Spontaneous Regression of Fetal Dural Sinus Malformation

Dural sinus malformations are rare congenital forms of dural arteriovenous shunt. Our goal is to describe prenatal ultrasonography and magnetic resonance imaging (MRI) findings of a thrombosed midline dural venous malformation. Second-trimester fetal ultrasonography and MRI demonstrated a large T2-hypointense mass centered at the level of the torcular Herophili consistent with complete thrombosis of a dural sinus malformation. A follow-up third-trimester MRI showed decreased thrombus size and no parenchymal injury. A neurologically intact newborn was delivered. Dural sinus malformations can lead to fetal intracranial thrombosis. Prenatal imaging is useful to establish the diagnosis of dural sinus malformations and to plan perinatal management and treatment options.

To investigate the diagnostic performance of fetal cardiovascular magnetic resonance imaging (MRI) using Doppler ultrasound (DUS) gating for the evaluation of the standardized five axial views in comparison with fetal echocardiography. In this prospective study 29 pregnant women (median: 34.4 weeks of gestation) underwent fetal cardiovascular MRI using DUS gating at 3 Tesla. The standardized five axial views in prenatal screening (fetal abdomen, four-chamber view, left ventricular outflow tract, right ventricular outflow tract, and three-vessel view) were independently assessed and analysed by both fetal MRI and fetal echocardiography on the same day. Image analysis included qualitative assessment and quantitative measurements of cardiovascular structures. MR image quality was assessed using a 4-point scale (from 1 = low to 4 = excellent). Postnatal echocardiography was performed for validation. 17/28 fetuses (60.7%) had pathological findings [16 congenital heart defect (CHD), one diaphragmatic hernia] in prenatal echocardiography. One fetus was excluded due to severe motion. Overall sensitivity and specificity in detecting fetal cardiac abnormalities was 88% and 100%, respectively, for fetal MRI and 100% and 100% for fetal echocardiography. MR image quality for evaluation of cardiac structures was high with a mean score of 2.8 (±0.8) (score 4: 15.9%, score 3: 53.8%, score 2: 19.3%, score 1: 11%). Quantitative measurements did not differ between fetal cardiovascular MRI and fetal echocardiography (all p > 0.05). Diagnostic performance of fetal cardiovascular MRI using DUS gating was comparable to fetal echocardiography. Fetal cardiovascular MRI using DUS gating might be a valuable diagnostic adjunct for the prenatal evaluation of CHD.

Joubert syndrome is a rare autosomal recessive disorder characterized by ataxia, developmental delay, and oculomotor and respiratory abnormalities in relation to cerebellar vermian and midbrain dysgenesis. The midbrain dysgenesis is responsible for the molar tooth sign on axial magnetic resonance imaging (MRI). This classic hallmark of Joubert syndrome has been identified in other disorders sharing overlapping clinical and radiologic features with Joubert syndrome. Recent identification of two different genes points to genetic heterogeneity in this group of disorders, now entitled Joubert syndrome and related disorders, making a genetic prenatal diagnosis not readily available. In addition, fetal ultrasonography lacks sensitivity in regard to posterior fossa malformation. Fetal MRI is now acknowledged as the method of choice to delineate posterior fossa malformation in a fetus. The identification of a molar tooth sign has, however, rarely been documented by a fetal brain MRI. We report a case of Joubert syndrome diagnosed prenatally using fetal MRI. We also discuss the etiology of Joubert syndrome in view of the recent genetic advances and murine models of cerebellar dysgenesis.

Background:Foetal thoracic lesions are uncommon, with the incidence of 1 in 15,000 live births. Antenatal monitoring of these lesions is required to prognosticate the parents about the postnatal outcome of the lesions and about the well-being of the baby. Foetal ultrasound and magnetic resonance imaging (MRI) are the modalities to detect these lesions and follow-up during pregnancy and postnatally. Congenital pulmonary adenomatoid malformations (CPAM), congenital diaphragmatic hernia (CDH) and bronchopulmonary sequestrations (BPS) are the commonly detected foetal thoracic lesions. Parameters such as congenital cystic adenomatoid malformation (CCAM) volume ratio (CVR) and lung-to-head ratio (LHR) determine the prognosis of these lesions. With this background, we planned to study the prognosis and outcome of antenatally detected thoracic lesions.Materials and Methods:This was a prospective study carried out for 2 years (January 2017 to December 2018). Pregnant females with foetuses diagnosed to have thoracic lesions on the second- and third-trimester ultrasound and foetal MRI were enrolled for the study. CVR and LHR were noted. Outcomes were analysed in terms of the need of termination of pregnancy, foetal or neonatal demise and need of surgery or conservative management.Results:Of a total of 521 pregnancies, thoracic lesions were detected in 22 (4.22%) cases. Individually, the incidence of each lesion was: CPAM-10 (45.45%), BPS-5 (22.73%), CDH-5 (22.73%) and congenital higher airway obstruction-2 (9.1%). Chromosomal screening was normal in 100% of cases. Follow-up was done for 2 years. Termination of pregnancy was required in 3 (13.64%) cases, postnatal death occurred in 4 (18.2%) cases, surgery was required in three cases of CDH soon after birth and two cases of extralobar BPS at 2 years of age. 10 (45.45%) cases were managed conservatively, who are doing well at 2-year follow-up.Conclusion:CPAMs, BPSs and CDH are the commonly detected antenatal thoracic lesions. Ultrasonography and MRI help detect and prognosticate the parents about the outcomes of these lesions. CVR and LHR with associated congenital malformations are important prognostic markers for these lesions. There is a need of long-term prospective studies to delineate the natural history of these lesions.

ObjectivesFetal cardiovascular magnetic resonance imaging (MRI) offers a potential alternative to echocardiography, although in practice, its use has been limited. We sought to explore the need for additional imaging in a tertiary fetal cardiology unit and the usefulness of standard MRI sequences.MethodsCases where the diagnosis was not fully resolved using echocardiography were referred for MRI. Following a three‐plane localiser, fetal movement was assessed with a balanced steady‐state free precession (bSSFP) cine. Single‐shot fast spin echo and bSSFP sequences were used for diagnostic imaging.ResultsTwenty‐two fetal cardiac MRIs were performed over 12 months, at mean gestation of 32 weeks (26–38 weeks). The majority of referrals were for suspected vascular abnormalities (17/22), particularly involving the aortic arch (n = 10) and pulmonary vessels (n = 4). Single‐shot fast spin echo sequences produced ‘black‐blood’ images, useful for examining the extracardiac vasculature in these cases. BSSFP sequences were more useful for intracardiac structures. Real‐time SSFP allowed for dynamic assessment of structures such as cardiac masses, with enhancement patterns also allowing for tissue characterisation in these cases.ConclusionsFetal vascular abnormalities such as coarctation can be difficult to diagnose by using ultrasound. Fetal MRI may have an adjunctive role in the evaluation of the extracardiac vascular anatomy and tissue characterisation. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd.

Toxoplasmosis (TOXO), cytomegalovirus (CMV), and Zika vírus (ZIKV) are among the common infectious agents that may infect the fetuses vertically. Clinical presentations of these congenital infections overlap significantly, and it is usually impossible to determine the causative agent clinically. The objective was the comparison of imaging findings in fetuses who underwent intrauterine infection by toxoplasmosis, CMV, and ZIKV. Confirmed cases of TOXO (2), CMV (3), and ZIKV (7) infections were included in the study over 10 months prospectively. Prenatal ultrasound (US), fetal magnetic resonance imaging (MRI), and postnatal neuroimaging (CT or MRI) were performed on all of the included cases and interpreted by an expert radiologist. The main neuroimaging findings in congenital toxoplasmosis were randomly distributed brain calcifications and ventricular dilatation on US, as well as white matter signal change on fetal brain MRI. The main neuroimaging findings of congenital CMV infection included microcephaly, ventriculomegaly and periventricular calcifications on US, as well as pachygyria revealed by fetal MRI. The case of congenital ZIKV infection showed microcephaly, ventriculomegaly, and periventricular calcifications on US, as well as brain atrophy and brain surface smoothness on fetal MRI. Increased placental thickness, hyperechogenic bowel, ascites and oligohydramnios were found CMV (1) and toxoplasmosis (1). IUGR was found in a CMV (2) and toxoplasmosis (1). Arthrogryposis was found in one case of ZIKV. Supporting information can be found in the online version of this abstract Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Fetal MRI of the central nervous system: State-of-the-art

Introduction: Dural sinus malformations, which are characterized by massively dilated dural sinuses, are one of the etiologies of an intracranial fetal cystic mass. Thrombi within these dural sinus malformations can develop while in-utero, and can be visualized by ultrasound in fetal life. Definitive postnatal diagnosis requires an autopsy. Case Report: We report two thrombosed fetal dural sinus malformations which are prenatally suspected during the second trimester with ultrasonography and postnatally confirmed with autopsy. Conclusion: Prenatal ultrasound images and fetal autopsy findings can be useful to establish the prenatal diagnosis of thrombosed dural sinus malformation.

Potential of magnetic resonance for imaging the fetal heart

As the safety and efficacy of fetal magnetic resonance imaging (MRI) at 3 tesla (T) continues to evolve, understanding its potential benefits and limitations is becoming increasingly important. We aim to compare the image quality of fetal MRI between 1.5T and 3T in routine clinical practice. Fetal MRIs performed at 3T between Jan. 1, 2019, and Dec. 31, 2019, at our institution were retrospectively reviewed by four fellowship-trained subspecialty radiologists. Imaging quality by system, sequence and artifacts were compared with matched controls at 1.5T and rated using a modified Likert scale. Thirty-three fetal MRIs at 3T were reviewed, and a control group of studies for the same clinical indication and equivalent gestational age were selected for comparison. Two of the four radiologists preferred 3-T image quality of the brain with slight agreement among the four reviewers (k=0.19, P=0.01). Three of the four radiologists had no preference for 1.5T vs. 3T in the majority of cases in evaluating the chest and abdomen. In the overall assessment, 3T was preferred in less than half of cases by all four radiologists (k=0.07, P=0.26). In the evaluation of standing wave, moire fringe and magnetic susceptibility artifacts, 3T was not preferred in the majority of studies by all four radiologists. Total exam time was significantly longer in the 3-T fetal MRIs (75.0±15.1min) compared to the 1.5-T fetal MRIs (55.5±13.3min, P<0.001). While 3T is a feasible alternative to 1.5T for fetal MRI, the increased artifacts and longer exam times observed at 3T without clear improvement in overall image quality make 1.5T preferable for fetal MRI in routine clinical practice.

Background: Fetal ventriculomegaly (VM) is defined as lateral ventricles measured above 10 mm. Some authors believe VM <12 mm are variants of the norm and need not be addressed for referral ultrasound.Methods: A retrospective continuous cohort study of 127 confirmed fetal VM was divided into three groups after initial referral sonographic assessment: isolated VM <12 mm (group A), isolated VM ≥12 mm (group B), and VM associated with other malformations (group C). We reviewed obstetric outcome and neonate evolution after 1 month with the aim of defining a pertinent prenatal workup.Results: We reported fetal infections in all groups (p = .24) and chromosomal abnormalities only in group C (p = .41). Fetal magnetic resonance imaging (MRI) found initially undiagnosed brain abnormalities in groups B and C (12.5 and 14.1%, p < .05). Ratios of healthy children after 1 month stemming, respectively, from groups A, B, and C were 66.7, 62.5, and 20.2% (p < .05).Conclusions: Our results are in favor of a systematic referral ultrasound for every fetal VM, regardless of size, as soon as definition criterion is met. Additional paraclinical assessment (maternal serologic status for toxoplasmosis and cytomegalovirus, amniocentesis, fetal cerebral MRI) should be discussed depending on the situation.

To investigate women's psychological reactions when undergoing fetal magnetic resonance imaging (MRI), and to estimate whether certain groups, based on clinical and sociodemographic variables, differ in their subjective experiences with fetal MRI and in their anxiety levels related to the scanning procedure. This study is a prospective cohort investigation of 62 women before and immediately after fetal MRI. Anxiety levels and subjective experiences were measured by questionnaires. Groups based on clinical and sociodemographic variables were compared with regard to anxiety levels and to the scores on the Prescan and Postscan Imaging Distress Questionnaire. Anxiety scores before fetal MRI were 8.8 points higher than those of the female, nonclinical, norm population (P<.001). The severity of the referral diagnosis showed a linearly increasing effect on anxiety level before MRI (weighted linear term: F1,59=5.325, P=.025). Magnetic resonance imaging was experienced as unpleasant by 33.9% (95% confidence interval [CI] 21.2-46.6%) and as hardly bearable by 4.8% (95% CI 0-17.5%) of the women. Physical restraint (49.9%, 95% CI 37.4-62.4%), noise level (53.2%, 95% CI 40.7-65.7%), anxiety for the infant (53.2%, 95% CI 40.7-65.7%), and the duration of the examination (51.6%, 95% CI 39.1-64.1%) were major distressing factors. Women who undergo fetal magnetic resonance imaging experience considerable distress, especially those with poor fetal prognoses. Ongoing technical developments, such as a reduction of noise, shortening the duration of the MRI, and a more comfortable position in open MRI machines, may have the potential to improve the subjective experiences of women during fetal MRI. III.

PurposeSacrococcygeal teratomas (SCT) can be detected in ultrasonography as early as in the first trimester. Currently, prenatal ultrasonography enables a thorough examination of tumors, but it is not always sufficient. The purpose of this study was to determine the most important features of SCTs in fetal magnetic resonance imaging and to confront them with postnatal computed tomography (CT).Case reportBetween 2009 and 2013, 5 cases of sacrococcygeal teratomas were diagnosed in our hospital using fetal magnetic resonance imaging (3 female and 2 male infants). Three of the affected newborns underwent postnatal CT before surgery. In each case, tumor size, its content, mass effect, and classification according to the Altman’s criteria were determined and compared with other features. Fetal magnetic resonance imaging (MRI) and postnatal CT were in excellent agreement with respect to tumor classification using the aformentioned criteria. MRI better characterizes tumor content and its extent compared to ultrasound, and enables a precise structural assessment of the central nervous system. Postnatal CT is complementary to fetal MRI and optional.ConclusionsFetal MRI may help in the prenatal diagnosis of SCTs as it overcomes the limitations of obstetric ultrasound. Postnatal computed tomography is useful in determining tumor vascularity or calcifications, and it can depict the surrounding bone structures.

Fetal magnetic resonance imaging (MRI) is nowadays an established second-line imaging modality next to prenatal ultrasound (US). Ultrafast fetal MR sequences allow to “picture freeze” the fetus in utero without the need for sedation. The goal of fetal MRI is to offer an enhanced visualization and characterization of the pathologies detected by routine prenatal sonography, and it is therefore used as a problem-solving technique in a selected patient population. Prenatal sonography remains the imaging modality of choice for evaluating disorders related to the fetus and pregnancy; however, occasionally fetal MRI can identify subtle lesions that remained uncovered by US but may be essential for accurate diagnosis. Furthermore, fetal MRI contributes to selection of intrauterine treatment options and obstetric management, determines immediate postnatal care, and enhances parental counseling. MRI of the fetal brain and spine provides a higher sensitivity and specificity compared to prenatal US, because of several inherent US limitations. Depending on the maternal habitus, maternal bowel gasses, amount of amniotic fluid, and positioning of the child in utero, visualization of the fetal central nervous system (CNS) may be limited by US. Furthermore, the progressing development of the fetal cartilaginous/osseous calvarium and spinal canal during pregnancy may obscure lesions close to the skull or vertebral bodies on US examination. The goal of the workshop is to become familiar with the imaging protocol and indications for fetal MRI of the CNS, enhance your expertise about interpreting fetal MRI of the brain and spine, and become familiar with developmental variants of the fetal brain and spine.

Fetal neuroimaging applications for diagnosis and counseling of brain anomalies: Current practice and future diagnostic strategies