging owing to tissue disruption. However, taking all categories into account, pathology studies corrected ultrasound diagnoses in 152 of 413 cases (37%) and yielded additional diagnostic findings in 137 cases (33%). -In a substantial number of cases, examination of fragmented fetuses corrected or refined prenatal diagnoses, demonstrating a role for detailed pathology examination of dilation and evacuation specimens in quality control of prenatal imaging studies and for potentially aiding subsequent genetic counseling.

Congenital Diaphragmatic Hernia with Delayed Diagnosis: Report of Two Cases

Introduction: Advances in prenatal imaging studies have allowed early diagnosis of Congenital Diaphragmatic Hernia (CDH), although neonatal mortality remains at high levels (60% survival). Despite advances, this study found delayed diagnosis, demonstrating subdiagnosis, possibly caused by lack of resources and/or prenatal diagnostic failure. Case Report 1: Infant, 4 months and 22 days old, dyspneic, cyanotic, with fever and vomiting for 3 days, treated as pneumonia. After the second chest radiography, a right CDH was revealed. Surgical correction was performed and removal of Meckel’s diverticulum was surgical findings. The patient was discharged on the 10th days after admission. Case Report 2: Infant, 11 months and 3 days old, distended abdomen, with fever and dyspnea for 2 days, treated as pneumonia. After the second chest radiography, a left CDH was revealed. The patient was submitted to surgery, intestinal loop incarceration without necrosis was observed, and the correction of CDH was performed. The patient was discharged on the 7th day after admission. Discussion: Three cases, between July 2012 and July 2013, were diagnosed at Dom Malam Hospital; 2 Cases of CDH, with delayed diagnosis, showed incidence of 66.66%. Delayed diagnosis of these patients with initial hypotheses of pneumonia demonstrated high risk, emphasizing the importance of diagnosis research through observation of the clinical course, the correct imaging interpretation, in order to establish early diagnosis and treatment.

Statistical Analysis and Interpretation of Prenatal Diagnostic Imaging Studies, Part 1

Screening and diagnostic testing play fundamental roles in all fields of clinical medicine, with obstetric imaging and prenatal diagnosis being no exceptions. With advances in maternal serum screening and ultrasound technology, much research effort in the field of pre-natal diagnosis has actually been dedicated to the development and refinement of screening tests for fetal aneuploidy and other congenital disorders. This article aims to review the differences between screening and diagnostic tests, describe the accepted criteria for an efficient screening test, and provide an overview of the calculation and interpretation of test performance characteristics in relation to prenatal imaging studies.

Pulmonary vascular malformations

Pulmonary vascular malformations have historically been diagnosed in a wide range of age groups, but the extensive use of prenatal imaging studies has resulted in the majority of lesions being diagnosed in utero. Among this group of lesions, bronchopulmonary sequestrations (BPS), hybrid lesions with both congenital cystic adenomatoid malformation (CCAM) and BPS, aberrant systemic vascular anastomoses, and pulmonary arteriovenous malformations (PAVM), are the most common. The biologic behavior of these lesions and the subsequent therapy is, in large part, determined by the age of the patient at diagnosis. In the fetus, large BPS or hybrid lesions can result in fetal hydrops and in utero fetal demise. In the perinatal period, pulmonary hypoplasia from the mass effect or air trapping within the cystic component of hybrid lesions can result in life-threatening respiratory distress. In the postnatal period, communication of the lesion with the aero-digestive system can result in recurrent pneumonia. Alternatively, increased pulmonary blood flow from the systemic arterial supply can result in hemorrhage, hemoptysis, or high output cardiac failure. In addition, there have been several reports of malignant degeneration. Finally, the broad spectrum encompassed by these lesions makes classification and subsequent communication of the lesions confusing and difficult. This paper will review the components of these lesions, their associated anomalies, the diagnosis and natural history, and finally, current concepts in the management of pulmonary vascular malformations.

Prenatal magnetic resonance imaging in Gomez‐Lopez‐Hernandez syndrome and review of the literature

Gomez-Lopez-Hernandez syndrome, or cerebello-trigeminal-dermal dysplasia (OMIM#601853), is a rare syndrome comprising cerebellar abnormalities, parieto-occipital alopecia, trigeminal nerve anesthesia, intellectual impairment, craniosynostosis, short stature, and craniofacial anomalies. It has been reported in ten patients, five of whom are Brazilian. Rhombencephalosynapsis is a rare sporadic cerebellar anomaly comprising fusion of the cerebellar hemispheres with agenesis of the cerebellar vermis. Rhombencephalosynapsis is a constant feature of Gomez-Lopez-Hernandez syndrome. We present the clinical and imaging findings of a Caucasian male infant with Gomez-Lopez-Hernandez syndrome. Rhombencephalosynapsis was diagnosed with fetal magnetic resonance imaging (MRI) after an abnormally shaped small cerebellum was detected by antenatal ultrasound (US). Gomez-Lopez-Hernandez syndrome was diagnosed at age 6 weeks when parietal alopecia was noted. Prenatal imaging studies of Gomez-Lopez-Hernandez syndrome have not been published before. When rhombencephalosynapsis is diagnosed prenatally, the clinical features of Gomez-Lopez-Hernandez syndrome should be sought at postnatal review. Gomez-Lopez-Hernandez syndrome and isolated rhombencephalosynapsis may have a common etiology.

Increased Renal Echogenicity: A Sonographic Sign for Differentiating Between Obstructive and Nonobstructive Etiologies of in Utero Bladder Distension

Purpose The combination of in utero bladder distension and bilateral hydroureteronephrosis in male fetuses may result from a number of pathological processes. The prenatal and postnatal treatment of patients with an enlarged bladder is dictated by the specific etiology leading to these changes. We propose specific ultrasonographic criteria for differentiating between obstructive and nonobstructive etiologies in these fetuses. Materials and Methods We reviewed the medical records and prenatal imaging studies of 18 cases of marked in utero bladder distension in which a diagnosis of posterior urethral valves, the megacystis-megaureter association or the prune-belly syndrome was confirmed postnatally. Amniotic fluid volume and renal echogenicity were assessed before knowledge of the specific diagnosis. Oligohydramnios was graded as mild, moderate or severe. Increased renal echogenicity was defined as greater echogenicity of the renal cortex and/or medulla than of adjacent liver tissue. Postnatal imaging, clinical course and outcome were also reviewed. Results The study included 15 cases with adequate followup, including 8 in which a diagnosis of posterior urethral valves was confirmed postnatally. Nonobstructive etiologies included the megacystis-megaureter association in 6 cases and the prune-belly syndrome in 1. Seven of the 8 patients with posterior urethral valves had moderate to severe oligohydramnios, whereas all but 1 with a nonobstructive etiology had normal amniotic fluid. Seven of the 8 cases with posterior urethral valves had a marked bilateral increase in renal echogenicity, while none of the nonobstructive cases had this finding. Conclusions Increased renal echogenicity and oligohydramnios in the setting of bladder distension are highly predictive (87%) of an obstructive etiology. This finding is important in the prenatal counseling and treatment of boys with bilateral hydronephrosis and marked bladder dilatation.