The value of fetal magnetic resonance imaging in diagnosis of congenital anomalies of the fetal body: a systematic review and meta-analysis.

OBJECTIVES: To undertake a systematic review to assess the accuracy of fetal MRI in diagnosis of non-CNS congenital anomalies of the fetal body in comparison with antenatal ultrasound when correlated to postnatal diagnosis. METHODS: Searches were conducted from electronic databases, key journals and reference lists for eligible papers. Inclusion criteria was original research studies comparing the diagnostic results of antenatal ultrasound, fetal MRI and final postnatal diagnosis via imaging, surgery or post-mortem testing. Studies of CNS anomalies were excluded. Studies were assessed for risk of bias by two reviewers working independently and data was then extracted by a single reviewer. RESULTS: 12 studies were included with a total of 361 eligible patients who underwent USS and MRI and had a postnatal diagnosis. USS alone had a diagnostic accuracy of 60.6% whereas MRI had an improved diagnostic accuracy of 86.4%. The overall odds ratio was 0.86 (CI 0.202-1.519 and p-value < 0.01). CONCLUSION: Fetal MRI makes a significant contribution to accurate diagnosis of congenital abnormalities of the fetal body; especially in genito-urinary anomalies. More research is needed to improve the evidence base for the role of fetal MRI in diagnosis of congenital anomalies in other body systems.

Current and future funding streams for paediatric postmortem imaging: European Society of Paediatric Radiology survey results.

BACKGROUND: Perinatal and childhood postmortem imaging has been accepted as a noninvasive alternative or adjunct to autopsy. However, the variation in funding models from institution to institution is a major factor prohibiting uniform provision of this service. OBJECTIVE: To describe current funding models employed in European and non-European institutions offering paediatric postmortem imaging services and to discuss the perceived barriers to future postmortem imaging service provision. MATERIALS AND METHODS: A web-based 16-question survey was distributed to members of the European Society of Paediatric Radiology (ESPR) and ESPR postmortem imaging task force over a 6-month period (March-August 2021). Survey questions related to the radiologic and autopsy services being offered and how each was funded within the respondent's institute. RESULTS: Eighteen individual responses were received (13/18, 72.2% from Europe). Only one-third of the institutions (6/18, 33.3%) have fully funded postmortem imaging services, with the remainder receiving partial (6/18, 33.3%) or no funding (5/18, 27.8%). Funding (full or partial) was more commonly available for forensic work (13/18, 72%), particularly where this was nationally provided. Where funding was not provided, the imaging and reporting costs were absorbed by the institute. CONCLUSION: Increased access is required for the expansion of postmortem imaging into routine clinical use. This can only be achieved with formal funding on a national level, potentially through health care commissioning and acknowledgement by health care policy makers and pathology services of the value the service provides following the death of a fetus or child. Funding should include the costs involved in training, equipment, reporting and image acquisition.

Computed tomography chest imaging offers no advantage over chest X-ray in the initial assessment of gestational trophoblastic neoplasia.

BACKGROUND: The International Federation of Gynaecology and Obstetrics (FIGO) score identifies gestational trophoblastic neoplasia (GTN) patients as low- or high-risk of single-agent chemotherapy resistance (SACR). Computed tomography (CT) has greater sensitivity than chest X-ray (CXR) in detecting pulmonary metastases, but effects upon outcomes remain unclear. METHODS: Five hundred and eighty-nine patients underwent both CXR and CT during GTN assessment. Treatment decisions were CXR based. The number of metastases, risk scores, and risk category using CXR versus CT were compared. CT-derived chest assessment was evaluated as impact upon treatment decision compared to patient outcome, incidence of SACR, time-to-normal human chorionic gonadotrophin hormone (TNhCG), and primary chemotherapy resistance (PCR). RESULTS: Metastasis detection (p < 0.0001) and FIGO score (p = 0.001) were higher using CT versus CXR. CT would have increased FIGO score in 188 (31.9%), with 43 re-classified from low- to high-risk, of whom 23 (53.5%) received curative single-agent chemotherapy. SACR was higher when score (p = 0.044) or risk group (p < 0.0001) changed. Metastases on CXR (p = 0.019) but not CT (p = 0.088) lengthened TNhCG. Logistic regression analysis found no difference between CXR (area under the curve (AUC) = 0.63) versus CT (AUC = 0.64) in predicting PCR. CONCLUSIONS: CT chest would improve the prediction of SACR, but does not influence overall treatment outcome, TNhCG, or prediction of PCR. Lower radiation doses and cost mean ongoing CXR-based assessment is recommended.

Current state of perinatal postmortem magnetic resonance imaging: European Society of Paediatric Radiology questionnaire-based survey and recommendations.

BACKGROUND: Postmortem magnetic resonance imaging (MRI) in perinatal and childhood deaths is increasingly used as a noninvasive adjunct or alternative to autopsy. Imaging protocols vary between centres and consensus guidelines do not exist. OBJECTIVE: Our aim was to develop practical, standardised recommendations for perinatal postmortem MRI. MATERIALS AND METHODS: Recommendations were based on the results of two surveys regarding local postmortem MRI practices sent electronically to all 14 members of the European Society of Paediatric Radiology (ESPR) Postmortem Imaging Task Force and 17 members of the International Society of Forensic Radiology and Imaging Task Force (25 different centres). RESULTS: Overall, 11/14 (78.6%) respondents from different institutions perform postmortem MRI. All of these centres perform postmortem MRI for perinatal and neonatal deaths, but only 6/11 (54.5%) perform imaging in older children. CONCLUSION: We propose a clinical standard for postmortem MRI sequences plus optional sequences for neuroimaging and cardiac anatomy depending on available scanning time and referral indications.

Benefits and Limitations of the Minimally Invasive Postmortem: A Review of an Innovative Service Development.

INTRODUCTION: Pediatric postmortem (PM) rates have significantly declined, creating a need for effective minimally invasive alternatives to correlate with parental wishes. We review the use of a minimally invasive fetal and neonatal PM service further to preliminary findings published in 2015. MATERIALS AND METHODS: Cases taken from the mortuary electronic database from 2012 to 2017 are analyzed. The minimally invasive service consisted primarily of external examination, magnetic resonance imaging (MRI), and placental examination. Any significant conditions found noted. All pathology reports include a Relevant Condition at Death (ReCoDe) obstetric classification. Reports analyzed to determine which aspects of the service provided positive information. RESULTS: Of 1498 perinatal postmortems, 105 (7%) were PM MRI, of which 75.24% were intrauterine fetal deaths. Relevant conditions were identified in 94 cases (89.52%), and ReCoDe categories in 80 cases (76.19%). Moreover, 90% of cases had a ReCoDe condition, with 10% unclassified. Seven cases had more than 1 ReCoDe. Main conditions related to placenta (32.5%) and umbilical cord (27.5%). The most informative elements were placental examination and MRI. CONCLUSION: Minimally invasive PMs are a viable alternative to traditional autopsy when this option is refused. However, further case analysis is needed to determine potential bias toward certain classification codes.

How to obtain diagnostic planes of the fetal central nervous system using three-dimensional ultrasound and a context-preserving rendering technology.

The antenatal evaluation of the fetal central nervous system (CNS) is among the most difficult tasks of prenatal ultrasound (US), requiring technical skills in relation to ultrasound and image acquisition as well as knowledge of CNS anatomy and how this changes with gestation. According to the International Guidelines for fetal neurosonology, the basic assessment of fetal CNS is most frequently performed on the axial planes, whereas the coronal and sagittal planes are required for the multiplanar evaluation of the CNS within the context of fetal neurosonology. It can be even more technically challenging to obtain "nonaxial" views with 2-dimensional (2D) US. The modality of 3-dimensional (3D) US has been suggested as a panacea to overcome the technical difficulties of achieving nonaxial views. The lack of familiarity of most sonologists with the use of 3D US and its related processing techniques may preclude its use even where it could play an important role in complementing antenatal 2D US assessment. Furthermore, once a 3D volume has been acquired, proprietary software allows it to be processed in different ways, leading to multiple ways of displaying and analyzing the same anatomical imaging or plane. These are difficult to learn and time consuming in the absence of specific training. In this article, we describe the key steps for volume acquisition of a 3D US volume, manipulation, and processing with reference to images of the fetal CNS, using a newly developed context-preserving rendering technique.

Joint European Society of Paediatric Radiology (ESPR) and International Society for Forensic Radiology and Imaging (ISFRI) guidelines: paediatric postmortem computed tomography imaging protocol.

Postmortem CT for investigating childhood deaths is increasingly utilised as a noninvasive adjunct or alternative to standard autopsy; however there are no standardised published imaging protocols. This article describes a standardised imaging protocol that has been developed based on current practices of international postmortem imaging practitioners and experts. This recommendation is expected to be useful for postmortem imaging centres wishing to update their existing practices and for those starting paediatric postmortem CT as a new service.

ESPR postmortem imaging task force: where we begin.

A new task force on postmortem imaging was established at the annual meeting of the European Society of Paediatric Radiology (ESPR) in Graz, Austria, in 2015. The postmortem task force is separate from the child abuse task force as it covers all aspects of fetal, neonatal and non-forensic postmortem imaging. The main focus of the task force is the guidance and standardization of non-radiographic postmortem imaging, particularly postmortem CT and postmortem MRI. This manuscript outlines the starting point of the task force, with a mission statement, outline of current experience, and short- and long-term goals.

Running a postmortem service--a business case and clinical experience.

The purpose of the postmortem examination is to offer answers to explain the cause and manner of death. In the case of perinatal, infant and paediatric postmortem examinations, the goal is to identify unsuspected associated features, to describe pathogenic mechanisms and new conditions, and to evaluate the clinical management and diagnosis. Additionally, the postmortem examination is useful to counsel families regarding the probability of recurrence in future pregnancies and to inform family planning. Worldwide the rate of paediatric autopsy examinations has significantly declined during the last few decades. Religious objections to postmortem dissection and organ retention scandals in the United Kingdom provided some of the impetus for a search for non-invasive alternatives to the traditional autopsy; however, until recently, imaging studies remained an adjunct to, rather than a replacement for, the traditional autopsy. In 2012, Sheffield Children's Hospital National Health Service Foundation Trust set up the service provision of minimally invasive fetal, perinatal and neonatal autopsy, while a postmortem imaging service has been running in Melbourne, Australia, since 2008. Here we summarise the essentials of a business case and practical British and Australian experiences in terms of the pathological and radiologic aspects of setting up a minimally invasive clinical service in the United Kingdom and of developing a clinical postmortem imaging service as a complementary tool to the traditional autopsy in Australia.

Fetal lung MRI and features predicting post-natal outcome: a scoping review of the current literature.

The outcome for infants with fetal lung pathologies not only depends on the nature of the pathology, but the impact it has on the developing lungs. The main prognostic factor is the degree of pulmonary hypoplasia, but this is not detectable pre-natally. Imaging techniques aim to simulate these features with a variety of surrogate measurements, including lung volume and MRI signal intensity. Despite the complexity of the various research studies and lack of consistent methodology, this scoping review aims to summarise current applications, and promising techniques requiring further investigation.

MRI features of perifibrinous deposits in the placenta due to COVID-19.

COVID-19 has been linked to pregnancy complications and loss (1). Infection during pregnancy is usually mild (2). The risk is highest in the third trimester with increased hospital admission rates and maternal and fetal compromise (3). Post-COVID placentitis is uncommon but the effect on the placenta and the fetus is extensive (4). We present a case correlating clinical, imaging, and pathological findings. Case Report: A 29-year-old para 2 gravida 1, with a normal fetal anomaly scan at 22 weeks gestational age (GA) contracted COVID at 24 weeks gestation. Fully recovered but reported reduced fetal movements at 27 weeks and 1 day. Imaging: US scan showed bright echoes within the brain, small lungs, and oligohydramnios. MRI showed abnormal brain signals, small lungs, and oligohydramnios but also a very abnormal placenta. Reduced and heterogeneous T2 signal and a marked reduction in the DWI signal intensity. The placental size was markedly reduced (volume 785.6 cm3 expected for GA is 5604.8-5952.4 cm3. The surface area of attachment was 3220 mm2, expected 22180.4-29293.2 mm2). Pathology: The placenta was small (fifth centile) with massive perivillous fibrin deposition and multifocal chronic deciduitis. Histology revealed placental chorionic villi showing diffuse sclerotic changes surrounded by perivillous fibrin deposition in the intervillous space. The basal plate revealed multifocal chronic deciduitis. When imaging the fetus, it is important to examine the placenta and correlate any abnormalities. The placenta is a forgotten organ and should be routinely included and assessed to allow the detection of important abnormalities.

Use of super resolution reconstruction MRI for surgical planning in Placenta accreta spectrum disorder: Case series.

INTRODUCTION: Comprehensive imaging using ultrasound and MRI of placenta accreta spectrum (PAS) aims to prevent catastrophic haemorrhage and maternal death. Standard MRI of the placenta is limited by between-slice motion which can be mitigated by super-resolution reconstruction (SRR) MRI. We applied SRR in suspected PAS cases to determine its ability to enhance anatomical placental assessment and predict adverse maternal outcome. METHODS: Suspected PAS patients (n = 22) underwent MRI at a gestational age (weeks + days) of (32+3±3+2, range (27+1-38+6)). SRR of the placental-myometrial-bladder interface involving rigid motion correction of acquired MRI slices combined with robust outlier detection to reconstruct an isotropic high-resolution volume, was achieved in twelve. 2D MRI or SRR images alone, and paired data were assessed by four radiologists in three review rounds. All radiologists were blinded to results of the ultrasound, original MR image reports, case outcomes, and PAS diagnosis. A Random Forest Classification model was used to highlight the most predictive pathological MRI markers for major obstetric haemorrhage (MOH), bladder adherence (BA), and placental attachment depth (PAD). RESULTS: At delivery, four patients had placenta praevia with no abnormal attachment, two were clinically diagnosed with PAS, and six had histopathological PAS confirmation. Pathological MRI markers (T2-dark intraplacental bands, and loss of retroplacental T2-hypointense line) predicting MOH were more visible using SRR imaging (accuracy 0.73), in comparison to 2D MRI or paired imaging. Bladder wall interruption, predicting BA, was only easily detected by paired imaging (accuracy 0.72). Better detection of certain pathological markers predicting PAD was found using 2D MRI (placental bulge and myometrial thinning (accuracy 0.81)), and SRR (loss of retroplacental T2-hypointense line (accuracy 0.82)). DISCUSSION: The addition of SRR to 2D MRI potentially improved anatomical assessment of certain pathological MRI markers of abnormal placentation that predict maternal morbidity which may benefit surgical planning.

Robert's uterus (asymmetric septate uterus): a rare congenital Müllerian duct anomaly.

Müllerian anomalies such as Robert's uterus, which was first described by the French gynaecologist Dr Helene Robert in 1969, are rare clinical entities and have been reported in <3% of the female population. Robert's uterus is a rare phenomenon with a relative dearth of reported cases. Affected individuals may present with pelvic pain and dysmenorrhoea that intensifies near menses or acutely, with severe abdominal pain to the emergency department. They are also associated with adverse pregnancy outcomes, abnormal fetal presentation, preterm labour, recurrent pregnancy loss and infertility. Although ultrasound has a role in its initial assessment, MRI is the best modality to further delineate its anatomy. It is typically managed via laparotomy and total horn resection, endometrectomy of the blind cavity or abdominal metroplasty. The authors present the case of a 40-year-old woman at 19+3 weeks gestation with acute onset of left-sided abdominal pain. A transvaginal ultrasound and MRI of the pelvis confirmed a Robert's uterus with a viable pregnancy in the upper left horn. She developed a ruptured horn with significant haemoperitoneum. An emergency laparotomy was performed and a non-viable fetus was evident. Only a few cases of pregnancy in the blind hemicavity have been reported so far. This case also highlights the importance of considering this diagnosis in young females presenting with dysmenorrhoea and normal menstrual flow. It is imperative to render a prompt diagnosis, as minimally invasive procedures may be more effective if detected before the formation of adnexal endometriomas.

Magnetic resonance imaging of the fetus.

Fetal magnetic resonance imaging (MRI) has become established as part of clinical practice in many centres worldwide especially when visualization of the central nervous system pathology is required. In this review we summarize the recent literature and provide an overview of fetal development and the commonly encountered fetal pathologies visualized with MRI and illustrated with numerous MR images. We aim to convey the role of fetal MRI in clinical practice and its value as an additional investigation alongside ultrasound yet emphasize the need for caution when interpreting fetal MR images especially where experience is limited.

Neuro-developmental outcome at 18 months in premature infants with diffuse excessive high signal intensity on MR imaging of the brain.

BACKGROUND: Diffuse excessive high signal intensity (DEHSI) may represent damage to the white matter in preterm infants, but may be best studied alongside quantitative markers. Limited published data exists on its neuro-developmental implications. OBJECTIVE: The purpose of this study was to assess whether preterm children with DEHSI at term-corrected age have abnormal neuro-developmental outcome. MATERIALS AND METHODS: This was a prospective observational study of 67 preterm infants with MRI of the brain around term-equivalent age, including diffusion-weighted imaging (DWI). Images were reported as being normal, overtly abnormal or to show DEHSI. A single observer placed six regions of interest in the periventricular white matter and calculated the apparent diffusion coefficients (ADC). DEHSI was defined as (1) high signal on T2-weighted images alone, (2) high signal with raised ADC values or (3) raised ADC values independent of visual appearances. The neuro-development was assessed around 18 months' corrected age using the Bayley Scales of Infant and Toddler Development (3rd Edition). Standard t tests compared outcome scores between imaging groups. RESULTS: No statistically significant difference in neuro-developmental outcome scores was seen between participants with normal MRI and DEHSI, regardless of which definition was used. CONCLUSION: Preterm children with DEHSI have similar neuro-developmental outcome to those with normal brain MRI, even if the definition includes objective markers alongside visual appearances.

"Why didn't we do it"? Reproductive loss and the problem of post-mortem consent.

Informed consent has been a much debated topic within the social sciences. It often forms a central feature of discussions on research in medical settings and in social research methods more broadly. While sympathetic to its' underlying principles of autonomy and choice, social scientists have tended to argue that these are seldom enacted in research or clinical practice. Rather, such principles are often circumscribed by wider social structures and by a culture of medical dominance. Drawing on data from a qualitative study on perinatal post-mortem, this paper explores informed consent in the emotionally charged clinical arena of perinatal pathology. Our in-depth analysis will provide fresh insight into post-mortem decision-making in the sensitive arena of baby loss. Our findings show how parents often found it difficult to give consent for post-mortem, and also for professionals to take consent from parents. It was also not uncommon for parents to experience regret over non-consent later on. One of our key findings, however, related to the sense of emotional and diagnostic closure often afforded by post-mortem when consent had been given. We conclude by arguing that, although we cannot resolve the tension between the principles of consent and their enactment in practice, we can develop a reflexive approach with which to navigate the process. In doing so, the paper contributes to wider sociological discussions on the meaning and use of informed consent in various settings beyond medical contexts.

T2*-weighted MRI produces viable fetal "Black-Bone" contrast with significant benefits when compared to current sequences.

OBJECTIVES: Fetal "black bone" MRI could be useful in the diagnosis of various skeletal conditions during pregnancy without exposure to ionizing radiation. Previously suggested susceptibility-weighted imaging (SWI) is not available in the suggested form on all scanners leading to long imaging times that are susceptible to motion artefacts. We aimed to assess if an optimized T2*-weighted GRE sequence can provide viable "black bone" contrast and compared it to other sequences in the literature. METHODS: A retrospective study was conducted on 17 patients who underwent fetal MRI. Patients were imaged with an optimized T2*-weighted GRE sequence, as well as at least one other "black-bone" sequence. Image quality was scored by four blinded observers on a five-point scale. RESULTS: The T2*-weighted GRE sequence offered adequate to excellent image quality in 63% of cases and scored consistently higher than the three other comparison sequences when comparing images from the same patient. Image quality was found to be dependent on gestational age with good image quality achieved on almost all patients after 26 weeks. CONCLUSIONS: T2*-weighted GRE imaging can provide adequate fetal "black bone" contrast and performs at least as well as other sequences in the literature due to good bone to soft tissue contrast and minimal motion artefacts. ADVANCES IN KNOWLEDGE: T2*-weighted fetal "black-bone" imaging can provide excellent bone to soft tissue contrast without using ionizing radiation. It is as good as other "black bone" sequences and may be simpler and more widely implemented, with less motion artefacts.

Neonatal cochlear function: measurement after exposure to acoustic noise during in utero MR imaging.

PURPOSE: To establish whether fetal exposure to the operating noise of 1.5-T magnetic resonance (MR) imaging is associated with cochlear injury and subsequent hearing loss in neonates. MATERIALS AND METHODS: The study was performed with local research ethics committee approval and written informed parental consent. Neonatal hearing test results, including otoacoustic emission (OAE) data, were sought for all neonates delivered in Sheffield who had previously undergone in utero MR imaging between August 1999 and September 2007. The prevalence of hearing impairment in these neonates was determined, with corresponding 95% confidence intervals calculated by using the binomial exact method, and mean OAE measurements were compared with anonymized local audiometric reference data by using the t test. RESULTS: One hundred three neonates who had undergone in utero MR imaging were identified; 96 of them had completed hearing screening assessment. Thirty-four of these babies were admitted to the neonatal intensive care unit (NICU), and one of them had bilateral hearing impairment. The prevalence of hearing impairment was 1% (one of 96; 95% confidence interval: 0.03%, 5.67%), which is in accordance with the prevalence expected, given the high proportion of babies in this study who had been in the NICU (ie, NICU graduates). In addition, for the well babies, there was no significant difference in mean OAE cochlear response compared with that for a reference data set of more than 16,000 OAE results. When NICU graduates were included in the comparison, a significant difference (P = .002) was found in one of four frequency bands used to analyze the cochlear response; however, this difference was small compared with the normal variation in OAE measurements. CONCLUSION: The findings in this study provide some evidence that exposure of the fetus to 1.5-T MR imaging during the second and third trimesters of pregnancy is not associated with an increased risk of substantial neonatal hearing impairment.

Diffusion-weighted imaging of cerebral white matter and the cerebellum following preterm birth.

AIM: The aim of this study was to determine if apparent diffusion coefficients (ADCs) generated with diffusion-weighted imaging of cerebral white matter and the cerebellum are affected by white matter damage. METHOD: Seventy-two preterm infants (32 males, 40 females; mean gestational age at birth 30.3 wks, SD 3.0 wks; mean birthweight 1458g, SD 534g) underwent magnetic resonance imaging of the brain around term-equivalent age and were categorized into three groups: normal, overt abnormality, and diffuse excessive high signal intensity (DEHSI). ADC values were calculated from cerebral white matter, cerebellar hemispheres, and cerebellar midline, and were compared between groups. Regression analysis identified clinical parameters correlated with ADC values. RESULTS: Imaging was normal in 27 infants, and revealed overt abnormalities in 14 and DEHSI in 31. ADC values did not differ between groups. ADC values from cerebral white matter were negatively correlated with the number of episodes of postnatal sepsis (p=0.002). ADC values from cerebellar hemispheres (p=0.007) and cerebellar midline (p=0.036) correlated with gestational age at birth. INTERPRETATION: ADC values from white matter are not altered in preterm infants with DEHSI but are negatively correlated with the number of episodes of postnatal sepsis. ADC values in the cerebellum are not altered by white matter damage, but are affected by preterm birth itself.

Appearances of diffuse excessive high signal intensity (DEHSI) on MR imaging following preterm birth.

BACKGROUND: Diffuse damage to the periventricular white matter has recently been suggested to be a cause of the cognitive deficits seen following preterm birth. It is unclear whether this form of injury can be visualised on MR imaging, but one group has described diffuse excessive high signal intensity (DEHSI) as a possible form of diffuse white matter injury. This finding is dependent on window imaging and the subjective assessment of the reviewer, but little data have been published on the degree of subjectivity on its appearance among raters. OBJECTIVE: To assess the subjectivity of DEHSI on conventional and ultrafast T2-weighted MR imaging following preterm birth. MATERIALS AND METHODS: An observational study of 40 preterm infants who had MR imaging of the brain around term-equivalent age, including conventional fast spin-echo (FSE) and ultrafast single-shot fast spin-echo (SSFSE) T2-weighted sequences in the axial plane. Images were anonymised and scored twice by four observers for the presence of DEHSI. Inter- and intra-observer agreement were calculated. RESULTS: Sixty-five percent of conventional and 100% of the ultrafast images were of diagnostic quality. DEHSI was noted in between 0% and 69.2% of conventional images and 27.5-90% of the ultrafast images. Inter- and intra-observer agreement ranged from none to moderate. CONCLUSION: The visual appearances of DEHSI on conventional FSE and ultrafast SSFSE T2-W images are highly subjective, limiting its clinical application.